An Idea

[Profpat]

[Fredrick]

Welcome back Fredrick

Thank you, Pat. I know I have missed out on many good posts, and I also missed being part of this thread. Not knowing in how far I will be able to keep up to date on what is being discussed, I do apologize for my cameo behavior.

Since I do not see replies from you (but I haven't yet sorted through all posts) about this photon question, can I ask you (and others) to comment on the question what happens to the photon from distant source A moving through a million photons that are all moving away in more or less one direction from in-between source B?

[Profpat]

I don't really know Fredrick. Has there been any empirical studies on it? Are your thoughts on it based on logic alone? I know photons can interact with electrons. But I don't know if a massless photon is able to interact with another massless photon.

Best,

Pat

P.S.

I did find this on the internet, so with your scenario, of godzillions, probably yes.

What happens if two photons crash, can they?

• 3 years ago

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by Steve M Member since: September 23, 2006 Total points: 2857 (Level 4)

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Best Answer - Chosen by Asker

Yes they can. Photons interact under the usual rules of quantum electrodynamics although as they carry no charge, photon-photon interactions are not a first-order process and so the probabily of the interaction is quite small. A simple example is pair-production in the electric field of an atomic nucleus, which is the dominant interaction for photon energies above 10MeV.

[Fredrick]

I did find this on the internet, so with your scenario, of godzillions, probably yes.

What happens if two photons crash, can they?
Best Answer - Chosen by Asker

Yes they can. Photons interact under the usual rules of quantum electrodynamics although as they carry no charge, photon-photon interactions are not a first-order process and so the probability of the interaction is quite small. A simple example is pair-production in the electric field of an atomic nucleus, which is the dominant interaction for photon energies above 10MeV.

Thank you, Pat. It makes me feel good that you consider it possible. And yes, the delivery is based on logic, but also on everything else we have learned about the universe for what happens when two entities of the same make meet up.

We know that matter of the same kind does ordinarily not annihilate each other (unless additional requirements are met); they have that specific kind of interaction that is appropriate for their kind, but not annihilation.

Diamond for instance does cut diamond, but only if we actively apply one diamond as a cutter to the other diamond. No other condition than applied pressure would make diamond cut diamond. So it depends on the situation what the result will be.

Since in this question there are no other entities around than photons moving through space, we do not need to be involved with how photons interact with other entities. They are in an environment of their own and are following certain paths. In that sense the reply you found online is helpful, but not providing much more than some insight.

I am quite certain no empirical studies have taken place; it would require having tools in place that go themselves as fast as the speed of light just to be present at the moment of sideway interaction to discover how two photons would then interact. Quite impossible, no? Also, one photon bumping into another photon is not the same as a single photon moving through an environment of many photons that all move sideways in the same direction.

But I also do not think empirical studies are required to understand the fundamental question: can the result we see be explained by classical mechanics or must we (as the answer chosen by Asker indicates) explain this in quantum-electrodynamic words only. I don't think this is required and the result of the pushing of many photons on the single deviating photon would be a classic mechanical answer.

The underlying reason for this question would be finding support for the idea that classical mechanics is still the only guiding overall framework in our universe, and that quantum mechanics finds its validity then only at the specific realities of this classical framework. This would then help establish that there is a fundamental separation between knowledge about the normal conditions and knowledge about the special conditions.

[Profpat]

Hi Fredrick;

My belief is that, quantum physics, classical physics and relativistic physics, is all the same physics. I think they are all reconcilable. They are just measuring different aspects of the same reality. The difference is how big and how fast. Determinism appears to fit the Neutonian classical world, but probability theory rules the quantum world. This I reconcile using the game of craps, with only one or a few tosses the outcome is random and probablilstic, but with many tosses the long term outcome becomes what appears to be deterministic. In relativistic physics the emphasis is on the velocity, not the size necessarily. I believe the quantum physics is close to being reconciled with relativistic physics, using string theory. What of course is needed is quantum gravity.

Just some thoughts.

Pat

P.S. You are right when matter smashes into matter there is no annihilation, but when matter smashes into antimatter there is. Remember the photon being chargeless and massless is it's own antiphoton.

[Profpat]

I guess when waves collide you can get anything from cancellation to amplification.

[Profpat]

A little more research on photon collision:

Question

Why don't photons collide with each other when traveling towards each other?

Asked by: James Tanquary

Answer

Photons in free space act almost exclusively as waves. Therefore, when they cross paths they merely set up an interference pattern for the very brief time of their interaction. No energy is exchanged and the quantum state of each photon is unchanged after they pass each other.

This interference pattern is akin to ripples on water that approach each other, form an interference pattern of peaks and troughs and then continue on their way.

If matter is present where the photons cross, non-linear effects caused by accelerated electric charges may allow the photons to interact. This interaction could be considered a collision of sorts, resulting in exchange of energies with many possible outcomes.

One such outcome is called frequency doubling, where two photons are combined to form one photon at twice the frequency.

Answered by: Scott Wilber, President, ComScire - Quantum World Corporation

I guess from this answer there would be no change of direction to the photons.

[JAK]

...
Photons in free space act almost exclusively as waves. Therefore, when they cross paths they merely set up an interference pattern for the very brief time of their interaction. No energy is exchanged and the quantum state of each photon is unchanged after they pass each other.
...

I read an article a few years ago that when two lasers were pointed at each other, the creation of an electron and a positron were among the results.

Unfortunately, I did not clip it for use later, and I don't remember where I read it. (Google might find it.)

[dipayankar]

Well there is supposed to be a mass particle (Higgs boson was it?). What ever happened to that?

Good question. Most of the mass of the proton/neutron doesn't come from the mass of the 3 quarks but rather from the interaction of those 3 quarks. I believe the same is true for quarks and strings, i.e. most of the mass of the quark doesn't come from the string but in the interaction of the vibrating localized field the closed string creates. ~ open no field, O closed field created.

P.S. Welcome back Fredrick

[austintorn@aol.com]

The Higgs:

http://www.youtube.com/watch?v=TnpICoXRU80