Photon Rest Mass: How We Know & Mass While Moving

[bahamagreen]

When the photon develops a rest mass in a superconductor...

What happens to its relationship to c?
If an electron in the superconductor emits or absorbs a photon, does the photon with rest mass participating in that emission or absorption undergo a period of acceleration or deceleration?
Or is the photon emitted and absorbed instantly at full speed (in this case maybe < c)?

Or, is the photon now not "really" a photon, but something else?

 

[Paul Bauza]

Rest mass of Photon is 0.
My Q is: 1- why Photon speed is finite if does have no mass?
2- why light is curved passing Black Hole and if is curved because
warped space-time. (not it's mass) how Black Hole can warp Space-Time.
if Space-Time have no mass?

 

[Drakkith]

Rest mass of Photon is 0.
My Q is: 1- why Photon speed is finite if does have no mass?
2- why light is curved passing Black Hole and if is curved because
warped space-time. (not it's mass) how Black Hole can warp Space-Time.
if Space-Time have no mass?

The speed of light is simply the universal speed limit. Anything with 0 mass must travel at this speed.

A black hole has lots of mass, and since mass and energy warp spacetime it alters the path of the light passing nearby.

 

[PaulS1950]

Both space and time are affected by massive objects so it stands to reason that space/time would be affected by the black hole.

The speed of the photon and its energy are the cause of its emission. After it is emitted Its speed and energy levels are constant due to its velocity.

 

[atyy]

how Black Hole can warp Space-Time.
if Space-Time have no mass?

Matter has energy which causes spacetime curvature. However, spacetime can still be warped if there is no matter, because the equations governing spacetime's interaction with itself are nonlinear.

 

[Ozie Cucumber]

How did we come to the conclusion photon has no rest mass? Does photon have any mass(not talking about rest mass) while moving at usual c?

=ozie: Michelson and Moreley's experiment proved that no matter how a mobile point with a speed v is directed to the light source or run away from it, the speed of light is always the same! But the experiment (as the later experiments did) was based on the interfence between an direct light beam and reflected one. In my opinion this experiment has a limit because too small shift of interferences it is possible to escape to power resolution of the device. Some books presented the ideea of an estimated rest mass of photon of 10 to minus 47 kg ( 10-47kg). So we can conclude that the speed of let say 299000 km/s to be not sufficent to have a relativistic mass infinite! To such value it is posible that the shift of interference to be unobservable, the shift to be under the threshold of resoluition of device!