some intersting links

ARXIV.ORG
https://arxiv.org/pdf/physics/0701240.pdf
https://arxiv.org/pdf/1404.6483.pdf

WIKI
https://en.wikipedia.org/wiki/Second_quantization
https://en.wikipedia.org/wiki/Simply_connected_space
https://en.wikipedia.org/wiki/Convergence_problem **
https://en.wikipedia.org/wiki/Cosmological_constant_problem

http://www.askamathematician.com/2011/06/q-what-exactly-is-the-vacuum-catastrophe-and-what-effects-does-this-have-upon-our-understanding-of-the-universe/