Statistical modeling could help us understand cosmic acceleration
December 24, 2010 By Miranda Marquit
(PhysOrg.com) -- While it is generally accepted by scientists that the universe is expanding at an accelerated rate, there are questions about why this should be so. For years, scientists have been trying to determine the cause of this behavior. One of the theories is that dark energy could be the cause of cosmic acceleration.
In order to test theories of dark energy, a group at Los Alamos National Laboratory in New Mexico and the University of California Santa Cruz came up with a technique designed to test different models of dark energy. We are trying to investigate what could be behind the accelerated expansion of the universe, Katrin Heitmann, one of the Los Alamos scientists tells PhysOrg.com. Our technique is based on data, and can be used to evaluate different models.
Heitmann and her collaborators created their method based on Gaussian process modeling; the implementation was led by Tracy Holsclaw from UC Santa Cruz. Were using statistical methods rather than trying to come up with different models. Our process takes data from different sources and then uses it to look for certain deviations from what we assume in a cosmological constant. The groups work can be seen in Physical Review Letters: Nonparametric Dark Energy Reconstruction from Supernova Data.
Many scientists think that dark energy is driving the accelerated expansion of the universe, Heitmann says. If this is the case, it is possible to characterize it via its equation of state w(z). The redshift evolution of the equation of state parameter w(z) would show some indication of a dynamical origin of dark energy.
Heitmann points out that in such a case, there could be an infinite number of models. We cant test all those models, she says, so we have to do an inverse problem. We have data and we can characterize the underlying cause of the accelerated expansion. It assumes that w is a smoothly varying function, and a dynamical dark energy theory would fit that. We can use data and analyze it to see if we can find indications that dark energy really is behind accelerated expansion.
The Los Alamos and University of California, Santa Cruz team first tested their statistical technique on simulated data in order see whether the method was reliable. After we saw that it was, Heitmann says, we tried it on currently available supernova data.
So far, their analysis has not revealed that a dynamical dark energy is behind the accelerated expansion (the cosmological constant is a very special case of dark energy and is still in agreement with the data), but Heitmann doesnt think that means that the door is closed on dynamical dark energy theories as the cause of acceleration in the expanding universe. The data so far is limited, and better data is coming in every day, she says. Additionally, the group hopes to include other data in their statistical analyses. Our technique allows for the input of data from cosmic microwave background and baryon acoustic oscillations as well, and thats what we want to add in next.
If this technique does identify a dynamical dark energy as the reason behind accelerated expansion of the universe, it could mean revisiting the basics of what we know about the workings of the universe. If we do find the time dependence that supports the idea of dark energy as this mechanism, then we can go back to the theory approach. We would have an idea of which models could better explain universes expansion history and ultimately develop a self-consistent theory with no ad hoc assumptions.
More information: Tracy Holsclaw, Ujjaini Alam, Bruno Sansó, Herbert Lee, Katrin Heitmann, Salman Halbib, and David Higdon, Nonparametric Dark Energy Reconstruction from Supernova Data, Physical Review Letters (2010). Available online: http://link.aps.or … t.105.241302
Copyright 2010 PhysOrg.com.
All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.
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Dec 24, 2010
Rank: 1.6 / 5 (20)
Dec 24, 2010
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Dec 24, 2010
Rank: 3.6 / 5 (11)
It might not be a coincidence. That is, it may be a consequence of the universe's density, and it may be that a "goldilocks era" for intelligent life to arise is also a consequence of density. Or anyway, that a third variable effectively causes both.
Dec 24, 2010
Rank: 4.9 / 5 (17)
According to wiki article, acceleration of expansion began about 5 billions years ago, not few thousand years.
http://en.wikiped...universe
Dec 24, 2010
Rank: 1.3 / 5 (23)
Dec 24, 2010
Rank: 1.4 / 5 (11)
Dec 24, 2010
Rank: 1.4 / 5 (19)
Yes, it's called the "big crunch".
The universe is not collapsing, because if it were everything would be blue shifted. The fact everything is red shifted, in every direction, with the exception of a few objects within the local group, means that it's almost certain that everything is moving away from everything else, UNLESS there is some form of "tired C" explanation.
The big bang theory is based on the false assumption that you can run the laws of physics backward indefinitely. However, even the physicists themselves admit tha tisn't possible because it contradicts themselves. So then they had to introduce the theory of an inflationary period in which the laws of physics didn't exist and matter could move faster than light, in order to explain how objects in the universe could move 26 billion ly distant to one another (13 billion in all directions).
Dec 24, 2010
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Dec 24, 2010
Rank: 1.2 / 5 (19)
1) The universe is not collapsing.
2) The big Bang theory is not falsifiable.
3) The big Bang Theory is not internally consistent, i.e. self contradicting, because it is based on the notion of running physics backward till you get to an origin, but then when they realized it doesn't work they changed the "laws" of physics to try to explain it.
If the laws of physics can change, then for all we know, they could have changed 10,000 years ago, and could even change all the time. Moreover, this is absolutely no more or less absurd than the inflationary theory aspect of the Big Bang.
Dec 24, 2010
Rank: 1 / 5 (18)
Anyway, if science is only about what is "falsifiable" then the big bang theory should be immediately discarded by anyone who calls themself a scientists or a science enthusiast, because changes in the laws of physics are not falsifiable. You can never actually prove by any means when and where the change actually happened.
Either they know this and are intentionally lying about it, or else they don't know this, and are therefore not qualified to be in the discussion.
I mean think about it. Let's say the function "y = f(x) = 3x+4" represents the laws of universe, and we are at x = 100. If law has changed sometime in the past, when? You can't subtract from X because you don't even know if the past used same function.
Dec 24, 2010
Rank: 1.3 / 5 (19)
Maybe it was all of them, or maybe it was none of them.
Ya'll can mock me all you want, but the entire science of cosmology, as it regards the Big Bang theory, TOE, and String Theory, is a completely irrational, self contradicting logical fallacy.
Dec 24, 2010
Rank: 4.4 / 5 (7)
I think Roger Penrose has a somewhat similar idea, but the difference is his works on there being no matter. At maximum entropy when the universe consists of nothing but photons, essentially big becomes small. Since photons don't really move from their own perspective due to relativity they all exist in the same point, which happens to be the only point. Then some magic and there's another big bang or whatever.
Dec 24, 2010
Rank: 1.1 / 5 (18)
Let's say I have a watch, and it represents universe. The hands represent time and laws of universe. We can run hands backwards for ever and ever, as though running laws of physics backwards forever. Indeed, they go around and around as ong as you care to wind it backwards, analogous to 13billion years back time, or even infinite regression, but at the end of the day watch was made in 1995...
Regression fails, whether the laws of physics or constant or not, it is not reliable to find age or initial condition of a system over ridiculously long time when dealing with cosmology or creative event.
Dec 24, 2010
Rank: 4.8 / 5 (17)
Dec 24, 2010
Rank: 1.6 / 5 (20)
1) You clearly miss the point of my argument.
2) You also miss the point of the fact that the regression now assumes a change in the laws of physics. Read up on the big bang and "inflation".
3) It is not reasonable. The reality is no amount of regression is falsifiable.
Look at the watch example, and imagine a tiny elf lives inside the watch. Elf does and regression and concludes, "Because I can imagine running hands backwards forever, the universe must be infinite," or else, he picks an arbitrary number based on some misunderstanding of a gear or cog, and says, "It was made in 1990!"
Little does he know, "Made in 1995" is written where he can't see it.
Such is the problem of "falsifiably" determining the origin of a system from inside the system...
Dec 24, 2010
Rank: 1.2 / 5 (25)
Idjits. If laws of physics can change once, then how do you know they haven't changed a billion times in the past second?
I win this debate. You fools are just too stupid to realize it.
Big Bang is not falsifiable, therefore not scientific.
Get over it.
Dec 24, 2010
Rank: 2 / 5 (4)
Dec 24, 2010
Rank: 5 / 5 (12)
The watch analogy fails because this watch does not collapse in upon itself as you dial back time.
As for the "bozos" you speak of, I imagine that the combined academic careers of hundreds of scientists amounts to at least thorough 'thinking through' of the models.
Dec 24, 2010
Rank: 4.8 / 5 (17)
The fact that this is a scientific theory means that it must be falsifiable. BBT makes all kinds predictions from nucleosynthesis (and ratios) of light elements to the cosmic microwave background to the morphology and distribution of galaxies and quasars and a prediction of cosmic neutrino background.
That last prediction still hasn't been totally confirmed due to the difficulty of detecting these low-energy, ghostly particles, but there is indirect evidence for them.
Those are awfully big predictions and if any of those pillars were observed to be wrong, it would falsify the theory as it stands, so your comment is blatantly wrong (like most of them).
Dec 24, 2010
Rank: 4.8 / 5 (16)
The laws of physics do not change in the Inflationary model of the Big Bang. The universe expands at a great rate, but no matter is set into motion faster than the speed of light; within any given cosmic horizon, nothing is violating the SOL. If you understood the theory, you'd see it doesn't imply changing laws of physics. There's no reason to consider it unfalsifiable.
Dec 24, 2010
Rank: 1 / 5 (15)
then you still miss the point.
If the laws of the universe can change, then you cannot assume they haven't changed recently. You cannot dial back the universe at all, not even conceptually, because if the laws can change, then you can't know what laws it was following and when.
If they laws can change once (inflation,) then how do you know they didn't change yesterday?
If the laws have changed once (inflation,) then how do you know they haven't changed two or more times?
How would you even detect a change in the laws that occured yesterday, or the day before, or 10,000 years ago? You can't, and yet you equally cannot prove it didn't happen, and that is a problem for cosmology.
You can't prove the laws are constant, its axiomatic. in fact they as much as say they aren't now.
But then if the laws change, you can't prove they didn't change very recently.
Dec 24, 2010
Rank: 1.2 / 5 (20)
BS and more bs. Read up on different aspects of big bang inflation period, you lie, or else just don't know what they say.
Violations of conservation laws are allowed, some physical and quantum quantities are said to be meaningless, etc.
By any reasonable definition that is changes in the laws of physics.
This is why I get so annoyed with people on this forum. It's the same old crap. You people even lie about what you claim to believe, as widely recorded in encyclopedias, physics text, and journals.
It's sad that it's the same thing with mainstream. Say one thing, then lie about what you just said
Dec 24, 2010
Rank: 1 / 5 (16)
How can you actually prove that without a time machine?
HOw can you prove everything wasn't created "as is" just a short while ago, with all quantum matter and energy in place and all light from all sources already where it is? Without a time machine, you cannot prove or disprove.
Dec 24, 2010
Rank: 1 / 5 (18)
Maybe the type 3 aliens are all moving their galaxies to another part of the universe to look for a new place to colonize. Maybe they are trying to get as far away from humans as possible.
This explains the red shift without the need for "dark energy".
By Occam's razor this is a better theory because it is falsifiable (eventually,) and it doesn't make up pixie dust or change the laws of physics to explain anything.
Dec 24, 2010
Rank: 5 / 5 (14)
Great argumentation
We have, Have you?
Which conservation laws? Who allows them?
Which ones? In what context? The only thing that's meaningless is your blathering.
I've not seen uyou provide any definitions, reasonable or otherwise.
Why? Because most make sense and take the cranks to task?
Alas, true.
Still waiting for some references in support of whatever you're trying to say.
Ah, there it is - the evil mainstream, a crank's last refuge!
Dec 24, 2010
Rank: 5 / 5 (3)
Dec 24, 2010
Rank: 5 / 5 (6)
Ok, I did. Here's one example of something I read:
http://www.astro....re26.pdf
Dec 24, 2010
Rank: 1 / 5 (3)
If it walks, flys, & quax like a duck: Its a Focking Duck !!! Its time to surrender to Occam, accept the CC as DE, & move on.
Dec 24, 2010
Rank: 1 / 5 (2)
Dec 25, 2010
Rank: 4.2 / 5 (5)
I kept expecting to see somebody shoot you down, and was disappointed that nobody had. Then I reread and found them and saw that you were just shouting the same blather over their responses. Figure it out yet? Care to point out how/what laws of physics were "changed" during the inflationary period?
Jimbo, what are you talking about? Also, TH is at BSE - AM and Stat.
Dec 25, 2010
Rank: 5 / 5 (5)
It is a consequence of more space, not increasing hubble constant. Altough the constant could still change a little, it is called a constant only because of tradition.
For example during inflationary period, hubble constant was many orders of magnitude larger. Maybe currently observed small hubble constant is some remnant of this primordial expansion?
Dec 25, 2010
Rank: 4.5 / 5 (15)
No, that's ridiculous jsut as your other assertions are.
You really don't seem to understand even the most basic postulates of Relativity if you think something like this is more reasonable than "this is the way the universe works, and here's the math to show it"
Dec 25, 2010
Rank: 3.5 / 5 (16)
Dec 25, 2010
Rank: 3.2 / 5 (13)
No wait- I'm the center of the universe, I forgot-
Dec 25, 2010
Rank: not rated yet
Dec 25, 2010
Rank: 1.3 / 5 (13)
If there is a light horizon determined by 72km/s/megaparsec, and it's the same in every direction, then for all practical purpses we in fact ARE at the center of the universe.
Divide speed of light by 72km/s, then multiply by megaparsec, which is 3.6 million ly, then you get EXACTLY 15 BILLION LY.
Now if there is event horizon 15 billion ly in every direction, then we in fact are the center of the universe, and it doesn't even matter if we move. The space-time warps proportional to how far we move, so that horizon is always the same distance in every direction.
Geocentric model is wrong, but it doesn't even matter, because the light horizon is the same distance from the earth no matter where the earth moves. Remember in relativity space-time is warped to compensate for motion.
If you do lorentz transform for length contraction of v=30km/s and apply it to radius of universe, it shrinks by 0.7ly.
Dec 25, 2010
Rank: 1.3 / 5 (14)
Critical thinking. Learn some guys, it'll help in life.
Dec 25, 2010
Rank: 5 / 5 (5)
The "time" the acceleration appears to have started was several billion years ago, more or less; a significant percentage of the apparent age of the Universe. Not last week, last month or last millennium.
Dec 25, 2010
Rank: 4.4 / 5 (7)
Time and Space are equivalent. Hence, time started when space started
Occam's Razor would be a good place for you to start.
Dec 25, 2010
Rank: 5 / 5 (6)
Evidence for dark energy has been found independent of observations of type Ia supernovae:
http://en.wikiped...k_energy
http://en.wikiped...e_effect
Dec 25, 2010
Rank: 4.8 / 5 (35)
Dec 25, 2010
Rank: 2 / 5 (3)
Dec 25, 2010
Rank: 4.8 / 5 (38)
Dec 25, 2010
Rank: 4.6 / 5 (11)
I see you're not answering any questions, but cranking some more, which is expected. The universe has no true center of course, as every point is moving away from every other point (at large scales), so you could pick any point, Earth, Mars, M87, whatever, and say it's the center, as everything is moving away from that point too.
Dec 25, 2010
Rank: 2 / 5 (8)
Dec 25, 2010
Rank: 1.6 / 5 (7)
Dec 25, 2010
Rank: 5 / 5 (15)
True.
True.
Apparently? Really? Says who? And what does the BB model have to do with that ridiculous assertion?
Hardly. You seem to have forgotten, or are unaware of, the fact that light travels at a finite speed. The deep-field galaxies that we see (and they would see of us) are as they appeared billions of years ago, and not as they are now (like our galaxy is to us).
Get thee to a schoolery!
Dec 26, 2010
Rank: 1.7 / 5 (6)
Yes. And we don't see all of what is within the light horizon. I have serious doubts about expansion theory, but it is of no consequence. I would like to see more investigation concerning the 'well accepted' theory of expansion. Since we understand so little about the energy/matter of the universe as we see it, I'd like to see some serious consideration given the red shift and it's cause. Could all that matter/energy we can't see or even define have some effect on the wavelength of light?
Dec 26, 2010
Rank: 4.6 / 5 (11)
If you were familiar with the geometrical postulates of relativity and it's relation to the recursive analysis of the expansion of the universe you'd know that all points in the universe are the center. We're not moving away from anything, nor is anything moving away from us. Everything is simply expanding.
Dec 26, 2010
Rank: 3 / 5 (2)
Dec 26, 2010
Rank: 4.5 / 5 (8)
Dec 26, 2010
Rank: 5 / 5 (4)
The problem is objects outside of *our* light horizon may be inside the horizon of objects within our light cone. So while it is an indirect relationship the observable universe is still influenced by the (indirectly) unobservable universe.
Dec 26, 2010
Rank: 1 / 5 (8)
Agreed, what is observed contradicts the Big Bang theory. What we observe is near uniformity in every direct when we look out into the universe. The universe appears to be flat. So why do we still believe in the Big Bang theory instead of an infinite universe in age and size when that is what we observe? What is more believable, the magic of an inflationary period or some other explanation for the red-shift we observe?
Dec 26, 2010
Rank: 4.3 / 5 (13)
Inflationary BBT is the current standard model of cosmology because it fits all observations and thus far nothing has refuted it.
Dec 26, 2010
Rank: 1 / 5 (13)
Dec 26, 2010
Rank: 1 / 5 (11)
Dec 26, 2010
Rank: 4.3 / 5 (11)
Dec 26, 2010
Rank: 1 / 5 (11)
And secondly what needs explaining about energy and, or matter inflating (traveling) at a thousand or more times the speed of light during the inflationary period? Its a violation of one of the most fundamental laws of physics.
Dec 26, 2010
Rank: 1.7 / 5 (6)
Exactly. The inflationary period is proposed as an theory because it is the only explanation (yet) in spite of the fact that it violates all we understand about physics. It's like 'god' ... unprovable. It either was or it wasn't and we will probably never know. As I said earlier, we just don't know enough to be arguing about the problem. Studying it, yes. Discussing it, yes. Arguing... no.
It is like arguing about what is at the bottom of a black hole. No one is ever going to go there to find out. Well, save the minds of science fiction writers.
Dec 26, 2010
Rank: 4.8 / 5 (40)
False. During the inflationary period nothing travels FTL, as nothing travels THROUGH space FTL,... spacetime itself expands do to vacuum energy. This is in line with GR.
Dec 26, 2010
Rank: 4.8 / 5 (38)
... The universe (spacetime) can expand FTL during the inflationary period as long as no "information" travels FTL. There are epiphenomenon in electrodynamics where some wave travel FTL, but cannot be used to convey information, so is not in violation of known laws of physics.
Dec 26, 2010
Rank: 1 / 5 (11)
So what you are claiming is that the value of space time inself changed during the magical inflationary period?
Dec 26, 2010
Rank: 4.9 / 5 (30)
How do you figure?
Define what you mean by "value of space time".
Dec 26, 2010
Rank: 1 / 5 (6)
Dec 26, 2010
Rank: 1 / 5 (10)
Well it is unbelievable because the matter and, or energy inflated during the inflationary period had to carry information because how else could anything follow the end of the inflationary period?
Dec 26, 2010
Rank: 4.6 / 5 (9)
Dec 26, 2010
Rank: 4.6 / 5 (10)
Very muddled and confusing statement. I take it all you're stating is a rough approximation for the speed of light in a vacuum - okay...
Again, your language is poor so it's hard to know exactly what you're trying to argue. First, matter and/or energy didn't inflate. The vacuum did. Because the universe was much smaller pre-inflation, all of its parts were in causal contact (ie, there was information exchange). Post inflation, the parts that were in causal contact were exponentially expanded to all 'corners' of the universe we can see today, which is why the universe appears flat, homogeneous and isotropic.
Dec 26, 2010
Rank: 1.5 / 5 (8)
The question will likely never be answered. How did everything we percieve and even guess about come from, essentially, a singularity? Science uses 'inflation' to explain what it currently perceives as the current state of the universe. NOT the actual state, but the one that science theorizes exists. The theory of inflation is simply science's current best guess as to the origin of the universe. They might as well say that god did it.
It us useless to argue the 'unbelievability' of it since it is only theory and will very probably never be substantiated in any meaningful way.
You need to remember that this is all about something that cannot even be estimated as to size. And the age is just a guesstimate.... er theory.
Dec 26, 2010
Rank: 5 / 5 (10)
Yes, it's a difficult question to answer, which makes the effort to find those answers so rewarding.
And what is the ACTUAL state? Do you know? Science can never confirm the actual nature of reality, ever. We just know what works with observations.
No, it's the best guess as to what happened AFTER the origin of the universe.
(continued)
Dec 26, 2010
Rank: 5 / 5 (10)
Are you daft?
It is useless trying to make the universe conform to your idea of believability - the universe doesn't care. Gravity is only a theory too, do you choose to believe in it?
Unintelligible.
For the love of...
Dec 26, 2010
Rank: 1.9 / 5 (9)
Neutron star =(emits)=> Neutron
Neutron =(decays)=> Proton & Electron =(combines)=> Hydrogen
Volume(Hydrogen)/Volume(Neutron) = 1,000,000,000,000,000
See: www.youtube.com/w...=related
Dec 27, 2010
Rank: 1.4 / 5 (10)
No, I'm not daft. Extreme science, such as the cosmology dealing with the universe (whatever it is) is akin to religion. There is nothing that can be proved, just supposed.
It (cosmology) does provide satisfatory employment for numeous Phds, and so is a good thing. Yet whenever I see the high priests of cosmology expressing their 'knowledge' of the universe as factual, I harken back to my days in catholic school. (shudder)
No, at close range, we understand the working of chemistry and physics and can test our theories in a lab. Cosmology will never be tested in a lab or observed at close range. In fact, cosmology has no importance to human life, except that of producing wonder.
omatumr: The local 'universe' also contracts as the group of local galaxies swoop ever closer to each other. I do admit that that is a 'wonderful' benefit!
Dec 27, 2010
Rank: 5 / 5 (10)
Let's see...
What's 'extreme' science? Science is science.
You're losing your opening defense already. Science is the EXACT opposite to religion. That you don't grasp that and are trying to equate the two does not bode well for your defense.
Patently untrue. Many predictions have already been confirmed by observation. There are still unanswered questions, true, but the pursuit of answers to those questions is what's exciting.
Careful, you're starting to register on my Crank-o-meter.
Dec 27, 2010
Rank: 5 / 5 (10)
What's at fault are your perceptions of what is being said, or perhaps you're getting your info purely from pop-sci articles which usually murder the topic being discussed. The fact that you use phrases like 'high priests' in connection with science adds another notch on the Crank-o-meter.
How close is close range? What is the cutoff point?
Dec 27, 2010
Rank: 5 / 5 (10)
I guess they're wasting their time at the LHC reproducing quark-gluon plasmas as existed millionths of a second after the big bang. And with desktop black hole analogs and magnetic monopoles in spin ices and at the NIF and...
The universe doesn't contract locally, it simply follows the laws of gravity. I'd say you have failed in your defense. Guilty as charged!
Dec 27, 2010
Rank: 1 / 5 (4)
Dec 27, 2010
Rank: 5 / 5 (3)
Dec 27, 2010
Rank: 5 / 5 (5)
Theory is useful because a good one can make accurate predictions.
The mathematics behind humanity's best theories describe dependent quantities in ways that hold true in experiment and observation
i appreciate the added understanding i have gained from most of you.
the rest of you... thanks for the entertainment.
Dec 27, 2010
Rank: 5 / 5 (1)
i hadnt heard of this. i thought the CMBR was the very most redshifted light in the known universe. Can you post a link to some source of info about long waves gaining energy (blue shifting)?
Dec 27, 2010
Rank: 5 / 5 (2)
maybe they are not the same person, but came from the same school or whatever. hmmm...
Dec 27, 2010
Rank: 5 / 5 (8)
Don't hold your breath, given the author of the quoted post.
Absolutely. Your last quotation came from the sockpuppet master himself, who has tens if not hundreds of aliases.
Dec 27, 2010
Rank: 1.8 / 5 (8)
You are confusing the expansion of the universe with the inflationary period. They are two entirely different things.
Dec 27, 2010
Rank: 2.5 / 5 (2)
From a historical perspective it's the other way round:
First the observation of an universe which appears flat, homogeneous, and isotropic. Without any physical understanding why this would be so.
Then the invention of inflationary models. They were invented just for the sake of answering the questions raised by the observation of a universe that appears flat, homogeneous, and isotropic.
They are based on a theory which upto now has not been falsified and, therefore, is a valid one. This theory, unfortunately, has no basis in particle physics upto now.
Dec 27, 2010
Rank: 4.4 / 5 (7)
Dec 27, 2010
Rank: 3.3 / 5 (7)
True, it is believed today that the universe is expanding at an ever accelerating rate but this expansion has absolutely nothing to do with or in common with the inflationary period.
The universe expanded at a 1000 or maybe a million time the speed of light during the inflationary period immediately following the BB.
The reason or explanation for these two expansions are even different. They answer two different problems we observe when looking out into the universe.
Dec 27, 2010
Rank: 5 / 5 (6)
Our understanding has changed...and will change. Dark matter, inflation, etc are all things that are refinements of an internally consistent and robust predictive tool that scientists use. When the predictions don't fit observations, we must go back and look at assumptions of the model and change it.
CP violation is not a broken law of physics...it is something that we cant explain at the moment. The constant comments that X, Y or Z is NOT falsifiable are laughable. We really can't say one way or another. The revolution of the Earth around the Sun may have been impossible to falsify at one time, but our tools and theories improved. There is so much yet to be discovered...
Dec 27, 2010
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Dec 27, 2010
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Dec 27, 2010
Rank: 2.8 / 5 (6)
And yes, during the inflationary period the universe did expand 1000's of times the speed of light.
Dec 27, 2010
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Then it would still be occuring, at a far greater rate, currently. We have no primary indication that the expansion of spacetime has ever slowed. We have indication that expansion within the observable universe is increasing.
That by virtue of science only allows for a few potentials without evidence, primary of which is that expansion never slowed down. The only reason for the postulation of exponential spacial increase then a slowdown is to address the causality problem.
Dec 27, 2010
Rank: 2.7 / 5 (7)
(quote from link below)
The Inflation Theory proposes a period of extremely rapid (exponential) expansion of the universe during its first few moments. It was developed around 1980 to explain several puzzles with the standard Big Bang theory, in which the universe expands relatively gradually throughout its history.
http://map.gsfc.n...nfl.html
Dec 27, 2010
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Dec 27, 2010
Rank: 1.7 / 5 (6)
http://blog.hassl...fect.pdf
The blue shift is not the only effect observable here
http://arcade.gsf...006.html
Dec 27, 2010
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http://www.spacer...id=14524
Dec 27, 2010
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Dec 27, 2010
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The idea of multiverses, for instance, is not falsifiable as Ethelred, one of the most reasonable users here, is the first to concede.
And the realm of Planck units is far from being measurable, thus all statements wrt this realm remain speculation for the foreseeable future.
It is not forbidden to venture into speculations as a scientist, but in order not to become a nutcase it is essential to always be aware on which side one is walking.
Dec 27, 2010
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Dec 27, 2010
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Agreed that the statement is too general. But while I would concede that measurements of the Planck realm are not possible now, they may be in the future by way of other observations (cosmic background, vacuum particle creation, or some completely "unrelated" area of physics or astronomy).
My general point is that we are all too quick to say something can't be tested (implying "ever").
But yes, we should be clear whether or not something is speculation, hypothesis, or theory. In general, i think scientists don't convey this well to the general public, or the public doesn't understand the distinctions and agree that we should be aware of, and clearly convey what side we are describing.
Dec 27, 2010
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http://www.physor...ses.html
It may just be possible to observe things we thought were unobservable.
Dec 27, 2010
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Dec 27, 2010
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beelize54:
What? Why should inflation violate Copernican principle?
Dec 27, 2010
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http://www.entang...ple.html
I can accept, we cannot see further because of event horizon of Universe - but why to assume, inflation occurred just before this horizon a few millions years earlier?
Dec 27, 2010
Rank: 4.3 / 5 (6)
False, he's quite correct there was a period of "super-inflation" followed by continued inflation at a MUCH reduced speed.
http://hyperphysi....html#c5
Dec 27, 2010
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Dec 27, 2010
Rank: 4 / 5 (6)
Well it's simply the accepted theory. I'm actually surprised you don't know this already.
Far be it from you to admit you're wrong though...
Dec 27, 2010
Rank: 5 / 5 (4)
I'll recant, but not without a good bit of complaining about it. As entanglement is getting closer and closer to becomming falsifiable, closing the loopholes, I reserve judgement as well.
Dec 27, 2010
Rank: 5 / 5 (7)
Providing a link to 'scientific' articles on theological websites rather trashes your credibility. The author of the article is Nicholas Knisely a Dean of Trinity Episcopal Cathedral in Phoenix AZ, who moved to Phoenix from Bethlehem PA where he was the Rector of Trinity Church in the city of Bethlehem.
But even if we look beyond the religious inspired spin, Knisely's thesis is based around a real scientific proposal made recently to try to explain DE and lithium abundances by suggesting that the universe is not homogeneous on the very largest scale. Instead, we may be sitting at the center of some kind of giant void in a much larger universe.
Unfortunately, that assumption has since been shown to be false. And in any case, it had nothing to do with inflation, per se.
Dec 27, 2010
Rank: 2.3 / 5 (3)
False, he's quite correct there was a period of "super-inflation" followed by continued inflation at a MUCH reduced speed.
Again, show the observational evidence. (I'd say prove it, but there is no method by which to do so.)
Well it's simply the accepted theory. I'm actually surprised you don't know this already.
Everything discussed in this thread is theoretical.
Dec 27, 2010
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Dec 27, 2010
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What?
The article you referenced stated that they had witnessed galaxies present when the universe was three to six billion years old. Do you when the inflationary period occurred? It took place less than the tiniest fraction of a second after the universe emerged from a singularity.
Dec 28, 2010
Rank: 3 / 5 (4)
"The article you referenced stated that they had witnessed galaxies present when the universe was three to six billion years old. Do you when the inflationary period occurred? It took place less than the tiniest fraction of a second after the universe emerged from a singularity."
What you might have gleaned from the article is that scientists were surprised that their calculations were not correct. Reality vs mathematics. Reality won.
Dec 28, 2010
Rank: not rated yet
When the universe was extremely small there would be practically no space in which to expand if the rate had not changed over time.
When universe was 1 cubic centimeter expansions was minute (x*y+z) then when universe was 2 cubic centimeters expansion would be at least double (2x*y+z).
Now (some enormous amount of time later) we have to take into account compound effect in reverse or we get wrong answer for birth of universe.
Dec 28, 2010
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Dec 28, 2010
Rank: 2.9 / 5 (7)
That is the problem.
Oliver K. Manuel
Dec 28, 2010
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Dec 28, 2010
Rank: 3 / 5 (2)
Mkay. What's your point? Evolution is a theory too, does that mean you don't point out a person's error when discussing the theory?
Dec 28, 2010
Rank: 1.8 / 5 (6)
Why thank you for that semantic nonsense fraj. The words super and extraordinary, and expansion and inflation are indeed different words...
...just like idiot and moron. Those are what we call synonyms in English. Since English isn't your native language I thought I should point that out to you...
Dec 28, 2010
Rank: 1.5 / 5 (8)
No. Neutron repulsion is based on experimental data of ~3,000 nuclei with two or more neutrons.
Neutron repulsion is observed as an increase in rest mass (E = mc2).
To see the data for yourself, Google:
"Attraction and repulsion of nucleons: Sources of stellar energy", Journal of Fusion Energy 19, 93-98 (2001).
"Neutron repulsion confirmed as energy source", Journal of Fusion Energy 20, 197-201 (2003).
or the video: "Scientific Genesis 3. Neutron Repulsion"
Oliver K. Manuel
Dec 28, 2010
Rank: 4.2 / 5 (5)
Beyond the fact that you cite primarily your own work with no interaction from others, and that your models are contrary to observations and spectro-data.
Do you actually have any experimental evidence of neutron repulsion within a stellar core? Do you have any method of testing this or observing it in nature?
You're aware that the mass balance of the Universe requires Hydrogen to be the most abundant element, and this heavy to light model you're suggesting would result in a Universe that is trillions of years old and collapsing?
Dec 28, 2010
Rank: 1.8 / 5 (4)
Do stars explode?
Is the Sun generating H by neutron decay?
Is matter fragmenting at the center of galaxies?
Nuclear rest mass data leaves no reasonable doubt about neutron repulsion.
Here are a few additional references:
3. "The Sun's origin, composition and source of energy"
arxiv.org/pdf/astro-ph/0411255v1
4. "Superfluidity in the solar interior: Implications for solar eruptions and climate," arxiv.org/pdf/astro-ph/0501441v1
5. "Composition of the solar interior: Information from isotope ratios,"
arxiv.org/pdf/astro-ph/0410717v1
Oliver K. Manuel
Dec 28, 2010
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Dec 28, 2010
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Ethelred
Dec 28, 2010
Rank: 4.3 / 5 (6)
I take you don't like the theory of a strong force. Or the weak force either. And are you ever going to discuss the iron stack in India?Yes see it. Its funny. Typical Crank video. Has no evidence to support Oliver except the same crap he always posts. His own papers that show the weak force is involved.
SHHe could look at the data from the stack of iron that was in India. He won't even acknowledge that it ever existed.
Ethelred
Dec 28, 2010
Rank: 5 / 5 (5)
I'm pretty sure nothing can travel faster than light through space. I don't know any rules about how fast space itself can expand into nothingness. I'm no expert, but even the relative distance between objects in space during this expansion wouldn't be moving faster than light since the masses are not being accelerated. The space between them is being stretched,which once again does not contradict your C speed limit. Oh, star trek warp drive, I will one day have you. QC, are you favoring the steady state universe?
Dec 28, 2010
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Dec 28, 2010
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Dec 29, 2010
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Dec 30, 2010
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Dec 30, 2010
Rank: 2.8 / 5 (4)
The Universe appears to be expanding. This expansion produces a red shift in the light that is traveling towards us. This MUST be lowering the energy of the light. That energy must go somewhere. Space-time stretches out the light, looking at the symmetry of the situation that implies that the light must stretch out space-time. Thus the electromagnetic radiation of the Universe may be the cause of the expansion of the Universe. So it would be LIGHT Energy and not dark.
I posted this before, I wrote it slightly differently, but no one commented on it. I would like to know if anyone else thinks it has merit or am I just Cranking.
Ethelred
Dec 30, 2010
Rank: 1 / 5 (3)
Ethelred, in my opinion there is no chance - absolutely none - that you will ever grasp why the universe expands if you refuse to consider neutron repulsion or the nuclear rest mass data that reveals it.
1. "Attraction and repulsion of nucleons: Sources of stellar energy"
Journal of Fusion Energy 19, 93-98 (2001).
2. "Nuclear systematics: III. The source of solar luminosity",
Journal of Radioanalytical & Nuclear Chemistry 252, 3-7 (2002)
3. "The nuclear cycle that powers the stars: Fusion, gravitational collapse and dissociation": arxiv.org/pdf/astro-ph/0511379v1
4. "On the cosmic nuclear cycle and the similarity of nuclei and stars",
Journal of Fusion Energy 25, 107-114 (2006)
arxiv.org/pdf/nucl-th/0511051v1
With kind regards,
Oliver K. Manuel
Dec 30, 2010
Rank: 3 / 5 (2)
Wow, sounds plausible to me. Would it be easy to devise an experiment to test if the presence of EM radiation stretches space? My guess is that, if true, this mechanism requires grand scales to operate on. Therefore any verification by experimentation would be difficult.
Dec 30, 2010
Rank: 3.7 / 5 (3)
Ethelred,
I don't think so. I think that the result is a less energetic light over a longer duration, so same energy.
fyi, I am sure we'll give you most favored crank status is you insist though. Say something about wave particle duality and the impossibility of my suggestion...
Dec 30, 2010
Rank: 4.2 / 5 (5)
Of course not QC, you're the onnnllyyyyyy one on the planet who actually has thought it all through. Ever hear the one about the black sheep of the family? If you can't think of who it is in your family, you're it.
Similarly, if you think the only one out of everyone on the planet that has brains is you, and that nobody else has thought about something because you don't like that they don't agree with you, then you are the intellectual black sheep. Perhaps you might sit down and re-evaluate your own conclusions instead of assuming that nobody else has thought of the better answer.
Dec 30, 2010
Rank: 4.3 / 5 (6)
See, there you go again Quantum. You really need to sit back once and consider that the reason you keep getting low feedback is that you keep pumping out crap for opinions most of the time.
Simple as that.
Dec 30, 2010
Rank: 4 / 5 (4)
Quantum, remember this next time you travel cross country using GPS. The satellites seem to think it works.
Dec 30, 2010
Rank: 3 / 5 (2)
Thanks Shootist. When I said I thought it was curious, it was a "wow that's weird" statement, not a "I'm QC and I know better than the scientists who make their living at this" statement.
Thanks for the clarification.
Dec 30, 2010
Rank: 4.3 / 5 (4)
Beelize posted an article in an effort to refute Inflation, and I pointed out that the article failed to do so. All that article meant was our understanding of galaxy formation is far from complete, but it nowhere conflicted with our present understanding of the Inflationary period.
Reading comprehension: go develop some.
Dec 30, 2010
Rank: not rated yet
Of course, we will never prove it.
Dec 30, 2010
Rank: 5 / 5 (3)
Write up a mathematical model for your theory; tell us all why this is better than existing explanations of cosmology; get your theory to predict something more convincing than the CMB and abundance of elements in the universe before observation; then you'd be on to something.
Dec 30, 2010
Rank: 5 / 5 (4)
Since radiant flux drops off as a square of distance from the emitter, then if photons caused expansion of space, the expansion would be quadratically exaggerated around the most luminous loci -- such as stars, globular clusters, and galaxies, etc.
As far as I know, the observational data indicates that expansion is in fact uniform everywhere: just as much at the centers of density nodes and sheathes of the cosmic web, as in the great voids between.
Also in GR, energy bends space just as much as matter does, and in the same way too. Both a high concentration of photons, and a high equivalent concentration of nucleons, should result in a geometrically equivalent gravitational well.
Dec 31, 2010
Rank: 3 / 5 (1)
i thought the reason for the energy density theories was that spacetime is not expanding uniformly everywhere, and seems to favor the voids between galaxy clusters
Dec 31, 2010
Rank: 5 / 5 (2)
Think of it this way. When you boil water the temperature at the surface of the water increases steadily but you don't get a good rolling boil until the energy of the surface molecules is greater than the coefficient of adhesion between surface molecules.
Apply this to matter in in the Universe. On large scales, gravity is inversely proportional to distance. Repulsion under dark energy is porportional. So on large scales, like interfilament space the rate of expansion is the same as the rate of expansion within intrafiliment space. But within intrafiliment space there are other force vectors like gravity, EM, etc that mutually attract and draw matter through space.
Dec 31, 2010
Rank: 5 / 5 (4)
Now the really great thing about this theory is it explains why some of our calculations for charge carrier attributes and force of attraction are off by a small but non-zero amount. More data from particle accelerators is allowing us to hone in on what the exact metric of expansion is by virtue of this discrepancy.
Dec 31, 2010
Rank: 4 / 5 (1)
It can't be a decrease in the energy of the light. The reason for this is red shift wouldn't exist.
As a photon of light travels through space and space stretches, the wavelength of the photon-wave is streched as well which is what provides the shift to the red. Now we're fairly sure that quanta of energy are of fixed sizes, due to observation. Every photon has the same amount of juice to it, it simply occupies a longer or shorter wavelength, which constantly increases w/ space.
Dec 31, 2010
Rank: 4 / 5 (1)
Probably the best analogy I can give is this. Let's say it takes 50 units of energy to run 50 yards. If I was to make you run 60 yards, logically you'd say it takes 60 units of energy to cover the increased distance, and you'd be correct.
But what if I made the field longer, without making the field longer? That's the expansion of space. Space never changes in size, only in volume. Sounds messy I know, but here's the wash.
Let's say I take the 50 yard run and stretch it like a rubber band to an equivalent of 60 yards, but I also stretch the runner by the same amount. The runner will only use 50 units of energy to cover that distance even though it has been streched because he has been streched as well.
Dec 31, 2010
Rank: 4.6 / 5 (5)
Thus, Ethelred is correct in surmising that the redshift saps energy from photons. Where that energy goes, is anyone's guess at this point as far as I'm aware.
I will note, however, that the same expansion of space also tends to increase the gravitational potential energy of co-orbiting bodies (by increasing the distance between them) -- thereby also adding energy into the overall system.
In fact, AFAIK much more energy is added into the system that way, than removed via photon red-shifting.
That's a major motivating factor for the "dark energy" postulate: where an unseen (extra-spatial?) energy reservoir (that doesn't itself curve space?) is being converted into the expansion of space -- and yet the OVERALL energy budget is kept balanced.
Dec 31, 2010
Rank: 1 / 5 (2)
http://
db.tt/
iVUcMRp
Dec 31, 2010
Rank: not rated yet
Scientifically you're correct. I recant.
Jan 01, 2011
Rank: 4 / 5 (4)
There is absolutely NO evidence that bound neutrons decay. NONE. I double checked this week. Now how about YOU go check the papers on the stacks of iron. That TWO stacks not just the one in India that I already asked you to check. Run the numbers lack I asked to do long ago. Its not that hard for guy with a Phd to do that.
You already know how much matter is converted to energy in the Sun. You know the mass of the Sun. Run the bloody numbers to figure out how neutrons MUST decay each second to get those results. Then figure out how many should have decayed in the stacks. Compare it to the number ZERO.
Do the bloody work and quit whinging about an alleged conspiracy.
Ethelred
Jan 01, 2011
Rank: 3 / 5 (2)
PinkElephantI was mostly thinking about the Background Radiation when I thought of this.
Skeptic_HereticNow that one I disagree with.Yes. Zero is what it is supposed to be. No rest mass therefor no energy. Pretty sure about that. So lower frequency IS lower energy. However as Pyle pointed out that should be due to the light being spread over space-time so the energy at any one instant or Plank Interval should be lower. That seems to be where I went wrong.
Well it seemed clever at the time.
Ethelred
Jan 01, 2011
Rank: 3.7 / 5 (3)
Actually I think you had it in your first post. It goes to the TIME part of space-time. It is spread out in time. I think, maybe. It does have to go somewhere. Should be possible to run the numbers IF someone actually knows enough math. Energy over time-space equivalents.
Now that is interesting. If true.
Well that is clever.
Thanks guys.
One more idea of mine mostly pissed away. Which is appropriate since I think that is when I came up with it.
Standing at the toilet.
Really.
Ethelred
Jan 01, 2011
Rank: 3 / 5 (2)
Except that particular god probably doesn't exist. And that image is way too large for the quality of the scan. Try using text next time.
You should keep this in mind.
If the theory doesn't fit the evidence then it is wrong.
Especially if the new evidence doesn't fit either as sometimes the early evidence is wrong. See Murry Gell-mann's work on the Weak force in 1957. SEVEN experiments, already done when they came up with it, showed it was wrong. Then new experiments showed those older experiment wrong.
http://www.
ted.com/talks/murray_gell_mann_on_beauty_and_truth_in_physics.html
So sometimes its important to be stubborn. But don't get carried away like you have since those iron stacks don't agree with you either and you are refusing to even check.
THAT is the sign of a Crank.
Ethelred
Jan 04, 2011
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