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wiggy
2011-Apr-25, 05:25 AM
OK, I know under all current models, the universe is expanding at an accelerating rate.

But in the back of my mind sits a doubt.

Here is the cause of my doubt.

How we measure time is with the period of a cesium atom.

Standard candles, doppler shifts all come down to frequency of atoms.

What if as the universe has expanded LINEARLY the frequency of elements has changed linearly with it. This would mean the benchmark for what me measure time with has changed linearly.

Apply this change in frequency to simple Newtonian physics. If the measure of time changes, velocity and acceleration change to. We would go from a linearly expanding universe to an exponentially expanding universe.

Just thought I'd throw this one out there because it's been bugging me for about 20 years now.

How can we prove that the rate of change of how we measure time is constant? If it has changed, the observations that tell us that the further reaches of the universe are accelerating away from us would be wrong.

So an alternative to some unknown force accelerating the universe apart could be ..... our measurements are wrong because the rate of change that we use to bench mark time has changed.

Has this idea ever been investigated before?

tommac
2011-Apr-25, 08:00 PM
If what you propose was true ... then what would be our basis of time? What we see here is the redshift. The further out in the universe you look the more it is redshifted. How would the frequency of atoms make everything in every direction become more redshifted?

what would cause the frequency of all atoms to change consistently over times in the past? How about here on earth? Would it have changed enough for us to detect it?


OK, I know under all current models, the universe is expanding at an accelerating rate.

But in the back of my mind sits a doubt.

Here is the cause of my doubt.

How we measure time is with the period of a cesium atom.

Standard candles, doppler shifts all come down to frequency of atoms.

What if as the universe has expanded LINEARLY the frequency of elements has changed linearly with it. This would mean the benchmark for what me measure time with has changed linearly.

Apply this change in frequency to simple Newtonian physics. If the measure of time changes, velocity and acceleration change to. We would go from a linearly expanding universe to an exponentially expanding universe.

Just thought I'd throw this one out there because it's been bugging me for about 20 years now.

How can we prove that the rate of change of how we measure time is constant? If it has changed, the observations that tell us that the further reaches of the universe are accelerating away from us would be wrong.

So an alternative to some unknown force accelerating the universe apart could be ..... our measurements are wrong because the rate of change that we use to bench mark time has changed.

Has this idea ever been investigated before?

PetersCreek
2011-Apr-25, 08:31 PM
If what you propose was true ...

As you know well, this is the Q&A forum and not the place to explore a 'proposal'.

wiggy,

If you're looking for mainstream answers to your questions, you're in the right place. However, if you're actually advocating an idea that runs counter to mainstream understanding, you should post it in the Against The Mainstream forum...but only if you're fully prepared to defend it according to our rules. If you haven't already done so, please read those rules, linked in my signature line below.

astromark
2011-Apr-25, 09:01 PM
By careful examination. By relentless study of known facts. By modeling of all contingencies...

The whole point of science is just that. We modify the science as the information becomes clearer.

We form a mainstream view that is science based. Not ' I have a suspicion, a feeling, a thought.'

You might have a nagging doubt. Thats yours. You can seek to find answers and many have...

Science is never set in concrete and will change as information is attained...

Looking across this subject as we have many times. No such change of view is apparent.

Tensor
2011-Apr-25, 09:11 PM
OK, I know under all current models, the universe is expanding at an accelerating rate.

How we measure time is with the period of a cesium atom.

What if as the universe has expanded LINEARLY the frequency of elements has changed linearly with it. This would mean the benchmark for what me measure time with has changed linearly.

Apply this change in frequency to simple Newtonian physics. If the measure of time changes, velocity and acceleration change to. We would go from a linearly expanding universe to an exponentially expanding universe.


Has this idea ever been investigated before?


About 2 billion years ago, there was a natural nuclear reactor operating at Oklo (http://www.physics.isu.edu/radinf/Files/Okloreactor.pdf). The nature and amount of the daughter nuclides of that reactor match what we currently see in nuclear reactors. If time was accelerating as you suppose, the fine-structure constant (http://scienceworld.wolfram.com/physics/FineStructureConstant.html), which uses c in its equations, would not allow the reactions of Oklo to proceed the same as current reactions. As a result, the idea that time is changing (or to be more precise, has changed since the operation of Oklo) is not supportable.

There is a small chance that it could be changing, but the measurement of Samarium isotopes has to have the ratio of proton to electron mass change at the exact same ratio as the fine structure constant. There has been some research that indicates that the fine structure constant has changed, but there has not been any verification of such results.

Also, you can't use Newtonian physics as an example. Newtonian physics does not include Relativity or Quantum phenomena. Which are required to explain current observations.

wiggy
2011-Apr-25, 09:49 PM
no, looking for a mainstream answer.
How do we know our benchmark of time is correct and that it has not changed over billions of years.
Just listened to the astronomy cast (how we know what we know) episode about standard candles, etc.
No mention of standard time, just wondering what backs it all up.

Tensor below is heading in the right direction :)

wiggy
2011-Apr-25, 10:06 PM
@Tensor

Thanks for filling in the "how we know what we know"bit. :)

I understand (not arguing, just informing you of my base knowledge) the Newtonian physics vs relativity factor. But if the "standard candle" of time was changing, it would effect even the simplest of calculations.

So the totally non ATM question of "how we know what we know" is, how do we know that the frequency of atoms, light, etc is constant and has not changed as space expanded. Is there a proof, or is it assumed?

AndrewJ
2011-Apr-26, 12:45 AM
How we measure time is with the period of a cesium atom.


We measure time in seconds each of which is 1/60th of 1/60th of 1/24th of a rotation of the Earth. I think the comparison with cesium is due to its period being highly regular whereas the rotation of the Earth can be affected by tidal forces.

wiggy
2011-Apr-26, 03:16 AM
There isn't a 60/60/24 gear train bolted to one of the poles. The SI unit of a second is based on the period of a cesium atom. Is there any way of knowing if that Period has been constant as the the universe has changed in density?

Tensor
2011-Apr-26, 03:33 AM
@Tensor

Thanks for filling in the "how we know what we know"bit. :)

I understand (not arguing, just informing you of my base knowledge) the Newtonian physics vs relativity factor. But if the "standard candle" of time was changing, it would effect even the simplest of calculations.

So the totally non ATM question of "how we know what we know" is, how do we know that the frequency of atoms, light, etc is constant and has not changed as space expanded. Is there a proof, or is it assumed?

Again, the reactor at Oklo has the same daughter nuclides, in the same proportions, that current reactors have. Since the fine structure constant (FSC) is basic to nuclear reactions, any change in the FSC, will affect reactions. Since the reactions at Oklo have the same results as current reactors, that indicates that the FSC has not changed in the last 2 Billion years of expansion (and in the case of the last 2 Billion Years, expansion has accelerated). That is a flat out observation. The simplest explanation is that the FSC hasn't changed.

Why is that the simplest? Well, if you follow the link I gave above, you will find that one of the constants in the FSC is c. The units in c are some sort of distance per second. If the rate of time passage was changing, then c would be changing (since the value of c is partially based on time), and as a resuilt, the FSC would be changing. With that, you would get different reactions at Oklo, compared to reactions today, with a difference in the daughter nuclides. Since they are not different, then c has not changed. The other explantion is that one (or more) of the other constants in the FSC equation is also changing. But, changing just at the right amount to offset the change in c. Occam's razor suggests that c is not changing.


However, if you need more examples, then there is this: the calculations used for Big Bang nucleosynthesis (BBN) ( http://astro.berkeley.edu/~mwhite/darkmatter/bbndetails.html) would also be affected by the FSC. If the FSC was different than it is today, then the creation of deuteriun, Helium 3, Helium 4, and Lithium 7 would be different from the amount observed vs the amount calculated for the BBN. While the amount for Lithium is off, it can be accomodated within the models, outside of a changing FSC. The amounts for Helium 3 and Helium 4 are quite good and would not match as well if the FSC had changed.

There is also the constraints placed on the FSC, based on the CMB. here (http://arxiv.org/pdf/0909.3584v1) is a paper explaining that the the FSC then and the FSC now is identical, within experimental limits.

Feel free to point out in any of those links where you think the papers or explanations are wrong.

wiggy
2011-Apr-26, 06:48 AM
thanks :)

Not the sort of stuff covered in every day classes.

Question not answered, but from what I am reading, its a question still being asked. Are our constants, constant?

tommac
2011-Apr-26, 01:15 PM
The standard candle is just an distant event with known color output. We can determine how fast they are receeding by the amount of redshift.

Are you asking how confident we are that these standard candles output the same color throughout time?

I guess I am missing the connection between time slowing down ( in your OP ) and the universe expanding.


@Tensor

Thanks for filling in the "how we know what we know"bit. :)

I understand (not arguing, just informing you of my base knowledge) the Newtonian physics vs relativity factor. But if the "standard candle" of time was changing, it would effect even the simplest of calculations.

So the totally non ATM question of "how we know what we know" is, how do we know that the frequency of atoms, light, etc is constant and has not changed as space expanded. Is there a proof, or is it assumed?

tommac
2011-Apr-26, 01:19 PM
@Tensor
Per this post ... I also read somewhere that there is actually a very delicat balance where if these constants changed matter as we know it would be signifigantly different due to the shape of the elementary particles or something. Is that true?


Again, the reactor at Oklo has the same daughter nuclides, in the same proportions, that current reactors have. Since the fine structure constant (FSC) is basic to nuclear reactions, any change in the FSC, will affect reactions. Since the reactions at Oklo have the same results as current reactors, that indicates that the FSC has not changed in the last 2 Billion years of expansion (and in the case of the last 2 Billion Years, expansion has accelerated). That is a flat out observation. The simplest explanation is that the FSC hasn't changed.

Why is that the simplest? Well, if you follow the link I gave above, you will find that one of the constants in the FSC is c. The units in c are some sort of distance per second. If the rate of time passage was changing, then c would be changing (since the value of c is partially based on time), and as a resuilt, the FSC would be changing. With that, you would get different reactions at Oklo, compared to reactions today, with a difference in the daughter nuclides. Since they are not different, then c has not changed. The other explantion is that one (or more) of the other constants in the FSC equation is also changing. But, changing just at the right amount to offset the change in c. Occam's razor suggests that c is not changing.


However, if you need more examples, then there is this: the calculations used for Big Bang nucleosynthesis (BBN) ( http://astro.berkeley.edu/~mwhite/darkmatter/bbndetails.html) would also be affected by the FSC. If the FSC was different than it is today, then the creation of deuteriun, Helium 3, Helium 4, and Lithium 7 would be different from the amount observed vs the amount calculated for the BBN. While the amount for Lithium is off, it can be accomodated within the models, outside of a changing FSC. The amounts for Helium 3 and Helium 4 are quite good and would not match as well if the FSC had changed.

There is also the constraints placed on the FSC, based on the CMB. here (http://arxiv.org/pdf/0909.3584v1) is a paper explaining that the the FSC then and the FSC now is identical, within experimental limits.

Feel free to point out in any of those links where you think the papers or explanations are wrong.

Tensor
2011-Apr-26, 02:27 PM
@Tensor
Per this post ... I also read somewhere that there is actually a very delicat balance where if these constants changed matter as we know it would be signifigantly different due to the shape of the elementary particles or something. Is that true?

Not so much as the shape, after all, our current models use point particles. Matter could be different in many ways, depending on exactly what constant, or constants change. For instance, if the strong force (I know, it's actually the color force but I'm simplifying here) was stronger, then fusion would be easier and fission more difficult(not saying fusion would be easier than fission). If the Electro-Weak force was stronger, then there is the possibility that there would be more weak interactions, making matter less stable. If gravity was as strong as the EM force, electrons would have to orbit further from the nucleous. Etc, Etc, Etc.

Tensor
2011-Apr-26, 02:35 PM
thanks :)

Not the sort of stuff covered in every day classes.

Question not answered, but from what I am reading, its a question still being asked. Are our constants, constant?

Through observation, our constants haven't changed since the last scattering, 13.4 Billion years ago. We have even tighter constraints on the change of the constants in the last two billion years, due to Oklo. There are currently no observations or theories that refute non-changing constants(at least none that are compatible with all observations).

I noticed that you didn't chose to point out anywhere in the papers I linked to, where the observations or explanations were wrong. Those papers and explanations show that the constants haven't changed. The answer to your question "Are our constants, constant?" is Yes. Unless, again, you care to point out where the papers are wrong.

Strange
2011-Apr-26, 02:42 PM
I'm fairly sure someone (probably Ken G) has said that it is all a matter of how you choose your coordinates. You could choose coordinates that make it appear that time ran slower in the past and space is not expanding - but this is just a different interpretation of the same underlying theory (GR). But the most natural coordinatization results in the interpretation that space is expanding.

wiggy
2011-Apr-27, 01:52 AM
I noticed that you didn't chose to point out anywhere in the papers I linked to, where the observations or explanations were wrong. Those papers and explanations show that the constants haven't changed. The answer to your question "Are our constants, constant?" is Yes. Unless, again, you care to point out where the papers are wrong.

No nothing wrong.

I just can't get my head around the whole accelerating universe. I learn best by asking weird questions.

Not arguing - learning :)

WayneFrancis
2011-Apr-27, 01:57 AM
No nothing wrong.

I just can't get my head around the whole accelerating universe. I learn best by asking weird questions.

Not arguing - learning :)

Don't feel bad we are all in the same boat. Our brains didn't evolve to intuitively grasp these concepts because well we don't really experience them. It amazes me we can even contemplate the concepts at all :)

tommac
2011-Apr-27, 07:57 PM
One more thing regarding this but I still am stretching to remember ... but is there a case that under super strong magnetic forces ( like near a magnatar ) the orbits of some atoms become warped or something? Sorry if this is off topic ( feel free to split the thread if needed )

I found this:


As described in the February 2003 Scientific American cover story, remarkable things happen within a magnetic field of magnetar strength:

In a field of about 10 5 teslas atomic orbitals deform into cigar shapes. At 10 10 teslas, a hydrogen atom becomes a spindle 200 times narrower than its normal diameter.




Not so much as the shape, after all, our current models use point particles. Matter could be different in many ways, depending on exactly what constant, or constants change. For instance, if the strong force (I know, it's actually the color force but I'm simplifying here) was stronger, then fusion would be easier and fission more difficult(not saying fusion would be easier than fission). If the Electro-Weak force was stronger, then there is the possibility that there would be more weak interactions, making matter less stable. If gravity was as strong as the EM force, electrons would have to orbit further from the nucleous. Etc, Etc, Etc.

Tensor
2011-Apr-27, 08:20 PM
One more thing regarding this but I still am stretching to remember ... but is there a case that under super strong magnetic forces ( like near a magnatar ) the orbits of some atoms become warped or something? Sorry if this is off topic ( feel free to split the thread if needed )

I found this:

As described in the February 2003 Scientific American cover story, remarkable things happen within a magnetic field of magnetar strength:

In a field of about 10 5 teslas atomic orbitals deform into cigar shapes. At 10 10 teslas, a hydrogen atom becomes a spindle 200 times narrower than its normal diameter.



You asked about basic constants and elementary particles. Using magnets and magnetars may not be possible if the constants have changed. Also, atoms are not elementary particles. Electroms, Quarks, etc are elementary particles.

EigenState
2011-Apr-27, 08:40 PM
Greetings,


One more thing regarding this but I still am stretching to remember ... but is there a case that under super strong magnetic forces ( like near a magnatar ) the orbits of some atoms become warped or something?

Sounds like the Paschen-Back effect. LS coupling totally breaks down such that only mL and mS are good quantum numbers.

Best regards,
EigenState

WayneFrancis
2011-Apr-28, 12:48 AM
One more thing regarding this but I still am stretching to remember ... but is there a case that under super strong magnetic forces ( like near a magnatar ) the orbits of some atoms become warped or something? Sorry if this is off topic ( feel free to split the thread if needed )

I found this:

? I'm trying to figure out how this has to do with the original post? Sure an atom might "deform" under a strong electromagnetic field but so what? Remove that field and it will snap back to its normal shape.