Quasars: Mileposts marking the universe's expansion

Sep 18, 2012

Scientists can't travel deep space the way Columbus sailed and charted the New World or Lewis and Clark mapped the west. But, researchers at Case Western Reserve University and two partnering institutions have found a possible way to map the spread and structure of the universe, guided by the light of quasars.

The technique, combined with the expected discovery of millions more far-away over the next decade, could yield an unprecedented look back to a time shortly after the Big Bang, when the was a fraction the size it is today.

Researchers found the key while analyzing the visible light from a small group of quasars.

Patterns of light variation over time were consistent from one quasar to another when corrected for the quasar's redshift. This redshift occurs because an expanding universe carries the quasars away from us, thus making the light from them appear redder (hence the term), and also making the time variations appear to occur more slowly.

Turning this around, by measuring the rate at which a quasar's light appears to vary and comparing this rate to the standard rate at which quasars sampled actually vary, the researchers were able to infer the redshift of the quasar.

Knowing the quasar redshift enables the scientists to calculate the relative size of the universe when the light was emitted, compared to today.

"It appears we may have a useful tool for mapping out the expansion history of the universe," said Glenn Starkman, a physics professor at Case Western Reserve and an author of the study, published this summer in .

"If we could measure the redshifts of millions of quasars, we could use them to map the structures in the universe out to a large redshift."

The larger the redshift, the farther and older the .

The group plans to seek larger samples of quasars, to confirm the patterns are consistent and can be used to calculate their redshifts everywhere across the universe.

The work was led by De-Chang Dai, who earned his PhD working with Starkman and was most recently a member of the Astrophysics, Cosmology and Gravity Centre, University of Cape Town. The other authors include Amanda Weltman, PhD, a senior cosmology lecturer at the Centre, and brothers Branislav Stojkovic, a doctoral student in computer science and engineering, and Dejan Stojkovic, a physics professor at the State University of New York at Buffalo. Dejan Stojkovic also earned his PhD with Starkman and was later a visiting assistant professor at Case Western Reserve.

The scientists graphed the amount of light from 14 quasars recorded by the Massive Compact Halo Objects project, which sought evidence of dark matter in and around the Milky Way. Light from each quasar was measured repeatedly over hundreds of days.

Graphing revealed phases during which the amount of light would either increase or decrease in a linear fashion over an extended period of time.

Although other properties varied, the rate at which the measurable light changed was nearly identical among all 14 quasars, once scientists corrected for the effects of the universe's expansion.

"It's as if there was a dimmer switch on them with someone turning it to the left then the right," Starkman said. "The overall trend was surprisingly consistent."

This consistency of patterns enabled the scientists to accurately calculate the cosmological redshift of one quasar from another.

The researchers tested this capability in two ways.

They fit segments of the light curves, that is, the measured light over time, to straight lines. The slopes of the lines were consistent and appeared to be directly related to the quasars' redshifts.

By comparing corresponding slopes of 13 quasars with a known redshift value to the slopes of one other quasar, the researchers could calculate the redshift of the lone quasar within two percentage points.

In a second approach, the researchers took large sections of the light curves of two quasars and concentrated on the segments that matched most closely. By varying the ratio of the redshifts of the two quasars to try to get the best possible match of the two light curves, they were able to determine the ratio of the quasars' redshifts to within 1.5 percentage points.

Astronomers have used the bright light of supernovae with redshifts up to about 1.7 to measure the accelerating expansion of the universe. A star with a redshift of 1.7 would have been emitting that light when the universe was 2.7 times smaller than today.

Quasars are older and farther away and have been measured with redshifts of up to 7.1, which means they emitted the we are seeing when the universe was as small as one-eighth the size it is today.

If this method of determining quasar redshifts proves applicable to higher quasars, scientists could have millions of markers to trace the growth and evolution of structure and the expansion of the universe out to large distances and early times.

"This could help us learn about how gravity has assembled structure in the universe." Starkman said. "And, the rate of structure growth can help us determine whether dark energy or modified laws of gravity drive the accelerated expansion of the universe."

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Twin
1.6 / 5 (5) Sep 18, 2012
I'm not an astronomer, just an interested reader.
With this data, could we begin to estimate where ( or even which direction ) the universe began?
Is it possible that, rather than matter being pushed at an accelerating rate by dark energy, it may be drawn by the sheer void outside of matter? Might matter be falling into a void as in proximity to a black hole? Gravity seems, after all, to be an accelerating force.
antialias_physorg
4.4 / 5 (12) Sep 18, 2012
With this data, could we begin to estimate where ( or even which direction ) the universe began?

Since we're living ina n expanding (and not an exploding) universe the answer to 'where' is everywhere (no joke).
You and I and everyone else is standing exactly at the center of the universe. (Otherwise we would not be seeing the CMBR coming from all direction sbut just from one direction)

Might matter be falling into a void as in proximity to a black hole?

Again, this would mean that stuff would be moving at different speeds7accelerations when looking indifferent directions. But that is not observed. We observe that galaxies farther out are moving away from us faster (on average) than those closer by. This speaks of expansion and not of a force (which would act inversely to the radius squared from its center)

dtyarbrough
1 / 5 (10) Sep 18, 2012
Our solar system is becoming more opaque to light. All distant objects are becoming dimmer at a rate that will make our sun appear 1/2 km farther away in 100 years. The rate in the increase in opaqueness in increasing. There is no expansion. There was no big bang. Expansion, created for any reason, will have only one center but the illusion of an expansion can appear centered anywhere.
jamesbuddy
4.7 / 5 (12) Sep 18, 2012
Hey antialias I figured I'd show some appreciation. I've seen many posts from you helping people and explaining things without disrespect. You don't have to do it by any means and you still take the time. I'm probably speaking for plenty of others when I say good job. People need people like you even for small things so I respect what you do because there is no shortage of jerk offs. People like you make the comments worth reading because otherwise it would just be childish arguments and of course crackpots.
dtyarbrough
1.2 / 5 (10) Sep 18, 2012
Red shift analysis of light assumes you know where the light was when the absorbtion lines occured. Emission lines would be a more accurate measurement. Reddening of the light is due to the fact that all visible wavelengths scatter more that red light. This is proportional to distance, not speed. If the universe expanded 2.7 times while the light traveled, ultraviolet would become infrared by the time it reached us. The absorbtion lines would no longer be within the visible spectrum. The light we see is what's left of the original light, not a wavelength shifted example of that light.
Fleetfoot
5 / 5 (9) Sep 18, 2012
Red shift analysis of light assumes you know where the light was when the absorbtion lines occured. Emission lines would be a more accurate measurement.


Reliable redshift figures are almost always based on spectral lines, emission where available or absoption where, as you say, we can be sure it occurs close to the source.

Reddening of the light is due to the fact that all visible wavelengths scatter more that red light.


Right, it's a problem in many areas of study but doesn't move the spectral lines so isn't significant in measuring redshift.

If the universe expanded 2.7 times while the light traveled, ultraviolet would become infrared by the time it reached us. The absorbtion lines would no longer be within the visible spectrum.


Correct, that is precisely the cause of the Lyman Alpha forest and the Gunn-Peterson trough.
antialias_physorg
4.9 / 5 (7) Sep 18, 2012
You don't have to do it by any means and you still take the time.

Not out of the goodness of my sould. I often am bored at work (these slow compile times are killing me).

But thanks for your the props. Feels good to be appreciated.
dtyarbrough
1.3 / 5 (6) Sep 18, 2012
"Correct, that is precisely the cause of the Lyman Alpha forest and the Gunn-Peterson trough."
My point was that if starlight typically peaks in a particular wavelength, the farther away it is, the peak would be in a longer wavelength when it reached us. I don't believe this is observed. Where are the green stars?
TopherTO
5 / 5 (5) Sep 18, 2012
Hey antialias I figured I'd show some appreciation. I've seen many posts from you helping people and explaining things without disrespect.


Agreed! I find astronomy/physics fascinating mind-food to distract me from slow work days in the cubicle farm. Quarks, anti matter, dark energy. Some seriously heady shiz for a history grad like myself. But I'm okay with reading things that are mostly beyond my comprehension. That said, I agree I seem to gravitate toward AntiAlias' comments, which I can digest without feeling I am blindly buying into some tin foil hat theory.

So big up yourself AntiAlias, maybe you have a following of layman astronomers? You are Twitter?? (jk)
Fleetfoot
5 / 5 (5) Sep 18, 2012
My point was that if starlight typically peaks in a particular wavelength, the farther away it is, the peak would be in a longer wavelength when it reached us. I don't believe this is observed.


This is a galaxy in the Hubble UDF:

http://www.nasa.g...axy.html

"The tiny, dim object is a compact galaxy of blue stars .." "The proto-galaxy is only visible at the farthest infrared wavelengths observable by Hubble."

Where are the green stars?


Stars are reasonably close to black body radiators (though not perfect by any means). This applet lets you see the colour for different temperatures:

http://www.astro....ody.html

Move the slider fully to the right, on the left you see a blue star. Move the slider to the left and the colour slowly changes to red but never goes through green. These charts show why:

http://en.wikiped...an_locus

Redshifting preserves that spectrum.
ValeriaT
1.7 / 5 (6) Sep 18, 2012
Quasars: Mileposts marking the universe's expansion
The problem is, just the red shift of quasars doesn't play well with hypothesis of Universe expansion.. http://phys.org/n...752.html
Fleetfoot
5 / 5 (5) Sep 18, 2012
The problem is, just the red shift of quasars doesn't play well with hypothesis of Universe expansion.. http://phys.org/n...752.html


Old news gets superseded. Hawkins' technique is OK in theory but needs many more decades of data before it can expose the other side of the peak. His mistake was thinking that absence of detection implied detection of absence.

The new method works :

http://arxiv.org/abs/1204.5191
yyz
4.3 / 5 (7) Sep 18, 2012
"Red shift analysis of light assumes you know where the light was when the absorbtion lines occured. Emission lines would be a more accurate measurement."

"...if starlight typically peaks in a particular wavelength, the farther away it is, the peak would be in a longer wavelength..."

This is why we see the Lyman-alpha *emission* line (rest wavelength=912A, in the UV) shifted to ~9230A (in the IR) in the high redshift Lyman Alpha Blob dubbed Himiko(z=6.95):

http://www.solsta...ko2s.jpg

http://www.solsta...miko.htm

This isn't the result of our solar system becoming "more opaque" to light.
Deathclock
3 / 5 (4) Sep 18, 2012
(these slow compile times are killing me).


You too? I write for a Texas Instruments TMS320F2812 using the cheapest JTAG debugger on the market and between compilation and flashing the processor with the new code I can read an article and comment on it too! In fact, it's the reason I post here so much...

The funny thing is, there exists a $5000 debugger that would cut my wait time down to 1/10th... If my employer actually did the math they would see it would pay for itself in increased productivity in a matter of months.

And yeah, as if your head wasn't big enough, you're pretty awesome, you are one of the few commentators who's posts I always read.
dtyarbrough
1 / 5 (7) Sep 18, 2012
"The tiny, dim object is a compact galaxy of blue stars .." "The proto-galaxy is only visible at the farthest infrared wavelengths observable by Hubble."
All visible wavelengths scatter more that red. (Far infrared scatters less). You can't see what doesn't reach the telescope. What is your point?
dtyarbrough
1 / 5 (6) Sep 18, 2012
"Stars are reasonably close to black body radiators (though not perfect by any means). This applet lets you see the colour for different temperatures:"
I did not mean the star would emit green light, but somewhere in an expanding universe there should be a blue star whose light has been shifted to the green part of the spectrum.

Fleetfoot
5 / 5 (5) Sep 18, 2012
"Stars are reasonably close to black body radiators (though not perfect by any means). This applet lets you see the colour for different temperatures:"

I did not mean the star would emit green light, but somewhere in an expanding universe there should be a blue star whose light has been shifted to the green part of the spectrum.


I understood what you meant but if you start with a blue star (at the left end of the locus) and then redshift it, you get a point somewhere farther right along the locus:

http://en.wikiped...an_locus

That locus doesn't pass through the green region of the chromaticity chart, that's why we don't see green stars due to redshifting.

We do however see galaxies of blue stars shifted to red and even infra-red. There is reddening due to dust etc. as well but the redshift is confirmed by spectral lines.
antialias_physorg
5 / 5 (4) Sep 18, 2012
I write for a Texas Instruments TMS320F2812 using the cheapest JTAG debugger on the market and between compilation and flashing the processor with the new code I can read an article and comment on it too!

For me the problem is mostly the huge code base we have to recompile (and also the fact that the data it runs on is large, heterogeneous, and the processing involved rather complex..so each run takes a good while)

I could do documentation work in the meantime...but you probably know how it is for someone writing code: documentation isn't really one of my favorite passtimes.

There is reddening due to dust etc. as well but the redshift is confirmed by spectral lines.

The thing for me was that while the lines shift they don't shift in relation to each other. And with each element/molecule having a very specific lineset the origin/distance at which the absorption takes place can be pinpointed rather accurately.

Fleetfoot
5 / 5 (4) Sep 18, 2012
There is reddening due to dust etc. as well but the redshift is confirmed by spectral lines.

The thing for me was that while the lines shift they don't shift in relation to each other. And with each element/molecule having a very specific lineset the origin/distance at which the absorption takes place can be pinpointed rather accurately.


I also find it interesting that the frequency of some lines depends on the value of the fine structure constant while others depend on its square, hence the ratio of two lines can tell you its value billions of years ago independent of the redshift.
Torbjorn_Larsson_OM
5 / 5 (5) Sep 18, 2012
@ dtvarbrough:

"Our solar system is becoming more opaque to light. All distant objects are becoming dimmer at a rate that will make our sun appear 1/2 km farther away in 100 years. The rate in the increase in opaqueness in increasing."

There is no such data though. Standard cosmology on the other hand, that incorporates a lot of observations, is well tested.

@ ValeriaT:

"just the red shift of quasars doesn't play well with hypothesis of Universe expansion".

The results here clearly shows that they do. The paper you pointed to was not on quasar red-shift but on their variation over time. And it is old, there has been a lot of progress on understanding quasars at high z since then.
yash17
1 / 5 (5) Sep 18, 2012
Yes, to get the real actual Universe structure, we must map the quasars' transit. I enthusiastically wait for fair observation to this. Anyway, if we get the observation that is unpleasing the Big Bang theory, please be free to open mind toward another more making sense theory, as theory is only a theory and nothing more than the theory itself, unless all observation data please that theory. Meanwhile we do know, there is another more making sense and friendly theory at current era.
Job001
1.3 / 5 (3) Sep 18, 2012
We observe that galaxies farther out are moving away from us faster (on average) than those closer by. This speaks of expansion and not of a force (which would act inversely to the radius squared from its center)
Do you know if an estimate of the emitted cumulative star light and relativistic particle mass from pulsars, quasars, etc. has been made? I assume that which is beyond us and moving away relativistically would have no gravitational component and is undetectable.
dtyarbrough
1 / 5 (5) Sep 19, 2012
"I understood what you meant but if you start with a blue star (at the left end of the locus) and then redshift it, you get a point somewhere farther right along the locus:"
That is physicist's attempt to explain the problem with black body radiation. When it comes to red shift, you can't just skip over frequencies or wavelengths. I don't even buy it when it comes to black body radiation.

yash17
1 / 5 (5) Sep 19, 2012
Celestial objects spreading away in mighty space, Yes!!! It is a fact! But the space (cosmos) expanding is just an interpretation and expectation. When the fair quasars and galaxies in mighty space mapping is done almost completely, the true truth about this will show up happily.
dtyarbrough
1 / 5 (5) Sep 19, 2012
If you look at the spectrum of our sun as seen from Hubble, and examine what red shift would do to the intensity of the visible portion of the spectrum, you would initially see the intensity increase and then fall off abruptly at greater distances. Brightness in the optical range would not be a true test of distance.
yash17
1 / 5 (5) Sep 19, 2012
We just have been too long trapped with current acceptable theory and have neglected other more logical theory possibility. Say, just possibility. We get too busy debating too many micro sciences (with their several controversies and arguments), while at the same time forgetting the macro one. Assuming we accept there is center of the Universe (certainly we can't detect yet), while dark matter is acting like Earth atmosphere in mighty space, then all mysteries about quasars and galaxies actions such as: disappearing quasar, no time dilation quasars, quasars as dying or death galaxies (not as babies of galaxies), quasars are everywhere in mighty space, celestial objects spreading away (not space expanding) can be viewed as not enigma anymore. And once more, if like water which can't be at temperature below zero degree Celsius (at atmospheric pressure), except changing structure to be ice, we can accept that condensed matter (compressed atom structure) like dark matter, black holes and q
yash17
1 / 5 (4) Sep 19, 2012
And once more, if like water which can't be at temperature below zero degree Celsius (at atmospheric pressure), except changing structure to be ice, we can accept that condensed matter (compressed atom structure) like dark matter, black holes and quasars can flit with the speed (z above 6) higher or much higher than the light speed (or at Einstein equation; E = mc2, the limiting factor is E not c), then we can also apprehend the entire Universe like we see our Earth planet; like Cloud and rain.
Fleetfoot
5 / 5 (3) Sep 19, 2012
"I understood what you meant but if you start with a blue star (at the left end of the locus) and then redshift it, you get a point somewhere farther right along the locus:"
That is physicist's attempt to explain the problem with black body radiation.


Thank you. As I said, stars are close to black body though not perfect. Here's a comparison for our Sun (yellow area vs. grey line):

http://zebu.uoreg...trum.png

When it comes to red shift, you can't just skip over frequencies or wavelengths.


Correct, take the intensity and wavelength and apply the shift to each component of the curve. Do that and it produces another blackbody at a different temperature. The applet shows the resulting colours:

http://www.astro....ody.html

I don't even buy it when it comes to black body radiation.


Tough, tell me what combination of stellar temperature and redshift you think would produce a green appearance.
Q-Star
3.3 / 5 (7) Sep 19, 2012
"Correct, that is precisely the cause of the Lyman Alpha forest and the Gunn-Peterson trough."
My point was that if starlight typically peaks in a particular wavelength, the farther away it is, the peak would be in a longer wavelength when it reached us. I don't believe this is observed. Where are the green stars?


Our sun is a predominately green star. If you would read just a little, you would know that.
Q-Star
3.3 / 5 (7) Sep 19, 2012
All visible wavelengths scatter more that red. (Far infrared scatters less). You can't see what doesn't reach the telescope. What is your point?


Depends on what is doing the scattering. Some wavelengths scatter more at times, and less at other times. It all depends on what it passes through.
Q-Star
3.3 / 5 (7) Sep 19, 2012
If you look at the spectrum of our sun as seen from Hubble, and examine what red shift would do to the intensity of the visible portion of the spectrum, you would initially see the intensity increase and then fall off abruptly at greater distances. Brightness in the optical range would not be a true test of distance.


Please promise you won't help your kids with their homework.

"spectrum of our sun" and "examine red shift" in the same sentence is about as foolish and as anything I've seen on this forum,,, it's up there with the pulsars and quasars are secret communications from from alien races.

Pssst, a hint to get you started. For light to "redshift" it requires a vast distance, and a considerable relative velocity. Our sun is a miniscule distance with with very little relative velocity,,, trying to look at the Sun's red shift would be trying to predict next week's weather by licking your finger and holding it in the air last week.
Fleetfoot
5 / 5 (1) Sep 19, 2012
examine what red shift would do ..


"spectrum of our sun" and "examine red shift" in the same sentence is about as foolish and as anything I've seen on this forum .. Pssst, a hint to get you started. For light to "redshift" it requires a vast distance ..


You missed the word "would". What he was suggesting was that you consider how our Sun would look from billions of light years away. His error was in not understanding the very limited range of colours that can be produced by applying cosmological redshift to a black body or similar spectrum.
ValeriaT
1.7 / 5 (6) Sep 19, 2012
The ripples at the water surface are scattered with Brownian noise in the similar way, like the light with quantum fluctuations of vacuum: their wavelength dilates during this. It can explain the red shift effect without requirements of the space-time expansion and Big Bang cosmology. The same effect leads into prediction of blue-shift for radiowaves, which is partially supported with INTEGRAL observations (positive violation of ISL), blue-shift of maser at Pioneer spaceprobes and with seeming shrinking of galaxies already.
We get too busy debating too many micro science, while at the same time forgetting the macro one
This is correct insight and it's the result of the overspecialization of contemporary physics (ant nest syndrome). IMO contemporary physicists are completely off the reality regarding these fundamental concepts. They cannot see or even admit the forest through the woods..
Q-Star
3.7 / 5 (6) Sep 19, 2012
You missed the word "would". What he was suggesting was that you consider how our Sun would look from billions of light years away. His error was in not understanding the very limited range of colours that can be produced by applying cosmological redshift to a black body or similar spectrum.


No he distinctly said as viewed from Hubble. That's not billions of light years, that is a tad over eight light minutes......

I quote: "If you look at the spectrum of our sun as seen from Hubble, and examine what red shift would do to the intensity of the visible portion of the spectrum,"
Fleetfoot
5 / 5 (3) Sep 19, 2012
No he distinctly said as viewed from Hubble. ..
I quote: "If you look at the spectrum of our sun as seen from Hubble, and examine what red shift would do to the intensity of the visible portion of the spectrum,"


It is ambiguously written, I thought the same at first but on a second look, I thought he meant the spectrum as seen from space rather than on Earth:

the spectrum of our sun as seen from Hubble


i.e. the difference between the yellow and red curves here:

http://zebu.uoreg...trum.png

He's wrong either way though.
ValeriaT
1 / 5 (6) Sep 19, 2012
the researchers took large sections of the light curves of two quasars and concentrated on the segments that matched most closely
This is what the data fishing is called....
yash17
1 / 5 (5) Sep 19, 2012
"It can explain the red shift effect without requirements of the space-time expansion and Big Bang cosmology"

Yes it is. With the assuming: existing of the Universe center (can't be detected yet), dark matter acting in mighty space like atmosphere at our planet, getting back to Newtonian (meaning gravity is the center of action in mighty Universe without help by space expanding), and with permission to Albert Einstein that we need the situation: if matter change structure becomes extremely solid (compressed atom structure), it can flit with speed far above the light speed (as long as energy needed to cause that action available), than many cases about quasars and celestial object spreading away turn to be not mysteries anymore.
We just need a little wise to glimpse that.
Fleetfoot
5 / 5 (3) Sep 20, 2012
the researchers took large sections of the light curves of two quasars and concentrated on the segments that matched most closely
This is what the http://en.wikiped...dredging is called....


No, that is called parameterisation, data fishing would be selecting only those slopes that matched the desired redshift.

The method is obviously in its infancy and could be used to refine values where an approximate redshift is available from photometric methods, but will eventually need to be shown to work on a new population without being customised for the specific sources before it is a usable tool for determining redshift without an a priori estimate.
Fleetfoot
5 / 5 (2) Sep 20, 2012
data fishing would be selecting only those slopes that matched the desired redshift
which is just the
the researchers .. concentrated on the segments that matched most closely


You are taking the quote out of context, that was when they were comparing two quasars without an a priori target. That is technically equivalent to finding the peak of the distribution curve for the ratio. However, they do have to be careful not to fall into the trap you outline with such techniques.

"Parametrisation" is ..


"Parametrisation" is defining a measurement method that extracts salient features without biasing the values.

new epicycles to Ptolemy model.


In a sense I agree, it is a purely empirical measurement at this stage. I don't think anyone has any firm ideas on the mechanism that creates these linear slope segments.

The fact that the slopes are time dilated shows that Hawkins' claim to the contrary was incorrect, he needed a longer timebase.
yash17
1 / 5 (4) Sep 21, 2012
"(these slow compile times are killing me)"

We do need that patience. This mighty space is too vast to map from here. Maybe, we will need numbers eras for that. It isn't like we at a century ago mapping New York City.

And now, I want a bet. If we could be more patient, slow but sure, all quasars, starting with the high one (z above 5 or 6 or 7) will get lost from our observation, whatever sophisticated the device or instrument we use. They might take time in months, years, centuries or many more to get vanished. No one of those quasars will become galaxies on our observation. Since today or maybe yesterday, even we can watch many galaxies will suffer dying becoming quasars. None of galaxies can deny that fate.

If that happens in contrary, you all win, I lose.
yash17
1 / 5 (3) Sep 21, 2012
"This speaks of expansion and not of a force (which would act inversely to the radius squared from its center)"

I only want a bet. Watched from here, many or most quasars having red shift above 6.5 (maybe above 6 or 5) won't get further to each other. Yes indeed. If we could observe them all more precise, even many or most of them getting closer to each other, while several still getting further away. Why? Of course, I know the answer.

If this isn't happened, simple!!! You win, I lose.

Send my best regards to: http://news.disco...ars.html
Fleetfoot
5 / 5 (1) Sep 22, 2012
.. If we could be more patient, slow but sure, all quasars, starting with the high one (z above 5 or 6 or 7) will get lost from our observation, whatever sophisticated the device or instrument we use. They might take time in months, years, centuries or many more to get vanished.


That is what the BB model predicts. Dark energy will push those distant objects over a "cosmic horizon" and they will vanish, but it will take billions of years.
Husky
not rated yet Sep 22, 2012
because there are no green stars, that is the reason I think green coloured plants/chlorophyl evolved. Chlorophyl absorpts mot energy in blu followed by red, hence it radiates back green
SteveL
not rated yet Sep 23, 2012
because there are no green stars, that is the reason I think green coloured plants/chlorophyl evolved. Chlorophyl absorpts mot energy in blu followed by red, hence it radiates back green
You are kidding, right?
yash17
1 / 5 (3) Sep 24, 2012
"That is what the BB model predicts. Dark energy will push those distant objects over a "cosmic horizon" and they will vanish, but it will take billions of years."

Thank you for responding me. I appreciate that.

Cart model expects: Dark matter is responsible to cause only living galaxies to spread away, not including quasars. By the ageing, galaxies get dying and death to become quasars which are extremely dense to cause the dark matter losing against gravity of "the center of the Universe" in pushing them.

So, quasars flit back toward center of the Universe, which is different direction against galaxies' course.

Then, at Hubble's law v = r Ho = cz, I expect Ho aren't the same for galaxies and quasars.

We expect, the work of mapping the quasars transit does observe whether many or most of the flitting quasars (having z above 6,5) still getting spreading away (getting further to each other) or the reverse, getting closer to each other. This is our contest.
Fleetfoot
5 / 5 (2) Sep 26, 2012
"That is what the BB model predicts. Dark energy will push those distant objects over a "cosmic horizon" and they will vanish, but it will take billions of years."

Thank you for responding me. I appreciate that.

Cart model expects: Dark matter is responsible to cause only living galaxies to spread away, not including quasars.


Recent observation have confirmed that quasars show time dilation which matches their redshift. Both observations prove quasars are moving away from us at the same rate as everything else.
SteveL
5 / 5 (1) Sep 26, 2012
Recent observation have confirmed that quasars show time dilation which matches their redshift. Both observations prove quasars are moving away from us at the same rate as everything else.
So, universal expansion is... universal.

Kind of makes me wonder - that space that is filling in the space as things spread apart, what is it?
yash17
1 / 5 (3) Sep 26, 2012
"Cart" model expects: Galaxies, by the work of dark matter, leave N spot (Universe nucleus; can't be detected yet) at space. Quasars (too dense to be drifted by dark matter) flit back toward N due to gravity of N and quasar. Quasars have opposite direction against galaxies' course. That's why quasars moving away from us faster than the speed of spreading away galaxies which have direction at relatively small different angle. It is quasars with high red shift will still get further against quasars with low red shift, moreover against galaxies including us. But there are conditions, for one example; the closest region to N, where quasars get closer to each other near them (says quasars all having red shift above 6.5 or more), before they vanish to mingle in the invisible Universe nucleus.
Fleetfoot
5 / 5 (2) Sep 27, 2012
"Cart" model expects: Galaxies, by the work of dark matter, leave N spot (Universe nucleus; can't be detected yet) at space. Quasars (too dense to be drifted by dark matter) flit back toward N due to gravity of N and quasar. Quasars have opposite direction against galaxies' course.


Quasars exist all over the sky. In you model those between us and 'N' would have high red shift but those on the opposite side of the sky would show a blue shift. That is not what is observed, your model is contrary to reality.
yash17
1 / 5 (4) Sep 27, 2012
"Quasars exist all over the sky."
Quasars as dying or death galaxies means they can exist everywhere they like.
"but those on the opposite side of the sky would show a blue shift."
Only elementary students buy this.

Or, maybe I should thanks God. None of quasars chasing Milky Way now.

Fleetfoot
5 / 5 (2) Sep 27, 2012
"but those on the opposite side of the sky would show a blue shift."
Only elementary students buy this.


That's what your description predicts, not even elementary students would "buy it".
yash17
2 / 5 (4) Sep 27, 2012
and how about this,

http://news.disco...ost.html

Just forget it???
Fleetfoot
5 / 5 (1) Sep 27, 2012
http://phys.org/news190027752.html#nRlvHow they could be used for measurement of Universe expansion, after then?


As I have explained at least twice before, Hawkins tried a method that simply didn't work due to the limited data he had. The new technique works because it uses much shorter spans.

Hawkins used a Fourier Transform which requires observations over a time span greater than the period of the peak frequency of the variations, the new technique only needs a few months of data.
Fleetfoot
5 / 5 (1) Sep 27, 2012
and how about this,

http://news.disco...ost.html

Just forget it???


Why, it is perfectly compatible with everything we know. Quasars shine while material is falling into them, if the supply runs out, they stop shining. The interesting point is that the brightness can reduce by a large factor quite quickly.

What has that got to do with your imaginary blueshift?
yash17
1 / 5 (3) Sep 27, 2012
Sorry. I should say,
This cosmos is three dimensions, not two. When we draw a straight line from N to Milky Way and then continue a head, we can depict certain small region after Milky Way around that line. If at that region there is quasar, we're dead. How big is that possibility? Ask the fate.
Quasars are free to exist or not to exist wherever they want. They are quite random filling the cosmos.
Fleetfoot
5 / 5 (1) Sep 28, 2012
Sorry. I should say,
This cosmos is three dimensions, not two. When we draw a straight line from N to Milky Way and then continue a head, we can depict certain small region after Milky Way around that line. If at that region there is quasar, we're dead.


As I said, we know of quasars all over the sky. The universe has no centre but if you choose some random point to call "N", there will be a quasar on the opposite side quite close to the line you describe. Like all the others, that quasar will have a high redshift so the distance between us and it is rapidly increasing. Why would you imagine it was a hazard?
antialias_physorg
5 / 5 (1) Sep 28, 2012
If at that region there is quasar, we're dead

Even for quasars the intensity of the emitted radiation drops off with the square of the distance from which they are observed. Beyond a certain distance quasars aren't dangerous.
yash17
1 / 5 (3) Sep 28, 2012
"The universe has no centre but if you choose some random point to call "N","

- N is certain, not random. We only can't detect yet (easier job rather than dreaming Big Bang)

"there will be a quasar on the opposite side quite close to the line you describe"

Really? If cosmos is two dimensions only, I buy that.
Fleetfoot
5 / 5 (1) Sep 28, 2012
there will be a quasar on the opposite side quite close to the line you describe


Really? If cosmos is two dimensions only, I buy that.


I mean in three dimensions. Think of a sphere with spots all over the surface. Pick a point outside the sphere and draw a line through the centre to the opposite side, then just pick the nearest spot. I don't understand why you think it needs to be 2D.
Fleetfoot
5 / 5 (3) Sep 28, 2012
The universe has no centre but if you choose some random point to call "N"
If the universe would have no center, then we couldn't expect the formation of matter (baryogenesis) just at the visibility boundary of it (a particle horizon).


It happened everywhere, otherwise the matter near us would not exist. We see galaxies at all distances from us to the limit of what we can observe.

In addition, the CMBR anisotropy may be interpreted as a vector heading to the center of alleged expansion, which is far outside the observable Universe scope.


No, that doesn't work, it only shows differential motion relative to the plasma that emitted the CMBR. If there were some very distant attractor, it would affect both the plasma and us so there would be no detectable dipole.
yash17
1 / 5 (3) Sep 30, 2012
Thank friend.
Now for a short, I buy your cosmos argument. It's maybe due to less data we get, or because I'm just not so sure yet with the answer in my head. Maybe later! Never mind for now. This point doesn't kill Cart model yet. This is only becoming mystery no 2 of Cart model (mystery no 1, the invisible Universe nucleus) comparing to a lot more enigma of BB model, such as: the BB event, the expanding space, the uncertainty of the end of cosmos.

And, what is "ULAS J1120+0641", quasar with z = 7.085 & 12.9 billion light years away from us, on BB model? Where the point is it come from? Toward where is its destination?

With Cart model, I am just waiting confirmation from further cosmological observation regarding that dead galaxy. It will get lost to sink in the invisible Universe nucleus.

Whatever way you try to explain it with BB model, either mathematically or physically, it will always launch & exhibit controversy.
Fleetfoot
5 / 5 (1) Oct 01, 2012
Thank friend.
Now for a short, I buy your cosmos argument. It's maybe due to less data we get,


This catalogue from 2010 lists over 133 thousand quasars:

http://www.aanda....-10.html

And, what is "ULAS J1120 0641", quasar with z = 7.085 & 12.9 billion light years away from us, on BB model? Where the point is it come from? Toward where is its destination?


In the BB model, it was created in that piece of space and is staying there, it is only the region between us and it that is expanding.

Whatever way you try to explain it with BB model, either mathematically or physically, it will always launch & exhibit controversy.


Scatter some dots on a piece of paper. Photocopy it with a magnification of 1%. If the first sheet is a map of galaxy clusters now, the copy is the same map a little under 200 milion years later. I don't think that is hard to understand.
yash17
1 / 5 (3) Oct 02, 2012
"I don't think that is hard to understand."

Right, even too easy to understand that.

But, I and many friends still grasp controversy about space expanding. It isn't work in my room, in front of my house, at solar system, at Milky Way, between Andromeda and Milky Way and nearing Quasars, while a friend of space, "time" works everywhere ignoring gravity.
Not to mention while the space as big as the Earth only, it had already expanded separating matter with ultra high gravity.

I buy the observation data you give, but it's just observation data.
Our friends at earlier time got observation data upon their capabilities, the Earth flat. Next, other friends got observation data all celestial objects circling the Earth.

Now, there must be a hint of current era.

Anyway thank you very much. We are at the same side. We both want a very true truth of this one Universe.
Fleetfoot
5 / 5 (2) Oct 02, 2012
It isn't work in my room, in front of my house, at solar system, at Milky Way, between Andromeda and Milky Way and nearing Quasars, while a friend of space, "time" works everywhere ignoring gravity.


It works everywhere but it is proportional to distance while local gravity is inverse square so dominates when objects are close, there is no mystery there.

Not to mention while the space as big as the Earth only, it had already expanded separating matter with ultra high gravity.


Since the universe was homogenous, every particle saw as much one one side as the other so no overall effect, that isn't a problem. It would be a problem for you though, how did matter first escape from "N"?

I buy the observation data you give, but it's just observation data.


All science starts with observation, it is our most reliable source.

Our friends at earlier time got observation data upon their capabilities, the Earth flat.


http://en.wikiped...Flat_Ear
yash17
1 / 5 (3) Oct 02, 2012
"What has that got to do with your imaginary blueshift?"

Sorry, have made you wait for 6 days.

We do this at sound, since couldn't at light (I just guess).
Draw 2 lines (30 km long each) making angle about 22 degrees at junction N. Mark point MW at 12 km from N on line 1. Mark point X at 12 km & point Q at 30 km from N on line 2.

This game is for the flight faster than sound speed only.

Order a supersonic flight SF to fleet from Q start at Mach 3.0 (accelerating or constant speed) straight toward N, while let MW just stay there.

We can do this in scale at lab or wherever. Even I do this at a piece of paper, cm scale.

Since SF at Q fleets until X on line 2, the two fellows get closer to each other.

What happen with my imaginary blueshift?

This is it. Friends at MW will start getting that redshift since SF leaves X. Even if SF stops before or at X, MW will still get redshit.

SF arrives earlier than sound.

Gracias amigo. Terima kasih
yash17
1 / 5 (3) Oct 02, 2012
Light wave will get same impact.

Cloud and rain theory (a Universe structure theory) state that dark matter (condensed atom structure matter, at extremely high temperature & pressure, fleeting with speed faster than light) acts like Earth atmosphere at cosmos. Universe nucleus (the vastest volume, the biggest mass, the highest temperature & pressure ever) launch its fog to cosmos. We can't see Universe nucleus due to that fog. In cosmos, that fog constructs galaxies. A huge amount of dark matter intrudes galaxies. At galaxies, at any random post, by pressure & temperature drop and other physical events, dark matter breaks becoming CMBR. By ageing, galaxies turn into quasars which are too dense for dark matter to continue to drag away. Quasars fleet back to Universe nucleus. Those all events happen in cycles continuously and eternally, unless at the unpredictable era ever, the One Mightiest, the Ruler and the Owner of the real one Universe, fates other rule.

Special thanks to PhysOrg
Fleetfoot
5 / 5 (1) Oct 03, 2012
We do this at sound, since couldn't at light (I just guess).


You can use particles faster than light but slower than c in a medium, look up "Cerenkov Radiation".

Draw 2 lines (30 km long each) making angle about 22 degrees at junction N. Mark point MW at 12 km from N on line 1. Mark point X at 12 km & point Q at 30 km from N on line 2.

Since SF at Q fleets until X on line 2, the two fellows get closer to each other.

What happen with my imaginary blueshift?

This is it. Friends at MW will start getting that redshift since SF leaves X. Even if SF stops before or at X, MW will still get redshift.


What you would see from SF is nothing from Q to a little before X, then a shock wave followed by a rapidly increasing redshift. On your graph paper, draw a line passing through MW and perpendicular to line MW-N. On the side of the sky containing N you would see redshifted aircraft. On the other side containing Q, you should see no sources but we see sources all over the sky.
yash17
1 / 5 (3) Oct 03, 2012
"On the other side containing Q, you should see no sources but we see sources all over the sky."

(Ha.....ha.....ha....., now you're kidding me, right?).

"Light wave will get same impact. "

You right. And sorry, there is mistake about that word.

So, for quasars, don't tell me you didn't know about this phenomenon yesterday. I wouldn't buy that. Even David Copperfield often plays this game.

Then, let it be your turn to answer that, as I am quite sure you knew that more detail than that.

You questioned me imaginary blueshift, and I've answered that. I thought it was enough for you.

So, you watch that hint earlier than me.

Terima kasih for all.
Fleetfoot
5 / 5 (1) Oct 04, 2012
"On the other side containing Q, you should see no sources but we see sources all over the sky."

(Ha.....ha.....ha....., now you're kidding me, right?).


No.

Think of the aircraft moving from Q towards N like a boat on water, it will produce a wake which is a narrow cone from the bow. The craft would first appear when that wake crosses the observer and it would seem to be in a direction perpendicular to the wake. Beyond that there should be no sources, and from first appearance to roughly your point X the shift should be blue.

In reality we see only redshifts and over the whole sky.

"Light wave will get same impact. "

You right. And sorry, there is mistake about that word.


Geometry doesn't allow speeds greater than light but I didn't bother with that as your model doesn't work anyway.

So, for quasars, don't tell me you didn't know about this phenomenon yesterday.


I still don't know what "phenomenon" you are describing, can you cite some published papers?
yash17
1 / 5 (3) Oct 05, 2012
Appreciate you paying attention a lot to my model, notwithstanding you not taking it.
This is cosmological observation Cart model expect.
We at MW will watch all quasars at all direction will redshift, in the condition:
1. All quasars between line MW-X and N (or above MW) will recede from us and they do redshift. Nevertheless, in actual way, they are getting closer one another.
2. All quasars between MW-X and Q (or below MW) will redshift. We will watch, they get away one another. But that isn't a real event.
3. In observation, all quasars at left side of MW will redshift and recede one another. But that isn't a real event.
4. In observation, all quasars at right side of MW will redshift and recede one another. But that isn't a real event.
5. At certain random time, we can observe there is a very unique event, a big explosion of quasar from nothing at all, followed by 2 quasars receding from one another.
If your cosmological observation isn't as 5 above, simple, just forget Cart model
yash17
1 / 5 (3) Oct 05, 2012
Part 2
Derivation.

Cart model grasps compressed atom structure matter (like dark matter, blackhole, quasar, which are all only existing at extremely high pressure & temperature) can fleet with speed faster or much faster than c, while standard atom structure can't.

Draw 2 lines (30 cm each) making angle about 22 degrees at junction N. Mark point MW at 12 cm from N on line 1, and Q at 30 cm from N on line 2. Mark a point X at line 2, at such a way, so MW – X perpendicular to line 2.

Assume a quasar fleeting (constant speed) start form Q with speed 3 times c toward N on line 2 and MW just stationary there.
yash17
1 / 5 (3) Oct 05, 2012
Part 3
Since quasar leaving Q and even pass N, we will see nothing at all. That quasar fleet 3 times of light. The light (the source) will arrive at MW in time we start watching that all, first, look like an explosion. After that, we will see 2 quasars getting away one another. (Remember when we see that, that quasar have already lost in N.)
First quasar will leave point X toward N, and a second one will fleet back from X toward Q. We will watch both quasars will redshift. The thing is, the one which we watch from X to N is a delaying watch of that quasar, while from X to Q is due to (in that special case) the light of that quasar which is fist arriving at MW is the light originated from the nearest point to MW (that is X), and the light which is last arriving at MW is the light originated from the farthest one (that is Q). This second appearing quasar is actually a reverse look of the real action of that quasar.

This phenomenon will never happen for object fleeting below light speed.
Fleetfoot
5 / 5 (1) Oct 06, 2012
That quasar fleet 3 times of light. The light (the source) will arrive at MW in time we start watching that all, first, look like an explosion. After that, we will see 2 quasars getting away one another. First quasar will leave point X toward N, and a second one will fleet back from X toward Q. We will watch both quasars will redshift.


This isn't to scale but should be adequate:

http://i47.tinypi...jgqq.png

The red lines are the shock wave produced shown when the object is at point "c" and they have just reached MW.

The blue line to "a" is perpendicular to the shock and shows where your explosion would be seen.

The green line is perpendicular to the line N-Q at point "b".

Between points a and b, the source is approaching and would show a blue shift which we never observe. The shift would go to zero at b then become a slight but increasing red shift.

This bears no resemblance to what is observed, we see high redshifts over the whole sky.
yash17
1 / 5 (3) Oct 07, 2012
"http://i47.tinypi...gqq.png"

In the case objects traveling much faster than light speed; a – b is too short to watch. a – b is the event when the explosion occurs from nothing at all; from no gas source. Just like magic. After that, we will see twin quasars separating one another. One quasar flits from a toward Q and another one from b toward N. Why quasar aQ also redshift? Because the wave which MW receives first coming from a with is the shortest wave length, and last coming from Q which is the longest wave length. That's why they redshift.

A lot of twin quasars in cosmos are in favour to explain the above event in cosmos. Why does twin quasar also like BB model?
Fleetfoot
5 / 5 (1) Oct 08, 2012
http://i47.tinypi...jgqq.png

In the case objects traveling much faster than light speed;


In reality objects cannot travel faster than 'c', they can only travel faster than the speed of light in a medium That margin is tiny for the IGM.

a – b is too short to watch. ... A lot of twin quasars in cosmos are in favour to explain the above event in cosmos.


That period would be visible for millions of years at your example figures, double quasars would just have separated by your model so should show a blue shift but many show high redshifts.

For relativistic velocities in your model, all quasars at low redshift should be in a thin band on the sky roughly perpendicular to the line to N. One direction (that towards N) should have the highest redshift. We don't see that at all, the redshift is uniform over the sky.

Why does twin quasar also like BB model?


Because they occur uniformly over the sky.
yash17
1 / 5 (3) Oct 08, 2012
Debate of space expanding & compressed atom structure matter traveling far above c will never end. Our next generation will judge that. Now, our honest is needed.

Our friends at earlier time watched the Earth flat.
Next, our friends watched the sun and entire celestial objects circling the Earth.
Current era, with extra sophisticated probes, we are watching the space expanding.

Now I leave it to you. I just give rough figure below. If your cosmological observation isn't like that, Cart model ends. I think that's a lot easier.

I won't bother you any longer. I have work to do. To me, cosmology is just for a fun.
yash17
1 / 5 (3) Oct 08, 2012
Draw 2 diagonal lines at such a way so, space A in reverse to B, and space C in reverse to D.

All quasars will redshift under condition:
1. All quasars at space A will recede from us and will redshift. But, they get closer one another. Those are a true event.
2. All quasars at space B, C & D will redshift & get away one another. But those aren't real event.
3. At any random time at space C & D, we will observe a very unique event, a big explosion occurs from nothing at all, followed by construction of 2 quasars which then receding from one another.
4. At any random time at space A, we will observe highest redshift quasars vanish.
5. At any random time at space B, we will observe highest redshift quasars construct galaxies. Actually this is a reverse & delaying look of that quasar and galaxy action at far earlier time.
Fleetfoot
5 / 5 (3) Oct 08, 2012
Our friends at earlier time watched the Earth flat.


No, that's a myth:

http://en.wikiped...at_Earth

I just give rough figure below. If your cosmological observation isn't like that, Cart model ends.


Observations are not like your model at all, redshifted quasars apear over the whole sky.

To me, cosmology is just for a fun.


Me too, but I prefer to build my understanding on what is actually observed rather than ignore reality in favour of a fantasy. Have fun with it though.
Fleetfoot
5 / 5 (1) Oct 08, 2012
Draw 2 diagonal lines at such a way so, space A in reverse to B, and space C in reverse to D.

All quasars will redshift under condition: ..


I don't follow your diagram this time but no matter, the one I drew before should make it clear that there would be little observed redshift or even blue shift for quasars seen at right angles to the line to "N". That is not seen so your model is simply wrong.
mikirdonk
1 / 5 (3) Oct 15, 2012
There is significant different between the 2 events; supersonic aircraft and quasars, that is the medium they travel. The aircraft traveling above sound speed breaks through the sound speed barriers, the air. The air is a medium interacting with sound wave. Since the source moves faster than sound waves it creates, it leads the advancing wavefront. This intense pressure wavefront will pass by a stationary observer before the sound it creates. That produces sonic boom and blueshift for a short until nearest point to MW.
At cosmos, quasars flitting above light speed breaks through the field of dark matter. The dark matter isn't a medium interacting with light wave. It won't influence the shift at all. We don't watch and feel direct effect which dark matter gets. Nonetheless, if we watch more detail, we will get a significant increasing of CMBR at Milky Way instead of sonic boom.
Fleetfoot
5 / 5 (1) Oct 16, 2012
There is significant different between the 2 events; supersonic aircraft and quasars, ...


Indeed, in reality, quasars aren't moving very fast at all and it is not possible for matter to travel faster than 'c'.

At cosmos, quasars flitting above light speed breaks through the field of dark matter. The dark matter isn't a medium interacting with light wave.


Right so we can ignore it. The intergalactic medium also includes hydrogen though and that does create a minute refractive index.

None of that matters, the point was that you haven't thought your argument out carefully enough. The model you described would create redshift only in one part of the sky with very little shift or even a blueshift at right angles to that. Reality is nothing like that.
mikirdonk
1 / 5 (3) Oct 16, 2012
Nature's facts are stronger than human theories.
Friends who think can easily see that.
Friends studying from their masters will follow the command.

Adios.
Fleetfoot
5 / 5 (2) Oct 18, 2012
Nature's facts are stronger than human theories.


Yes, and the fact is that quasars show the same range of redshift over the whole sky, it is not restricted to two opposite zones as your "theory" would produce.

Adios.


Adios friend, good luck correcting your model.

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