| Details: |
In the first part of my talk I will discuss the variational
principle for general relativity and some associated subtle facts not
shared by other interactions present in the nature. In particular, I
will try to arrive at the correct action principle for general
relativity in presence of null boundaries. Possible generalization to
Lovelock theories will also be presented.
In the second part of my talk, I will discuss the thermodynamics of
null surfaces. In particular, I will show that three different
projections of gravitational momentum related to an arbitrary null
surface in the space time leads to three different equations, all of
which have thermodynamic interpretations. Finally, I will also discuss
about the recent works that I am involved in, as well as other works
that I am pursuing in various other directions. |