Waste less time on Facebook — follow Brilliant.
×

Mass of photon and Einstein's theory of relativity

\(m=\frac {m_{0}}{\sqrt {1-\frac {v^{2}}{c^{2}}}}\)

As speed of light changes in a medium, should we change the denominator also?

If we dont change the denominator, then for a photon travelling with a high fraction of speed of light in a medium (less than c), mass should be defined, but it is not.

Note by Prince Loomba
1 month ago

No vote yet
1 vote

Comments

Sort by:

Top Newest

The speed of the photon is same regardless of the medium.

It is it's apparent speed that we observe (which is lower due to collisions with the particles of the medium).


Note: This argument holds for any mass less particle as well. Deeparaj Bhat · 4 weeks ago

Log in to reply

@Deeparaj Bhat The 2nd is not. Obvio the first is Prince Loomba · 3 weeks, 6 days ago

Log in to reply

@Prince Loomba I'm sorry, I don't understand what you're saying. Deeparaj Bhat · 3 weeks, 6 days ago

Log in to reply

@Deeparaj Bhat I am saying the first point is valid for all, for all particles it should be such. But the second point is for photon specially Prince Loomba · 3 weeks, 6 days ago

Log in to reply

@Prince Loomba As I am saying mass should be defined, which is not only in photon's case Prince Loomba · 3 weeks, 6 days ago

Log in to reply

@Prince Loomba Mass of what? The rest mass of the photon is zero. And the above formula is consistent with the fact that the moving mass of a photon is not defined. Deeparaj Bhat · 3 weeks, 6 days ago

Log in to reply

@Deeparaj Bhat If we change it according to refractive index, then only mass of photon will be undefined in all cases. Thats my point Prince Loomba · 3 weeks, 6 days ago

Log in to reply

×

Problem Loading...

Note Loading...

Set Loading...