The Firewall Paradox: What is wrong with quantum gravity?

This research is a review of the firewall paradox recently encountered in physics. The book has an introduction about general relativity main results in quantum field theory in curved spacetimes (i.e. Unruh and Hawking radiations) and a section about quantum entanglement. The firewall paradox is explained in detail. Then 10 different approaches towards the solution of the paradox are listed. Appendices include the calculation of Bogoliubov coefficients entangled nature of vacuum and an analogue of Heisenberg''s uncertainty relation.