B Can FTL Travel be Achieved With Mass of a Photon?

[Lunct]

Really silly question, but if we assume that our current science is correct, is it plausible that we can move faster than light in a vacuum? Say, for example, can we make the mass of something less than a photon so it then can it move faster than light in a vacuum.

I know this sounds like a stupid question but I always here "at the moment we don't have the technology to move faster than light", but I have always believed it is simply not possible. Is it possible?

 

[Vanadium 50]

can we make the mass of something less than a photon

Less than zero?

 

[Lunct]

Less than zero?

surely a photon has somewhat of a mass because energy does have mass

 

[Greg Bernhardt]

surely a photon has somewhat of a mass because energy does have mass

We have a nice FAQ here
https://www.physicsforums.com/insights/do-photons-have-mass/

Here is a nice long discussion to read up on
https://www.physicsforums.com/threads/do-photons-have-mass.536599/

 

[Lunct]

We have a nice FAQ here
https://www.physicsforums.com/insights/do-photons-have-mass/

Here is a nice long discussion to read up on
https://www.physicsforums.com/threads/do-photons-have-mass.536599/

so when a photon is moving is possesses mass

 

[Orodruin]

so when a photon is moving is possesses mass

No.

 

[Lunct]

No.

I can understand why it doesn't have a mass, it must have a mass. Maybe it is so small we can't possibly mesure it but it must have a mass. If it doesn't than why?

 

[Orodruin]

I can understand why it doesn't have a mass, it must have a mass

No. In fact, the photon having mass would directly violate gauge invariance of QED. Energy does not imply mass.

 

[Arman777]

I can understand why it doesn't have a mass, it must have a mass. Maybe it is so small we can't possibly mesure it but it must have a mass. If it doesn't than why?

Particle can't move with speed of light and also have some mass. That's just not possible due to relativistic effect.

 

[SiennaTheGr8]

I can understand why it doesn't have a mass, it must have a mass. Maybe it is so small we can't possibly mesure it but it must have a mass. If it doesn't than why?

In modern notation, Einstein's famous equation is actually $E_0 = mc^2$. Note the subscript! $E_0$ is rest energy, which is the energy that something has when it's at rest. A photon is never at rest (always moves at the speed of light), so it has zero rest energy (and therefore zero mass). Its energy is entirely kinetic.

 

[Lunct]

okay a photon has no mas, can we get to the actual question now?

 

[Greg Bernhardt]

okay a photon has no mas, can we get to the actual question now?

It has been answered and the answer is no

 

[Arman777]

Say, for example, can we make the mass of something less than a photon so it then can it move faster than light in a vacuum.

If photon has zero mass this doesn't make any sense.

Or in general, an object can't travel faster than the speed of light.

 

[PeterDonis]

It has been answered and the answer is no

And with that, this thread is closed.