About 14 billion years ago, the Big Bang was the beginning of our universe. What exactly exploded there, was there anything before this explosion, how hot was it immediately? What is quark-gluon plasma? What press can compress matter by a factor of quadrillion, what is the density of a neutron star, which is now being studied with the help of the Large Hadron Collider at CERN. And finally, why do we exist in nature at all?