why the charge is conserved? why the charge of electron and proton not changes? why it is a constant?

Question

anonymous · Answer

1]charge conservation is the principle that electric charge can neither be created nor destroyed. The quantity of electric charge, the amount of positive charge minus the amount of negative charge in the universe, is always conserved.
Gauge invariance is a very important, well established property of the electromagnetic field and has many testable consequences. The theoretical justification for charge conservation is greatly strengthened by being linked to this symmetry. For example, local gauge invariance also requires that the photon be massless, so the good experimental evidence that the photon has zero mass is also strong evidence that charge is conserved.

anonymous · Answer

according to classical physics charge remains conserved, but according to Modern Physics the protons and electrons are divisible, so an absolute answer might be no, Just after the big bang it took time for electrons to come into existence, so the question can be answered by asking another question, "What was the state after the big bang before electrons condensed", Conventionaly under normal circumstances charge is conserved simply because strong forces of unexplained quarks

anonymous · Answer

the term conservation of electric charges means that charges can neither be created nor destroyed in separation. In simple words, charges can be created or destroyed only in same and opposite pairs.

when two bodies are rubbed together then one gets negative and other gets positive charge. It is clear from the fact that charges are not produced due to rubbing of bodies; charges are transferred from one body to another by disturbing the electrical neutrality of the bodies.

Examples that show the conservation of charge are:
1.In all the processes charge number is same every time.
2.In the circumstances of pair generation, a gamma photon divides into an electron and a positron. Then also the total charge –e+e=0. That is the total charge present on a photon.