This work answers the basic questions of superconductivity in a question-and-answer format. We extend a basic hypothesis to various superconductors. This hypothesis is that superconductivity requires that the pairing gap locates around the Fermi level. On the basis of this hypothesis our calculations give the so-called three factor theory with which some key problems of the high temperature superconductivity are explained.
@article{arxiv.1006.5496,
title = {Ten questions and answers about superconductivity},
author = {Tian De Cao},
journal= {arXiv preprint arXiv:1006.5496},
year = {2012}
}