Does the Photon Defy the Rules of Special Relativity?

[mpolo]

Is it fair to say that the photon does not follow the rules of Special Relativity? I ask this because the photon relative to all other frames of reference has zero mass even though it is traveling at the speed of light. If we increase the speed of any other particle to the speed of light its mass will increase tremendously as its speed approaches the speed of light. The one exception seems to be the neutrino. It also seems not to have much mass and I assume is also moving at the speed of light.

 

[Ibix]

There is no problem with special relativity here. You are confusing invariant mass and total energy.

If by "mass" you mean "invariant mass" then yes, photons have zero invariant mass (also known as "rest mass", although that's a silly term in this context because light cannot be at rest). But the invariant mass of massive particles does not change with speed.

If by "mass" you mean "relativistic mass" (aka total energy) then yes, massive particles' total energy increases with their speed. But photons do not have zero energy.

In short, you are comparing the total energy ("relativistic mass") of one thing to the rest mass of another. The behaviours are different because they are different things.

This is one of the reasons why modern sources discourage the use of "relativistic mass" for anything. Use "mass" to mean "invariant mass" and "total energy" to mean "total energy" and you won't end up with this confusion of masses.

 

[phinds]

A massive confusion for sure.

 

[Ibix]

A massive confusion for sure.

Don't make light of this topic!

 

[Nugatory]

The one exception seems to be the neutrino. It also seems not to have much mass and I assume is also moving at the speed of light.

They don't have much rest mass, but they have some. They're fast, but they don't quite move at the speed of light relative to any observer.

 

[mpolo]

Good explanations. Thanks. I re-read the explanations of mass again and this is very helpful.
Good humor too. If light cannot be at rest then, why can't light stop? By what mechanism does it stay in perpetual motion? This is a mystery to me. I don't believe I have ever read an explanation for that.

 

[Ibix]

By what mechanism does it stay in perpetual motion?

Newton's first law, basically. Why would it stop? Unless it collides with something of course.

 

[mpolo]

So you are saying that photons continue to move only because of momentum and inertia. If I am understanding you correctly. That can't be right. Photons hit things all the time yet we never see photons slowed down by such events. They are absorbed most of the time but sometimes they hit things and are deflected. They still manage to come out of the collision moving at the same rate. I just can't see Newton's law having anything to do with the constancy of light.

 

[sophiecentaur]

I don't believe I have ever read an explanation for that.

It's a property of all waves, actually. If they stop moving, they are no longer waves because energy is not being transferred.

 

[Ibix]

So you are saying that photons continue to move only because of momentum and inertia. If I am understanding you correctly. That can't be right.

Why not? It applies to everything else.

I'm being a bit too glib here, though. The other thing going on is that massless objects not traveling at lightspeed is a contradiction in terms in relativity.

Photons hit things all the time yet we never see photons slowed down by such events. They are absorbed most of the time but sometimes they hit things and are deflected.

Here you aren't talking about why they carry on in a straight line at the same speed. You're talking about interactions between quantum phenomena and "hit and bounced" is, I am told, not even close to a correct description. I don't pretend to understand exactly how photons' interactions with other particles work. But that wasn't what you appeared to be asking.

 

[mpolo]

Hmm To me the photon is not a wave. It's structure is wavelike. The problem with saying its a wave is the evidence from experiments that I have read says it is a thing that is a particle and a wave. If we test it to see its wavelike properties we get confirmation that it is a wave. If we test it to see if it has particle type properties it behaves as a particle. But a photon is not like an ocean wave as those type of waves are the type of waves that spreads out and requires a medium. Since as I understand it mainstream science does not believe that space is a medium the photon can't really be a wave because there is no medium. It seems to me we have a contradiction in thought. We describe the photon as a wave and moves by virtue of momentum. Yet every example of things that move in that way and in a wave like form do this within a medium of gas or fluid without exception. A medium is required.

So what mainstream science is saying is we have the photon that is a wave but it does not move in a medium. I say what's waving? I guess I am to assume that it moves through a complete void made of nothing. If that is the case which I doubt is a correct assumption., then we would have particles and such moving through space that is made of nothing. If particles are moving within space which is a container made of nothing then the particles would also have to be made of nothing. So now mainstream science has abstracted everything into math with no meaning or description of objects. None of this is sensible. So you can see why a novice like myself has trouble understanding this or making sense of it. I guess that the next argument would be to use, is that Quantum Mechanics really does not make sense so neither does the Universe. That is not an acceptable explanation.

So far what I am getting is that the photon is a wave and a particle. Which I do believe is correct. But it is a wave that travels at a constant rate of speed at precisely the same speed every time. How does the Universe do that. If photons were being ejected by something you would think they would not all be ejected at the same exact speed. It would be like an ocean with all the waves moving at the same exact rate of motion. That does not happen.

I am thinking the only way the photon could always travel at the exact same rate is that it must be traveling in a self propelled manner by virtue of its internal structure. It makes no sense for photons to be moving as the result of momentum. If you throw a hardball through the air that hardball is traveling because of momentum. The cause of photon motion is definitely not momentum. Mother nature does not throw all fastballs.

I think that the photon is a particle because it has a persistent shape but at the same time its has a surface topology that undulates which gives it its wavelike behavior. I also think that the photon must be made of something because it is a persistent object that can be detected

Furthermore the photon is a transverse wave which I have come to understand occurs only in a medium that is a solid. Since we know that the photon is persistent in form and is a transverse wave, that strongly suggests that it is traveling within a solid. Anything that is wavelike requires a medium. So I am thinking it must be traveling in some sort of medium. That's what the evidence suggests. This is my made up thinking based on what I have read.

I apologize for the rant but surely you can see my dilemma. What mainstream science states about our reality makes no sense. I am thinking to hard and I need to go play some video games. Thanks for the explanations. At least I understand what you guys are saying. I just don't agree with explanation.

 

[phinds]

Hmm To me the photon is not a wave. It's structure is wavelike. The problem with saying its a wave is the evidence from experiments that I have read says it is a thing that is a particle and a wave. If we test it to see its wavelike properties we get confirmation that it is a wave.If we test it to see if it has particle type properties it behaves as a particle.

Exactly. Because it is neither one. It is a quantum object.

If photons were being ejected by something you would think they would not all be ejected at the same exact speed.

Sure you might think that but if you then did experiments, you would find that you were wrong.

I think that the photon is a particle because it has a persistent shape

No, it does not. Light does not travel as a little ball, it travels as a wave.

I apologize for the rant but surely you can see my dilemma. What mainstream science states about our reality makes no sense.

That's often the case. We humans evolved in such as severely limited range of experience that things that are very large (cosmology) or very small (quantum mechanics) often to us "don't make sense" and "aren't intuitive" and so forth. That's the way the universe is. We've learned to get over it

 

[davenn]

Yet every example of things that move in that way and in a wave like form do this within a medium of gas or fluid without exception. A medium is required.

except an electromagnetic wave

So what mainstream science is saying is we have the photon that is a wave but it does not move in a medium. I say what's waving? I guess I am to assume that it moves through a complete void made of nothing. If that is the case which I doubt is a correct assumption., then we would have particles and such moving through space that is made of nothing. If particles are moving within space which is a container made of nothing then the particles would also have to be made of nothing.

An electromagnetic wave is self-sustaining. it doesn't need a medium through which to propagate

Photons are NOT like little bullets emitted by the source. The are the energy moderator/carrier of the electromagnetic wave.
Photons don't even really exist till they interact with something ... your eye, test gear etc

If photons were being ejected by something you would think they would not all be ejected at the same exact speed

if that were the case, then our universe would be a very different place. the speed of light/EM wave has been very well established as being constant in a vacuum or a given mediumDave

 

[Ibix]

So now mainstream science has abstracted everything into math with no meaning or description of objects

How is maths more abstract than the kind of verbal reasoning you are engaged in? The words you are using aren't actual photons. The concepts you're pushing around in your head aren't actual photons. They're simply descriptions, just as the maths is. And the huge advantage that maths has is that you can ground your theory in the numbers that your instruments spit out, rather than handwaving.

What mainstream science states about our reality makes no sense.

There's a difference between "I don't understand it" and "it makes no sense". You mean the former.

It makes no sense for photons to be moving as the result of momentum. If you throw a hardball through the air that hardball is traveling because of momentum. The cause of photon motion is definitely not momentum.

I don't understand why "a hardball is traveling because of momentum" is an acceptable answer but "a photon is traveling because of momentum" is not. Something that emits a photon will recoil, just as the pitcher will, due to the conservation of momentum. Unless it interacts with something, the photon will carry on in the same direction at the same speed, just like the ball.

The only different thing about light is that it always travels at the same speed in vacuum. This turns out to be equivalent to the statement that it's massless. You can construct a theory in which photons have mass and consequently do move at a range of speeds; the result is a modified form of Maxwell's equations. And here is the killer advantage of using maths: you can make quantitative predictions of what the world would be like if photons had mass. If memory serves the upper bound for photon mass consistent with experiment is currently around 10^-50kg. So we go with the simplest theory (massive photons make the maths a lot more complex for no detectable difference in the results) that is consistent with the available evidence: photons are massless.

 

[mpolo]

Okay a lot of responses. I will address them one at a time otherwise my response will grow to large.

Exactly. Because it is neither one. It is a quantum object.

@phinds Please define for me what a quantum Object is. Anyone else who wants to add or disagree with phinds definition feel free to jump in. I am very interested in the quantum mechanics arguments. I want to see if they can hold up. Next, why is the quantum view point of the microscopic world better than the classical view point, Objective reality. In other words prove to me that quantum objects are the correct description of reality. There must be some very good reason why mainstream science believes so strongly in the many and various Interpretations coming from Quantum Mechanics. There are so many interpretations its hard to list them all. I promise we will eventually get back to the photon. All of these details of this discussion are related.

 

[Ibix]

why is the quantum view point of the microscopic world better than the classical view point,

You are typing your posts on a computer. This is made from transistors. Classically, there's no way for electrons to tunnel through the energy barrier in a transistor. Classically, therefore, your computer shouldn't work. Yet here you are...

 

[jbriggs444]

the classical view point, Objective reality

Objective reality (aka experiment) shows that classical mechanics is incorrect.

 

[berkeman]

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