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Author Topic: How can photons travel at the speed of light?  (Read 2047 times)

Jimbee

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How can photons travel at the speed of light?
« on: 04/01/2016 08:35:46 »
Just one question I have always had. Why can photons go the speed of light?

Einstein proved light speed would require infinite energy to move infinite mass. And nowhere in the universe is there infinite energy.

Oh, I've heard some people say, photons have energy, but no mass. But that is ridiculous. Einstein showed energy is mass. And mass is energy. So there.

Also, while we're at it, why can't photons go faster than light? If they have no mass (which is what some of you will probably say), then it should be no problem. And then they could go back in time. Why not? I'd love to send a message back in time. Where I live, the jackpot for the multi-state lottery is \$300 Million+. You can guess what I would say.

And lastly, what do you call photons in Britain? It says in my Webster's dictionary that it is an American term (well, actually, it has a star by it--which is what that means). So what do you call a quanta of light in the UK? We just call them photons. I would be eager to hear what you all would say.

« Last Edit: 04/01/2016 16:56:37 by chris »

evan_au

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Re: Photons and the Speed of Light.
« Reply #1 on: 04/01/2016 09:11:05 »
Quote from: Jimbee
I've heard some people say, photons have energy, but no mass. But that is ridiculous. Einstein showed energy is mass. And mass is energy. So there.
The subtlety here is that photons have zero rest mass. If you could slow photons down to a stop in a vacuum, they would have zero energy and zero mass.

But in reality they do travel at c (in a vacuum), so they have finite energy which has an equivalent finite mass.

Quote
Einstein proved light speed would require infinite energy to move infinite mass. And nowhere in the universe is there infinite energy.
However, in this case it only takes a finite amount of energy to move zero mass at the speed of light.
And there are plenty of places in the universe that have finite energy available.

Quote
Also, while we're at it, why can't photons go faster than light? If they have no mass (which is what some of you will probably say), then it should be no problem.
As I understand it, it would take an infinite amount of energy to make light travel faster than the speed of light in a vacuum.

Quote
what do you call photons in Britain?
If have seen Britons calling them photons.

Ophiolite

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Re: Photons and the Speed of Light.
« Reply #2 on: 04/01/2016 09:29:53 »
Oh, I've heard some people say, photons have energy, but no mass. But that is ridiculous. Einstein showed energy is mass. And mass is energy. So there.
Given that many thousands of very intelligent individuals who have studied the matters, including several Nobel prize winners, have no difficulty in accepting this, don't you think it a little precipitate to say it is ridiculous. Have you considered that you might be wrong?

They are photons in the UK also. Perhaps your dictionary is identifying the country where the term originated.

puppypower

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Re: Photons and the Speed of Light.
« Reply #3 on: 04/01/2016 12:20:19 »
Photons travel at the speed of light, with the speed of light observed to be the same in all references. Photons also express finite attributes; wavelength and frequency, which are not the same in all references, but rather are inertial reference dependent. Different inertial references will see red and blue shifts of the energy, with all photons having the speed of light. Therefore, photons have two legs, one leg in the speed of light reference and one leg is in inertial reference dependent.

The easiest way to explain why photons travel at the speed of light and also have inertial attributes, is because the speed of light is the ground state of the universe. The speed of light is at lowest potential, which is why this is common to all references. The finite attributes of energy appear as a result of interaction of the ground state leg, with higher potential inertial reference.

You are assuming the conventional wisdom, that assumes matter and inertial defines the ground state. We need to gain energy to reach the speed of light. If this was true, since the speed of light is faster, it must have more potential (kinetic)energy. The question becomes, why does the photon keep moving, instead of wanting to slow down?

On the other hand, if you assume C is the ground state of the universe it should be common to all inertial references. The photon by moving at the speed of light is trying to stay at lowest potential. Since photons also interact with matter and inertial, these interactions can cause the photon to gain potential. Instead of slowing from C, the gains of potential is reflected in its finite leg. The result of the potential difference between the two legs is a cycling phenomena.

One way to see how the speed of light is the ground state is as follows. Say we started the universe with pure energy, without any matter or mass in the universe. In this case, the only references will be the speed of light reference, seen by each and every photon. If the energy is high enough, some photons will split into matter and anti-matter. Matter appear at the higher end of energy. Since matter and anti-matter can't move at the speed of light, even their inertial nature defines higher potential. These exist only at the highest energy range of photons, where photons split into matter/anti-matter.

Matter and anti-matter would like to annihilate and return to energy; lower potential back to photons and C reference. Say for some reason the anti-matter is taken away, so all we have left is the high potential matter, it that would like to return back to the energy and the C ground state, but now it lacks an easy path.

If you look at out universe, there is a net conversion of matter back to energy; fusion, since that is the direction of lowering potential; toward the C ground state of energy.

lightarrow

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Re: Photons and the Speed of Light.
« Reply #4 on: 04/01/2016 16:26:05 »
Oh, I've heard some people say, photons have energy, but no mass. But that is ridiculous. Einstein showed energy is mass. And mass is energy. So there.
No way! Einstein *has not* showed that. He has showed that a body which has energy E in a frame of reference where it doesn't move has also mass m related to it:
E(measured in a frame where body doesn't move) = mc2

You are just the billionth person which has been deceived about it from popular books.

--
lightarrow

jeffreyH

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Re: How can photons travel at the speed of light?
« Reply #5 on: 04/01/2016 18:41:23 »
Define mass. Where does it come form? How can it vary in magnitude with a change in velocity? What happens to it when it disappears into a black hole? Why does it insist on resisting a change in velocity? Why does gravity seem to have less of a problem accelerating the stuff? I think the confusion arises because people equate zero rest mass with non existence. That is not what it means. Just flick a light switch.

jeffreyH

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Re: How can photons travel at the speed of light?
« Reply #6 on: 04/01/2016 19:31:12 »

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Thebox

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Re: How can photons travel at the speed of light?
« Reply #7 on: 04/01/2016 22:55:51 »
Just one question I have always had. Why can photons go the speed of light?

You really have to ask that when you give the answer in the question?

I will re-arrange for you slightly

Why can Photons travel at the speed of Photons?

Hmmm, because  Photons are light.

Space Flow

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Re: How can photons travel at the speed of light?
« Reply #8 on: 05/01/2016 06:04:45 »
Quote from: Jimbee on 04 January 2016, 19:35:46
Oh, I've heard some people say, photons have energy, but no mass. But that is ridiculous. Einstein showed energy is mass. And mass is energy. So there.
No way! Einstein *has not* showed that. He has showed that a body which has energy E in a frame of reference where it doesn't move has also mass m related to it:
E(measured in a frame where body doesn't move) = mc2

You are just the billionth person which has been deceived about it from popular books.

--
lightarrow
Totally agree. Any gain can only be described from a relativist other frame. Never from one's own. So in a sense it is illusionary.
Take a cosmic ray coming at you at nearly the speed of light.
It wouldn't feel illusionary if it hit you.
But on the other hand, your relativistic added Mass wouldn't feel illusionary to that particle. It was standing around not feeling at all heavier not moving at all as far as it was concerned when you and your relativistic added mass slammed into it at nearly the speed of light.
So which one had put on the weight?
All that E=Mc^2 tells us, is that, to any mass you have to attach a certain amount of kinetic energy if, "you are in relative motion to it". Not extra Mass but the Kinetic equivalent of extra Mass.
We tend to interpret that as, "it being in relative motion to us".
I think it's called the anthropic principle. We don't like to admit to it, but it is.

alysdexia

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Re: How can photons travel at the speed of light?
« Reply #9 on: 09/01/2016 18:04:32 »
E = mc^2 no more means that vis and mass interconvert than V = abc means that volume and width interconvert.

One travels (< travail < trepale) on foot or by oar; motes and waves don't travel but go, fare, or wend.

Fast is not a speed; glue is fast, the opposite of free; motes are fleet; rockets are swift; birds are quick; pizza is speedy; deeds are hasty.

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Re: How can photons travel at the speed of light?
« Reply #9 on: 09/01/2016 18:04:32 »