Triangle Seminars
Wednesday, 6 Nov 2013
Quantum black hole entropy and the holomorphic prepotential
📍 London
Sameer Murthy
(King's College)
Thursday, 7 Nov 2013
On Scale and Conformal Invariance in Four Dimensions
Anatoly Dymarsky
(DAMTP, Cambridge)
Abstract:
I will be discussing the relation between scale and conformal
symmetry in unitary Lorentz invariant QFTs in four dimensions.
I will be discussing the relation between scale and conformal
symmetry in unitary Lorentz invariant QFTs in four dimensions.
Posted by: IC
Twistor Strings for N=8 Supergravity
David Skinner
(Cambridge)
Abstract:
I'll explain a new way of looking at 4d supergravity –- as a theory of holomorphic maps
into Penrose's twistor space. Allowing twistor space to have N fermionic directions, the
theory is anomaly free when N=8. Via the Penrose transform, the vertex operators
correspond to an N=8 Einstein supergravity multiplet. Conformal symmetry is explicitly
broken by the presence of the infinity twistor in the BRST operator. I will show how to
compute the complete classical S-matrix from worldsheet correlation functions, and
interpret these amplitudes geometrically.
I'll explain a new way of looking at 4d supergravity –- as a theory of holomorphic maps
into Penrose's twistor space. Allowing twistor space to have N fermionic directions, the
theory is anomaly free when N=8. Via the Penrose transform, the vertex operators
correspond to an N=8 Einstein supergravity multiplet. Conformal symmetry is explicitly
broken by the presence of the infinity twistor in the BRST operator. I will show how to
compute the complete classical S-matrix from worldsheet correlation functions, and
interpret these amplitudes geometrically.
Posted by: QMW
Friday, 8 Nov 2013
All AdS_7 solutions of type II supergravity
Dario Rosa
(Milano Bicocca)
Abstract:
In M-theory, the only AdS_7 supersymmetric solutions are AdS_7 x S^4 and its orbifolds. We find and classify new supersymmetric solutions of the type AdS_7 x M_3 in type II supergravity. While in IIB none exist, in IIA with Romans mass (which does not lift to M-theory) there are many new ones. We use a pure spinor approach reminiscent of generalized complex geometry. Without the need for any Ansatz, the system determines uniquely the form of the metric and fluxes, up to solving a system of ODEs. Namely, the metric on M_3 is that of an S^2 fibered over an interval; this is consistent with the Sp(1) R-symmetry of the holographically dual (1,0) theory. By including D8 brane sources, one can numerically obtain regular solutions, where topologically M_3 = S^3.
In M-theory, the only AdS_7 supersymmetric solutions are AdS_7 x S^4 and its orbifolds. We find and classify new supersymmetric solutions of the type AdS_7 x M_3 in type II supergravity. While in IIB none exist, in IIA with Romans mass (which does not lift to M-theory) there are many new ones. We use a pure spinor approach reminiscent of generalized complex geometry. Without the need for any Ansatz, the system determines uniquely the form of the metric and fluxes, up to solving a system of ODEs. Namely, the metric on M_3 is that of an S^2 fibered over an interval; this is consistent with the Sp(1) R-symmetry of the holographically dual (1,0) theory. By including D8 brane sources, one can numerically obtain regular solutions, where topologically M_3 = S^3.
Posted by: IC