The Universe and Photons by Emmanuel Moulay

Dear Dan and Florin,

Thank you very much for your comments.

First, I answer the question of Florin. Gluons have no electric charge but a color charge. Photons have neither electric charge nor color charge. Actually, your question deals with the strong symmetry breaking in this framework. The Higgs mechanism, which is the electroweak symmetry breaking, explains the generation of masses for the W±, and Z weak gauge bosons and thus the difference between photons and the weak gauge bosons. Definitely, we need a new mechanism to explain why gluons have a color charge (when interacting with quarks) contrary to photons in the framework of this essay. This refers to the problem of the strong symmetry breaking. I agree that the sentence "Then, gluons are freed from the grip of quarks and become photons." is not clear.

Dan, the fact that the photon can be the most fundamental element in the universe is an assumption. I try to explain some consequences of this assumption. Photons are described by the Quantum mechanics and play a large part in the theory of the General Relativity with the speed of light and the stress-energy tensor. If the photon is the most fundamental element of the universe, it means that the universe is discrete and continuous at the most fundamental level due to the wave particle duality. If photons can explain the 4 fundamental interactions, we don't need to put together the Quantum mechanics and the General relativity. Nevertheless, we have to explain the beginning of the universe with this fundamental element and this is the purpose of the first section "Photons and the Big Bang". Thank you for your encouragement.

Emmanuel Moulay

Dear Helmut,

I don't know your work but thank you for your encouragement.

Dear Cristi,

Thank you very much for your interesting comments and summary of my essay. I would like to clarify two things.

The first one is that the Hawking radiation is not supposed to be made of photons only but of general radiations. Thus, we can imagine that some particles as electron can emerge from the horizon of black holes. Nevertheless, it is probably impossible for the Planck horizon due to the conservation laws. Indeed, if an electron goes out of a black hole, it implies that the black hole have a charge that changes. If there is a first original radiation at the Planck epoch, it cannot be charged due to the conservation laws and because the Planck horizon does not cut the space in two, like horizons of black holes. For these reasons, I think that photons are a good candidate to be at the origin of a first radiation that removes the initial singularity.

The second one concerns the gauge bosons. To my mind, gauge bosons were more an evolution of photons due to the symmetry breakings than a stable product of pair productions. Nevertheless, with your point of view, we can define a fundamental particle (boson and fermion) as the stable product of a pair production in two-photon collisions. The stability of reactions depends on the temperature, as proposed with the symmetry breakings. Definitely, this is a good suggestion compatible with the Feynman diagrams.

Emmanuel

Dear Constantin,

Yes, it is an independent research and yes I make a classical physical assumption in this essay. I think that photons can help us to remove the initial singularity, contrary to other particles (see my previous post).

Thank you for your remarks.

Emmanuel

Dear Cristi,

This is a key point of the essay. To answer to this question, we have to come back to the foundations of the General Relativity and time. The General Relativity stipulates that we live on a four dimensional Lorentzian manifold whose metric, which is the link between the time variable and the space variables, is a solution of the Einstein field equations. What is exactly this time variable? I have written an eprint available here http://cel.archives-ouvertes.fr/cel-00511837 where I try to explain that the time variable represents the possibility of motion for the matter relative to the speed of light (which is the possibility of motion of photons) along the geodesics defined by a metric. If there are photons only at the Planck epoch, the meaning of the time variable falls down due to the fact that photons have no proper time. I agree that it is always possible to calculate the solutions of the Einstein field equations for a large quantity of energy, but the time variable has no meaning with photons only. It is exactly as if you calculate the solution of a differential equation describing the evolution of the quantity of fish on a planet which has no water at the beginning of its evolution. In a certain kind, I think that the physical reality of photons can protect us again the initial mathematical singularity of the Einstein field equations.

Emmanuel

Dear Dan,

Your post is very important. Indeed, the notion of time is fundamental in order to develop a physical theory. We have to come back to an old debate between Albert Einstein and Ernst Mach concerning the relativity. Ernst Mach thought that all was relative (speed but also acceleration) whereas Einstein has postulated that all is relative with respect to the speed of light and thus nothing can go faster than the speed of light. For another reason, Albert Einstein has introduced the notion of light quanta: the photon. Concerning time, there is a similar debate. You can think that time is totally relative (see the fantastic book of Julian Barbour "The End of Time") or you can think, as me, that time is defined relative to the speed of light. I have developed this idea and I have given a definition of time: "The time coordinate ct represents the possibility of motion for the matter relative to the speed of light c along the geodesics defined by a metric g" (see http://cel.archives-ouvertes.fr/cel-00511837) and then time comes from the time coordinate but it is not a fundamental variable of the General Relativity. Then I have tried to extend the idea of relativity with respect to photons to the fundamental particles. Actually, you can obtain all the fundamental particles starting with photons only, as an evolution of photons depending on the temperature (see the previous posts). Somehow, the fundamental particles are defined relative to photons (I have made a mistake concerning the bosons corrected by Cristi). The next step was to postulate that the fundamental element in the universe is the photon. This is a very different philosophy than the one of the Quantum Gravity, but this is the same goal. The last step is to see if there is a problem with the initial singularity. To my mind, this problem can be compared with the Hawking radiation. If you have only photons at the boundary of the Planck epoch, and with the previous definition of time, the notion of time falls down. Indeed, the notion of time starts with the first pair production at the boundary of the Planck epoch. The Planck area is well defined with known particles: the photons, but there is no time and thus the motion is not defined.

I will read your essay with pleasure.

Emmanuel

Dear Eckard,

In physics, proofs come from experiments, contrary to Mathematics. Thus, you obtain that a theory is checked with a certain degree of precision. Concerning the General Relativity, there are many papers showing that this theory is checked with a huge degree of precision (see for instance the works of Holger Müller at Berkeley).

Concerning the time travel, you have to define what time is. Based on the General Relativity, I have developed the idea that time is not fundamental in the General Relativity and comes from the time variable. The time variable represents the possibility of motion for the matter (the matter is all non zero mass objects) relative to the speed of light. Then, time comes from the possibility of motion. It is strange but there is no arrow of time at the fundamental level, only motions relative to the speed of light (or relative to photons which are the light quanta). Nevertheless, due to the second law of thermodynamics, some motions are not allowed. With this point of view, the time travel makes no sense. This is the motion relative to photons which is fundamental, not time, as usually defined.

Emmanuel

Dear Eckard,

I am not sure to understand what you mean. The Lorentz transformation is the mathematical way to explain how the speed of light was observed to be independent of the reference frame in the Special Relativity. I don't see any flaw in this theory. You can read the initial work of Henri Poincaré (or any book about the Special Relativity) to be convinced that the Lorentz transformation is the right way to express the fact that the speed of light is constant.

I think that the problem of unification you talk about is the one of the quantum gravity (unification of the General Relativity and the Quantum Mechanics). It is a very hard mathematical program with two main theories: the string theory and the loop quantum gravity. Actually, the fundamental questions are the unity of physics and the beginning of the universe. It is possible that a physical solution emerges from the quantum gravity program. As an alternative, I point out in my essay that we could answer to the previous fundamental questions if we make the assumption that the photon is the most fundamental element in the universe.

Emmanuel