Thanks a lot! Happy holiday to you as well!

Concerning your suggestions in the other comment, I was not considering writing about black holes in a close future, even if I have attended a few interesting seminars on this topic recently. I am in any case adding them to the list of topics, but I cannot tell you when this will be programmed. This is related to the outcome of an intense debate between me and myself ;)

For virtual particles, can you tell me exactly what you have in mind. Is it related to virtual particles in quantum field theory, as for instance when a given initial state comprising a particle-antiparticle pair annihilates into a virtual photon to give rise, for example, to a final state comprising a muon-antimuon pair?