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A thought experiment about light


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You really should have a reason why you don't trust relativity, because nearly any sane scientist does. This is because next to electrodynamics, it's one of the best tested theories we have in science. Going into physics discussions while admitting you have no respect for relativity is like a turkey voting for Christmas. 

So I can't possibly have a discussion with you on the subject, because you're not sane enough to trust what's known as fact and what you blindly, and mindlessly believe as a fiction.

As for a photon exerting momentum to a photon...  A photon may actually accelerate round curved trajectories, but it always moves at the speed of light, but these trajectories are measured only by two phenomenon, whether the light is blue or redshifted. This in itself is well tested. A photon has been well known to exert momentum on dust particles. But it cannot spontaneously exert momentum on a photon that any momentum exerted will make it exceed lightspeed. A photon cannot pick up speed in relativity, but it always has an acceleration. Rarely do photons interact with each other at all, but under the right circumstances and high enough energies, they can and will create a matter and antimatter pair. Learn about matters to which you wish to preach, before saying you don't trust them, because you'll get nowhere by doing so.

 

Edited by Dubbelosix
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We can get really technical and say light speed does vary in gravitational fields, we can say it acts like a refractive index, but it still moves at lightspeed regardless of how you shape it up. This is why special relativity is special, because we are talking about signals in a flat medium. It isn't generally true, as we find in GR where light is technically spatially variable. But one thing is certain, it's always measured as moving at light speed, it's spatially variably because the metric of spacetime itself is dynamic.

Edited by Dubbelosix
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It's important this whole idea of the medium being reclassified as arefractibe index, my written papers when into the question of whether black holes are essentially prisms and wave mechanics following the laws of optics in such a way that light can escape black holes. (The first person to recognise this type of model was Satori) I believe his name is, I don't have my papers to hand. We do impose in this scenario that light appears variable, but only because permeability and permittivity are the objects we use to define the index of refraction which varies significantly in gravitational fields so that the speed of light can only ever approach a limit, but never quite appear to reach zero speed. If course, it's speed hasn't varied at all, no more than it varies in water, since light is moving through a different thickness associated to any optical medium.

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Now, while light always propagates at the speed of light, the rule always holds only the physics may appear different,so long as we understand it as it applies to the medium in question. We can throw photons into carbon media and they act like heavy electron, their speed becomes measurably slower in that effect. Electrons moving in superconducting material often break the so called lightspeed barrier, while this all may seem like you can't trust relativity, it's actually within the laws of physics. Light will always be spatially variable in gravitational fields, and other media except for a vacuum that it must pass through. Spatial variability shouldn't be mistaken to meantime photon really has slowed down, or it would loose energy, and any photon escaping a prism of water would come put the end slower than it went in! But we don't measure that.

 

Here's a really good Forbes article for you to digest

https://www.forbes.com › sites
Web results
This Is How Physicists Trick Particles Into Going Faster Than Light

Edited by Dubbelosix
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13 hours ago, Dubbelosix said:

You really should have a reason why you don't trust relativity, because nearly any sane scientist does.

The reason why I don't believe in the theory of relativity is mainly because the phenomenon can be explained by the theory of relativity, and other theories can also explain it, and it is more reasonable.
Nowadays, the theory of relativity is more like religion than science. People who do not support the theory of relativity basically have no right to speak. Sane scientists are no less enthusiastic about the theory of relativity than priests preaching Catholicism, and they can't even insist on being objective.

If the momentum of a photon can be absorbed by others, can its speed be reduced?

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If there was another theory, I'd be aware of it. Relativity survives because it's the only theory which managed to produce explanations of reality in a testable way. No other theory will ever exceed it, perhaps only a theory which tweaks it, but only that. So this strange idea you have that theres some existing theory that does just as well or even better, is hogwash.

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On 4/18/2021 at 11:49 PM, Simon4159870717 said:

The reason why I don't believe in the theory of relativity is mainly because the phenomenon can be explained by the theory of relativity, and other theories can also explain it, and it is more reasonable.[/quote]

What theories are those?  Of course, there have been many corrections or variations of relativity but the basic concept has been verified by experiment after experiment.  When I was in college I remember being shown a new experiment, using lasers, fairly new at the time, that would given a more accurate test of relativity.


[quote]Nowadays, the theory of relativity is more like religion than science. People who do not support the theory of relativity basically have no right to speak.[/quote]

That's not how science works.  Every physicist knows that if he could publish an article giving a firmly established refutation of relativity he would become immediately famous.

[quote] Sane scientists are no less enthusiastic about the theory of relativity than priests preaching Catholicism, and they can't even insist on being objective.

If the momentum of a photon can be absorbed by others, can its speed be reduced?[/quote]

No, the photon simply ceases to exist.

 

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On 4/19/2021 at 6:49 AM, Simon4159870717 said:

The reason why I don't believe in the theory of relativity is mainly because the phenomenon can be explained by the theory of relativity, and other theories can also explain it, and it is more reasonable.
Nowadays, the theory of relativity is more like religion than science. People who do not support the theory of relativity basically have no right to speak. Sane scientists are no less enthusiastic about the theory of relativity than priests preaching Catholicism, and they can't even insist on being objective.

If the momentum of a photon can be absorbed by others, can its speed be reduced?

You don't believe in the theory of relativity, but you believe in photons.
I don't believe in both.
Why do you believe in photons?
How do you know that such particles exist?
What experimental evidence have you seen which tell you that those particles are reality?
Have you witnessed any experimental evidence personally?
I ask you the last question because people believe that light consists of colors, but many of them have never seen a real prism, not to speak about an experiment with it.
And if you begin to make experiments with prisms on your own, you will see that the Newton's theory is a huge crap. I have proved it and I am ready to go out on a public debate with whoever scientists or academics and I will put them all in my small pocket (that's a Macedonian proverb and means that I will beat them in a debate with arguments). But the debate should happen under one condition: for everything that is claimed in it, one should present the experiments live on the stage. Then we will see who tells reality and who tells FABLES.
See my articles about light and colors and tell me then that light consists of colors!
At the end, I ask you again:
Why do you believe in photons? 

P.S. Here are my articles for those who want to read them:
https://www.scienceforums.com/topic/37833-why-is-the-sky-blue-how-does-light-make-colors-appear/

https://www.scienceforums.com/topic/37887-what-is-an-achromatic-doublet/

https://www.scienceforums.com/topic/37922-the-greatest-hoax-in-the-history-of-science-part-1/

https://www.scienceforums.com/topic/37959-the-greatest-hoax-in-the-history-of-science-part-2/

 

Edited by MitkoGorgiev
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11 hours ago, MitkoGorgiev said:

Why do you believe in photons?

I never witnessed any experimental evidence personally. So I doubt everything.

I believe in photons because I think photon is the lowest unit of light. Light must be composed of something, and it's okay to call it a photon.

I am very interested in light, I will read your articles.

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5 hours ago, Simon4159870717 said:

I never witnessed any experimental evidence personally. So I doubt everything.

It is good to doubt many things, but it is not good to doubt everything.
For example, you cannot doubt that there is a magnetic field around the poles of a permanent magnet. Although you cannot see it, you cannot touch it, you cannot hear it etc., still, when you bring another magnet close to it, you feel the force. 
 

Quote

I believe in photons because I think photon is the lowest unit of light. Light must be composed of something, and it's okay to call it a photon.

Why must light be composed of something? Why must light have a lowest unit?
Let me ask you this: What is a magnetic (or electric) field composed of? What is the lowest unit of a magnetic field?
Or what is a gravitational field composed of? 
Of gravitons???!!!! 

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15 hours ago, MitkoGorgiev said:

Why must light be composed of something?

I have to say: Not everything must be composed of something.

Under the sun light, you can see your shade, that means sun light is blocked partially, so sun light is not a whole piece. Light from star take years to come to earth, even the star was gone, that means light can be separated from the resource. So I think light is composed by photons is reasonable.

Gravity is NOT composed by anything, gravity is just a phenomenon, not a substance.

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On 4/16/2021 at 5:45 PM, Dubbelosix said:

First of all, does light have inertia? The most simplest of model would say yes. In fact many books and scientists will tell you it has a mass. This is because it's energy has units of mass so we write for the mass of a photon

m = E/c^2

Why though when a photon is commonly said to have no mass at all? It may be faulty, but one school of thought will teach you that light has mass but no matter. There's a simple experiment which may support this. When a photon is absorbed by an atom, or any system, it contributes to the matter of the system. So technically speaking, some distinguish between mass and matter. So keep that under your hat.

On the other hand, the Sagnac effect does not prove directly the photon has inertia. Only that it makes a statement about how the photon is affected by a dynamic medium where gravity stretched space and rotating bodies pulls space in certain directions. 

Please provide your references to these many books and scientists who will tell you light has mass!

The energy and momentum of light are related by  E=pc . This is a special case of the relation E2=(pc)2 + (mc2)2 , which reduces to E= mc2 for massive particles at rest (p=0). Since light has no mass, only E=pc applies. This is known as the dispersion relation, which is the relationship between energy and momentum and has nothing to do with mass.

We have empirical evidence that this is correct  found in the so called “solar wind”, where light from the sun accelerates absorptive or reflective particles smaller than a certain (critical) size away from the sun, where particles that are too large experience a net attractive force and are pulled in by gravity more than they are pushed out by the light. Note that light transfers momentum proportional to the radius of the particle squared where gravitation exerts a force on the particle proportional to its radius cubed, so for tiny particles, light pressure wins where for larger ones gravitation wins!

As for light having inertia, one can argue either way; that it does or it doesn’t. What it boils down to is inertia does not seem to be a meaningful concept for a massless particle.

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You don't need to doubt experiments when others have done it for you. I'm going to diagnose this. Not only are you suffering from a complex science delusion. But you are ignoring incontrovertible evidence which you have ignorantly ignored. There's a narcissistic tendency going on. Because if you CAN'T SEE THE PARTICLE, look you'll always use this loophole - you can in fact see particles, we detected them all in accelerators. It's not a mass delusion, but rather a mass paranoia!

Edited by Dubbelosix
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