Strange new 'species' of ultra-red galaxy discovered
This artist's conception portrays four extremely red galaxies that lie almost 13 billion light-years from Earth. Discovered using the Spitzer Space Telescope, these galaxies appear to be physically associated and may be interacting. One galaxy shows signs of an active galactic nucleus, shown here as twin jets streaming out from a central black hole. Credit: David A. Aguilar (CfA)
In the distant reaches of the universe, almost 13 billion light-years from Earth, a strange species of galaxy lay hidden. Cloaked in dust and dimmed by the intervening distance, even the Hubble Space Telescope couldn't spy it. It took the revealing power of NASA's Spitzer Space Telescope to uncover not one, but four remarkably red galaxies. And while astronomers can describe the members of this new "species," they can't explain what makes them so ruddy.
"We've had to go to extremes to get the models to match our observations," said Jiasheng Huang of the Harvard-Smithsonian Center for Astrophysics (CfA). Huang is lead author on the paper announcing the find, which was published online by the Astrophysical Journal.
Spitzer succeeded where Hubble failed because Spitzer is sensitive to infrared light - light so red that it lies beyond the visible part of the spectrum. The newfound galaxies are more than 60 times brighter in the infrared than they are at the reddest colors Hubble can detect.
Galaxies can be very red for several reasons. They might be very dusty. They might contain many old, red stars. Or they might be very distant, in which case the expansion of the universe stretches their light to longer wavelengths and hence redder colors (a process known as redshifting). All three reasons seem to apply to the newfound galaxies.
All four galaxies are grouped near each other and appear to be physically associated, rather than being a chance line-up. Due to their great distance, we see them as they were only a billion years after the Big Bang - an era when the first galaxies formed.
"Hubble has shown us some of the first protogalaxies that formed, but nothing that looks like this. In a sense, these galaxies might be a 'missing link' in galactic evolution" said co-author Giovanni Fazio of the CfA.
Next, researchers hope to measure an accurate redshift for the galaxies, which will require more powerful instruments like the Large Millimeter Telescope or Atacama Large Millimeter Array. They also plan to search for more examples of this new "species" of extremely red galaxies.
"There's evidence for others in other regions of the sky. We'll analyze more Spitzer and Hubble observations to track them down," said Fazio.
Provided by
Harvard-Smithsonian Center for Astrophysics
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Dec 01, 2011
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"...Thus (value of) alpha depends upon the energy at which it is measured, increasing with increasing energy, and is considered an effective or running coupling constant. Indeed, due to e e- and other vacuum polarization processes, at an energy corresponding to the mass of the W boson (approximately 81 GeV, equivalent to a distance of approximately 2 x 10-18 m), (mW) is approximately 1/128 compared with its zero-energy value of approximately 1/137. Thus the famous number 1/137 is not unique or especially fundamental... blah, blah..."
http://physics.ni...pha.html
So, if the universe was formed at the GUT energy, then the value of alpha should be zero, because all forces were equal that "time". We don't observe it, which introduces a problem for Big Bang theory.
Dec 01, 2011
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http://www.aether...rchy.gif
The standard Big Bang model predict instead, due the expansion of space-time the remote galaxies should appear smaller. This hasn't been confirmed with observations, which are supporting dense aether model instead.
http://arxiv.org/abs/1011.4956
Dec 01, 2011
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Aren't all constants derived from measurement just approximations with a shrinking degree of uncertainty in measurement ?
Dec 01, 2011
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This can be shown to be trivially false.
__________dimensions_____distance(Mly)
M 31......190'x60'........2.54
M 33......71'x42'.........2.7
M 81......27'x14'.........11.8
NGC 253...27.5'x7'........11.4
compared to ANY galaxy in the HUDF, HDF-N or HDF-S over a billion light years distant is well under 2 arcminutes in apparent diameter. Astronomers can see apparent size-distance differences *within* the galaxies sampled in the Hubble deepfields. More distant galaxies do appear smaller than nearby galaxies.
This most definitely has been confirmed with *many* observations(eg): http://arxiv.org/...33v1.pdf
Dec 01, 2011
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I've also found that ultra-violet is so violet that it lies beyond the visible part of the spectrum, and X-rays should be renamed ultra ultra violet, because they are so ultra violet that they lie beyond the ultra violet spectrum. and gamma rays should be called ultra ultra ultra violet.
If the article can't be comprehended by an elementary school student, they shouldn't bother using explanations you would tell an elementary student.
Look, we all understand that infrared light has a shorter wavelength than the visible spectrum and is just beyond our ability to see.
Dec 01, 2011
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Maybe not all of us. Infrared has a LONGER wavelength. :)
Dec 01, 2011
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lay a balloon out flat and draw a smiley face on it. Next, stretch it out to twice its original size, and move it twenty feet away. This accounts for the expansion of space since the light from these galaxies was emmitted.
For things we can see, this effect is relatively small. However, the point is that anything we see will look proportionally larger, due to the fact that space has not been geometrically static in the last 10 billion years.
Theoretically, if you had a clear line of sight on galaxies going all the way to the big bang, they would eventually stop becoming smaller, and start becoming bigger and much fainter
Finally as this effect becomes substantially more pronounced, you get to the CMB, which is the light from a single tiny point spread all across the sky.
Dec 01, 2011
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LMAO. I was so involved in making a parody of the shorter wavelengths that it came out wrong when i got back to infrared.
Dec 01, 2011
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Dec 01, 2011
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If the light from the galaxies is 13B ly, only 1B from the big bang, why do we not see light on the other side of the big bang? Theoretically, there should be another 13B ly of galaxies on the other side of the big bang. Either that or the big bang was only 7B ly away from us.
Dec 02, 2011
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Dec 02, 2011
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Dec 02, 2011
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right on, i cant either. Just think of the possibilities.....breathtaking really. sadly it doesnt look like it will be going up as soon as originally planned as last i heard they were aiming for something like 2018 for launch and with nasa the way they are we can probably expect more like 2020, if the project isnt somehow killed by the republicans before then.
Dec 02, 2011
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Dec 02, 2011
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"Finally as this effect becomes substantially more pronounced, you get to the CMB, which is the light from a single tiny point spread all across the sky." - That guy
The CBR comes from a time well beyond the singularity when the universe made a transition from a radio-opaque plasma to a radio-transparent diffuse neutral gas.
Plasma's eat EM Radiation.
Dec 02, 2011
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The BB theory does not require the universe to be any particular size and in fact it may be infinite in extent. However we can only observe out to 13 billion light years in any direction.
Rather than thinking of universe as a some kind of bag, consider that it is infinite in extent and that the ruler you are using to measure size is shrinking.
Because your ruler is shrinking you see distant objects as moving away from you.
Because your ruler is shrinking you see the light that they emitted apparently getting longer in wavelength and hence redder.
Because your ruler is shrinking in length you see that the farther an object is from you the faster it seems to move away.
Now consider the universe evolving backward in time. Your ruler gets longer and longer , things appear to get closer and closer until eventually things begin to overlap and merge, the entire universe will eventually overlap and every ruler cont
Dec 02, 2011
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That is the singularity from which the universe evolved from.
However there is a complication. Time slows down as the energy density of the space it is moving through increases. So the closer you get to the singularity the longer it takes to get there.
As a result, there is no beginning. Just an infinite trend to infinite energy density.
From this perspective, there is no other side.
Dec 02, 2011
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Dec 02, 2011
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http://www.americ...folktale
Dec 02, 2011
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Dec 02, 2011
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So really every position in space today IS the place where the big bang happened. This is why we see the remnant radiation from that event (cosmic microwave background) coming from all directions. If it had been an explosion INTO space we'd only see it come from one direction.
Also the event was the beginning of what we call spacetime. So you can't really look further back because there is no 'further back' in time.
Dec 02, 2011
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Fair enough. The CMB spans the entire sky even though it comes from a much smaller area than it now appears to occupy - still working as an example of my point above. But corrected now, as vendicar pointed out.
Dec 02, 2011
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So really every position in space today IS the place where the big bang happened. This is why we see the remnant radiation from that event (cosmic microwave background) coming from all directions. If it had been an explosion INTO space we'd only see it come from one direction.
Also the event was the beginning of what we call spacetime. So you can't really look further back because there is no 'further back' in time.
I faithfully watch the History & Science channels "Universe" presentations. Their animations always show a "bang" (the focal point) from a massive single object from which all else originated as that explosion expanded & pushed stellar matter into the vacuous space around it. I don't understand how your post comports with commonly held "big bang" animations?
Dec 02, 2011
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Dec 02, 2011
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Example: If two galaxies are x lightyears apart and the universe doubled in size, then they would be 2x lightyears apart. So what determines that otherwise stable speed of light, if the very space it is measuring is expanding? That is not expanding space, but an increasing amount of stable space. So either we are at the exact center of the universe, or redshift is an optical effect, proportional to distance.
And that is why we will keep finding the signatures of ever more distant galaxies hidden in that background radiation.
Dec 02, 2011
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Dec 03, 2011
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I'm really trying hard to follow you here. Your statement "everything in the observable universe would have been at the same point around 13.7 billion years ago". This sounds exactly like a massive concentration of mass just as BB hypotheses states, yet you say such is "conceptually inaccurate". What is it that is conceptually inaccurate? The BB or what? It is crystal clear what message the animations wish to convey. Something is missing here.
Dec 03, 2011
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Their animations are misrepresentations based on ignorance of what is thought to have happened.
The real theory is more esoteric and more difficult to depict and explain.
Dec 03, 2011
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Good question. To a great extent the "stable" speed of light is just assumed.
So far no one has found any reason to question that assumption. Until that is... Until the universe becomes very energy dense. And then c becomes smaller and in the limit zero.
Dec 03, 2011
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So far there are no significant anomalies seen in the most distant galaxies, although there is some surprise that they managed to organize so early, and that some stars in them appear to be older than easily accounted for.
But there isn't sufficient evidence to say that anything has upset the BB theory, and there is substantial confirming evidence. For example, the structure of early galaxies is what is expected of galaxies early in their formation. Most of the stars are young, which is expected. Three are lots of active galactic nuclei which is what we expect with a higher density of interacting galaxies, etc.
Dec 03, 2011
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The Light of other days?
Dec 03, 2011
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We could start with that its illogical, defies commonsense, creates paradoxes, is hardly any different to the Biblical 'Creation' and is mostly a matter of belief rather than science.
Dec 03, 2011
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What is inaccurate is your perception of how all matter is condensed to a very small volume. It is, but then so is all of space, and that is the part you aren't getting.
Space itself contracts to the same point. There is no looking from the outside at the exploding universe, as there is no outside, since there is no space there.
It's not a bag, or a balloon, and it isn't an explosion as you know it, since there is nothing for the matter to explode into. neither is it necessarily finite, a universe that is infinite in extent might exist at the original singularity.
The graphics that depict the BB as an explosion do so out of ignorance and laziness. There was no explosion per say.
I described earlier the correct view, where the universe - possibly one of infinite extent, starts Cont.
Dec 03, 2011
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Dec 03, 2011
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The same can be said for the invariability of c. But there it is... Staring you in the face... Reality has no reason to conform to your view of how things should be.
If you don't like this universe, find yourself another one in which to live.
Dec 03, 2011
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This title suggests that observer are looking at energy that is far away from its source.
Why? Energy is stored as rest mass and usually released in radiation of extremely short wave length, e.g., gamma rays.
The natural sequence of events is usually like this:
Rest mass => Gamma rays => X-rays =>
UV-radiation => Visible-light => IR
With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://myprofile....anuelo09
Dec 03, 2011
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Dec 03, 2011
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If one follows the conditions at any given point in the universe back in time it will eventually be very hot and very dense there. There is no outside of space from which one could watch the universe expand and cool as opposed to the case of an explosion.
Dec 03, 2011
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When all space was originally contained in a much smaller universe, were galaxy clusters still hundreds of millions of lightyears apart, but the light simply traveled slower, or is there a stable speed of light, so it took light less travel time?
Dec 03, 2011
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Dec 03, 2011
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Vendicar,
As I've understood it, those distant galaxies are considered young because the light only comes from the lightest elements(hydrogen, helium..) and therefore starts at the blue end of the spectrum. It occurs to me, that as the light is redshifted, the red end of the spectrum would be the first to fall off the visible scale and eventually we would only see what had started on the blue end, as the last visible light. So we would not be able to tell if these very distant galaxies had light from heavier elements, unless we fully examine the black body radiation around them. In that regard, it would be interesting to take the methods of observation mentioned in this article and apply them to what we consider those distant, young galaxies and see if there are not signatures of heavier elements hiding in them.
Dec 03, 2011
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The speed of light (in a vacuum) is a constant and equal to that measured near Earth over any region of space or time that is small compared to its curvature (which is produced by mechanical stress, mass, and energy). If something with non-zero rest mass follows a given path then it takes more time to do so than would a light beam following the same path in a vacuum.
General relativity is constructed so that the laws of physics are the same everywhere and at all times (over a small enough region for a given precision and amount of curvature). It follows that the speed of light (i.e., of an electromagnetic wave) is the same everywhere and at all times (over a small enough region in a vacuum)
Dec 04, 2011
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Why is that?
With the optical spectra now shifted into the Infared you look for the spectral lines of elements other than Hydrogen and Helium in the infared portion of th spectra.
It isn't rocket science.
Dec 04, 2011
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Dec 04, 2011
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Dec 04, 2011
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Dec 04, 2011
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So am I to assume the space between galaxy clusters, as measured by lightspeed, isn't expanding, but there would simply be an increased amount of the lightspeed units, thus taking longer for light to travel between them?
Do you understand that increasing distance is not the same as expanding space?
A train moving away from you is increasing distance, not expanding space. The problem for cosmology is that if it is only increasing distance in stable space, then we would appear to be at the center of the universe. For Big Bang theory to work, it has to be expanding space, yet this overlooks the fact that: "The speed of light (in a vacuum) is a constant and equal to that measured near Earth over any region of space or time that is small compared to its curvature"
How is it that the "vacuum" is stable, if space expands?
Dec 04, 2011
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Now we are looking in the infrared:
"Spitzer succeeded where Hubble failed because Spitzer is sensitive to infrared light - light so red that it lies beyond the visible part of the spectrum. The newfound galaxies are more than 60 times brighter in the infrared than they are at the reddest colors Hubble can detect."
So it will be interesting to see what comes of it.
Dec 04, 2011
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Part of my scientific training is astrophysics.. Yes.
" You're making it sound like a "creation" out of nothingness (God?)." - Benni
Creation requires a beginning and since there was none there is no creation.
"All the Astronomers on the Cience & History channels who are videoed outside the Griffith Observatory displaying all those marvelous "big bang animations" haven't a clue as to what they're talking about?" - Benni
They know. But they lack the ability to provide an animation that imparts the BB idea accurately.
I have provided you with a textual description that is precise in the way it captures the principle.
"And you're getting 5 star post ratings & I'm getting 1's?" - Benni
Because I have provided you with precise information, and you have not digested it.
Dec 04, 2011
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The vacuum isn't stable. That is why space is expanding.
As to c. It's velocity is measured locally. We do not have the means of measuring c billions of light years away.
We can do it on special occasions at distances that are hundreds of perhaps thousands of light years away.
Dec 05, 2011
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We have two yardsticks. With lightspeed, if those galaxies clusters are moving apart, we add more such units. That is increased distance. With the other yardstick, redshift, the same units just get stretched out to fill the extra distance. That's expanding space. This is not a problem?
Dec 05, 2011
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Then send us to your blogsite & share with us your expertise that is so far beyond our tiny little Astronomy club to "digest". Two members of our club are engineers, one a teacher, one a musician, one an auto mechanic, one an electronics technician. Our club knows about this site, now we would like to log on to yours.
Dec 05, 2011
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I would note that obviously we can only measure lightspeed locally, given the Voyager spacecraft have barely reached the heliopause, let alone traveled to other galaxies, but the issue the is theories tying such measurements together and how it can be argued that the very fabric of space expands, in order to explain the observation of redshift of distant galaxies and then turn around and say it will take light longer to bridge these distances and not have to explain what dimension of space it is that maintains this comparatively stable measure.
Dec 05, 2011
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"The problem for cosmology is that if it is only increasing distance in stable space, then we would appear to be at the center of the universe."
If the distribution is homogenous then there is no centre either way, the problem would be that if galaxies were moving through space and space were not expanding, they could not exceed the speed of light. In the big bang model, space is expanding as you say.
"The speed of light (in a vacuum) is a constant and equal to that measured near Earth over any region of space or time that is small compared to its curvature". How is it that the "vacuum" is stable, if space expands?
The speed of light is actually a geometric limit. If you think of the path of a distant galaxy which happens to be at rest in its local patch of space as a function of time, it appears to move away because the space between us and it is expanding. The speed of light is an angle of 45 degrees relative to the path of that galaxy.
Dec 05, 2011
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"As to c. It's velocity is measured locally. We do not have the means of measuring c billions of light years away. We can do it on special occasions at distances that are hundreds of perhaps thousands of light years away."
This paper is controversial as it claims a spatial gradient in the value of the fine structure constant which as you no doubt know is dependent on the speed of light. The claimed variation is about 10 ppm at a range of about 8 billion years lookback time:
http://arxiv.org/abs/1008.3907
It is notable that the gradient they claim is in the opposite sense from their previous paper.
Their value for the purely temporal change is 0.6 /- 1.6 ppm at 1 sigma out to z=1.8 which is entirely compatible with the null hypothesis, an unchanging speed of light.
You may have studied astrophysics but the views you are offering, while well disguised, are far from the conventional model.
Dec 05, 2011
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Fleetfoot,
If that galaxy cluster is 2 billion lightyears away, the light could have quite a few turns in its path over time and space to get to us. My point is about the theory. You say "the space between us and it is expanding." The theory assumes it will consequently take light longer, ie, more time, to cross this expanded space. This means that while there is more distance between us and that other galaxy, the speed of light is not relative to that expanding space, but to some other dimension/vacuum. What is this stable vacuum between galaxies which is the basis for lightspeed?
Dec 05, 2011
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Dec 06, 2011
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I understand the argument, but I'm still have trouble with the contradiction.
According to theory, the space is expanding, therefore it will take light longer to cross it. If these galaxies are moving away, such that the light takes longer to cross it, you are making a comparison between the space between the galaxies and the measure of space being crossed by light. A lightyear is about 10 trillion miles. So if it is taking more time for light to travel between to point, that means there are more miles between them. Obviously it wouldn't make sense if light did speed up as space increased, because we wouldn't be able to detect it.
Dec 06, 2011
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So since it only appears that gravity causes stars to move as their light passes through intermediate gravity fields, could it be that redshift is also a lensing effect? Such that while those other galaxies appear to be moving away from us, this is an optical effect and if we could observe the situation in a billion years, they would still be at the same general distances and still redshifted. That there is an outward curvature, similar to the inward curvature of gravity. This would explain a lot of things, such as why the rate of expansion is directly proportional to distance and resembles a cosmological constant, which was originially proposed to balance gravity.
Dec 06, 2011
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Dec 06, 2011
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Dec 06, 2011
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Because a stable speed of light would require a stable dimension of space. If there are simply more lightyears separating the two points, what is the frame on which this measure is based?
As with the doppler effect, the train is moving away in stable space, ie. it is putting space that was front of it, behind it, not that the space is being stretched. So if those galaxies are moving away and there are more lightyears between them, they are putting space, as measured in lightyears, that was outside the distance between them, in between them. This isn't stretching space, but increasing the amount of stable space.
Dec 06, 2011
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Just an idea, I'm a total outsider:
"Stable space is only relevant, where the light is now" Sorry. It's called Planck lenght.(?) Immagine light traveling Planck lenght by Planck lenght for 13 billion years. The distance of these redshifted galaxies was streched from about 3 billion lightyears to about 25-30 billion in this timeframe. All along the light traveled at the same speed, and covered 13 billion lightyears-worth of planck lenghts.
lomed, correct me please if i'm disastrously wrong here. I'm curious too.
Dec 06, 2011
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Whether your unit of distance is planck lengths, or lightyears, the same point holds. If the number of these lengths is increasing, that's an increased amount of stable space, as measured by that unit. If we use a stable unit to measure an expanding frame, what is the basis of that unit?
Dec 07, 2011
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Dec 07, 2011
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That shows up as gravitational lensing which is a small effect at best.
"You say 'the space between us and it is expanding.' The theory assumes it will consequently take light longer, ie, more time, to cross this expanded space. This means that while there is more distance between us and that other galaxy, the speed of light is not relative to that expanding space, but to some other dimension/vacuum."
Light travels at c relative to any free-floating matter in the region of space through which it is passing, that is the basic rule of relativity. The light crosses the first one 300,000km of distance to us in one second, i.e. at the usual speed. During that time the space ahead of it (and behind it) expands by some amount so the distance remaining reduces by less than one light-second. It covers the next lightsecond at the same speed etc..
Dec 07, 2011
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If I'm driving down a road at fifty mph and someone else passes me at ninety mph, the distance between us will increase, but that doesn't change the length of a mile.
So the space is expanding while the light is in transit. You are still using a stable unit to measure the distance. Even if the distance is increasing during this process, the size of the units are not affected by the change in distance, just more are required. If space is expanding, what determines the stability of this unit of measure?
Dec 07, 2011
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"If space is expanding, what determines the stability of this unit of measure?"
Physical constants.
"Whether your unit of distance is planck lengths, or lightyears, the same point holds."
i didn't suggested to change the unit of measure. I tried to point out, that space expands in a different way in large and in small scale. In large scale, it seems to strech. But at the very small scale the stucture of vacuum becomes "grainy". You reach a point, where it's made up by "units" that can not be streched or devided. To strech it at large scale, you have to add more and more of these units.
Dec 07, 2011
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Dec 07, 2011
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Without data we can't determine the correctness of your idea.
Dec 07, 2011
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In fact, gravitationally bound systems contract. Some so forcefully that light cannot escape and contracts as well. So it is only between these bound systems that space expands. According to measurements by COBE and WMAP, the expansion of space and its gravitational contraction are inversely proportional, resulting in flat space. So if space is falling into these bound systems at the same rate as it is expanding between them, where is the overall expansion coming from?
This might explain why the expansion resembles a cosmological constant, which was originally proposed to balance gravity.
Dec 08, 2011
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Dec 08, 2011
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Dec 08, 2011
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Yes, but you aren't there to experience the speed of separation.
Two objects can separate at speeds > c to a third observer. It is only motion relative to the observer that is constrained to be < c.
c is measured locally, and is a measured constant.
Dec 08, 2011
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Sorry Benni, I neither have a web site, or a blog. So feel free to cut and paste what has been said here.
Dec 08, 2011
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Sorry, I don't understand your complaint.
c is a local diffusion constant.
Electro-magnetism is such that the average rate of propagation - limited by the diffusion effect of the quantum vacuum - is c, and it is c everywhere since the diffusion constant is apparently c everywhere.
c, dl and dt are linked such that if c changes then we infer either a change in the local dl or dt.
On large scales we observe that the universe appears to be expanding. Yet in the limit as dt goes to zero, dl/dt goes to c.
As a practical matter we don't have an accurate enough standard for length to detect the expansion of the universe in the lab by measuring dl and dt.
Dec 08, 2011
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Well, certainly they differ in terms of the animations provided to students, but the results are the same.
Dec 08, 2011
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Time is a pretty tricky thing as it means different things to different people.
For example, to the photon the time needed to travel from the big bang to your eye is Zero seconds.
What we do when we look at distant galaxies, is impose a linear relationship and assume that dt and dl for us is the same dt and dl for distant galaxies. For low recessional velocities, this practical assumption is a good one, but as apparent recessional velocities approach c, then that linear assumption begins to produce confusing results.
One such result is that the universe had an origin. But again to a photon that origin was 0 seconds ago.
In reality as you get closer to the "origin" of the universe there are various competing factors that confuse what time is, one of which is the energy density which tends to infinity Cont.
Dec 08, 2011
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Higher spatial energy densities reduce the value of c. As energy density increases to infinity, c decreases to zero relative to a distant flat space coordinates that are projected toward the past. Yet locally it is thought that c remains constant so either local dl and local dt must decrease to produce the same value of c.
So we see lengths contracting and local time contracting as the universe approaches the singularity. The sum of the local time goes to infinity for the local observer, but since we project our time linearly into the past, we see an initial time.
So proper time since the origin is infinite, we see the time to the beginning as having a fixed origin and a photon sees the beginning as now.
It is all a matter of perspective.
Dec 08, 2011
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Again. c is a local diffusion constant.
We do not have instrumentation accurate enough to measure the expansion of the universe by detecting variance in c. If we did then we would conclude that the variance in c was a result of the expansion of the universe.
c is "constant" only in small regions.
As a practical matter, if a variance of c was observed it would be attributed to something other than a variance in c in order to keep c constant.
If such an observation were made, there would be considerable debate of the merits of how to proceed and keep science consistant. But because physicists love their constants undoubtedly they would keep c, and manufacture new physical laws to explain how c is really not changing.
Such re-definitions of physical laws show how science is mutable and ultimately about prediction rather than explanation.
Dec 08, 2011
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Every physicist I have ever known has written a paper on something, it's how they get name recognition within their profession, by their association in professional organizations. Send us to one of the organizations of which you are a member so we can evaluate abstracts & papers you have submitted.
Dec 08, 2011
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Dec 08, 2011
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So we have these enormous theoretical patches, from inflation to dark energy, to make this ad-hoc explanation work, while observations supporting redshift being evidence of a cosmological constant, as originally proposed, to balance gravity, is overlooked, since groupthink insists on the Big Bang. As the article states, "We've had to go to extremes to get the models to match our observations,"
Dec 08, 2011
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Dec 08, 2011
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http://www.fqxi.o...kets.pdf
Dec 08, 2011
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However, said mechanism would not be a good explanation for the cosmological redshift. Since it produces redshift via dispersion and attenuation it would change the shape of the spectra observed with respect to that emitted. For example, one would expect a hot gas to emit thermally like a blackbody, but with this sort of redshift one would not receive a blackbody spectrum. Rather, the observed spectrum would be broader and have the lower frequencies enchanced (in addition to having its peak shifted to a lower frequency). In particular, this would happen to the CMB contrary to observation. It would also lead to discrepancies between the observed absorption line of gases and the temperatures indicated by the overall shape of the (thermal) spectra.
Dec 09, 2011
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The point isn't that it's an answer to everything, but that there are far too many angles to this issue for Big Bang theory to be more than speculative, rather than taken for granted by anyone who wishes to taken seriously. Additions such as inflation and dark energy really are nothing more than enormous gaps between theory and observation.
With all the various advanced telescopes coming on line, I suspect the problems will become more obvious.
Dec 09, 2011
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Dec 10, 2011
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Dec 23, 2011
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What can we can not observe 13 billion light years away.
Could we see the Milky Way 13 billion light years away, would the majority of the light we can see from the stars in the Milky Way to be gone. Most of the stars will disappear at a distance of 13 billion light years and the stars who has the strongest evidence of metals will be gone.
The scientific term for things science can not observe is that it does not exist.
Perhaps the reason that the most distant galaxies do not have stars with high metal display, may be because astronomers can not observe them, because their light is too weak.
Dec 23, 2011
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Dec 25, 2011
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Really? You mean that the universe really does get 2.5 billion miles less wide as you accelerate in your car from 0 to 60 mph?
How does space know how to do this? And doesn't that rate of contraction exceed c?
How do you manage to send a message to the far side of the universe in the 6 seconds it takes you to accelerate to 60 Mph?
The contraction and expansion of space are real are they?
Dec 25, 2011
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The proposition is that two positrons are two electrons moving backward in time.
Place two positrons side by side and since both have positive charge they repel.
Reverse the arrow of time and you have two electrons sitting side by side and they attract.
Since that is not what is seen in the real world it follows that time reversal does not convert electrons into positrons or positrons into electrons.
Dec 25, 2011
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Claptrap.
The proportion of light from metal abundant and metal free stars would be the same.
All dim at the same rate.
Dec 25, 2011
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Dec 25, 2011
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Are you suggesting gravity has polarity?
Dec 25, 2011
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Dec 26, 2011
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Does AWT presume "radiation" (electro-magnetic waves), counter oppose gravity with exactly the same "force"?
Dec 26, 2011
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http://aetherwave...age1.gif
In massive stars and galaxies the pressure of EM radiation is really the main force, which defies their gravity. But this radiation is of long distance character and volatile and such stars evaporate in this way. When the density of star increases above certain limit, it crashes and the another, short dist. radiation must apply in form of radiation pressure of gluons and W/Z bosons. And the large galaxies are held apart with dark matter, which is the manifestation of graviton flux, i.e. the flux of gravitational waves. The shielding of all these waves contributes to the attractive forces too for the sake of symmetry of the whole model
Dec 26, 2011
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The matter we are made of, can hardly have moved 13.5 billion light years over 13.5 billion years, just as light has done it?
There is something rotten in the state of the Universe. (Adapted from William Shakespeare's "Hamlet")
Big Bang is the evil uncle who try to defraud Hamlet, by using machinations and not acknowledged lies.
Dec 26, 2011
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I think you need to revisit the idea of what 'expansion' actually means. That should clear up your confusion.
Dec 26, 2011
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Dec 26, 2011
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Matter hitches a ride on spacetime.
The current state of the U is unknown and unknowable. The only thing we can observe is what happened in the past. As for the present we just have to use our imagination.
Dec 26, 2011
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Dec 26, 2011
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Well maybe maybe not. I've been seeing something about spacetime expanding only between elements of matter. So molecules, for example, would hold together no matter how much spacetime expanded. I'd think not. In which case molecules would dissociate as matter expanded. Maybe even atoms would fall apart. Interesting.
Dec 27, 2011
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Dec 27, 2011
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Atomic/electromagnetic forces do not get weaker because of the expansion of space - so the distance of atoms to one another will stay the same (i.e. any expansion within an atom/molecule will immediately be 'rectified' by the (sub)atomic particles moving back to the equilibrium positions of all the forces acting on them).
Dec 27, 2011
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http://www.aether...hism.gif
In linearized, EinsteinMaxwell theory on flat spacetime, an oscillating electric dipole is the source of a spin-2 field, i.e. gravitational waves or graviton flux
http://rspa.royal...987.full
So I presume, in hyperdimensional Einstein's field theory the rotating massive body would generate the spin-1 field, i.e. the flux of photons. Maybe the Hawking radiation of black holes is such a field actually, if we imagine, beneath the event horizon there are many wildly moving singularities (which would appear like galaxies in our generation of Universe).
Dec 27, 2011
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http://arxiv.org/abs/1011.4956
The AWT explains it with dispersive nature of Hubble red shift - only waves/objects smaller than CMBR field appear expanding, the waves/objects larger than CMBR field appear collapsing instead. After all, the ripples at the water surface are doing the very same.
http://www.aether...ples.jpg
The trick is in the point, we are observing the expansion of Universe from inside above CMBR wavelength scale, so it appears like contraction instead. The entropic time arrow does the very same and it switches its sign around CMBR wavelength scale.
Dec 27, 2011
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What does that even mean? Are you making things up again?
So? There is a thing called gravity. Ever heard of it?
Remember: Stuff coalesced into matter some time after the big bang.
That elecrtromagentism is very strong dos not mean it is stronger than anything at all. Given enough energy it can be overcome (and at the big bang enough energy was to be had in abundance)
Dec 27, 2011
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The similar effect we can observe inside of dark Alexander band between primary and secondary rainbows during heavy rain, where the dense rain droplets become similar to foam with both positive, both negative curvature in similar way, like the density fluctuations of vacuum (CMBR noise). The dark band corresponds the empty cosmic space after then, the rainbows correspond the objects smaller and larger than rain droplets.
Dec 27, 2011
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Dec 27, 2011
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Ah. So you're just making stuff up. Thought so.
Dec 27, 2011
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It's just Big Bang theory, which is forced to making stuffs up - not me.
Dec 27, 2011
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You may believe it or not - but this is exactly the prediction of dense aether model, which still waits for its confirmation. For example, in the last year the US astronomers announced surprising results from a high-altitude balloon experiment called ARCADE-2, which had made careful measurements of the sky at radio wavelengths. The background radio emission, which is the component smoothly distributed across the whole sky, was six times brighter than anyone was expecting.
Dec 27, 2011
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Dec 27, 2011
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http://arxivblog.com/?p=335 http://arxiv.org/abs/1007.1750 http://arxiv.org/abs/1009.0953
Is the universe really expanding? http://www.aether...ette.pdf
Did the Universe Have a Beginning?
http://www.metare...ning.asp
Dec 27, 2011
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Whereas the mild proponents of new ideas face mild negativism of many people, the strong proponents of new ideas are coupled with strongest opponent in 1:1 ratio similar to pairing of particles and antiparticles inside of boson condensate.
Dec 27, 2011
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Dec 27, 2011
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Again same question: Does AWT assign an electro-magnetic component to gravity? YES or NO. Forget all this other stuff for the moment, we can get into that later.
Dec 27, 2011
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The objects will not move in space, it is the space that is expanding. That's the truth.
But is it the truth about the universe or is it just a theory? A theory there only tells us that we humans know nothing about, but so very like to want to believe.
One is what science people think and say, but something quite different is how the universe manifests itself.
The universe does exactly what it wants and does not ask us humans permission to do what it is doing.
Do not science people to gods who think they know the truth about the universe. For do you so, you will do science to a religion and science is not a religion.
Remember, science people say they only know of less than 5% of all the universe is composed.
If you know less than 5% of something, you know almost nothing about it.
And that is truth. Believe it or not.
Dec 28, 2011
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Dec 28, 2011
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Dec 28, 2011
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http://www.aether...hism.gif
So that the answer is: "YES, but in limited extent". For example, gravitational waves, if exists apply to higher number of dimensions, than the electromagnetic waves. So that the gravity laws can describe gravitomagnetism with vortex field in 4D, but I'm not sure about gravity waves. There is definitely certain similarity, but every theory which will use this similarity too literally will be wrong. You'll need substantially higher number of dimensions to reconcile the gravity theory and EM theory, then the number of dimensions in which these theories operate by now.
Dec 28, 2011
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Dec 28, 2011
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All those math courses I took to get my Engineering degree, and now I find out once I get beyond Earth's orbit they no longer mean anything. Okay GR & QM, move over, the mathlessness of a new "wave" proposes to engulf astro-physics to placate the mathematically challenged.
Dec 28, 2011
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It's not so bad. We are random fluctuation of it and we can observe it in transverse waves at two zones corresponding the energy density / distance scale of atom nuclei and the stars composed of atom nuclei.
http://www.aether...cale.gif
It means, the application scope of general relativity and quantum mechanics is limited to two zones of dimensional scale and the rest of Universe must be described with less or more ad-hoced extrapolations of these two theories. Outside of these limits the Universe is indeterministic and random and the low dimensional deterministic models become poorly conditioned there.
This problem may be solved conceptually easily with introduction of additional dimensions into existing theories, and the string theory is the another step in this direction (actually Heim's theory was really first hyperdimensional theory).
Jan 01, 2012
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Previous posts indicate its primary purpose is to irritate the mainstream physics community.
My view is that all matter and (force) fields are the result of some particular configuration (curvature) of spacetime, either at the macro or quantum scale. At the quantum scale only certain configurations are allowed. I don't buy the idea about two zones of dimensional scale at about 2cm as if the CMBR has some particular wavelength. I'm also having problems with the idea of a dimensional scale. I should hope dimensions would be scalar invariant.
Jan 02, 2012
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Actually I think surviving electrons aggregate in an inner shell in the denser parts of spacetime where their gravitational attraction is balanced by their electrostatic repulsion. Positrons are similarly configured in an outer shell where their gravitational attraction balances their mutual repulsion. Note positrons are not attracted by gravity until spacetime expands so much that its energy density is less than that of the positron's. Well I can get into more cyclic U theory but I think that should be enough conjecture for right now. Except for one thing: If expansion reduces the curvature of spacetime and gravity I should think it would reduce all other forces so if any molecules should escape the black holes they would fall apart. But I still have some more thinking to do on that one.
Jan 02, 2012
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Well how could I do that? According to Newton's second law as long as there is a force acting on something it will accelerate. So if the U is expanding because of some force then it will continue to accelerate. I assume there is some force out there (the quintessential 5th force) causing expansion - the internal energy of spacetime. This force acting over a distance performs work. Work requires energy - the dark energy I presume. If this energy is finite then accelerated expansion will stop when the energy runs out. At this point the temperature of the U will probably be near zero and the attractive electrostatic forces which I discussed in the previous post will take over.
Jan 02, 2012
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Jan 02, 2012
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So we should believe whatever gives us self-assurance and don't ask questions. Sounds sort of like feel-good religion.
Wow. You're way ahead of me on that one. I'll have to check it out. It does seem a bit off-topic though.
Did I say something about that? Sorry. BTW are you promoting the idea of static spacetime?
Jan 02, 2012
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Certainly not. The closer particles come the greater the force of gravity between them. If the expansion force of spacetime was greater than gravity I'd be flying off my chair right now.
Jan 02, 2012
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The matter here was formed here, it hasn't moved (other than some minor local proper motion). The matter "over there" which emitted the light from the most distant galaxies we can see was formed "over there", it hasn't moved either. The gap between "there" and "here" has increased during the time the light was travelling.
No, only in your understanding of it. ;-)
Have a Happy New Year.
Jan 02, 2012
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I think Calippo was referring to the early inflationary period suggested to explain the uniformity of the CMBR. The details of that are not yet understood.
Jan 02, 2012
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I know the explanation, but the problem is. The space where our matter is located, has expanded at a lower speed than light has traveled by. The light can probably not come rushing after the expanding space.
We can hardly be in an expansion by a speed greater than the speed of light. Are we that, we would not be able to see the young universe.
Jan 02, 2012
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Jan 02, 2012
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I think we would if we were traveling right along with the expanding U. Anyway I did my homework tonight and found per http://en.wikiped...universe the current radius of the U is 14 mpc which would represent an expansion speed for the farthest reaches of the U of about 1/3 the speed of light assuming the Hubble constant is 71km/sec/mpc. But I don't provide any assurance of getting correct results for freebie consultation services.
Jan 02, 2012
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Jan 03, 2012
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of universes, so exact similar scenarios must occur multiple times, in fact, an infinite number of times. So we have an indeterminate fraction of this possiblity - infinite/infinite. In this case I'd have to pull out Occam's razor and say why would nature want to repeat the same scenario? So no I don't think there are exactly repeating scenarios, if that's what you mean by evolution.
Jan 03, 2012
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You cannot meanignfully describe expansion by a speed without reference to the distance, think of it as a fractional change, for example Hubble distances have increased by about 1% in the last 200 million years.
That is exactly what it does. From the point of view of the galaxy from which the light was emitted, we are moving away and the light is chasing after us. If you imagine the space between filled with specks of dust,the light passes each at speed c.
What you mean is not clear to me but we can see out to a redshift of about 7 and the distance between us and a galaxy at a redshift of about 1 is increasing at one light year per year.
Jan 03, 2012
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That should be 14 GPc, not MPc.
It isn't that easy because the Hubble constant was much higher in the past (it is only constant over space, not time) and the source galaxy was much closer.
Jan 03, 2012
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Jan 03, 2012
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Actually the shells idea comes from my take on the images seen by Penrose and company in the CMBR.
Jan 03, 2012
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Density is energy divided by volume so "less density than spacetime" is not a phrase that means anything to me.
The distribution of matter and antimatter would always have been uniform everywhere, there are no "fringes of space". Many tests have confirmed the Cosmological Principle.
Again that makes no sense, positrons and protons are positive while electrons and anti-protons are negative so why would they repel?
The rings reported in the CMBR are not shells, they would be like ripples in a pool but recent checks have pretty much ruled them out as statistical artefacts.
Jan 03, 2012
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http://www.univer...ventory/
Bedtime for me now...
Jan 03, 2012
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Jan 04, 2012
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Jan 04, 2012
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Jan 04, 2012
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So nature shares her secrets with all observers in the U. It's amazing what you can see by just looking.
Jan 04, 2012
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Jan 04, 2012
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Jan 04, 2012
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Jan 04, 2012
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but... I thought the expansion rate was increasing at an accelerating rate? I was only intending to calculate the expansion rate at the present time.
Not sure what that means.
Jan 04, 2012
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Jan 04, 2012
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Google came up with "Aether Wave theory" for AWT so I guess that's what you mean. I hadn't heard of it before and I've been studying cosmology for more than a decade (just as a layman though). From what I've read today, it's just crank nonsense.
I was talking of simple compression waves in the hydrogen/helium plasma that radiated what we see as the CMBR. If Penrose's observations had been correct, that is what they would represent.
Jan 04, 2012
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Expansion has been known about since the late 1920's and Hubble's observations and it was assumed that it would be decreasing due to gravity as you say. At the end of the 1990's new telescopes allowed Perlmutter to measure supernovae at much greater distances and to everyone's surprise he found the expansion was speeding up. Textbooks give us maths which can describe that depending on the cause:
Jan 04, 2012
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http://en.wikiped...smology)
If the cause was some form of energy distributed throughout space which became less dense as space expands, w would have the value -1/3 and the acceleration would slow but would have been higher in the past. If on the other hand it comes from an intrinsic property of the vacuum, then as space expands, each cubic metre always generates the same effect. In that case w=-1 and the expansion increases exponentially.
The data from the WMAP probe combined with other measurements has tied down the value fairly accurately in the last few years:
http://en.wikiped...d_models
w = -0.980 /- 0.053
It looks very strongly as though w=-1 is right.
Perhaps it will help if I point out it is the same as the energy behind the Casimir Effect which has been measured in the lab:
http://en.wikiped...r_Effect
Jan 04, 2012
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That should read w = -0.980 plus/minus 0.053
so between -1.033 and -0.927 with 68% confidence (1 sigma).
It seems to be impossible to get the plus sign into the page!
Jan 04, 2012
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The light was emitted a long time ago.
It is, but the Hubble constant is the ratio of speed to distance.
The rate of expansion is currently about 1% per 200 million years, but you can't express that as a speed without selecting a distance and the light wasn't emitted here so what does your 300c mean?
To get the speed of the source, you need to multiply the distance to the source when the light was emitted by the Hubble Constantat that time, not now. Both are varying.
Jan 04, 2012
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Jan 04, 2012
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Actually, the probability is about 100%, that's the problem with their claim. For example see this summary of the criticisms:
http://www.nature...665.html
or here
http://telescoper...niverse/
There will be a lot of traffic but basically, they misunderstood the statitics of the CMBR, the circles are entirely expected in the randomness and mean nothing.
Jan 04, 2012
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Jan 04, 2012
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Sounds like if somebody gave you this assignment they made an excellent selection.
Yes we have some (or maybe a) proponent at this site.
Jan 04, 2012
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The light there was sent out at the dawn of time, just after the Big Bang, that light, we will never ever come to see, because that was sent out at a time when our particulate matter were very close to all the other particulate matter, who sent the light. The light has long since left us and would never ever come back again. There is a limit to how far back after the Big Bang we can see light coming from. This limit is hundreds of millions of years and therefore also light-years.
Therefore the universe can not be a big bang created universe and expands. We see precisely the light coming much too far away.
Jan 04, 2012
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As to the question of whether these circles are statistically significant I'd like to see any other similar or other unique patterns existing in the CMBR. But even if they're not statistically meaningful they apparently do exist and fit my ideas about their purpose.
Jan 04, 2012
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If the circles actually don't exist we would have a case of fraud and I don't think Her Majesty would be very happy about that. She has another more serious problem on her hands right now. BTW thanks for the links.
Jan 04, 2012
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My point exactly. But I still don't see the colliding black hole idea as being very plausible.
"It is, however a clear prediction of conformal cyclic cosmology." I like this idea on fermions but not about infinite expansion.
Jan 04, 2012
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OK,but why not calculate 140 GPC or 1400 GPC, it's just an arbitrary number. Just because that material happened to emit some light a long time ago which we can see now doesn't make it special other than for us.
Jan 04, 2012
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No, somebody posted a link to the article in a cosmology forum on Facebook and I just thought I'd respond to some of the misunderstandings
http://www.facebo...7490267/
Jan 04, 2012
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The farthest we can see using EM (light) is the CMBR. Using mean figures, that has a redshift of 1090. It was emitted 378,000 years after the start at a distance of some 41 million light years from us. It was at a maximum distance of about 6 billion light years from us about 9 billion years ago because the space between us and it was expanding faster than it was moving towards us. After that though, as the Hubble Constant reduced, it was able to catch up to us. You can work it out on a simple spreadsheet.
Jan 04, 2012
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One of the subsequent papers searched for perfect equilateral tringles and found several. Pick a shape and it's probably there. That's the problem, the statistical nature of the CMBR means false detections are highly likely. I'll try to find a reference tomorrow to another paper I know of which is much more professional and virtually rules out such signals.
Jan 04, 2012
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You're previous link to the article in Nature has a link to this paper by Moss et al: http://arxiv.org/...05v3.pdf
Two additional critiques of the original Gurzadyan and Penrose paper ( http://arxiv.org/...3706.pdf ) are also noted:
http://arxiv.org/...56v1.pdf
http://arxiv.org/...68v1.pdf
A response to these critiques has also been posted: http://arxiv.org/...1486.pdf
For myself I'm still not convinced of the significance of G & P's "discovery" and, as the Nature article points out, even Gurzadyan admits "....he is not prepared to state that the circles constitute evidence of Penrose's model. "We have found some signatures that carry properties predicted by the model"".
Jan 05, 2012
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Jan 05, 2012
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I misused the term, but note Fleetfoot points out the exponential distribution of space expansion. So perhaps spacetime and its energy density is also exponentially distributed.
Yes I think antimatter has less energy density than matter but all objects in spacetime seek regions of space having a similar energy density, meaning antimatter in less dense regions and matter in more dense regions. Like a submarine diving or surfacing. Or so it would seem.
Jan 05, 2012
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Jan 06, 2012
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That might work if the noise spectrum were flat but it is far from it:
http://map.gsfc.n...dex.html
The peaks mean there are intrinsic resonances which will create patterns. Since there may be non-linearities involved, it is possible that peaks of a fundamental could coincide with those of its harmonics which would approximate conentric "families". The analysis needs to take that into account and so tests will be much more complex. For example considering whether the commonality of the centres of circles with harmonically related radii is more than would be expected given the power spectrum.
Jan 06, 2012
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Yes, it assumes the CosmologicalPrinciple:
http://en.wikiped...rinciple
It is hard to test homogeneity radially but many tests have confirmed that the universe is isotropic from our location so that reduces the assumption to the Copernican Principle:
http://en.wikiped...rinciple
If the principle applies now then expansion is also isotropic so it would apply at all times, past and future of course.
Jan 06, 2012
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No, I said the rate becomes exponential as the matter becomes very dilute, the distribution is isotropic.
Equivalent matter and antimatter particles have the same mass.
Neither has an energy density on its own. Mass is one form of energy and energy density is just the total mass divided by the volume in which it is found. Just add up all the mass you find in one cubic metre of space, multiply by c^2, and you have the energy density. You need to average over many clusters of galaxies in cosmology of course.
Sorry but that's nonsense, energy density is an average over a large volume.
Jan 06, 2012
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Jan 06, 2012
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Alas, as I see it each element of spacetime has a nominal energy (call it E) and a nominal energy density, but quantum fluctuations move the borders around between adjacent elements. You can get off at this STOP if you never heard of quantized spacetime. Hence quantum fluctuations are fluctuaions of energy density. If these fluctuations form one of the configurations allowed by QM or string theory or whatever they become locked in by gluons (think of them as elements of a template) to form a particle-antiparticle pair.
Jan 06, 2012
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So the uncertainty principal robs Peter to pay Paul in the sense that it moves the borders so initially if Peter and Paul each occupied a volume of 2, say, the quantum fluctuations move the border between them so now Peter occupies a volume of 1 and Paul a volume of 3. Same total energy (2E), same total volume (4), just a bit of energy density redistribution you might say. So now Peter has an energy density of E/1 (E) and Paul E/3. Voila. Paul gets the short end of the stick. He will have to move into a neighborhood with lower energy density and Peter will get promoted to the higher density neighborhoods (like a black hole, the poor sucker).
Jan 07, 2012
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Neat site. I got the red line covered except for a little red uptick on the far right end.
Good points. You would need to know the expected value at each pixel and calculate a variance around those expected values.
Jan 07, 2012
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Jan 07, 2012
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Fine but Peter might be a proton or anti-proton while Paul is the electron or positron, it still wouldn't differentiate matter from antimatter, only families of particles.
No, the nearest low-density region is Paul so they would just revert to the original configuration, winking back out of existence as QM says.
Jan 07, 2012
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There's a button to force the concordance values so you can see what you missed.
Using known pixel values assumes the result so instead they
use a Monte Carlo technique to create random maps with the same angular power spectrum and then see how many circle patterns their analysis gives. If the real data shows more than is statistically predicted, then they might have a significant result. Others have done that and the circles seem to be noise.
Jan 07, 2012
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Sure but to separate antimatter galaxies from matter galaxies, you've got to move them over astronomical distances. We know there is virtually no antimatter within our Hubble sphere.
Jan 07, 2012
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http://aetherwave...ter.html
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Don't bet the farm on it.
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Been swimming lately? How far down can you dive?
Jan 07, 2012
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Yes it does seem simple but you have to read the fine print.
Actually I meant diving. Another situation where your ears might pop.
Jan 07, 2012
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Which fine print do you mean? I'm not swimming, neither diving, neither see some fine print. What's the actual purpose of your sixty four posts in this thread? IMO you're just daydreaming loudly.
Jan 07, 2012
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The post about the force of gravity being greater than the force of expansion.
If we didn't have to re-hash the same arguments over and over there wouldn't be so many posts.
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Jan 09, 2012
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Because we don't see a huge gamma flux which would result from any significant amount of antimatter.
I don't understand the rest of your comment, anti-neutrinos are commonly produced in particle accelerator experiments and "we" certainly consider them to be antimatter.
Dark matter cannot be neutrinos because they don't have enough rest mass though something like a heavy neutrino is a candidate. Dark matter forms clumps and structures whereas neutrinos with negligible energy move close to the speed of light.
Jan 09, 2012
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A box one cubic metre containing Peter and Paul would have the same energy content as the same box empty. Put an electron or positron in it and the energy is increased by 511kEv. I'm not sure what your are suggesting but if I take what you say literally, it doesn't work.
I've realised there has been some confusion because we are using "energy density" in two different ways. In this argument, you seem to use the term to mean the vacuum energy whereas on cosmological scales it refers to the contents of space which create gravitational effects, the two are not the same. That has probably caused some miscommunication previously.
Jan 09, 2012
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My mistake, I meant the observable universe.
The quantity is completely negligible in comparison to the mass of the Solar System and that is typical. Cosmic rays produce small quantities but it is not a significant fraction of the mass of the universe in terms of gravitational effects.
Jan 09, 2012
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In some accelerators, protons are collided with anti-protons to double the energy available. If the energy of the antiproton was negative, it would reduce the total instead of increasing it. Positive energy means positive curvature so antimatter is identical to matter gravitationally. It's not been confirmed experimentally yet but the success of the group who stored anti-hydrogen for over 1000 seconds last year means it should soon be possible.
Jan 09, 2012
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A positively charged black hole would attract electrons and repel protons and vice versa for a negatively charged BH. Either way, the charge tends to get neutralised. The radiation pressure is far more significant (and not affected by charge) so accretion disc dynamics is a very complex subject.
Jan 09, 2012
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This is where you are confusing energy densities. The total mass of matter (including dark matter but not dark energy) in the observable universe is constant so as it expands, the density falls as you say. That density generates the curvature called gravity so that too falls.
On the other hand, the vacuum energy in any given volume of space is not dependent on scale factor, it appears as an intrinsic property of space, so it is constant (this is what you described with "Peter and Paul"). Since it acts like a repulsive component of gravity, as the universe expands to the point where they effects are equal, the expansion stops slowing and then starts to accelerate. that happened about 7 or 8 billion years ago.
Jan 09, 2012
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Matter and antimatter contribute identically, both produce the same gravitational effects. The red tick is at the upper frequency limit or equivalently at the limit of resolution of the sensors. The Planck spacecraft is intended to improve that end of the graph:
http://en.wikiped...cecraft)
Jan 09, 2012
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The usual WMAP image is a Mollweide Projection of the CMBR. The pattern certainly relates to the large scale struture "out there" but it is a surface which is a sphere centered on where we are and always have been.
On the other hand, blobs in the image will have formed into galaxies now 45 billion light years away and scientists in those galaxies will see their CMBR coming from the plasma that later cooled and formed into our galaxy.
As Edwin Harrison said:
Hydrogen is a light, odourless gas, which, given enough time, turns into people."
Jan 10, 2012
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Unless the vacuum produces enough of a quantum fluctuation so that spacetime can intervene and separate the particle pair to become real particles, they will remain as virtual particles and merge back into the vacuum. So if matter and antimatter didn't react opposite to each other in the presence of spacetime, there would be no pair production.
Jan 10, 2012
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Jan 10, 2012
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That's what I said. As you described your idea, the energy in each region doesn't change, only the size, so put a box round both of them and it contains the same total energy as the empty box. Either that or I misunderstood your explanation.
Jan 10, 2012
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Correct, other than normal dynamic processes, it remains unchanged.
No, an observer far from the galaxy sees it getting farther away but remaining the same size.
Jan 10, 2012
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It is hardly surprising, stand in a field on a foggy day when visibility is 100m and the region you can see is a circle of 100m radius centered on you. Move 50m away and the region can see is still a circle of 100m radius centered on your new location. The CMBR works the same way, everyone in the universe can see light that has been travelling for no more than the age of the universe no matter where they are.
Jan 10, 2012
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"it expands" in the context of the quotes means space. This was covered some time ago in thread, rulers are bound by EM forces so don't change.
Jan 10, 2012
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Jan 10, 2012
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No, what it means is that the contribution from vacuum energy stays the same over time, hence it is a "Cosmological Constant". That doesn't mean it produces no effect, it produces a constant effect.
Jan 10, 2012
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Exactly.
No, it is caused by the energy density itself, not a difference.
You just agreed that "antimatter is identical to matter in energy content" so put each in a 1 cubic metre box and the energy density is the same too, trivially. For example, whether you put an electron or a positron in a 1m^3 box, the energy density is 511kEv / m^3.
Jan 10, 2012
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There is no significant amount this side of the CMBR which means virtually nonw within a sphere of 45 billion light years radius from our location.
The variation in the CMBR which you see in the maps is a few parts per million. That means the energy density doesn't vary by much more than that anywhere within 45 billion light years of here. Your speculation doesn't match reality in the slightest.
Jan 10, 2012
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I understood Aether theory didn't have a model, what is it's replacement for the Friedmann Equation?
The hydrogen absorbtion lines, mostly Lyman-alpha and beta, from the neutral gas during the dark ages produce the Gunn-Peterson trough:
http://en.wikiped...n_trough
We can still see through the universe at other wavelengths.
In the big bang model, the universe can be either finite or infinite. We can't say which applies as yet (and may never be able to), but certainly it is much bigger than the region we can observe.
Jan 10, 2012
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http://en.wikiped..._Way#Age
http://wiki.answe...a_galaxy
If the Universe emerged from singularity, then these galaxies should be nearly as distant, as the oldest galaxies inside of Hubble deep field. Which they indeed aren't and they even moving toward each other, so they're expected to collide in next few billions of years. One must be very strong supporter in Lambda-CDM/Big Bang model for to believe such a situation would be possible in it.
Jan 10, 2012
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Questioning the Big Bang http://arxivblog.com/?p=335
Evidence Against the Expanding Universe Hypothesis http://www.etheri...ift.html
Jan 10, 2012
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Exactly, as you say it deescribes the expansion of the universe, so if you don't have a big bang model, the question remains, what is your aether-based alternative?
It means that a significant part of the hydrogen was neutral before a redshift of roughly z=6 after which it was almost entirely ionised. The first stars switching on just prior to that is the conventional explanation of course.
Go ahead then, explain your alternative.
Jan 10, 2012
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The article is wrong. In fact I did some work on the Pioneer anomaly and just out of curiosity considered the effect of expansion. The sign was wrong of course, it would produce a redshift instead of the observed blue, but the effect is only about an order of magnitude less than the "anomaly" so could be measured locally with a carefully designed mission of the type that Turyshev was suggesting.
Jan 10, 2012
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Why are you misquoting? The first says the best fit is 12.6 for the Milky Way and the second 13.2 for Andromeda, perfectly normal values. They give one star as 14.0 but with an uncertainty of 2.4.
Where did you get that nonsense?
So? Most galaxies everywhere are probably around 10 to 12 billion years old, they all started forming around the same time because conditions were the same everywhere. You seem to have a bizarre understanding of the model.
Jan 10, 2012
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Oh dear. Q2 from your first link:
"The microwave 'background' makes more sense as the limiting temperature of space heated by starlight than as the remnant of a fireball."
Wrong. The CMBR is a nearly perfect fit to a black body while a distributed source would give a near flat (or exponentially decaying) tail, the integral of a black body over here to infinity.
From your second link:
"The main problem with the Big Bang theory is that the cosmic background radiation does not have the characteristics youd expect ... the radiation curve has the distinct whiff of a black body about it, ... Most theorist do not imagine the Big Bang like this."
ROFL, the source was hydrogen/helium plasma at 2790K and a redshift of 1090, a black body is exactly what we expect.
Jan 10, 2012
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True, but I claim they don't come in same size boxes. Remember when I was talking about Peter and Paul they both have the same energy but quantum fluctuations caused a difference in volume between them (during pair production) with the total volume remaining the same, Peter getting the short end of the stick, or less volume. Same energy but different energy/unit volume.
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Jan 11, 2012
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Right but that variation is representative of the variation of density on that spherical surface and an observer say 5 billion light years away would see the same which means it is also representative of the variation of the density throughout the volume bounded by that sphere.
Jan 11, 2012
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I can calculate how much energy is is any sized box and for any given size, the densities are identical.
You miss the point though, in your description, the total energy is the same as a vacuum while we know real matter particles have non-zero mass. Your visualisation doesn't reflect that at all.
I remember that well, but a few posts farther on you now say that was wrong and the energy in each region is zero!
Jan 11, 2012
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ROFL, you forgot what this article is about even though you are responding to it.
Here's another:
http://www.physor...ies.html
The paper you quote is seven years old, the technology and our knowledge have moved on a very long way in that time.
Jan 11, 2012
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"It" means your idea. Note in the original post you quote here, you said each volume had an energy of 2E in contrast to your more recent post.
The bottom line though again is that you need 511keV of extra energy compared to the vacuum for an electron or a positron. If Peter and Paul and an electron and a positron then you need 511keV for each, a total of 1022keV, not zero.
Jan 11, 2012
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There might still be a graininess but according to a professional in the field, after the Integral result was announced, there was the sound of many papers on string theory being shredded. To put it in context, the maximum grain size is probably contrained to be 13 orders of magnitude less than the Planck size.
Anyway, the way you are thinking about it doesn't work as I mentioned earlier. You might be interested in this though:
http://www.newsci...ime.html
Jan 11, 2012
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Sure, and it is no doubt still emitting, it'll just be a long time until that light gets here (if ever).
The Andromeda Galaxy is 3 million light years away so we see it as it was 3 million years ago but of course it is still there and still shining. The same is true of the matter which emitted the CMBR but it has now become galaxies and they are about 45 billion light years away. Scientists there will have a view little different from ours.
Jan 11, 2012
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I didn't miss it, they are fundamental particles so have no internal parts needing to be bound together :-)
Jan 11, 2012
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That's different, they had 2E last time ;-)
No, the mechanical distortion of the divder holds the energy, not the empty spaces.
That's because they aren't made from a group of quarks :-)
http://en.wikiped...particle
Jan 11, 2012
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He called it his "biggest blunder" but ironically the latest measurements of expansion suggest it is a perfect match for the acceleration.
You are half right. It looks very likely that it is vacuum energy (as tested in the lab by the Casimir Effect) but because it acts like a negative pressure and force times distance is work done, that negative work cancels the additional kinetic energy of the matter so overall it conserves energy.
Jan 13, 2012
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Jan 14, 2012
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Jan 14, 2012
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Throw an object in the air and it first rises, then stops, then falls back to Earth. If you plot a graph, the curve is quadratic. Reverse the time axis and the curve is the same shape, the object still accelerates towards Earth so gravity is still attractive. The same argument applies to the repulsion of two electrons.
Jan 14, 2012
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That is part of it but gravity results from the "stress-energy tensor" which includes pressure as well as energy. The negative pressure part does negative work so overall the result is that no energy is needed if the effect is as given by Einstein's Cosmological Constant" (CC). If the effect varies with time (called "quintessence") then that may not be true.
As I said some time ago, the equation of state for the CC is w = -1 and the current best measurement is -0.980 give or take 0.053 so it's looking very much as though a CC is right.
http://en.wikiped...d_models
Jan 14, 2012
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Work done is certainly energy lost by the worker but gained by the visible U.
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The trick is during inflation the distance from particles was very small so all matter created during inflation almost instantly came into gravitational communication with each other. And they remain in instantaneous communication unless they are accelerated. Point being if we expect to find gravitational waves from distant objects which we can see these objects and their gravitational fields have long since departed their positions where we now see them. But we can pick up gravitational waves from objects that we are now in communication with and we will know their presence long before we can see them. An amazing new possibility for astronomy - know the universe as it is now, not billions of years in the past.
Jan 14, 2012
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As for the antimatter floating away - it propagates an anti-gravitational field. These neutralize normal matter gravitational fields so matter doesn't interact with antimatter as long as there are intervening elements of spacetime between them. Matter pulls on elements of spacetime and antimatter pushes on elements of spacetime, and without this intervening spacetime the particle-antiparticle pair annihilates. So much for quantum gravity.
Jan 15, 2012
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Jan 15, 2012
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Yes, a simple example would be if quintessence was substance, its density would fall with time and so would its effect.
Jan 15, 2012
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If the pair is an electron/positron for example, they wouldn't "float away", their charges mean they are strongly attracted.
This might help:
http://en.wikiped...oduction
"These pairs exist for an extremely short time, and mutually annihilate in short order. In some cases, however, it is possible to boost the pair apart using external energy so that they avoid annihilation and become real particles."
The pair themselves have only energy "borrowed" from the vacuum and cannot exist with momentum and duration more than that given by the uncertainty principle
http://en.wikiped...rinciple
Jan 15, 2012
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Sorry, that should have read ".. exist with energy and duration .."
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Note the idea of an outer shell being say anti-matter and the inner shell matter would be consistent with the idea of anti-matter occuping more volume than matter and thus having less energy density.
Jan 16, 2012
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Jan 17, 2012
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Positive mean density for the matter in space means positive curvature regardless. If the vacuum also has a mean density then that contributes too. In GR, all forms of energy and pressure (and the cosmological constant) contribute so it is possible to get a flat universe even with positive matter and radiation densities. A good analogy is the skin of an orange, galaxies create dimples but they don't define the overall shape.
Jan 17, 2012
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If they can get energy from some other source, then there is usually enough to separate them, but you can't say the amtimatter "drifts", both particles must move off with equal and opposite velocities to conserve momentum.
Jan 17, 2012
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That seems to make no sense. Put your finger over the end of a bicycle pump. Push the handle down half way and you double the density of the air in the cylinder. Since e=mc^2, you have also double the energy density, it certainly isn't constant and I can't see what that has to to do with gravitationally bound groups of objects.
Jan 18, 2012
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Jan 18, 2012
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If it is an even tighter limit then there will be more fodder for the shredders :-)
I haven't had a chance to read the paper yet and the limits are in different units so I can't say if this cites and supersedes the Integral result.
Jan 18, 2012
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I mean I can't see why you think gravity has any relevance to the energy density of a substance, for example that of air in a bicycle pump.
We can talk about short range gravity versus the cosmological constant separately but you seem hung up on densities so I'm trying to understand what you are thinking in that regard.
Jan 18, 2012
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Jan 21, 2012
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That doesn't really work. First, gravity exists within the universe, it's more like the Van der Waals forces between the air molecules in the pump. Second there is no outside from which the contents can be drawn.
Good point, the question of entropy in cosmology is quite complex and still a puzzle.
Going back to the previous posts though, there is no link between the fact that the Milky Way galaxy is a gravitationally bound collection of stars doesn't affect the density of the air in my bicycle tyres so I still think you are conflating unrelated concepts.
Jan 21, 2012
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Compressed air is intended to represent matter, which I model as some form of compressed spacetime. Else where does matter come from? It's only one possible configuration of spacetime.I see spacetime as being outside matter similar to atmosphere outside the airpump. Spacetime and matter are made of the same stuff, just like air in the pump and the atmosphere are made of the same stuff.
Jan 21, 2012
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Jan 21, 2012
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Sorry I stole your stuff. Can't seem to get it into high gear tonight. Must be all that snow shoveling. I agree your idea about galaxies and air in the tires seems to be a bit quixotic. Wow I never used that word before. Wonder how it will work.
Jan 21, 2012
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Sounds too much like AWT to me. Don't take it personally though.
Jan 21, 2012
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http://www.aether...memo.gif
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Jan 22, 2012
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"Matter" is one classification of energy.
OK, I had read your post to mean that the contents of the universe had been pumped in from somewhere else, my mistake.
If that's how you look at it, there isn't a problem. Whether particles are compressed spacetime or not, they have energy and momentum and that's all we need to consider. The term energy density is the amount of energy per unit volume averaged over any arbitrary region of space. It includes all forms of energy so the nature of the particles is irrelevant.
Jan 22, 2012
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Yes, that would have been clearer. You then have one value for the density of the vapour which should be the same everywher. The water density in the form of drops however can vary from region to region as they may clump together or forms voids between clumps due to their random motion.
Jan 22, 2012
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No, just trying to remove the confusion over the meaning of "energy density", it was getting in the way of the dicussion.
True but I didn't think that was relevant for the analogy. Laying aside your model, pumping up the tyre also heats the gas:
E=mc^2
The mass is also greater when the compressed air is still hot and reduces as heat is lost through the walls of the tyre. It both weighs more and creates more gravity when hot. Not only that, the pressure itself also creates gravity. The source is the stress-energy tensor and the "stress" part is the pressure.
Jan 22, 2012
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Jan 22, 2012
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Where are the calculations showing that? I have seen many people make claims for their aether models but not one of them has ever actually had a theory when pushed, it has always been just talk and wishful thinking.
Jan 22, 2012
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The underlying idea of AWT is, the Universe is random material stuff and the people are one of its fluctuations which interacts with the another ones through transverse and longitudinal waves in similar way, like the soliton at the water surface. Despite you're believing in this model or not, it's evident, too large or too small objects will appear for such fluctuation like the indeterministic noise. If you cannot realize it, then you cannot deduce anything from AWT, derive the less.
Jan 22, 2012
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Jan 22, 2012
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The underlying idea of AWT is ...
Analogies are only useful for communication and discussion which and for that yours was better.
In science though a theory must make quantitative predictions and that is where the aether concept failed. The basic luminiferous aether was indistinguishable from SR in that it resulted in the same Lorentz Transforms but was entirely phenomenological and couldn't explain gravity. The claims you are making are completely baseless.
This is rather strange because I an arguing for gravitational substantivalism in another forum which is probably closer to an aether theory than anything you can offer.
Jan 22, 2012
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No. The energy density of the spacetime (i.e. the vacuum energy) outside and inside is the same, only the matter is being compressed. This is where you are confusing the terms.
Pressure is force per unit area and force is rate of change of momentum. Flow of momentum is a surce of gravity and it is the change of momentum of the particles that generates the gravity. The spacetime has nothing to do with it.
Jan 22, 2012
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Right, they are the microscopic and macroscopic views of the same thing. The masses of the particles don't change of course.
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Jan 23, 2012
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Time is what stops everything happening at once, space is what stops everything being in one place. Matter needs spacetime to keep it apart. Similarly, it is very difficult to define the metric of spacetime without having a sprinkling of matter in it which can be measured. They are distinct but interdependent so I wouldn't disagree with what you say above.
Where you are getting it wrong though is trying to use the difference in densities. Relative to the critical level needed for the universe, dark energy contributes 72%, dark matter 23% and visible stuff about 4%. The total is the sum of those parts, not the difference.
Jan 23, 2012
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This is probably the mostly widely referenced page on the concept and the "Hole Argument" against it:
http://plato.stan...holearg/
There is a much shorter blog post introduction here:
http://www.andrew...ism.html
Le Sage's gravity was grossly flawed, it would produce drag on planets unless the particle speed was far higher than the speed of light, and the heating effect would vaporise a planet in a fraction of a second unless the speed was very low. The model could only approximately reproduce Newtonian gravity and we now know that is wrong anyway.
I'm afraid not, Le Sage was always unworkable.
Jan 23, 2012
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Newtonian gravity is only a good approximation for weak fields, Le Sage shares its limitations but also fails for reasons I gave before. GR has never been found to be wrong at any scale above QM. If you want an alternative, try TeVeS:
http://en.wikiped..._gravity
Actually, as far as I can gather, there is no such thing as "AWT", just a lot of talk about ideas but no maths that could be tested by making quantitative predictions so no "theory" in the scientific sense.
Jan 23, 2012
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Jan 23, 2012
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Jan 24, 2012
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The higher the speed, the greater the problem of heating.
Gravitational waves travel at the speed of light in GR but wouldn't exist in Le Sage's gravity (same as Newton).
Le Sage's gravity is the same as Newton's, it was just an attempt to find a mechanism for his "action at a distance".
Of course we have, General Relativity replaced Newtonian gravity almost a century ago. The inverse square law is wrong, you have to use tensors to get it right.
Jan 24, 2012
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What I have said is all textbook stuff and complies with all the laws of physics. Your misunderstanding comes from your bizarre idea about "compressed spacetime".
Our best measurements say the universe seems to be flat which means the total energy should be zero (or very close to it). The gravitational potential is negative so you need positive energy from the contents to have a total of zero. The inventory I quoted is from this article:
http://www.univer...ventory/
It's worth reading the "technical note" at the bottom which explain why they are percentages.
Jan 24, 2012
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Jan 24, 2012
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The difference refers to the reconfiguration of spacetime. This requires compression, expansion, twisting, or whatever else happens to change it. It might even mean severing elements of spacetime and trapping them in some otherwise empty volume. Anyway apparently the total volume of spacetime is conserved (ergo "flat").
Here's a theory: The existence of fields is because spacetime has memory. That memory makes it possible to set up vibrations or static fields. Your music instrument strings wouldn't vibrate unless they remembered where they were before you plucked the string. Actually mostly this is just theory until I find something more plausible either in the textbooks or in the imagination[;)
Jan 24, 2012
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Jan 24, 2012
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What you are missing is that gravitational potential energy is negative:
http://en.wikiped...l_energy
All the stuff in the universe started close together so the potential was very negative. Making the gravitational potential might seem arbitrary because it is a gauge but consider the virial theorem:
http://en.wikiped..._theorem
A good example of its use is in globular clusters. If the total kinetic energy of the stars is E, the total gravitational potential energy is -2E and the system is bound because the total is less than zero. The same rule works for individual planets too.
Jan 24, 2012
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You might also like to check the Physics FAQ:
http://www.phys.n..._gr.html
In particular, note near the bottom:
A flat universe has exactly the critical density, one electron more and it is closed. As the article says, it is hard to prove the total energy is zero but it is asymptotically close to it.
Nah, that's only an idea. If you had a theory, you could write down its equations and show they match all current observations ;-)
Jan 24, 2012
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Note including spacetime.
Jan 24, 2012
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Jan 24, 2012
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Jan 25, 2012
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Uh-oh. Sounds like a guy I used to jaw with about gravity, I think it was.
Wow. Now that makes 2 guys who know where I live. Double scary.
Jan 25, 2012
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No credit to me, as I said, it's all basic textbook stuff.
It balances all the forms of energy, see the detailed inventory I cited before.
No, gravity is what we call the effect of the resulting distortion of the geometry of spacetime.
Again, see the detailed inventory I have cited several times. It's a UniverseToday article with links to the original documents.
Jan 25, 2012
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I used that as an example explaining why gravitational potential energy is taken as negative. In that case, it only relates to the kinetic energy of the stars, not the E=mc^2 internal energy.
For the universe overall though, the total negative energy does balance the total positive energy. Here's the link again:
http://www.univer...ventory/
Jan 25, 2012
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Jan 26, 2012
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All you missed is that dark energy is on the same side of the balance as all the other contributions.
We know how much energy there needs to be overall to make the universe spatially flat. Of that amount, dark energy is 72%, dark matter is 23%, intergalactic plasma is 4% and all the rest constitute less than 1%. What suggests we are on the right track is that the total is 100% to within the accuracy of the measurements.
Jan 26, 2012
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Jan 29, 2012
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As I said before, it balances the overall negative gravitational potential energy AIUI. For a closed universe, the Hamiltonian is zero and the flat universe is asymptotically close to closed. Here's the FAQ article again:
http://math.ucr.e..._gr.html