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Is the relativistic energy-momentum relation fundamental? [duplicate]
The following relativistic energy-momentum relationship is taken to be fundamental:
$$E^2=p^2c^2+m_0^2c^4.\tag{1}$$
Let us specialize to massless particles ($m_0=0$) so that we have:
$$E=p\ c.\tag{2}$$...
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Mass density of photons in a refractive medium
The effective mass density of photons in a vacuum $\rho^{vac}_M$ is related to the photon energy density $\rho^{vac}_E$ by
$$\rho^{vac}_M=\frac{\rho^{vac}_E}{c^2}.$$
Is it true that the mass density ...
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Does $E^2=(mc^2)^2+(pc)^2$ hold for light travelling in an optically dense medium?
The rest mass of photon $m_0=0$ and photon travels at the speed of light in vacuum. So the energy of photon in vacuum is given by $$E_{vacuum}^2=(m_0c^2)^2+(pc)^2=(pc)^2$$ $$E_{vacuum}=pc=\gamma m_0c^...
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How is it possible for the wavelength of light to change in a medium?
So my physics class has just finished a long unit on optics while at the same time I've been trying to teach myself relativity. I admit my understanding is probably rudimentary, but I figured all the ...
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