Gamma-ray photon race ends in dead heat; Einstein wins this round

Oct 28, 2009
In this illustration, one photon (purple) carries a million times the energy of another (yellow). Some theorists predict travel delays for higher-energy photons, which interact more strongly with the proposed frothy nature of space-time. Yet Fermi data on two photons from a gamma-ray burst fail to show this effect, eliminating some approaches to a new theory of gravity. Credit: NASA/Sonoma State University/Aurore Simonnet

Racing across the universe for the last 7.3 billion years, two gamma-ray photons arrived at NASA's orbiting Fermi Gamma-ray Space Telescope within nine-tenths of a second of one another. The dead-heat finish may stoke the fires of debate among physicists over Einstein's special theory of relativity because one of the photons possessed a million times more energy than the other.

For Einstein's theory, that's no problem. In his vision of the structure of space and time, unified as space-time, all forms of - , radio waves, infrared, visible light and - are reckoned to travel through the vacuum of space at the same speed, no matter how energetic. But in some of the new theories of gravity, space-time is considered to have a "shifting, frothy structure" when viewed at a scale trillions of times smaller than an electron. Some of those models predict that such a foamy texture ought to slow down the higher-energy gamma-ray relative to the lower energy one. Clearly, it did not.

Even in the world of high-energy particle physics, where a minute deviation can sometimes make a massive difference, nine-tenths of a second spread over more than 7 billion years is so small that the difference is likely due to the detailed processes of the gamma-ray burst rather than confirming any modification of Einstein's ideas.

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Credit: NASA/Sonoma State University/Aurore Simonnet

"This measurement eliminates any approach to a new that predicts a strong energy-dependent change in the ," said Peter Michelson, professor of physics at Stanford University and principal investigator for Fermi's Large Area Telescope (LAT), which detected the gamma-ray photons on May 10. "To one part in 100 million billion, these two photons traveled at the same speed. Einstein still rules."

Michelson is one of the authors of a paper that details the research, published online Oct. 28 by Nature.

Physicists have yearned for years to develop a unifying theory of how the universe works. But no one has been able to come up with one that brings all four of the fundamental forces in the universe into one tent. The Standard Model of particle physics, which was well developed by the end of the 1970s, is considered to have succeeded in unifying three of the four: electromagnetism; the "strong force" (which holds nuclei together inside atoms); and the "weak force" (which is responsible for radioactive decay, among other things.) But in the Standard Model, gravity has always been the odd man out, never quite fitting in. Though a host of theories have been advanced, none has been shown successful.

But by the same token, Einstein's theories of relativity also fail to unify the four forces.

"Physicists would like to replace Einstein's vision of gravity - as expressed in his relativity theories - with something that handles all fundamental forces," Michelson said. "There are many ideas, but few ways to test them."

The two photons provided rare experimental evidence about the structure of space-time. Whether the evidence will prove sufficient to settle any debates remains to be seen.

The photons were launched on their pan-galactic marathon during a short gamma-ray burst, an outpouring of radiation likely generated by the collision of two neutron stars, the densest known objects in the universe.

A neutron star is created when a massive star collapses in on itself in an explosion called a supernova. The neutron star forms in the core as matter is compressed to the point where it is typically about 10 miles in diameter, yet contains more mass than our sun. When two such dense objects collide, the energy released in a gamma-ray burst can be millions of times brighter than the entire Milky Way, albeit only briefly. The burst (designated GRB 090510) that sent the two photons on their way lasted 2.1 seconds.

Source: Stanford University (news : web)

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Alizee
Oct 28, 2009
This comment has been removed by a moderator.
brant
1.3 / 5 (4) Oct 28, 2009
"nine-tenths of a second spread over more than 7 billion years is so small that the difference is likely due to the detailed processes of the gamma-ray burst rather than confirming any modification of Einstein's ideas."

Plasma pinches have that profile. This is only slightly different than the merging of two bodies theory.
out7x
1 / 5 (2) Oct 29, 2009
0.9 seconds eliminates what quantum foam model???
Ethelred
5 / 5 (1) Oct 29, 2009
Any quantum foam model that has actual numbers, I suspect. That is, the Alizee, Alexa No Numbers Ever Model will continue to have every bit as much numerical support as it ever did.

None.

Exactly the same as The String Hypothesis which actually does have numbers. Only unlike Alexa-Alizee it too many rather than none at all.

Alizee:
Neutrinos trailed the visible light of 1987A by many hours. So if they preceded gamma rays, in any particular instance, it is likely due to the source being both much closer than the Magellanic Clouds and generated before the gamma rays.

Ethelred
Alexa
1 / 5 (2) Oct 29, 2009
..String Hypothesis which actually does have numbers...
String theory has no numbers in this extent - it simply considers, light is spreading in invariant speed through vacuum, being based on special relativity theory (between others)
Ethelred
5 / 5 (3) Oct 29, 2009
Based on General Relativity is a bit more accurate. For instance gravitational lensing can be involved. A gamma ray burst that is affected by such a lens could tell us more.

Of course there is no String Theory since, technically anyway, it doesn't yet tell us anything about the universe that can separate it from the Standard Model. So there is no way to take it out of the hypotheses stage.

Maybe someday.

The point I was making is that Aetherwave Theory ISN'T theory anymore than String Theory is theory. One is a hypothesis. The other is a vague, variable, highly amorphous concept in search of a hypothesis.

Both tell us nothing about the Universe. At least nothing that anyone can test.

GR has been tested and so far fits the evidence. This gamma ray data fits GR exceeding well so there is no need to suppose exotic vortexes. Now if you can find an reason for a vortex occurring and calculate a dispersal curve that could be a point in your favor with enough data.

Ethelred
Alexa
1 / 5 (1) Oct 29, 2009
This gamma ray data fits GR exceeding well
GR doesn't require light to spread in constant speed, as such requirement doesn't belong between GR postulates. The absence of gamma ray dispersion violates quantum mechanics due the presence of microwave background, instead. High energy photons should materialize with microwave photons more often then the low energy photons, thus forming particle-antiparticle pairs temporarily. These pairs cannot move by luminal speed. In this way, the absence of gamma ray dispersion maybe fits special relativity, but it violates another theories and Aether wave Theory has nothing to do with it.
Alexa
1 / 5 (1) Oct 29, 2009
.Now if you can find an reason for a vortex occurring...
Special relativity is relevant for flat space-time only with no microwave background and it describes light wave speed - not the speed of light photons. At the presence of microwave photons the result may be different. In fact, it should be - and the formation of vortex solitons is one of possible explanations. We didn't measure absolute light speed during gamma ray flash, only relative speed difference between gamma rays of different frequency - so it's still possible, gama ray flash propagates in highly subluminal speed through vacuum as a whole.
gmurphy
3.7 / 5 (3) Oct 29, 2009
Just some background info, the particular theory being disproved here is called Loop Quantum Gravity http://en.wikiped..._gravity While these experimental results have disproved the theory, at least it was able to provide testable predictions
Alexa
2 / 5 (3) Oct 29, 2009
the particular theory being disproved here is called Loop Quantum Gravity
It was rather so called double relativity (DSR, DSR2) proposed by Lee Smolin and Maguejio:
http://arxiv.org/.../0209264

Loop Quantum Gravity doesn't predict Lorentz symmetry violation in this case.
http://arxiv.org/.../0702016

Because prof. Smolin is an author of both theories, many people are connecting LQG with Lorentz speed violation, but it's incorrect interpretation. I'm explaining it on my blog.
MrGrynch
1 / 5 (4) Oct 29, 2009
In my developing theory of vacuum mechanics, this result is not surprising. The vacuum is an elastic propagation medium (not a 'foam') consisting of structure units. In order for energy to propagate through the vacuum, it must exert a force upon its constituent structure units. At a critical distance the force quantizes due to the granularity of this vacuum medium. The vacuum then reflexes, propelling the quantized particle (photon in this case) to the next vacuum structure unit to repeat the process (propagation). A more energetic photon involves more structure units in its propagation, but also gets a stronger reflex force, negating any effects due to 'size' of the photon.
Ethelred
5 / 5 (2) Oct 29, 2009
GR doesn't require light to spread in constant speed, as such requirement doesn't belong between GR postulates.

It has nothing in it to cause the speed of light to be affected by its energy level. If light WAS effected by its energy level then GR would be violated.
The absence of gamma ray dispersion violates quantum mechanics due the presence of microwave background

False
High energy photons should materialize with microwave photons more often then the low energy photons

False

Microwave photons are inherently lower energy than Gamma rays. The energy of any photon is directly related to its frequency/wavelength.
thus forming particle-antiparticle pairs temporarily.

Temporary yes. But that is the end of the gamma ray, permanently. So it won't cause a dispersion of the time of arrival since it won't arrive. It may affect the energy distribution.
but it violates another theories

False
Aether wave Theory has nothing to do with it

True

Ethelred
Nik_2213
1 / 5 (1) Oct 29, 2009
MrGrynch, does your model provide for both the wave and particle duality of photons ? Also, if your vacuum 'recoils', can it be leveraged ?
Ethelred
5 / 5 (2) Oct 29, 2009
Special relativity is relevant for flat space-time only with no microwave background

I WAS talking about GR not SR so that is irrelevant. So is the microwave background.
describes light wave speed - not the speed of light photons.

Same thing in a vacuum. You do know that SR is a subset of GR don't you? You sure aren't acting like it.
At the presence of microwave photons the result may be different.

Light waves don't interact with each other that way. Something to do with Spin.
and the formation of vortex solitons is one of possible explanations.

And hand waving is another. At least you seem to fond of it anyway.
We didn't measure absolute light speed during gamma ray flash,

True. It was arrival times. Which are certainly effect by departure times if the velocity is the same.
so it's still possible, gamma ray flash propagates in highly subluminal speed through vacuum as a whole.

Its possible that wishing works. Neither has evidence.

Ethelred
Alexa
1 / 5 (1) Oct 29, 2009
Microwave photons are inherently lower energy than Gamma rays.
Two photons always materialize in presence of external fields. Such field can provide neighboring photon of microwave background radiation. The so called GZK limit has the same origin - it results into complete dispersion of ultrahigh energy photons in vacuum.
..Temporary yes. But that is the end of the gamma ray, permanently..
If particle-antiparticle pair forms only 0.0000001% of total gamma photon life, it still means, such photon cannot propagate by speed of light completely, because material particles always propagate in subluminal speed - just because of Special Relativity. Anyway, it's not my intention to force you my truth - the future experiments will show us, who was right in this case.
Alexa
1 / 5 (1) Oct 29, 2009
The formation of boson solitons is quite general phenomena, in fact. Whole atom or Earth planet can be considered as a dense cluster of various bosons of very different wavelengths. Nevertheless, atoms or Earth still propagates through vacuum as a single body, just because lighter bosons are revolving centers inside of this cluster along longer path, thus compensating the effect of dispersion. I presume, formation of gamma ray clusters is the effect of the very same category - they can serve as an prototype for all heavier particles.

The trick is, many gamma ray flashes disperse fast - only those, which contain correct mixture of photons of proper wavelengths can travel across whole universe - so they can be observed at Earth at distance. It's an example of evolution of energy.
Neither has evidence
It has an evidence. Shorth distance gamma ray flashes are quite dispersive with compare to very distant ones and neutrinos often advance them.
Ethelred
5 / 5 (2) Oct 29, 2009
If particle-antiparticle pair forms only 0.0000001% of total gamma photon life,


Its not a percentage situation. Its an end of existence.

If a gamma ray produces a particle/anti-particle pair it is no longer a gamma ray and therefor will not arrive here. Thus it does not contribute to the measurement of gamma rays here.

To put it another way the gamma ray has to arrive for it to be detected. It can't arrive if it becomes a pair of particles before detection. Therefor pair production will not effect the arrival time since it won't arrive.

Ethelred
Alexa
1 / 5 (2) Oct 29, 2009
I'd recommend to read at least five ORIGINAL articles about gamma ray flashes to get a general picture of what is going on. If you would read only abstracts from popular on-line journals, like physorg, you'll always forced to wait, what more educated people will invent for you.
Ethelred
5 / 5 (2) Oct 29, 2009
Shorth distance gamma ray flashes are quite dispersive with compare to very distant ones and neutrinos often advance them.


Neutrinos have mass. Gamma rays don't. Therefor the only way for a neutrino to arrive before gamma rays is for them to generated first or for the gamma rays that were created at the same time to be blocked. Which fits the known causes of gamma rays and neutrinos.

Both can be created in violent events deep inside massive objects or on the surface of white dwarfs. However gamma rays cannot escape from the interiors of massive objects or even a dense accumulation of hydrogen on a white dwarf, in a straight line. Neutrinos can.

Since the events you mention are near, the difference in escape time is not overwhelmed by the higher velocity of the gamma rays after they finally escape.

Ethelred
Alexa
1 / 5 (3) Oct 29, 2009
Neutrinos have mass. Gamma rays don't.
During gamma ray flash the energy corresponding mass of Sun is released in a single moment. Can you imagine, where such mass gets lost? Whether it evaporates at place into nothing?

I know, many textbooks are memorizing like parrots, photons have no mass, only momentum. But you cannot believe in every nonsense from textbooks blindly - or you become religious parrot as well.
Ethelred
5 / 5 (2) Oct 29, 2009
Can you imagine, where such mass gets lost?


It isn't lost. Its dispersed as energy and gas. A tiny amount is converted to neutrinos.

A photons mass is its energy. As in E=MC2.

If you want to claim that photons have mass that is unrelated to its frequency then you have a to prove it. After all this time someone should have noticed. YOU should found something lurking in someones work by now. So I will go on the standard idea that a photon's mass is due to its energy.

Religion is right out. I will stick with being an Agnostic as that is all the evidence supports.

Ethelred
Alexa
1 / 5 (3) Oct 29, 2009
If a gamma ray produces a particle/anti-particle pair it is no longer a gamma ray and therefore will not arrive here.
Not at all. Resulting particle-antiparticle pair is mostly of opposite charge (like electron-positron) - so it gets attracted each other and recombines back again into pair of gamma ray. You'll notice any change, in fact.
Alexa
1 / 5 (3) Oct 29, 2009
If you want to claim that photons have mass that is unrelated to its frequency then you have a to prove it
Not at all - the mass of photons related to their energy by E= hf formula of quantum mechanics is quite sufficient to keep gamma photons together and to enable them in propagation like single swarm (well, not quite - but this is detail of too low level for You for now). In first approximation you can imagine, photons are kept together in gamma ray flash by their own gravity, thus fooling observers believing in special relativity blindly. I even presume, some other foreign photons may get trapped into cluster from outside.

But if you want to believe in general relativity, no one prohibits you in it. The phenomena described is just a result of general relativity - but it's not a product of flat space-time, but a product of many subtle space-time deforms, resulting from cosmic microwave background fluctuations.
Alexa
1 / 5 (3) Oct 29, 2009
I will stick with being an Agnostic as that is all the evidence supports
But you're still believer - in negation of my explanation. Popper's methodology is quite symmetrical in this point. If you believe in something, you're expected to give an evidence. If you don't believe in something, you're expected to support it by arguments as well. In general, being Agnostic is suboptimal strategy for invention of new theories.
Ethelred
4.5 / 5 (2) Oct 29, 2009
so it gets attracted each other and recombines back again into pair of gamma ray.


Which goes in a random direction. Therefor not in a straight line so we don't detect it.

Ethelred
Ethelred
5 / 5 (2) Oct 29, 2009
Not at all - the mass of photons related to their energy


Thanks but I already said that. I just used a different formula.

ut this is detail of too low level for You for now)


Too much hand waving anyway. Just how short are your arms that you think can't see them waving?

n first approximation you can imagine, photons are kept together in gamma ray flash by their own gravity,


Do you practice hand waving at beauty pageants?

I even presume, some other foreign photons may get trapped into cluster from outside.


Presume all you want. I prefer evidence.

But if you want to believe in general relativity, no one prohibits you in it.


The evidence doesn't prohibit even you from GR. Just your religion.

Two can play that game and since I use evidence and you wave your hands and call it a theory, you are the one with a religion.

Ethelred
Alexa
1 / 5 (1) Oct 29, 2009
...Which goes in a random direction. Therefor not in a straight line..
Yes, this is what a dispersion is called and its true for materialization of photons of approximately same frequency.

But the pair formed by materialization of very heavy photon and very lightweight one has a nonzero momentum toward direction of original - so after annihilation it continues in original line of travel and lightweight photon is restored. Macroscopically the gamma ray photon remains only slightly deflected from its path by spacetime deform of lightweight photon like by tiny gravitational lens.
Husky
1 / 5 (1) Oct 29, 2009
can they also rule out the slight possibillity that the high energetic photon got a headstart and was send earlier, but was chased by a faster moving lower energy particle e.g. gammaburst afterglow?
Ethelred
5 / 5 (2) Oct 29, 2009
But you're still believer - in negation of my explanation.

In negation of your hand waving and in agreement with actual evidence. So its not religion on my part. Your wild speculation doesn't qualify as explanations.
If you believe in something, you're expected to give an evidence.

I am waiting for yours. Mine is all over the Universe. Heck the GPS system wouldn't work if GR was significantly wrong.
In general, being Agnostic is suboptimal strategy for invention of new theories.

I know that English isn't your first language but you really need to look at the definitions of Religion and Agnostics before you make things up next time. It would really help if you used actual English words instead of learning them from Creationists.

Agnostic is the optimum for all non-religions thinking. It avoids the dogmatism of Atheism. I go on evidence and reason. Not hand waving and wishful thinking.

Ethelred
Alexa
1 / 5 (1) Oct 29, 2009
..can they also rule out the slight possibillity..
Of course not, all explanations are still possible. We just need more data about gamma ray flashes from different distances. Single photon doesn't count as an evidence at all.
Alexa
1 / 5 (2) Oct 29, 2009
..Mine is all over the Universe..
Nope, you're operating by General Relativity of pure flat space-time. Which doesn't exist in Universe, in fact. Universe is full of background fluctuations and every detailed theory should take account into it less or more later.
Ethelred
5 / 5 (2) Oct 29, 2009
Yes, this is what a dispersion is called


The article is about dispersion IN TIME. Not space.

so after annihilation it continues in original line of travel


Would you care to actually give a link that supports that statement? Not a link to your site by the way but someone independent. Without hand waving and with evidence.

Ethelred
Alexa
1 / 5 (2) Oct 29, 2009
Would you care to actually give a link that supports that statement?
Yep, for example here:

http://tinyurl.com/yzkldl6

But it's quite logical. What would you expect, when heavy and light photon annihilate and restore back? Would you expect symmetric dispersion of energy? This would violate momentum conservation law.
The article is about dispersion IN TIME. Not space.
Jeez, photons are moving by (nearly) speed of light. Every dispersion in space results into dispersion in time, too.
Ethelred
5 / 5 (2) Oct 29, 2009
Nope, you're operating by General Relativity of pure flat space-time.

You do know that GR deals with CURVED SPACE don't you? I did mention that the involvement of a gravitational lens could produce a lot more information.

So don't put words in my mouth. Or rather on the net and claim I said them.
Universe is full of background fluctuations and every detailed theory should take account into it less or more later.

So far all the evidence is that space is quite flat. The background fluctuations are about two parts in 10,000.

Ethelred
Ethelred
5 / 5 (2) Oct 29, 2009
Final-state NN-rescattering is found to be quite important and leads to a better agreement with existing experimental data.


Sorry but I am not paying to read that. The abstract doesn't support you in any case.

Was that a bluff? Or did you just not read the abstract.Its about spin in any case.

Ethelred
Alexa
1 / 5 (2) Oct 29, 2009
The background fluctuations are about two parts in 10,000.
? How did you get into such number?

Would you care to actually give a link that supports that statement? Not a link to your site by the way but someone independent. Without hand waving and with evidence.
Alexa
Oct 29, 2009
This comment has been removed by a moderator.
Ethelred
5 / 5 (2) Oct 29, 2009
Every dispersion in space results into dispersion in time, too.


How many times are you going to see the same thing and ignore it? Dispersal in SPACE results in NON DETECTION.

If it is dispersed in space it will not be detected on the same line as photons that are not dispersed.

We are talking about something that is billions of light years away. An exceedingly tiny deflection angle will result in missing the whole bloody galaxy much less our detectors.

Ethelred
Alexa
1 / 5 (4) Oct 29, 2009
Dispersal in SPACE results in NON DETECTION
Yes, at the case of single photon dispersion. But pair of photons gets always attracted each other during every collision by their mutual gravity. Again and again...
exceedingly tiny deflection angle
Gamma ray flash has a character of spherical envelope surrounding its source. It has nowhere to deflect from angle of its original direction.
Ethelred
5 / 5 (2) Oct 29, 2009
? How did you get into such number?


By using actual evidence. As in COBE.

http://map.gsfc.n...uct.html

And copying my style won't help you if you don't have evidence.

You're person of very thorough, even rigid thinking...;-)


Its the way I do it on most sites. I am not only person here that uses a signature. Most sites do it automatically.

There a several reasons that I use a signature. Its traditional in most forums. On some forums some wanker has already used Ethelred but doesn't post. For instance the physics forum that Physorg is linking too has such a non poster. Two posts and the second was his own reply to his first. On sites like that I use Ethlred with the middle E left out and then use the right spelling in my sig.

Thorough yes. Rigid, well the girls like it that way.

Use evidence and you won't have to descend to ad homonyms.

Ethelred
Alexa
1 / 5 (2) Oct 29, 2009
hot regions, shown in red, are 0.0002 Kelvin hotter than the cold regions
This has nothing to do with frequency of CMB photons. They're everywhere.
Ethelred
5 / 5 (2) Oct 29, 2009
But pair of photons gets always attracted each other during every collision by their mutual gravity. Again and again

Thus resulting in deflection again and again. Thus resulting in non-detection. Even assuming it happens as you describe, which is doubtful.
Gamma ray flash has a character of spherical envelope surrounding its source

This strikes me as a blatant case of Spherical Chicken thinking.
has nowhere to deflect from angle of its original direction.

If it is traveling along a 7 billion light year long line between the source and the Earth it has seven billions light years of VOLUME to deflect into. That is quite a large sphere and the Earth is an exceeding tiny portion of it. The only light that is going to reach is light that was emitted in the direction of that line and is UNDEFLECTED along the way. Pair production will result in deflection.

Claiming that the mutual gravitational attraction between photon is significant is quite an imagination.

Ethelred
Ethelred
5 / 5 (2) Oct 29, 2009
This has nothing to do with frequency of CMB photons.


Of course not. Didn't claim it did. Nor is that what you asked for.

Interesting how you lose track of the discussion.

It has to do with your claim of non flat space. Evidence as opposed to bare faced claims unsupported anything except the waving of your hands. Apparently you think the wave length of your hands has something to do with the curvature of space.

Ethelred
Alexa
1 / 5 (3) Oct 29, 2009
Thus resulting in non-detection
This results in clusterization of gamma flash, in similar way, like formation of photons (soliton wave packets) occurs in vacuum.
It has to do with your claim of non flat space
You're talking about energy anisotropy of CMB, which is in 0.0002 Kelvin range. I'm talking about anisotropy (space-time curvature) of single CMB photon. For illustration: I can put many stones from altitude 10,0 +- 0.0002 meters to your head. These stones can still kill you safely - although their anisotropy in potential energy distribution remains quite low.
Truth
not rated yet Oct 29, 2009
Wow, my head is spinning from all the great discussions generated by this article. One gets more insight into physics by the commentators than by the articles themselves!

But now, a question please:

My understanding of partcile physics says that gamma rays, like any other photons of whatever energy, do not have mass or charge; hence, they cannot react with any other entity and can at most only be absorbed. Therefore, why did anyone expect to see any sort of glancing interaction with the "quantum foam", even if that foam created charged or uncharged virtual particles?
Alexa
1 / 5 (3) Oct 29, 2009
..photons of whatever energy, do not have mass or charge..
By quantum mechanics energy of photon is given by equation E = h*f, by relativity theory energy is equivalent mass by formula m = E/c^2 = hf/c^2. Why photon shouldn't have mass?

It seems - despite I'm aetherist - I'm still the only person, which/who believes in these equations here.
Ethelred
3.7 / 5 (3) Oct 29, 2009
It seems - despite I'm aetherist - I'm still the only person, which/who believes in these equations here.

Perhaps if you weren't a HandWavist you would have noticed that I have pointed out the photons have energy and therefor mass.

Twice already.

This is the third time.

Learn to read.

Which is not the same as claiming you can't read.

You can.

You just don't.

Ethelred
Ethelred
5 / 5 (2) Oct 29, 2009
This results in clusterization of gamma flash, in similar way, like formation of photons (soliton wave packets) occurs in vacuum.

Lets see, non detection results in all that PLUS detection.

Amazing.

Thats multiple times you have made ludicrous conclusions based on NON_DETECTION.

Even by Physorg standards that is a high level of anti-achievement.
You're talking about energy anisotropy of CMB, which is in 0.0002 Kelvin range.

I am talking about your claims of fluctuations in the curvature of space. Which would show up in the CMB. And don't.
I'm talking about anisotropy (space-time curvature) of single CMB photon.

Your inventing things that don't exist. Unless of course you have EVIDENCE. Something you have yet to show.
These stones can still kill you safely

Really. Amazing. Safely killed.

And without any relevance at all as well.

Perhaps if you wave your hands faster and harder you can fly.

Your HandWave WAG has even less chance of flying.

Ethelred
Alexa
1 / 5 (2) Oct 30, 2009
..Thats multiple times you have made ludicrous conclusions based on NON_DETECTION....
Not at all. I'm doing extrapolations of many gamma rays observations, in fact. And taking many related phenomena into account, too. Whereas you're just extrapolating single photon observation by now.

Whole story started before two years already, when MKN501 event was observed. This gamma ray burst occurred at much closer proximity, then the GRB090510 - and MKN501's high energy photons were delayed by more then thirty seconds.

This sounds a bit strange, doesn't it?
..conclusions based on NON_DETECTION....
This is quite common approach in physics. Negative result is result, too. Just try to remember the extrapolations of negative result of Michelson-Morley experiment.
denijane
5 / 5 (1) Oct 30, 2009
"a short gamma-ray burst, an outpouring of radiation likely generated by the collision of two neutron stars, the densest known objects in the universe."
As far as I know, there is no confirmation of what exactly produces GRBs. So, this line should include at least one "probably" or "most likely" if it intends to be scientifically correct.
Alexa
1 / 5 (2) Oct 30, 2009
The point is, we still don't know, if Lorentz symmetry was really broken. What we only know is, whole cluster of photons arrived at single moment.

But we still don't know, if this cluster moved in speed of light, the speed of microwaves in particular. For example, whole Earth planet is composed of bosons of different wavelengths, but it still propagates through vacuum as a single body by subluminal speed. So it violates Lorentz symmetry heavilly, although every boson in it travels along complex spiral path, along which Lorentz symmetry is maintained. The funniest part is, both interpretations are correct at the single moment.
Alexa
1 / 5 (2) Oct 30, 2009
Inside of solitons wave packets the waves of different wavelengths are propagating like single object - although in isolated state such waves would spread in different speed. The soliton mechanism is quite common in physics - it just requires to choose proper combinations of wavelengths in distribution of photons, which is closely related to gamma function and golden mean ratio. Of course, such combination of photons would be quite rare - but from the very same reason it would be the very last combination, which could travel through the whole universe without apparent dispersion - so we can detect it at its very end.

What we are facing is sort of natural selection process - just applied to cluster of gamma photons.
Alexa
1 / 5 (2) Oct 30, 2009
Another point is closely related to recent metamaterial models of vacuum (you know, all these "black holes for light"). In general, metamaterial is basically kind of foam, in which positive and negative curvatures are (nearly) balanced. The trick is, people are choosing such structure of vacuum automatically by observation at large distance, because just this structure remains the least dispersive environment possible.

This model has even its own analogy from common life. During heavy rain dense water droplets are forming kind of metamaterial foam in atmosphere. When we are observing rainbow, we can often see the dark area between primary and secondary rainbows. It corresponds the angle of observation, in which the dispersion of light by inner and outer surfaces of water droplets becomes balanced. In such direction particle environment slows down the energy spreading - but it still doesn't exhibit the dispersion.
Alexa
1 / 5 (2) Oct 30, 2009
The point is, inside of such environment light is spreading in slowest possible speed too, so that this environment appears as huge as possible from perspective of observer inside it.

In my opinion, this is exactly the case of vacuum, which we are observing at cosmic distances via gamma ray bursts. This geometrical model of vacuum goes pretty deep, as it explains, why universe exhibits universal symmetry violation, omni-directional space-time expansion, event horizons and other theoretical stuffs. But it explains too, how is it possible, we cannot observe dispersion of gamma ray photons JUST at large distances.

Thank you for your attention and sorry for flooding.
superhuman
5 / 5 (1) Nov 01, 2009
But now, a question please:

My understanding of partcile physics says that gamma rays, like any other photons of whatever energy, do not have mass or charge; hence, they cannot react with any other entity and can at most only be absorbed. Therefore, why did anyone expect to see any sort of glancing interaction with the "quantum foam", even if that foam created charged or uncharged virtual particles?


Photons have zero rest mass but non-zero relativistic mass, usually what is meant by mass is rest mass.

Photons can react with charged particles without being absorbed, google Compton scattering for example.

As for the interaction with the "quantum foam" the prediction was based on the postulated shape of spacetime on extremely small scales, photons are affected by spacetime, for example massive bodies such as stars induce enough curvature in spacetime to lead to observable bending of photons paths. I don't know however how exactly pair creation comes into this picture.
MorituriMax
not rated yet Nov 01, 2009
Why was there even a 9/10ths of a second difference between them?

Sorry if I missed it in an earlier post, way too much stuff to go through before work.

Thanks.
lomed
5 / 5 (1) Nov 01, 2009
Why was there even a 9/10ths of a second difference between them?
From the Physorg article:
the difference is likely due to the detailed processes of the gamma-ray burst
Superhuman brings up an interesting point. If any of the photons had been involved with pair production, they would have had to have interacted with matter. Thus, even if the products recombined to produce another gamma ray there is no reason for it to be emitted in any particular direction or even have the same energy as the original (since energy and momentum would have been carried away by the matter that facilitated the pair production). I think this is what Ethelred meant when he said pair production would deflect photons. Since the only way photons interact with each other directly is via gravity, and this interaction is extremely weak, the only reasonable way for a group of photons to arrive from a source far away is to have traveled at the same speed the entire way (same path+time --> same speed)
Alexa
1 / 5 (3) Nov 01, 2009
You just reinvented my proposal, which extrapolated this model in recent 10+ posts. This just illustrates, people are reading only last post, so that discussions can continue infinitelly. Simmilar situation exists in mainstream science - this is what the re-search is called.

Because photons are of different energy, resulting cluster wouldn't be homogeneous, the more heavier photons would go to the center of cluster, thus mimicking tiny gallaxy or planetary system. Maybe the lone high energy photon was trapped into photon cluster from outside, maybe it even served as a nuclei of cluster simmilar to condensation of water droplets from atmosphere.

In general, cluster formation doesn't mean, Lorentz invariance is maintained, because the whole cluster could move in slightly subluminal speed.

The reason, why Nature didn't considered this possibility is probably in widespread belief, photons have no mass, only momentum.

http://www.physli...e270.cfm
Alizee
Nov 01, 2009
This comment has been removed by a moderator.
baudrunner
1 / 5 (1) Nov 02, 2009
It may be that the "slower" of the photons had a longer distance to travel. Nine billion light years is a long, long ways away. A minor diversion within the topographical space-time continuum could result in a major difference over the long term.

The acceleration of gravity on an object only appears to be independent of the mass of the object. After all, inertia - resistence to a change in motion - is much greater for a more massive object. This has implications for the photon background acting on the photonic wavelength. After all, energy "is" mass.
Slotin
1 / 5 (1) Nov 02, 2009
..A minor diversion within the topographical space-time continuum could result in a major difference over the long term...
Article point was, it didn't result - so we are forced to improve this model - or throw it at all. Every planet or star suffers by this paradox too - it consists of many bosons of different wavelengths, but it still propagates through vacuum like single body. The explanation would be probably the very same.

Observation of gamma rays is significant in its combination of extremelly high energy density, which propagates at extremelly high distance (combination of extreme high and low space-time curvatures). Nowhere in terresterial lab such combination can be achieved. This makes research of gamma rays so usefull in understanding of fundamental principles, which are driving observable Universe.
HenkZw
not rated yet Nov 03, 2009
I still don't understand why these 2 photons are 'related'. Couldn't they have been created
at different times at the source ? It may be
clear to all the professionals here, but the
article seemed sparse on this.
Ethelred
5 / 5 (1) Nov 05, 2009
One of the guesses for gamma ray burst is the merger of Black Holes.Such an event is should generate very high energy gamma rays such as those detected. The merger of the black holes would take time but a very short period of time.

So yes they could easily have been generated at different times. Nine tenths of second is close enough together to have been created in such a merger. There is no need to suppose that they had to have been created simultaneously. The article was clear enough on that point.

Link to an article about the same paper.
http://arstechnic...urst.ars

It seems pretty clear that the event was of a very short duration but long enough for a one second window for the generation of high energy photons.

In other words they could indeed have been generated at different times as long as you consider an interval of about one second to be at different times. Seems that most do.

Ethelred
Alexa
1 / 5 (1) Nov 08, 2009
BTW Condensation of gamma ray photons in field of microwave photons is semi-classical example of tachyon condensation of open strings into D-strings, as proposed first by Sen in 1999 at scope of Open String Field Theory, introduced by Witten in 1986. In another way, string theorists are fighting against demonstration of low energy analogy of model, proposed by another string theorists. This example demonstrates clearly, how deeply are some string theorists separated from reality, which they're trying to describe. Picture bellow illustrates, how open strings condense into closed one:

http://www.aether...ring.gif

Here we can met another low-energy analogy of closed D-strings, which are attached to space-time brane in so-called the Falaco solitons, which are spreading along density gradient, which is forming water surface.

http://www.youtub...wZ39EDmw