
Fifth Joint Seminar  November 4, 2010


Sezione INFN
Università di Torino
Via Pietro Giuria, 1
I10125 TORINO

Seminars will take place in Aula Franzinetti



11:30 

Team Meeting 

14:15 

Welcome address 

14:30 

L. Dixon, «Scattering Amplitudes in Maximal Supersymmetry and for Backgrounds to Supersymmetry at the LHC»
Onshell scattering amplitudes have a multitude of applications. At a practical
level, they are needed to quantify Standard Model backgrounds to searches for
supersymmetry at the LHC. In maximally supersymmetric theories, they have
helped unveil new symmetries such as dual conformal invariance in N=4 superYangMills
theory, and the remarkably good ultraviolet behavior of N=8 supergravity. In many cases,
the most efficient way to compute amplitudes is using "onshell" methods,
which reconstruct (multi)loop amplitudes from lowerpoint and lowerleg
amplitudes using unitarity and factorization properties. I will present an
overview of these techniques and highlight some recent applications ranging
from phenomenology to supergravity.


15:30 

E. Sokatchev, «Scattering amplitudes: Symmetries and dualities»
We discuss different aspects of scattering amplitudes in maximally supersymmetric YangMills theory.
We review their hidden dynamical symmetries and the ways they can restrict the form of the amplitudes,
possibly leading to the full integrability of the theory. We also discuss the duality between amplitudes and
lightlike Wilson loops, as well as the recently discovered new duality with superconformal correlation
functions of local BPS operators in the singular lightcone limit.


16:30 

Coffee break 

17:00 

A. Tomasiello, «Phases of massive IIA string theory»
The socalled "massive" version of IIA string theory is characterized by a nonvanishing RamondRamond flux F_0
(the flux with no indices). This builtin mass parameter helps in several applications; for example, in producing
compactifications without massless scalars (in other words, in "stabilizing the moduli").
We review in this talk recent progress in understanding this theory. A crucial point is the quantization of the mass parameter.
This manifests itself in holographic duals as the quantization of a certain ChernSimons level. This can then be used to argue
that massive IIA classical solutions can never get strongly coupled. In particular, the massive theory doesn't generate an
"Mtheory" eleventh dimension, unlike its massless counterpart; this answers a longstanding question.


18:00 

End of the Meeting 

20:30 

Social dinner 




