## List of speakers

- Jose J. Fernández-Melgarejo (UM-YITP Kyoto University)
- Álvaro García Navarro (UM)
- Julio Guerrero (UM-Universidad Jaén)*
- Miguel Ángel Javaloyes (UM)
- Óscar Lasso (IFT/UAM-CSIC)
- Alessio Marrani ("Enrico Fermi" Center, Italy)
- Iván Martínez-Soler (IFT/UAM-CSIC)
- Cynthia Menchón (IFIC/Universidad Valencia-CSIC)
- Javier Molina-Vilaplana (UPCT)
- Tomás Ortín (IFT/UAM-CSIC)*
- Alejandro Ruipérez (IFT/UAM-CSIC)
- Néstor Sánchez (UM)
- Emilio Torrente-Luján (UM)

## Program (including slides)

### January, 19th

- 09:15 - 09:30 - Torrente-Luján: Supergravity in Murcia
- 09:30 - 10:00 - Javaloyes: An overview about Finsler spacetimes and Penrose's Singularity Theorem
- 10:00 - 10:30 - Molina-Vilaplana: Entanglement Renormalization and Two Dimensional String Theory
- 10:30 - 11:00 - Lasso: RG-2 flow, Mass and Entropy

- 11:00 - 11:30 - Coffee break

- 11:30 - 12:00 - Marrani: A Mystery of Black Hole Entropy
- 12:00 - 12:30 - Ruipérez: Non-Abelian microstate geometries
- 12:30 - 12:45 - García Navarro: Beyond Einstein: Einstein-Maxwell and Brans Dicke
- 12:45 - 13:15 - Torrente-Luján: Non-Abelian Hydrodynamics: The dimensional reduction and embedding tensor approaches

- 13:15 - 15:00 - Lunch

- 15:00 - 15:30 - Sánchez: Characterization of Galactic star clusters
- 15:30 - 16:00 - Martínez-Soler: Updated fit to three neutrino mixing: exploring the accelerator-reactor complementarity

- 16:00 - 16:15 - Coffee break

- 16:15 - 16:45 - Menchón: Wormholes in Born-Infeld gravity coupled to an anisotropic fluid.
- 16:45 - 17:15 - Fernández-Melgarejo: The Odd story of \alpha'-corrections

## Abstracts

#### Fernández-Melgarejo: The Odd story of \alpha' corrections

Double Field Theory (DFT) is a T-duality symmetric
formulation of 10D supergravity theories. Being T-duality a
perturbative duality, one can naturally ask whether such a similar
O(D,D) covariantisation also occurs in the \alpha'-corrected
supergravity action. In this talk we will review the higher-derivative
extension of DFT which accommodates the first order corrections of
heterotic and bosonic strings in a unified framework. As an
application of this formalism, we will explain how to compute
higher-derivative corrections to gauged supergravities through
generalised Scherk-Schwarz compactifications of the \alpha'-corrected
DFT. The final and novel result will be the full alpha'-corrected
action of half-maximal gauged supergravities. Based on [arXiv:1709.02388 [hep-th]].

#### García-Navarro: Beyond Einstein: Einstein-Maxwell and Brans Dicke

In this talk we will review the main aspects of General Relativity and
the importance of having objects that transform covariantly under
general coordinate transformations. We will study some black-hole type
solutions of Einstein and Einstein-Maxwell theories, as Schwarzschild
and Reissner-Nordstrom. Finally, we will introduce the Brans-Dicke
theory, which is an example of a scalar-tensor gravitational theory.
Here, the gravitational interaction is mediated by a scalar field as
well as the tensor field of General Relativity.

#### Javaloyes: An overview about Finsler spacetimes and Penrose's Singularity Theorem

Finsler Geometry comes into play in the presence of anisotropy, which means that locally not all the directions are indistinguishable. The lack of anisotropy of the universe has been recently conjectured in the frame of the Extended Standard Model, which motivates the study of Finsler spacetimes. We will first discuss the different definitions of Finsler spacetimes and how they have been used throughout the years. Then we will show how it is possible to generalize Penrose’s Singularity Theorem to a very general class of Finsler spacetimes.

#### Lasso-Andino: RG-2 flow, Mass and Entropy

Geometric flows are used in some branches of pure mathematics. Calculating the
evolution of a Riemannian metric and exploiting the monotonicity under the flow of some
appropriately constructed geometric quantities mathematicians are able to find bounds
and uniqueness results. One of the spectacular result is the proof of the Thurston geometrization
conjecture, with the help of the Ricci flow. The flows have also been used in the context
of mathematical physics, the riemannian Penrose inequality is a prominent example were
the inverse mean curvature flow was employed. Those techniques are very powerful and
can be used for understanding deep aspects of any geometric theory. I will show how to
use the RG-2 flow for determining monotonicity and bounds for geometrical quantities such
as the area and the Hawking mass. This RG-2 flow is the two loop approximation for the
renormalization group flow of the quantized nonlinear sigma model. I will also discuss
the relationship between differentflows and some applications. Finally I will talk about
new approaches to open problems.

#### Marrani: A Mystery of Black Hole Entropy

Freudenthal duality can be defined as an anti-involutive, non-linear map acting on symplectic spaces. After a general introduction on some aspects of extended (super)gravity theories in four dimensions and the structure of their U-orbits, I will consider their U-duality Lie groups "of type E7", and the corresponding notion of Freudenthal duality. I will elucidate and comment on the relation between the Hessian of the black hole entropy and the pseudo-Riemannian, rigid, para-special Kaehler metric of the pre-homogeneous vector spaces associated to the U-orbits. I will conclude with recent developments, including the extension to Abelian gaugings of supergravity (also in presence of hypermultiplets).

#### Martínez-Soler: Updated fit to three neutrino mixing: exploring the accelerator-reactor
complementarity

We perform a combined fit to global neutrino oscillation data available as of fall 2016 in
the scenario of three-neutrino oscillations and present updated allowed ranges of the six oscillation
parameters. We discuss the differences arising between the consistent combination of the data
samples from accelerator and reactor experiments compared to partial combinations. We quantify
the confidence in the determination of the less precisely known parameters θ2323, δCPCP, and the
neutrino mass ordering by performing a Monte Carlo study of the long baseline accelerator and
reactor data. We find that the sensitivity to the mass ordering and the θ2323 octant is below 1σ.
Maximal θ2323 mixing is allowed at slightly more than 90% CL. The best fit for the CP violating
phase is around 270°, CP conservation is allowed at slightly above 1σ, and values of δCPCP ≃ 90°
are disfavored at around 99% CL for normal ordering and higher CL for inverted ordering.

#### Menchón: Wormholes in Born-Infeld gravity coupled to an anisotropic fluid

We study Born-Infled gravity coupled to an anisotropic fluid in a static, spherically symmetric background. The free function characterizing the fluid is selected on the following grounds: i) recovery of the Reissner-Nordström solution of GR at large distances, ii) fulfillment of classical energy conditions and iii) inclusion of models of nonlinear electrodynamics as particular examples. Four branches of solutions are obtained, depending on the signs of two parameters on the gravity and matter sectors. We discuss the modifications on the innermost region of the corresponding solutions on one of branch, which provides a plethora of configurations, including wormholes. The regular character of these configurations is discussed according to the completeness of geodesics and the behavior of curvature scalars.

#### Molina-Vilaplana: Entanglement Renormalization and Two Dimensional String Theory

In this talk, based on arXiv:1510.09020, the entanglement renormalization flow of a (1+1) free boson is formulated as a path integral over some auxiliary scalar fields. The resulting effective theory for these fields amounts to the dilaton term of non-critical string theory in two spacetime dimensions. A connection between the scalar fields in the two theories is provided, allowing to acquire novel insights into how a theory of gravity emerges from the entanglement structure of another one without gravity.

#### Ruipérez: Non-Abelian microstate geometries

Microstate geometries are smooth horizonless solutions of supergravity theories, which
are claimed to represent the classical description of the microstates of a black hole. So far, no
systematic procedure to construct these type of solutions was known. I will talk about the results
of a recent paper (arXiv:1709.03985) in which we argue that the problem of constructing
explicit solutions can be boiled down to the evaluation of an algebraic constraint, allowing us to
design a systematic procedure to generate these solutions.

#### Sánchez: Characterization of Galactic star clusters

Star clusters have long been recognized as very useful
tools in many areas of astronomy. A precise knowledge
of cluster properties such as distance, age, metallicity
or reddening is necessary in order to be able to draw
reliable conclusions on, for instance, the rotation or
the star formation history of our Galaxy. I will explain
the main current problems when inferring cluster properties
and, in particular, when estimating a particularly valuable
parameter: cluster radius. I will discuss some previous
interesting results and a novel method we are proposing
in order to calculate the radius of an open cluster in
an objective way from the proper motion of its stars.

#### Torrente-Luján: Non-Abelian Hydrodynamics: The dimensional reduction and embedding tensor approaches

Since Cho&Freund (1975) we know that the diffeormorphism group in $D=d+n$ dimensions contains d-dimensional diffeormosphisms plus n-Non-Abelian gauge transformations. This is the basis of the Scherk-Schwarz mechanism.

We present a progress report of some ongoing research about new approaches to the study of non-Abelian plasmas.

The new approach is two fold, in one case we use the dimensional reduction on a group manifold of a D-fluid neutral fluid to get a non-Abelian system at lower dimensions. In the other complementary case we study, using the embedding tensor technique, borrowed from supergravity gauged theories, all possible non-abelian deformations of a fluid system with a given field content.

The work to be presented is made in collaboration with
JJ. Fernandez-Melgarejo and A. Ruiperez Vicente. It is the basis of two publications to appear, it is also related to arXiv:1605.06080.

## Banquet

TBA

### Organisation

- Jose J. Fernández-Melgarejo (Universidad de Murcia - YITP, Kyoto University)
- Emilio Torrente-Luján (Universidad de Murcia)

### Sponsorship

- FISPAC Research Group: Física de Partículas, Astrofísica y Cosmología
- Universidad de Murcia
- Fundación Séneca, Agencia de Ciencia y Tecnología