My question is probably basic at first view but I would like to really understand this in details. The way I understand the role of the phase in quantum mechanics is that as soon as we have a physical quantum state: $|\psi\rangle$, multiplying it by $e^{i \phi}$ doesn't change the physical state....

I don't really understand what is meant by curved space. Why does mass warp space? Why does curved space alter the velocity of a massive object? Normally to change an object's direction you have to apply some force to overcome inertia. So how does curved space do it? What is space anyway?! Layman...

Suppose a man is standing on a merry ground which is rotating with some speed, if he jumps out in the radial direction, then the rotation speed of the merry go round is unaffected. But I don't understand why should this be so? I saw this article discussing it, but they don't really explain what's...

We often discuss mass-density, charge-density, and other such functions: $\rho(x,y)$ for ultra-thin plates and $\rho(x,y,z)$ for 3-d objects. The units for the output of these functions say mass or charge/unit volume like $\frac{kg}{m^3}$ or $\frac{C}{m^3}$. I cannot comprehend a density at a sin...

So, based on this question, a molecule containing a radioactive atom will break when the atom decays. But suppose you need a lot energy to break the compound apart --- as in, more energy than the decay of the atom will release (obviously, a molecule this stable isn't actually possible... right?)....

We know about the general theory of relativity which is modern theory of gravitation. Einstein formed it by stating no action can be observed including gravitational force faster than speed of light. means gravitational force is not instantaneous so it shows if sun eventually disappears hypotheti...

The way I was taught QM (and perhaps most students around the world) is very weird. There is no intuitive explanations or understanding. Instead we were given a recipe how to quantize a classical theory, which is based on the rule of transforming all quantities to operators, and that Poisson brac...