P.S. - Don't even try to solve these if you are a heart patient and want to live long, but if you do get the right answers then you get to take of loads of prizes (i.e. loads of respect in my eyes)
1) 1) What is the rest mass of a Photon? If non-zero, then how does Photon itself Travel at c in vacuum when particle nature dominates, since it will itself have some moving mass? If zero, than how does the gravitational pull of black hole attract it?
2) 2) It’s known that from every frame of reference a Photon always travels at c in vacuum. It’s somewhat an axiom, but what is the basis of this assumption?
3) 3) Nothing that acquires mass can reach or excel the speed of light. Then, what about particles like tachyon and muon. And is there some on-going experiments in CERN dealing with particles that can propagate at a speed greater than that of light? Also, do matter waves travel faster than light?
4) 4) By E=mc^2, mass and energy are two different forms of the same entity and are inter-convertible. So does it mean on losing energy on doing work, an object also loses its mass?
5) 5) There is virtually nothing that can escape the event horizon of the black hole, since light itself cannot. Then, how does gravitons or gravitational waves itself come out of the black hole to affect its surroundings?
7) 6)Any mass can have a finite amount of energy in it. Also, any mass attracts every other mass by gravitational force. Now, when work is done by this force, energy is lost e.g. work done by a star in a solar system .So, a time must come when a body runs out of energy, but this doesn’t happen. Why?
8) 7) Does neutron have an anti-particle? If no, why? If yes, then what is its charge?
9) 8) Nothing can cross the speed of light is what Einstein's Special and general relativity states.It's known that just after The Big Bang the universe expanded at a speed greater than that of light. Where does the fallacy lie?
9
1. The rest mass of a photon is zero.
ReplyDeleteActually, here the concept of gravitation has no meaning. Here what you need to talk about is the escape velocity of a black hole. As you know, black hole is the ultimate stage of a star, rather you can say it is the remnant left after the death of a star. Black hole is the condition when the density of the star increases so much that it tends to infinity. You can say one teaspoon of a black hole would weigh about 1 ton. Now, what is escape velocity. Escape velocity is the velocity required by an object to leave the field(here, its gravitational field of the black hole). As you know escape velocity is inversely proportional to the radius of the body therefore for a black hole, as radius tends to zero so escape velocity tends to infinity (greater than the speed of light). Hence you can say that nothing present in the field of a black hole can escape it. In the equation, please note that the escape velocity has nothing to do with the mass of light. Hence, it would be correct to say that light also can't escape out of a black hole.
Note: It would be wrong to say that the gravitational pull of the black hole attracts light. The correct statement would be light, if enters the field of black hole, can't escape out of it.
Abhilash Chatterjee
Yes I second your point. But my question is, how do gravitons or gravitational field escape the event horizon of a black hole if photons/electromagnetic waves can't?
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