On **02/12/13**

On **09/12/13**

The first part will deal with an "intuitive' sketch of holography and its application. The second part will be a brief review of entanglement entropy and its properties with a briefer recap of the scheme Hamid presented in gory details in his talk. In the final part I shall discuss about the holographic proposal to compute entanglement entropy and if time permits, the justification of the same given by Maldacena in a recent paper.

On **13/01/14**

On **24/01/14**

**Abstract: **Last week we discussed the Dirac procedure of analyzing constraint Hamiltonian systems. This week we will work out the example of Three Dimensional gravity with a cosmological constant. We follow the Dirac procedure and show that the theory is pure gauge an does not propagate local degrees of freedom. Afterwards, we show how the presence of a boundary together with non-trivial boundary conditions generate an asymptotic symmetry algebra which we compute in the case of pure 3D gravity. We will also remark on the relation to Chern-Simons gauge theories.

On **10/02/14**

On **24/02/14**

On **10/03/14**

On **17/03/14**

On **07/04/14**

On **30/04/14**

**Speaker:** Sjoerd de Haan

**Title: **** **Vierbein formulation of general relativity

**Abstract: **The Einstein-Hilbert action of general relativity is a second order differential of the metric. An equivalent formulation describes general relativity in terms of two fields called the vierbein and the spin connection.There are several situations in which it can be an advantage to work with the vierbein and the spin connection instead of the metric:

1) Fermions can be coupled in a natural way to general relativity in the vierbein formalism.

2) The mass term of the de Rham-Gabadadze-Tolly model for massive gravity can be expressed in terms of vierbeins in a natural way.

3) General relativity in three dimensions can be expressed as Chern-Simons theory of the dreibein and the spin connection.

4) For many geometries, the Riemann tensor can be calculated from the vierbein more easily then from the metric.

The goal of this lecture is to explain the form of general relativity in the vierbein formulation. We start replacing the metric by the vierbein and the spin connection. In order to reformulate the Einstein-Hilbert action, all we have to do is to rewrite the Riemann curvature tensor in terms of these two fields. We end with an expression for the cosmological constant in terms of the vierbein.

On **12/05/14**

**Speaker:** Marco Scalisi

**Title:** An introduction to Inflation: lecture #1

**Abstract:** After a short review of the physics of the FRW space-times, we will presents the shortcomings of the standard big bang cosmological model. Then, we will introduce a simple and powerful way to solve such issues, namely the inflationary paradigm.

On **19/05/14**

**Speaker:** Marco Scalisi

**Title:** An introduction to Inflation: lecture #1

**Abstract:** We recap the main points of the first lecture and focus specifically on the two most famous shortcomings of the Standard Model of cosmology, namely the Flatness problem and the Horizon problem. We introduce the inflationary paradigm together with its dynamical implementation, the so-called “slow-roll” inflation, in terms of a scalar field. The latter will lead us naturally to a classification of inflationary models depending on the field range and to a discussion on the well-known Lyth bound.

On** 23/06/14**

**Speaker:** Souvik Banerjee

**Title :** Thermodynamics of AdS Black Holes (And gauge theory duals).

**Abstract :** I shall derive thermodynamics of AdS black holes from the action principle and discuss the phase transitions therein.

If time permits, I shall talk about some effective gauge theory models that capture those transitions and related physics at least near critical points.

*Person whom you have to contact (in case you are willing to give a talk)/ who will contact you (in case you are not so willing!)*