Can FTL Travel be Achieved With Mass of a Photon?

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Lunct
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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?
 
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Lunct said:
can we make the mass of something less than a photon

Less than zero?
 
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Vanadium 50 said:
Less than zero?
surely a photon has somewhat of a mass because energy does have mass
 
Orodruin said:
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?
 
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Lunct said:
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.
 
Lunct said:
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.
 
Lunct said:
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.
 
okay a photon has no mas, can we get to the actual question now?
 
Lunct said:
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.
 
Greg Bernhardt said:
It has been answered and the answer is no

And with that, this thread is closed.
 
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