Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Concept

Théorie des twisteurs

Publications associées (17)

Where is M-theory in the space of scattering amplitudes?

João Miguel Augusto Penedones Fernandes, Andrea Guerrieri

We use the S-matrix bootstrap to carve out the space of unitary, analytic, crossing symmetric and supersymmetric graviton scattering amplitudes in nine, ten and eleven dimensions. We extend and improve the numerical methods of our previous work in ten dime ...

Springer Nature2023

Where Is String Theory in the Space of Scattering Amplitudes?

João Miguel Augusto Penedones Fernandes, Andrea Guerrieri

We use the S-matrix bootstrap to carve out the space of unitary, crossing symmetric and supersymmetric graviton scattering amplitudes in ten dimensions. We focus on the leading Wilson coefficient a controlling the leading correction to maximal supergravity ...

AMER PHYSICAL SOC2021

Towards bootstrapping RG flows: sine-Gordon in AdS

João Miguel Augusto Penedones Fernandes

The boundary correlation functions for a Quantum Field Theory (QFT) in an Anti-de Sitter (AdS) background can stay conformally covariant even if the bulk theory undergoes a renormalization group (RG) flow. Studying such correlation functions with the numer ...

Springer Nature2021

Linearized supergravity with a dynamical preferred frame

Sergey Sibiryakov

We study supersymmetric extension of the Einstein-aether gravitational model where local Lorentz invariance is broken down to the subgroup of spatial rotations by a vacuum expectation value of a timelike vector field called aether. Embedding aether into a ...

Springer Nature2021

Supergravity with broken Lorentz invariance: theory and phenomenological consequences

Sergey Sibiryakov

We construct and study supersymmetric extension of the Einstein-aether gravitational theory. Using superfield formalism we carry out unique linearized Lorentz violating supergravity action invariant under super-gauge transformations and obtain its bosonic ...

IOP PUBLISHING LTD2019

Procrustes Metrics on Covariance Operators and Optimal Transportation of Gaussian Processes

Victor Panaretos, Yoav Zemel, Valentina Masarotto

Covariance operators are fundamental in functional data analysis, providing the canonical means to analyse functional variation via the celebrated Karhunen-Loeve expansion. These operators may themselves be subject to variation, for instance in contexts wh ...

2019

Graviton scattering and a sum rule for the c anomaly in 4D CFT

Marc Gillioz

4D CFTs have a scale anomaly characterized by the coefficient c, which appears as the coefficient of logarithmic terms in momentum space correlation functions of the energy-momentum tensor. By studying the CFT contribution to 4-point graviton scattering am ...

Springer Nature2018

The Critical Shear Crack Theory for punching design: from a mechanical model to closed-form design expressions

Aurelio Muttoni, Miguel Fernández Ruiz

The Critical Shear Crack Theory (CSCT) is a consistent approach used for shear design of one- and two-way slabs failing in shear and punching shear respectively. The theory is based on a mechanical model allowing to determine the amount of shear force that ...

2016

On the global structure of deformed Yang-Mills theory and QCD(adj) on R-3 x S-1

Spatial compactification on R(3)xS(L)(1), at small S-1-size L often leads to a calculable vacuum structure, where various "topological molecules" are responsible for confinement and the realization of the center and discrete chiral symmetries. Within this ...

Springer Nature2015

Controlled stripes of ultrafine ferroelectric domains

Alexander Tagantsev, Nava Setter, Igor Stolichnov, Silviu Cosmin Sandu, Tomas Sluka, Ludwig Feigl, Petr Yudin, Konstantin Shapovalov, Mahamudu Mtebwa

In the pursuit of ferroic-based (nano) electronics, it is essential to minutely control domain patterns and domain switching. The ability to control domain width, orientation and position is a prerequisite for circuitry based on fine domains. Here, we deve ...

Nature Publishing Group2014

Metastable spontaneous breaking of N=2 supersymmetry

Claudio Scrucca, Paul Smyth

We show that contrary to the common lore it is possible to spontaneously break N = 2 supersymmetry even in simple theories without constant Fayet-Iliopoulos terms. We consider the most general N = 2 supersymmetric theory with one hypermultiplet and one vec ...

Elsevier Science Bv2013

On Certain Kahler Quotients of Quaternionic Kahler Manifolds

Paul Smyth

We prove that, given a certain isometric action of a two-dimensional Abelian group A on a quaternionic Kahler manifold M which preserves a submanifold N aS, M, the quotient M' = N/A has a natural Kahler structure. We verify that the assumptions on the grou ...

Springer-Verlag2013

Supersymmetric vacua in N=2 supergravity

Paul Smyth

We use the embedding tensor formalism to analyse maximally symmetric backgrounds of N = 2 gauged supergravities which have the full N = 2 supersymmetry. We state the condition for N = 2 vacua and discuss some of their general properties. We show that if th ...

Springer Nature2012

River Networks as Ecological Corridors: a Complex Systems Perspective for Integrating Hydrologic, Geomorphological and Ecologic Dynamics

Andrea Rinaldo, Enrico Bertuzzo

This paper synthesizes recent works at the interface of hydrology, geomorphology, and ecology under an integrated framework of analysis with an aim for a general theory. It addresses a wide range of related topics, including biodiversity of freshwater fish ...

American Geophysical Union2009

Constraints from F and D supersymmetry breaking in general supergravity theories

Claudio Scrucca

We study the conditions under which a generic supergravity model involving chiral and vector multiplets can admit vacua with spontaneously broken supersymmetry and realistic cosmological constant. We find that the existence of such viable vacua implies som ...

2008

Constraints on modular inflation in supergravity and string theory

Claudio Scrucca

We perform a general algebraic analysis on the possibility of realising slow-roll inflation in the moduli sector of string models. This problem turns out to be very closely related to the characterisation of models admitting metastable vacua with non-negat ...

Springer Nature2008

Stereographic Wavelet Frames on the Sphere

Pierre Vandergheynst, Iva Bogdanova Vandergheynst, Laurent Jacques

In this paper we exploit the Continuous Wavelet Transform (CWT) on the two dimensional sphere, introduced previously by two of us, to build associated Discrete Wavelet Frames. We first explore half-continuous frames, i.e., frames where the position remains ...

2005