E.g. if a photon is emitted by a positive charge towards a negative charge, shouldn't the negative charge move away from the positive charge to conserve momentum? I've heard that force carriers should simply be thought of as "messenger" particles, but that sounds like hand-waving to me.
2007-01-24 12:20:21 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Physics
In quantum electrodynamics, photons as gauge bosons (read "messenger particles") for the EM force are virtual photons, which "carry" quantum attributes such as momentum, which has nothing to do with its own "direction of travel". So, for example, if a photon leaves a charge particle that has a momentum of, say, 10 o'clock direction, and this virtual photon interacts with another charged particle that's in the, say, 2 o'clock direction from the first, the direction of momentum which was in the 10 o'clock direction is transferred to the other particle, so that the next effect is as if the two charged particles had struck together, without any need for any gauge bosons. I know that sounds absolutely tommyrot to you, and I can't blame you if you think this is all made-up hand-waving stuff, the fact is, when the extraordinarily complicated quantum field computations are worked out (via Feynman diagrams), it yields resutls of an extraordinarily high degree of precision, matching experimental measurements better than just about anything else in science. So, now you understand why people speak of quantum WIERDNESS? Enjoy.
2007-01-24 12:37:11 · answer #1 · answered by Scythian1950 7 · 1⤊ 1⤋
If there is any answer you should listen to its this one. Before the big bang, all the matter was packed into a space about as big as a baseball. In the object, the four fundamental forces were very very briefly stable. When they left equilibrium, the big bang happened. Those forces were: Strong Nuclear, Weak Nuclear, Electro-magnetism, and Gravity. Gravity was and is the weakest. The repulsive force from the SN (repelling protons to be precise) was many times stronger than gravity. The super dense ball basically flew apart, and the expansion was aided by the destruction of 99.99% of all matter by the collision of matter and antimatter (thank God there was a little bit more matter than antimatter or we wouldn't be here) The expansion of the "fabric of the universe" is related to time and gravity and has little to do with the BB.
2016-05-24 05:53:35 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Time reversed repulsive forces. At least thats my professional guess...
2007-01-24 12:27:16 · answer #3 · answered by Link 5 · 0⤊ 0⤋