Friday, Oct 09, 2015
10h00 Cours de physique théorique
Cours de physique théorique
Salle Claude Itzykson, Bât. 774 Orme des Merisiers
Sheer ElShowk and Miguel Paulos
Monday, Oct 12, 2015
11h00 Séminaire de physique mathématique
Séminaire de physique mathématique
Salle Claude Itzykson, Bât. 774 Orme des Merisiers
Semyon Klevstov
Tuesday, Oct 13, 2015
11h00 Séminaire général de l'IPhT
Séminaire général de l'IPhT
Salle Claude Itzykson, Bât. 774 Orme des Merisiers
Tomohiro SASAMOTO
Thursday, Oct 15, 2015
14h15 Groupe de travail
Groupe de travail
Salle Claude Itzykson, Bât. 774 Orme des Merisiers
JeanMarc Luck
The research performed at the IPhT aims at better understanding the laws which govern our universe and its organisation. It encompasses most of the great subjects of modern theoretical physics:
The IPhT comprises about fifty permanent physicists (2/3 CEA, 1/3 CNRS), about thirty PhD students and postdocs, assisted by a support staff of about ten people. The IPhT also hosts permanently many short term visitors.
The conference "de Sitter and microstate lansdscapes in string theory" took place at IPhT from June 16 to 19, 2015. This workshop gathered 70 participants from around the world to discuss recent advances in understanding the landscapes of de Sitter spaces in string theory on one hand, and of black hole microstate geometries on the other. Both landscapes have experienced quite intense recent remodeling: on the black hole side this was driven by “fuzzball/firewall” informationtheorybased arguments that black hole solutions are only thermodynamic approximations that stop describing the physics at the scale of the horizon, where they should be replaced by horizonless geometries dual to the black hole microstates, and on the cosmology side by the realization that antibranes, which are one of the key ingredients needed to obtain a landscape of de Sitter vacua, may give rise to instabilities. 

F. David, 20150703

A century ago Albert Einstein used his new theory of gravity – the general relativity  for evaluating the bending angle of rays of light under the gravitational pull from the Sun. Ludovic Planté, Pierre Vanhove and their colleagues have evaluated for the first time the quantum gravity correction to this bending angle. The computation is done in the framework of the lowenergy effective field theory, which allows evaluating large distance effects by keeping only low energy fields and couplings. This contribution is universal to any theory of quantum because since it is independent of (any unknown) highenergy degrees of freedom. The quantum correction depends on the spin of the deflected massless particle, in contrast to the classical contribution. Therefore it violates the equivalence principle but preserves the fundamental symmetries of the theory on which Einstein based his theory of general relativity. "Bending of Light in Quantum Gravity", N. E. J. BjerrumBohr, John F. Donoghue, Barry R. ... 

C. Pepin, 20150408

No one had checked before, but RNA, the nucleic acid involved in many cell functions including protein synthesis, appears to be the only « strand of life » not to have knots. Over the years, advances in structural biology have firmly established that both proteins and DNA, although subject to evolutionary selection, do not escape the statistical law whereby a sufficiently long and compacted molecular strand will inevitably be entangled. However, no one to date had looked into the case of RNA. Using the structural description provided for approximately 6,000 RNA chains entered in the Protein Data Bank, a team of researchers from the SISSA (Italy) and the IPhT has performed a thorough study of the presence of knots in these biopolymers. In order to detect knots, they used the following methods:


F. David, 20150408

Spin Vertex and 3 Point Function in AdS/CFT Correspondence