Regular Seminar Rodolfo Russo (QMUL)

at:15:00
room A225 | abstract: The AdS/CFT duality maps supersymmetric heavy operators with conformal dimension of the order of the central charge to asymptotically AdS supergravity solutions. I'll show how by studying the quadratic fluctuations around such backgrounds it is possible to derive the 4-point correlators of two light and two heavy states in the supergravity approximation. I'll present some explicit examples in the AdS3 setup relevant for the duality with the D1-D5 CFT and discuss what we can learn in general about correlators among heavy pure states. |

Triangular Seminar Joan Simon (Edinburgh)

at:16:00
room A130 | abstract: The extremal limit of single R-charged AdS5 black holes in type IIB is known to be described by a system of N free fermions in a one dimensional harmonic oscillator potential. Since the quantum mechanical problem is solvable and its phase space formulation appears in the gravity dual (LLM geometries), it allows us to explore the relation between entanglement, quantum correlation design and connectivity in space in this set-up, both in a single and a two boundary situation. |

Triangular Seminar Amit Sever (CERN)

at:17:30
room A130 | abstract: We study non-planar corrections to gluon scattering amplitudes in N = 4 SYM theory. In this talk, we focus on the first correction. It is computed by the double trace amplitude and is suppressed by one power of 1/Nc with respect to the leading single trace contribution. We extend the duality between planar scattering amplitudes and null polygonal Wilson loops to the double trace amplitude. The new duality allows us to extend the notion of loop integrand beyond the planar limit and to determine it using recursion relation. It also allows us to apply the integrability pentagon approach to the first non-planar order. We shortly discuss higher orders in the 't Hooft 1/Nc expansion. |

Exceptional Seminar Daniele Musso (IGFAE)

at:13:00
room H503 | abstract: The spatially modulated self-organization of strongly-correlated electrons is central in describing the phenomenology of many condensed matter systems, such as the cuprates and the manganites. Holography can describe spontaneous formation of various kinds of density waves in a strongly-coupled media and provides toy-model effective field theories able to capture important phenomenological features, such as the low-temperature scaling of the conductivity. Appropriate UV completions of the holographic EFT can also describe the spontaneous generation of the spatial features themselves. |

Exceptional Seminar Amit Sever (Tel-Aviv University)

at:13:00
room S -2.23 | abstract: In the talk I'll consider theories of weakly interacting higher spin particles in flat spacetime. We will focus on the four-point scattering amplitude at high energies and imaginary scattering angles. Both, the leading asymptotic of the amplitude and the first sub-leading correction in this regime turn out to be universal. The leading asymptotic is equal to the corresponding limit of the Veneziano amplitude. We will compute the first sub-leading correction using a model of relativistic strings with massive endpoints and argue that it is unique using holography, the effective theory of long strings and bootstrap techniques. |