This paper raises some questions regarding general theory of relativity like: (i) the theory predicts ‘expansion of space’ between the galaxies; but the space within the galaxy is not expanding, because galaxy is a gravitationally-bound-structure. The question raised here is: If so, then what happens at the edge of a galaxy whose external space is expanding but the space within is not expanding? Is there a smooth transition from expanding to non-expanding space? And what happens to the cosmologically red-shifted inter-galactic-photons when they enter our milky-way galaxy from expanding outer-space to less-and-less expanding space within our galaxy? (ii) According to general relativity the planets, like the earth, orbit around the Sun, because the space around the Sun has got curved; and the planets are in inertial-motion traveling along the geodesic path. Now the question raised here is: Inertial-motion of a body can be at any speed. Can the planets travel along the geodesic-path at any speed they like? Can they take a coffee-brake and then proceed further? (iii) According to general relativity there is a distance at which rate of expansion of space is equal to the speed of light; and the speed of light is always the same, 3 x 10^8 meters per second. The question raised here is: Since the speed of light is the same in expanding as well as non-expanding space; and f . λ = c , i.e. the product of frequency (f) and wavelength (λ) is always equal to the speed of light (c); then the wavelength (λ) can increase only when frequency (f) gets reduced; and not because of expansion of space. Then in the second part of the paper it is shown that reduction in energy of ‘cosmologically red-shifting photons’ is strikingly equal to (G me mp / e^2) times the reduction in electrostatic potential-energy of an electron at the same distance D.