I have been dealing with the following issue related to the Schwarzschild geometry recently. When expressed as: $$ ds^{2}=-\left(1-\frac{2GM}{r}\right)dt^{2}+\frac{1}{1-\frac{2GM}{r}}dr^{2}+d\Omega_{2}^{2}$$ one can find a Killing vector $\xi=\partial_{t}$, since there are no components of the me...

Isn't the Equivalence principle not quite true, technically speaking? A gravitational acceleration and an inertial acceleration are communicated very differently. A gravitational acceleration is communicated throughout your body and its stress is spread out in your body, whereas an inertial accel...

If I understand correctly polarisation of electromagnetic wave, two opposite phase wave of same polarisation can cancel each over, so the question is : As white light have all polarisation, all the wave are in equally direction around 360°, and as there is all phase, it should cancel all each ove...

Is it possible to have a capacitance in a system of two point charges? Since there is a potential energy between them and they both have charges then we can divide the charge by the potential and get capacitance. However, capacitance is supposed to depend only on geometry so should therefore be z...