Article in this month's ASTRONOMY discussed experimental evidence (Airy disks seen around images of distant galaxies) indicating that time is not quantized at the Planck level.

This strikes me, if it holds up, as being extremely exciting. If time is not quantized, I can see no reason to expect space to be. And if the spacetime metric is not quantized, explaning the quantization of matter/energy in a continuum framework seems to indicate physics has more fun in store.

I'm massively ignorant in this area and would appreciate some knowledgeable input.

(Astronomy article.) I'd like to know more about it, myself. If it's true, seems like quantum theory has some explaining to do.

hmm... How much of a monkey wrench is this potentially for relativity? The basic math would seem to hold, but some of the constants that used to be givens would become variables if quantum theory is tripped up.

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The last time I felt a warm fuzzy feeling, I was informed by my doctor that it was just gas.

Really? I didn't think relativity gave a rat's patooty about quantum effects -- it could take 'em or leave 'em.

If time, by this new theory, is not something that can be assigned a quanitity, how does it fit mathematically within relativity? Would the means by which relativity determines the distortion of time need to change if time is not quantifiable? The equations I have seen for relativity in reference to time have time quantified as a unit subject to distortion, if time isn't something we can measure in units, would those equations still apply? Like I said, the math isn't in question, its the units it relies on. If the nature of the units changes or is rendered invalid, how would relativity now work?

Added: The article is saying that the unit known as a Planck time isn't real. This theory is attacking the way we define units of time basically by saying, time moves forward at a constant rate everywhere. It would seem to me this challenges the idea of distorting time via relativity by undermining relativity's abilty to use time as a constant. Not that time doesn't move forward, but its not meaurable the way relativity uses it. The danger I see is that this opens the door to variable lightspeeds, tired light and all that material that so many threads I read have trounced pretty thoroughly via relativity.

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The last time I felt a warm fuzzy feeling, I was informed by my doctor that it was just gas.

I didn't think time was really quantizied anyways. The Planck time is just the time it takes for light to travel a planck length.

Since the Planck length is the smallest meaningful measure of distance, that makes the Planck Time the smallest meaningful unit of time. But it doesn't mean that it was the smallest POSSIBLE unit.

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People who think they know everything are a great annoyance to those of us who do.

Well, yes and no (Man, talk about angels dancing on pinheads. Possibly my own).

My (admittedly outdated) training indicated that all measureable quantities have a limiting precision. (Not that time cannot be assigned a dimension, sec, but that there is a limit to how accurately it can be measured). We all learned that the Planck constant puts a limit on the accuracy of measurement of the product of position and momentum, or of energy and time (or I guess any two quantities that multiply or divide to give joulesXseconds as the dimension).

The point made to me was not that this is some math exercise, but rather reflects the granular structure of the universe; not that it might happen, but that it actually does happen that way.

One of the big holdups to unification, as I understand it, is precisely this problem; relativity (gravity) sails along splendidly in its continuous frame, quantum mechanics does splendidly in its granular one. Physics has a strong yearning (with ample historical precident) for simplicity, and would like to see the reconciliation of the continuous/discontinuous.

On the other hand, maybe the two are really discrete at all possible energies. Which means force unification under a single set of equations would be impossible. Wouldn't that be a hoot.

(BTW, Asimov used this idea in his story "The Billiard Ball". )

I just looked over that article that pmcolt linked, and I see no mention of that.

Has the article changed, or are you referring to a different article, or have I missed something?

This is where I pulled that out of the article, specific points are boldface:



If time is not quantified as previously established, is the unit which we used to define the quantization of time still valid? I did not believe that would be the case. As stated, its only an implication, so I was trying to phrase my question in a "what if" light.

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The last time I felt a warm fuzzy feeling, I was informed by my doctor that it was just gas.

You'd said " this challenges the idea of distorting time via relativity by undermining relativity's abilty to use time as a constant," but relativity doesn't require time to be of quanta. It actually supports relativity, by showing that all light travels at exactly the same speed.

So, I don't see any challenge to relativity at all.

I read the article, and I am confused as to how they got to their conclusion from the their premise. :-k It is my understanding that the "Airy disk" is an artifact of the optics of the telescope and that the history of the light is irrelevant to it. Can someone explain it to me? 8)

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T. Anderson

I think they are making some big assumptions about how quantized time would affect the speed of individual photons. If there was a difference--what percentage did the article mention?--the Airy disk would be disrupted. Big assumptions, probably unfounded.

I looked and found this article on the University of Alabama in Huntsville news site. The abstract of the authors' submission to Astrophysical Journal Letters is available here; fulltext seems to be limited to subscribers. That's all I've seen on the subject.

Kaptain K:

The 'airy disk' is simply a type of diffraction pattern.
Diffraction patterns (whtever the optics) are often used to deduce the characterictic nature of the radiation. Much interferometry is based upon that fact. (The airy pattern itself is a function of the frequency - optical resolution itself is determined by it ).

Not commonly realized is that for any particular frequency, diffraction patterns required coherent radiation for their formation. Without coherence the waves would spread out and the diff. pattern would not develope.

That's the basis of the report. If time is NOT quantized then the speed of all wavefronts during propogation can remain EXACTLY the same, producing the pattern. However, if time is quantized then each wavefront can VARY within a Planckian value of 10^-43 sec.; this small velocity spread causes a phase shift in the arrival of each wavefront which will blur (eliminate) the airy pattern.

In the short distance we are used to measuring this amount of variation would be undetectable. (In one second the shift could only be a max. of 10^-35 meters; totally undetectible).

However, over 10 billion years the authors have calculated that the phase shift would have spread enough to have eliminated the diffraction pattern.
However in light from stars 10 billion L.Y. away the pattern remains ....thus, the assumption of time quantization is false.

G^2

Gsquare,
I understand diffraction and Airy disks. That is not what bothers me. It is my understanding that , by definition, "c" is a constant in the absolute sense. Whether time is continuous or quantized should be irrelevent.

__________________
Any day you wake up on "the right side of the dirt" is a good day.

T. Anderson

By definition? I would have said, by assumption. But by our current best assumption. It's a premise of relativity, but it's been verified experimentally, to a pretty good precision.

PS: Or do you mean because the meter is defined so that it is always 1/299792458 of a lightsecond? That doesn't mean that c is a constant--it just means that the meter might not be constant!

kilopi,
By "by definition", I mean that if relativity is correct, then "c" is a constant. If "c" is not constant, then relativity needs to be superceded. 8)

__________________
Any day you wake up on "the right side of the dirt" is a good day.

T. Anderson

That's the whole point of the article; it IS relevent.....whatever the consequences to the assumptions of current theory. The character and history of light may be irrelevent to theory of relativity but it is NOT irrelevent to the production of the airy disk. That's the whole point....whatever its consequences.


If you say so. I certainly see no reason why relativity theory should be the final arbiter, .... it probably will be 'superceded'.

However if you go back and read my post (and the article) I think you will see that the physical evidence provides no threat to relativistic theory, rather the airy disc requires c to be EXACTLY constant over 10 billion years (or at least the relative phases be constant), and shows that it cannot vary even within Plankian time scale(10^-43 sec). :wink:

The thing that the evidence discredits is the Big Bang theory which is predicated upon quantized time. Astronomy Mag. deserves credit for courageously showing this as evidence that refutes BIg Bang theory.

G^2

Seems to be some discussion here about two different things regarding c as a constant. Again, it depends on whether we are talking about classical or quantum regimes (Time for a regime change? Sorry.)

My understanding of the classical formulation is that c is constant in a homogeneous medium, with the maximum c value being in empty (sic) space. The value of c will be lower in a matter medium (the refractive index is a measure of the ratio of c in two adjacent media, for example, but c is constant within the media themselves)

What the article seems to be discussing is whether there is a fundamental uncertainty (via Planck's constant) in the EXACT value of c (That is, can c be, in principle, mesured to infinite accuracy). They are using cosmological distances to attempt to magnify extremely small velocity variations due to quantum uncertainty, which would show up as phase changes in the wave front with consequent loss of coherence.

My analogy is similar to the problem of measuring distances between the lines of a ruler. For example, imagine you live on a block that is about one mile around. You would like to know the distance around your block to the nearest one hundredth of a mile, but the only measuring device you own is the odometer on your car, and it only measures to the nearest mile. What can you do?

Well, you can drive around the block one hundred times, then divide the mileage by 100. In a classical world, if you were an infinitely careful driver, each time you did that you would get the same answer. In the quantum world, each time you would get a slightly different answer, varying around the mean value.

What the article sems to be saying is that each trip gets exactly the same value (or so close to the same that it does not destroy coherence).

Again, the question comes back to why matter and energy would be quantized in a classical reference frame. How inelegant.

Mike, the authors are saying there are no velocity variations since the ary disk diffraction is evident...thus time is NOT quantized.

For those who are trying to defend relativity.... there is no need.

I've re-posted here the addition to my last post to Captain K to help clarify:

"However if you go back and read my post (and the article) I think you will see that the physical evidence provides no threat to relativistic theory, rather the airy disc requires c to be EXACTLY constant over 10 billion years (or at least the relative phases be constant), and shows that it cannot vary even within Plankian time scale(10^-43 sec).

The thing that the evidence discredits is the Big Bang theory which is predicated upon the assumption of quantized time. Astronomy Magazine deserves credit for courageously showing this as evidence that refutes BIg Bang theory. "

G^2

Exactly! This result has been around since February . Certainly Astronomy deserves credit for getting around to mentioning this, but the WMAP press conference was barely finished before the presses were rolling.

For those that are interested in the technical paper Lieu and Hillman is found at the Los Alamos Preprint server and a separate study that confirms their result was conducted by Ragazzoni, Turatto, and Gaessler .

The key point about these results is that the Big Bang does not expect them. As the Astronomy and Spacedaily articles point out the Big Bang's current version requires time to become "fuzzy" beneath the Planck interval in order to avoid the "sticky" problem of an infinite density and temperature. So if there's no "fuzz" there's no "Bang" - at least as currently conceived.

Yes, yes. My paragraph should have concluded with, 'since decoherence was not found, there are no detectable velocity variations; time is not quantized at the Planck level.' Sorry I didn't make that clear. Like 'Michelson set out to measure ether drift with his interferometer...' and forgetting to note that '...and he found none.'

Nevertheless, I don't see this as any more astonishing than the infinite charge density of an electron treated as a mathematical point. We don't go around saying electrons have been proven not to exist.

And forgive me, but I don't see anything courageous about Astronomy publishing a recap of the news. I mean, it's news, it's unexpected, it's cool in the extreme! Because it conflicts with the current scientific thinking?What could be better?

Yes, Mike; I think that's a great way of putting it. And the analogy with M & M is appropriate; sometimes its the negative experimental results that have the greatest impact on dissolving misconceptions.....

Physical data shows that electrons with infinite charge densities don't exist (no matter what your math theories say); likewise physical data has shown that Big Bang theory with its required infinities could not have been correct.

G^2

[quote="dgruss23"]Thanks for the affirmation, dgruss, and for the report by Ragozonni et al.
It takes me awhile to get around to reviewing 'everything'. By the way, I keep thinking this evidence will also bear more heavily on QED. Any ideas where continuous (non Planckian) time would require alterations of other fundamental eqns.?

He, He
How about:
No quantum time past = No Big Blast :P :-({|=

G^2

I really must try to finish my thought processes before pressing submit.

No, of course they don't. The simplistic point approximation is in conflict with observation. Therefore, the simplistic model is wrong. Although 'incomplete' strikes me as correct and in sync with the philosophy of inquiry (along the lines of Newtonian physics being 'incomplete' instead of wrong). Like when I was studying gas kinetics in grad school and learning the incrementally more accurate constructs that were developed (my education ended at RRKM, so I don't know where it's at right now).

But infinities strike me as our warning posts in theory. They scream either 'wrong!' or 'incomplete!' Quantum mechanics came out of the infinities of the mathematical treatment of blackbody radiation (ultraviolet catastrophe) conflicting with observation.

Likewise, "...physical data has shown that Big Bang theory with its required infinities could not have been correct." If the data hold up, I agree the statement as a whole is correct. But this does not show that the Big Bang theory (as a description of a physical phenomenon) is incorrect, just that the current descriptive synthesis needs work.

NB: I read the quote as implying that the new observations call the Big Bang theory ITSELF into doubt, not the math underpinnings. If I misinterpreted, I apologize in advance.

This was a simple empirical result. The images are "fuzzy" or they're not "fuzzy". Turns out they are NOT "fuzzy". It will be interesting to see what observations could possible reverse this result. Are we to conclude that the images are crystal clear because we have a poor quality space telescope and that upon the use of a better space telescope the clear images will turn fuzzy?

Please carefully read the last 4 paragraphs of the February SpaceDaily article I linked to. If time doesn't become fuzzy, then the Big Bang faces a "sticky" problem of infinite density and temperature. Theorists "invoked" the Planck time to avoid this problem. Just as inflation was "invoked" to explain the incredible smoothness of the microwave background.

A few years ago I suggested to a researcher that "An epicycle cannot be disproven, it can only be proven." Thus it seems to be with the Big Bang. It is pretty pointless to say the Big Bang is wrong because there is always a new version around the corner.

Hey, dgruss23, I'm here to learn, not to get people angry!

You wrote:

No (although I can't resist noting we had a poor quality space telescope where the fuzzy images turned crystal clear). I do ask that for something as fundamental as these results imply that additional data be collected and analyzed and cross-checked. Preferably by a different group on a different instrument. It's what we do in the lab here when we get wild results. Empirical results aren't always simple (For example, off the top of my head, what if spacetime is quantized at the string level instead of the Planck level? Is that 'small enough' to make these results indistinguishable from a true continnum?)

I did. Again. And I agree! That was pretty much my whole reason for starting this thread in the first place. It goes back to my original question: how will we reconcile quantized matter/energy with a possible continuous spacetime? Does this imply that a single unified field theory is inherently impossible? I was kinda hoping the commentary would be in this direction, as the implications are pretty... big.

I confess I'm not sure what you mean here. It's pretty hard to prove the nonexistence of something (as in, I have a tail, but only when I'm not looking). Are you saying that the basic idea of the Big Bang is wrong and cosmologists are just going through handwaving exercises?

Maybe I never stated it explicitly, but my own read on available evidence to date is that the Giant Space Kablooie is the best overall construct to explain many different strands of data. If there's a better explanation, bring it on!

Well, I hope I didn’t give that impression! I’m not angry. Did I sound that cranky?

Good point!

That has been done with the study by Ragazzoni et al I linked to above.

That is true. But cosmology has become too narrow in focus. How many cosmologists are genuinely willing to objectively consider solutions to these sorts of problems that do not involve a Big Bang? I don’t know the answer, but the published literature suggests the number is small.

That is an interesting question. I don’t know the answer.

No – certainly not handwaving. All the pursuits out there to resolve the Big Bang’s problems are worthwhile theoretical and observational exercises. The problem I have is that it is the view of many that the Big Bang is “proven”. As I asked above – how many astronomers are willing to consider, let alone commit to researching Big Bang alternatives.

Yet there are plenty of grounds for considering alternatives. IMO astronomers have committed to the Big Bang and the expanding universe concept too soon. Consider the problems that arise from the interpretation that redshifts result from expansion and resulting need for the universe to have originated in a singularity:

Matter-Antimatter problem: This is an observational contradiction with the Big Bang. There has been some discussion about Kaon decay and CP viotions as the solution, but as it stands the observed dominance of matter in the universe is an observational contradiction to the Big Bang.

Smoothness of Microwave Background: The CMB is of course hailed as one of the 3 pillars of the Big Bang, but the Inflation epicycle is required to explain the smoothness of the Big Bang. So in other words, the extreme smoothness of the CMB is an observational contradiction with the Big Bang concept. It is claimed that the CMB could only be due to a Big Bang, but Narlikar and others have proposed an alternate mechanism that involves thermalization from graphite and iron whiskers.

Cosmological Dark Matter Composition: Inflation requires a flat universe which means that astronomers assess the contents of the universe from a model dependent approach. Instead of surveying what is there – observationally, the assumption/requirement is that the total matter energy content in the universe must add up to what is needed for a flat universe. This requires that the universe be about 23% non-baryonic dark matter according to the recent WMAP results.

Now I started a thread on Baryonic dark matter in the Against the Mainstream forum. The point of which was to note recent research results which suggest that the dark matter in spiral galaxies may be entirely in the form of cold molecular gas clouds in the halo and an extended disk. I noted some studies that affirm this is possible. And what is the response to that: The dark matter cannot be all baryonic because the Big Bang requires that the dark matter be mostly non-baryonic. So here we have yet another case where the theory drives observations rather than the other way around. But IF the dark matter turns out to be entirely Baryonic, there is another contradiction with the Big Bang. In fact the baryonic dark matter content of spiral galaxies is an important test of the Big Bang. If additional galaxies are shown to have enough molecular H2 to account for the dark matter (as in NGC 891) then the Big Bang would be contradicted.

Recently it was shown that elliptical galaxies lack dark matter. This actually makes sense if the dark matter is baryonic because ellipticals have used up most of their gas/dust. If the dark matter is baryonic gas/dust then we would expect elliptical galaxies to have very little dark matter. But in the standard Big Bang view they have tried to explain that result by assuming that the dark matter is being stripped from these ellipticals in clusters. One then has to wonder why it is NOT completely stripped from the spirals in the cores of these clusters.

Redshift Anomalies: Here is a case where handwaving is occurring. Halton Arp has presented a viable case for the existence of extreme redshift anomalies and intrinsic redshifts. I will not go into all of that here because I’ve discussed it on other threads – but this evidence is not seriously considered because it violates the Big Bang’s assumption that redshifts are due to expansion (yet another case of theory being given favor over observational results).

Quantization of redshifts has been found in quasars, normal galaxies, and even the lower z absorption systems in quasar spectra!

Recently a thread was started by someone that thought the angular two-point correlation would disprove Arp. The only study I was able find on the matter looked at the quasar distribution in the Virgo cluster region and found that there was a correlation on angular scales from 5 to 40 arc min between quasars and Virgo cluster galaxies, but no correlation between quasars and background galaxies. This study was published in 1995 and nobody has refuted it.

NGC 7603 provides another recent example that confirms many aspects of Arp’s model.

My view on this is that the Big Bang could be correct, but it has enough serious problems such as the results you started this thread about that the alternatives should be given a closer look. The problem is that a person involved in research is often too busy with their own work to have time to find out about the alternatives. There are numerous misconceptions about Arp’s model. I’ve had to clear up a number of them on this board.

But your question is not about any of this but whether or not a unified field theory is possible given these results. I don’t want to hijack this thread so if anybody wants to debate any of the points I’ve made here we probably should move to a new thread in ATM - unless Mike Alexander wants to continue it here.

Mike, Do I sound angry?

Degruss re: were you angry?

No, and I apologize. (Looking back I realize I was doing a verbal Rorshach test on myself; reading emotional content into emotionally neutral statements. The only thing I can think of is that I hurt my hip climbing around the Montana badlands on vacation looking for fossils and the ibuprofen hadn't kicked in yet. I think I was the one being cranky)

I actually like very much your idea of a new thread discussing the consequences of the observations brought up here, and would be pleased if you started one. My only suggestion is that it doesn't belong in ATM, but rather GeneralA. As a newbie I'm still trying to catch on to the shades of difference between the two (The extremes are rather obvious, but the overlap portion is fuzzy. Maybe quantized at the Planck length :roll: .) I'll be reading and kibitzing as necessary.