Seminář se koná v úterý ve 13:10 v posluchárně ÚTF MFF UK
v 10. patře katedrové budovy v Tróji, V Holešovičkách 2, Praha 8
The Unruh-DeWitt (UDW) detector was introduced originally to give an operational meaning to particle detection in curved spacetimes. This simple two level quantum system interacts with the quantum field through a monopole type coupling, possibly exciting it to the excited state in the process. As the vacuum state of the field depends on global features of the background spacetime, the transition probability of a detector may be able to pick up these features too. As a result, UDW can be better-than-classical-detectors. Specifically, we shall see that UDW detectors are able to detect the presence and rotation of a massive spherical shell enclosing them even though the spacetime inside the shell is Minkowskian. Moreover in the case of a cylindrical shell, both the interior and exterior spacetimes are locally flat, but there is a conical deficit present outside the shell. This can also be detected by detectors placed in the shell.
An exact solution of Einstein's equations will be described which represents an accelerating black hole with a NUT parameter. The solution was found by Chng, Mann and Stelea in 2006. A new convenient form of this metric will be presented, together with its algebraic, geometric and physical properties.
Jiří Bičák Oldřich Semerák