String Dualities and Geometry
de
dimanche 14 janvier 2018 (18:00)
à
vendredi 19 janvier 2018 (17:00)
lundi 8 janvier 2018
mardi 9 janvier 2018
mercredi 10 janvier 2018
jeudi 11 janvier 2018
vendredi 12 janvier 2018
samedi 13 janvier 2018
dimanche 14 janvier 2018
18:00
Reception and Registration
Reception and Registration
18:00 - 20:00
lundi 15 janvier 2018
09:30
Supersymmetric backgrounds and moduli in generalised geometry
-
Daniel Waldram
Supersymmetric backgrounds and moduli in generalised geometry
Daniel Waldram
09:30 - 10:10
Room: Aula de conferencias
10:10
A generalised approach to consistent truncations
-
Michela Petrini
A generalised approach to consistent truncations
Michela Petrini
10:10 - 10:50
Room: Aula de conferencias
We discuss how to formulate consistent truncations with different amount of supersymmetry in the context of generalised geometry and we give some examples.
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula de conferencias
11:20
How to uplift gauged [maximal] supergravities
-
Gianluca Inverso
How to uplift gauged [maximal] supergravities
Gianluca Inverso
11:20 - 12:00
Room: Aula de conferencias
I will give the general procedure to construct uplifts of gauged supergravities based on generalised parallelisable spaces (i.e. on generalised Scherk-Schwarz reductions). The existence of uplifts, solutions to the section condition as well as the explicit expressions of the parallelisations are algebraically derived from the embedding tensor of the gauged supergravity. Known examples will be rederived and new applications discussed.
12:00
Lunch
Lunch
12:00 - 14:30
Room: Aula de conferencias
14:30
Brane Wess-Zumino terms in String Theory
-
Eric Bergshoeff
Brane Wess-Zumino terms in String Theory
Eric Bergshoeff
14:30 - 15:10
Room: Aula de conferencias
I will present some old and new results on duality-covariant brane Wess-Zumino terms describing their coupling to supergravity background fields. In particular, I will show how this leads to a classification of branes satisfying interesting wrapping rules and to the introduction of so-called exotic branes.
15:10
Flatfolds
-
Dall'agata Gianguido
Flatfolds
Dall'agata Gianguido
15:10 - 15:50
Room: Aula de conferencias
15:50
Coffee Break
Coffee Break
15:50 - 16:20
Room: Aula de conferencias
16:20
Classification of doubled-yet-gauged spacetime
-
Jeong-Hyuck Park
Classification of doubled-yet-gauged spacetime
Jeong-Hyuck Park
16:20 - 17:00
Room: Aula de conferencias
A classification of the generalized metric in DFT is presented. Analyses on the particle as well as the string dynamics upon the backgrounds are discussed through doubled-yet-gauged sigma models. DFT describes not only Riemannian gravity but also Newton-Cartan gravity, Carroll geometry or chiral string theories, etc. The talk is based on 1707.03713 with Kevin Morand.
mardi 16 janvier 2018
09:30
Algebraic structures in double and exceptional field theory
-
Olaf Hohm
Algebraic structures in double and exceptional field theory
Olaf Hohm
09:30 - 10:10
Room: Aula de conferencias
10:10
L_infinity algebras and CFT
-
Ralph Blumenhagen
L_infinity algebras and CFT
Ralph Blumenhagen
10:10 - 10:50
Room: Aula de conferencias
It is shown that the closure of the infinitesimal symmetry transformations underlying classical (global) W-algebras give rise to L$_\infty$ algebras with in general field dependent gauge parameters. We develop the general formalism for this correspondence and apply it explicitly to the classical W3-algebra. The generalization to the quantum case is discussed as well.
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula de conferencias
11:20
Branes in EFT/DFT, exotic and otherwise
-
David Berman
Branes in EFT/DFT, exotic and otherwise
David Berman
11:20 - 12:00
Room: Aula de conferencias
12:00
Lunch
Lunch
12:00 - 14:30
Room: Aula de conferencias
14:30
On higher spin representations of K(E10)
-
Hermann Nicolai
On higher spin representations of K(E10)
Hermann Nicolai
14:30 - 15:10
Room: Aula de conferencias
15:10
Affine generalized diffeomorphisms
-
Guillaume Bossard
Affine generalized diffeomorphisms
Guillaume Bossard
15:10 - 15:50
Room: Aula de conferencias
15:50
Coffee Break
Coffee Break
15:50 - 16:20
Room: Aula de conferencias
16:20
Extended Geometries
-
Martin Cederwall
Extended Geometries
Martin Cederwall
16:20 - 17:00
Room: Aula de conferencias
We present a unified and completely general formulation of extended geometry, characterised by a Kac-Moody algebra and a highest weight coordinate module. Generalised diffeomorphisms are constructed, as well as solutions to the section constraint. Generically, additional ("ancillary") gauge transformations are present, and we give a concrete criterion determining when they appear. A universal form of the (pseudo-)action determines the dynamics in all cases without ancillary transformations, and also for a restricted set of cases based on the adjoint representation of a finite-dimensional simple Lie group. Our construction reproduces (the internal sector of) all previously considered cases of double and exceptional field theories.
17:30
Beer @Kunstmann
Beer @Kunstmann
17:30 - 20:00
mercredi 17 janvier 2018
09:30
Non-Abelian T-duality in AdS/CFT: the CFT side
-
Yolanda Lozano
Non-Abelian T-duality in AdS/CFT: the CFT side
Yolanda Lozano
09:30 - 10:10
Room: Aula de conferencias
We will discuss recent progress in the understanding of the CFT realization of non-Abelian T-duality when acting on AdS spaces with known CFT duals.
10:10
Generalised T-dualities and Integrable Deformations
-
Daniel Thompson
Generalised T-dualities and Integrable Deformations
Daniel Thompson
10:10 - 10:50
Room: Aula de conferencias
In this talk I will present an overview of classes of integrable deformations to sigma models known as lambda and eta deformations. I explain the interesting interplay of the these models with generalisations of T-duality involving both non-Abelian isometries and Poisson-Lie symmetry. I will report on recent work considering the quantum aspects of multi-parameter integrable deformations. For the lambda-XXZ model I shall explain how we can implement its quantisation on a light cone lattice as the Heisenberg XXZ spin chain in the gapless regime. For the eta theory with a WZ term we will discuss aspects of its renormalisation and show how it exhibits an interesting self duality under Poisson-Lie symmetries.
10:50
Coffee Break
Coffee Break
10:50 - 11:10
Room: Aula de conferencias
11:10
Poisson-Lie T-duality in Double Field Theory
-
Falk Hassler
Poisson-Lie T-duality in Double Field Theory
Falk Hassler
11:10 - 11:50
Room: Aula de conferencias
11:50
Hidden isometry of “T-duality without isometry”
-
Ctirad Klimcik
Hidden isometry of “T-duality without isometry”
Ctirad Klimcik
11:50 - 12:30
Room: Aula de conferencias
We study the T-dualisability criteria of Chatzistavrakidis, Deser and Jonke who recently used Lie algebroid gauge theories to obtain sigma models exhibiting a ``T-duality without isometry''. We point out that those T-dualisability criteria depend on the choice of the algebroid framing. We then show that there always exists an isometric framing for which the Lie algebroid gauging boils down to the standard Yang-Mills gauging recovering thus the traditional isometric non-Abelian T-duality in disguise.
12:30
Lunch and Free afternoon / Excursion
Lunch and Free afternoon / Excursion
12:30 - 17:30
Room: Aula de conferencias
jeudi 18 janvier 2018
09:30
The structure of a DFT algebroid
-
Athanasios Chatzistavrakidis
The structure of a DFT algebroid
Athanasios Chatzistavrakidis
09:30 - 10:10
Room: Aula de conferencias
In this talk we will discuss some geometric aspects of double field theory. We will argue that the geometric structure of DFT lies in between two pre-Courant algebroids, related to one of them by a projection map and to the other by solving the strong constraint. The structure is not itself a (pre-)Courant algebroid. The proposed picture provides a geometric origin for DFT and its strong constraint, and at the same time it allows for a precise geometric definition of a DFT algebroid.
10:10
Membrane sigma models and DFT
-
Larisa Jonke
Membrane sigma models and DFT
Larisa Jonke
10:10 - 10:50
Room: Aula de conferencias
Based on the one-to-one correspondence between Courant algebroids and membrane sigma models, we propose a membrane sigma model for double field theory. We discuss the relation of the sigma model to the flux formulation of DFT and show that its gauge symmetries reproduce the structure of a DFT algebroid. In addition, we present some examples that clarify its relation to non-geometric string backgrounds. Finally, we discuss the possibility of relaxing the strong constraint of DFT by allowing for a dynamical fiber metric.
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula de conferencias
11:20
Non-geometric fluxes and non-associativity in M-theory
-
Dieter Lust
Non-geometric fluxes and non-associativity in M-theory
Dieter Lust
11:20 - 12:00
Room: Aula de conferencias
In this talk we discuss non-geometric fluxes in M-theory using exceptional field theory. We will point out that there is a new set of non-geometric fluxes in the R-R sector in the perturbative limit. We show that there are missing momenta conditions, induced by the fluxes. Finally the non-geometric fluxes together with the missing momenta lead to a non-associative phase space, which is related to the non-associative algebra of the octonions.
12:00
Lunch
Lunch
12:00 - 14:30
Room: Aula de conferencias
14:30
Locally non-geometric fluxes in M-theory and missing momenta
-
Emanuel Malek
Locally non-geometric fluxes in M-theory and missing momenta
Emanuel Malek
14:30 - 14:50
Room: Aula de conferencias
I will discuss locally non-geometric backgrounds in M-theory. Using duality chains based on twisted tori, I will show that such backgrounds typically have certain missing momentum modes.
14:50
The exceptional sigma model
-
Chris Blair
The exceptional sigma model
Chris Blair
14:50 - 15:10
Room: Aula de conferencias
I will explain the exceptional sigma model, which describes how a string couples to an exceptional field theory background.
15:10
Progress in massive IIA holography
-
Adolfo Guarino
Progress in massive IIA holography
Adolfo Guarino
15:10 - 15:30
Room: Aula de conferencias
15:30
Universal instabilities of non-susy AdS vacua
-
Giuseppe Dibitetto
Universal instabilities of non-susy AdS vacua
Giuseppe Dibitetto
15:30 - 15:50
Room: Aula de conferencias
15:50
Coffee Break
Coffee Break
15:50 - 16:20
Room: Aula de conferencias
16:20
T-duality transformations along angular directions for the NS5-brane
-
Erik Plauschinn
T-duality transformations along angular directions for the NS5-brane
Erik Plauschinn
16:20 - 16:40
Room: Aula de conferencias
I review the uncompactified NS5-brane solution and define in addition to the H-flux a geometric charge for this background. Under T-duality these charge are interchanged, and supersymmetry will be partially broken. These results are compared to the compactified-and-smeared solution, which shows very different behaviour.
16:40
Generalized Kinematics and Dynamics for Double Field Theory
-
Felix Rudolph
Generalized Kinematics and Dynamics for Double Field Theory
Felix Rudolph
16:40 - 17:00
Room: Aula de conferencias
Double Field Theory can be formulated on a 2d-dimensional para-Hermitian manifold ($P,\eta,\omega$) by supplementing the $O(d,d)$ metric $\eta$ with an almost symplectic two-form $\omega$. Together $\eta$ and $\omega$ provide a bi-Lagrangian splitting of the tangent bundle TP into two Lagrangian subspaces. I will sketch how to construct a canonical connection and a corresponding generalized Lie derivative for the Leibniz algebroid on TP. Under certain integrability conditions the symmetry algebra closes for general $\eta$ and $\omega$, even when they are not flat and constant. This provides a generalization of the kinematical structure of DFT. By including the generalized metric $H$ into the setup - which thus becomes para-quaternionic - we can construct a connection compatible with all three structures ($\eta, \omega, H$) and thus can also generalize the dynamics. The precise relation between DFT and generalized geometry is also discussed.
17:00
Supersymmetric brane field theories and non-linear instantons on curved backgrounds
-
Hagen Triendl
Supersymmetric brane field theories and non-linear instantons on curved backgrounds
Hagen Triendl
17:00 - 17:20
Room: Aula de conferencias
In recent years supersymmetric field theories have been realized on large classes of curved backgrounds, by coupling them to off-shell supergravity backgrounds. I will describe how these field theories are realized in string theory on D-branes in flux backgrounds, and how the auxiliary fields of off-shell supergravity can be matched with the various fluxes of string theory. Finally I will discuss how linear and non-linear supersymmetries and their instantons can be described by using an R-symmetry covariant description.
17:20
Moduli mass hierarchy in non-geometric flux compactifications
-
Oscar Loaiza-Brito
Moduli mass hierarchy in non-geometric flux compactifications
Oscar Loaiza-Brito
17:20 - 17:40
Room: Aula de conferencias
We study some conditions on which there is a hierarchy on the moduli masses on a type IIB tori compactification in the presence of non-geometrical fluxes.
17:40
Let’s talk about winding modes again
-
Martin Mayo
Let’s talk about winding modes again
Martin Mayo
17:40 - 18:00
Room: Aula de conferencias
DFT was, at the beginning, created to incorporate the windings modes and in this way get stringy features in a field theory. But then section condition appeared and all the motivation was lost. In this talk I will speak about new ways of incorporating windings and going beyond the section condition, taking advantage of the enhancement property of string theory.
18:00
A DFT O(d,d,Z) invariant action including (some) winding modes
-
Yago Cagnacci
A DFT O(d,d,Z) invariant action including (some) winding modes
Yago Cagnacci
18:00 - 18:20
Room: Aula de conferencias
18:20
Conference Dinner
Conference Dinner
18:20 - 22:30
Room: Aula de conferencias
vendredi 19 janvier 2018
09:30
Duality in Convex Optimization: Application to Minimal Area Surfaces
-
Barton Zwiebach
Duality in Convex Optimization: Application to Minimal Area Surfaces
Barton Zwiebach
09:30 - 10:10
Room: Aula de conferencias
We define convex programs and describe the construction of dual programs. After explaining the key results of this theory (max-flow min-cut, strong duality, complementary slackness, etc) we apply the methods to find unknown genus one minimal area surfaces.
10:10
Non-geometric Calabi-Yau backgrounds
-
Chris Hull
Non-geometric Calabi-Yau backgrounds
Chris Hull
10:10 - 10:50
Room: Aula de conferencias
10:50
Coffee Break
Coffee Break
10:50 - 11:20
Room: Aula de conferencias
11:20
TBA
-
Charles Strickland Constable
TBA
Charles Strickland Constable
11:20 - 12:00
Room: Aula de conferencias
12:00
Lunch
Lunch
12:00 - 14:30
Room: Aula de conferencias
14:30
AdS classifications
-
Alessandro Tomaseillo
AdS classifications
Alessandro Tomaseillo
14:30 - 15:10
Room: Aula de conferencias
I will review recent classification results about AdS$_d$ compactifications in various dimensions. While the efforts in $d>4$ were originally motivated by holography, several examples should be useful for flux compactifications, for example because of the simultaneous presence of back-reacted sources of different types. In AdS$_7$ we now have a one-line description of all possible solutions. In AdS$_5$ a large class is related to AdS$_7$ by compactification; among these, some interesting examples with ``punctures'' are starting to emerge. Finally, I will talk about classifying AdS$_4$ solutions with extended supersymmetry.
15:10
Supersymmetry and geometry of stringy corrections
-
Ruben Minasian
Supersymmetry and geometry of stringy corrections
Ruben Minasian
15:10 - 15:50
Room: Aula de conferencias
I’ll try to review why there are still open questions (that we should care about) concerning the structure of stringy corrections to low energy effective actions and if/how generalised geometry can help to answer these.
15:50
Coffee Break
Coffee Break
15:50 - 16:20
Room: Aula de conferencias
16:20
Is String Phenomenology an Oxymoron?
-
Fernando Quevedo
Is String Phenomenology an Oxymoron?
Fernando Quevedo
16:20 - 17:00
Room: Aula de conferencias