Machine Learning Journal Club: 'Hierarchical Simulation-Based Inference of Supernova Physics'
2025-11-06 11:00 - 12:00 (Europe/Madrid) | Grey Room 2, Instituto de Física Teórica, Madrid, Madrid, 28037, Spain
Speaker: Alex Gagliano (IAIFI/MIT)
Venue&Time: 11:00 / Grey Room 2
Absrtact: Supernovae are powered by diverse physical mechanisms such as radioactive decay, circumstellar interaction, and magnetar spin-down, but distinguishing among them from light curves alone remains a major challenge. In this talk, I’ll present a hierarchical simulation-based inference framework that jointly infers both the dominant power source and the key physical parameters of supernovae. By training conditional neural density estimators end-to-end across multiple physical models, this approach yields calibrated posteriors even in regions of strong degeneracy. I’ll highlight the model’s performance on synthetic data and outline plans to fine-tune the model for population-level studies of diverse explosion physics.

DIFT Colloquium: 'String Theory and the Dark Sector'
2025-11-06 15:30 - 17:30 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Cumrun Vafa (Harvard)

Venue & Time: Aula Polivalente, Plaza Mayor UAM / 15:30
Abstract: The dark sector — comprising dark energy and dark matter — has remained a profound mystery for decades. In this talk, I will review this subject and show how string theory naturally leads to a predictive framework for a unified dark sector. I will also discuss how these string-theoretic predictions align with exciting recent cosmological observations from the DES and DESI collaborations.

Ciclo de Charlas IFT + Residencia: 'Física fundamental en clave cuántica'
2025-11-06 18:00 - 2025-11-15 21:00 | Residencia de Estudiantes, C. del Pinar, 21-23, Chamartín, Madrid, Madrid, 28006, Spain
Con motivo del Año Internacional de la Cuántica, el Instituto de Física Teórica (IFT, UAM-CSIC) celebra una nueva edición de su ya tradicional Ciclo de Conferencias de Física Fundamental en la Residencia de Estudiantes. A lo largo de cuatro jornadas, investigadoras e investigadores del IFT, junto a figuras internacionales invitadas, abordarán el papel central que juega la física cuántica en nuestra comprensión del universo. Desde la computación cuántica hasta la teoría de cuerdas, pasando por los aceleradores de partículas y las conexiones inesperadas entre la física y el arte, el ciclo ofrecerá al público general una panorámica actualizada de la investigación física más avanzada.
Fechas: 6, 7, 13 y 14 de noviembre de 2025
PROGRAMA
Jueves, 6 de noviembre
18:00 | Álvaro M. Alhambra (IFT UAM-CSIC): “Computación cuántica, perspectivas de futuro”
La computación cuántica se encuentra en un punto de inflexión: tras décadas de desarrollo teórico, los primeros dispositivos experimentales empiezan a mostrar su potencial. ¿Qué podemos esperar en los próximos años? ¿Qué problemas reales podría resolver un ordenador cuántico? En esta charla exploraremos las bases de esta nueva tecnología, los retos actuales y las perspectivas científicas y tecnológicas a medio y largo plazo.
19:30 | Mª Ángeles Pérez García (USAL): “Deconstruyendo una estrella de neutrones”
Deconstruyendo una estrella de neutrones es un viaje al corazón de uno de los objetos más extremos del universo. A partir de los restos de una supernova, estas estrellas concentran más masa que el Sol en un radio de apenas una docena de kilómetros. En este viaje buscamos “desarmarlas” conceptualmente: entender cómo la materia se comporta cuando la presión convierte los átomos en un mar de neutrones superfluidos. Combinaremos física cuántica, y gravedad para entender sus capas y procesos internos. La idea es explorar cómo estos fascinantes objetos pueden ayudarnos a descifrar los misterios del interior estelar y, en última instancia, los límites mismos de la materia.
Viernes, 7 de noviembre
18:00 | Cumrun Vafa (Harvard): “Puzzles para descifrar el universo”
Debajo de todas las complejas y formidables estructuras matemáticas que formulan las leyes físicas, descansan simples pero profundas verdades. Son por estas verdades sencillas, y no por los detalles técnicos complicados, por lo que se esfuerzan los científicos cuando tratan de desvelar las leyes de la naturaleza. Afortunadamente, estas ideas clave pueden ilustrarse a menudo con sencillos puzles matemáticos (rompecabezas, acertijos,…). En esta charla expondré varios ejemplos de estos sencillos puzles y mostraré cómo pueden arrojar luz sobre algunos de los conceptos más profundos de la física. Además, se pedirá a los asistentes que participen en la resolución de los puzzles durante la charla, que será muy interactiva. Está basada en mi libro “La Simplicidad del Universo” (“Puzzles to Unravel the Universe”, en la versión original), dirigido al público en general y que no requiere tener amplios conocimientos de matemáticas o física, sólo un mínimo de curiosidad.
Esta charla se desarrollará en inglés y contará con un equipo de traducción simultánea.
Jueves, 13 de noviembre
18:00 | Ángel M. Uranga (IFT UAM-CSIC): “1000 maneras cuánticas de destruir el universo”.
Vivimos en un universo que parece estable… pero ¿y si solo lo fuera por ahora? Las leyes cuánticas permiten escenarios tan exóticos como inquietantes: desde la desintegración del vacío debido a inestabilidades en el campo de Higgs, hasta procesos más profundos que podrían surgir de una teoría aún incompleta de la gravedad cuántica. En esta charla exploraremos algunos de estos mecanismos hipotéticos —pero físicamente plausibles— que podrían, en última instancia, provocar el colapso del universo tal y como lo conocemos.
19:30 | Ana Cueto (UAM): “El futuro de la cuántica en los grandes aceleradores”
¿Qué papel jugará la física cuántica en la próxima generación de aceleradores de partículas? Con instalaciones como el LHC y sus sucesores, las tecnologías que estudian la estructura de la materia entran en una nueva era. Esta charla analizará qué descubrimientos podríamos tener en el horizonte.
Viernes, 14 de noviembre
19:00 | Esperanza López (IFT UAM-CSIC): “Música y experiencias cuánticas”
La física cuántica ha transformado nuestra visión del mundo, y su belleza abstracta ha inspirado otras disciplinas, como la música. En esta charla singular, exploraremos los vínculos y paralelismos entre la experiencia estética y el asombro científico.
Con la colaboración de los siguientes artistas:
Miguel Álvarez-Fernández: Artista sonoro, compositor, musicólogo y ensayista de reconocido prestigio. Desde 2008 dirige y presenta el programa Ars Sonora en Radio Clásica.
Alvaro Pérez: Saxofonista y compositor. Reconocida figura del Jazz y la improvisación, con una extensa discografía. Ha tocado con varias orquestas, incluyendo la de RTVE como solista.
Roberto Jabonero: Violinista y productor musical. Ha formado parte de importantes agrupaciones de clásica y moderno del panorama español. Es director de la Escuela de Música de Tres Cantos.
Bruno Dozza: Autor de obras de cámara, sinfónicas y escénicas estrenadas en festivales y salas en Europa, Asia y Estados Unidos. Ha colaborado con destacados artistas internacionales.
Carlos de la Blanca: reconocido y joven pianista. Ha dado numerosos recitales en tanto en España como en el extranjero. Ha sido premiado en varios concursos nacionales e internacionales en España.

10th IBS/MultiDark WS: Dark Matter and Axions
2025-11-10 09:00 - 2025-11-13 19:00 | Gray Room 3, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
The IBS-MultiDark-IFT Workshop is a regular event organized jointly by MultiDark and IBS-CTPU, this year reaching its tenth anniversary.
The aim of the workshop is share ideas, foster collaborations, and to discuss recent developments in the field of axion and Dark Matter physics.
The second week, November 10-13, will focus on Dark Matter/Axions.
PROGRAM
Monday, Nov. 10:
(Chair: Alejandra)
15.15h: welcome (Sven & Miguel Angel)
15.30h: Chui-Fan Kong (CTPU/IBS)
“Testing neutrino mass origins with supernova neutrinos”
16.00h: Marina Cermeno (UPM)
“New probes of supernova axion-like particles in neutrino water Cherenkov detectors”
16.30h: coffee
(Chair: Marina)
17.00h: Mario Reig (CERN)
“Testing the heterotic string theory with the axion-photon coupling”
18.00h: reception

Tuesday, Nov. 11:
(Chair: David)
10.00h: Sven Heinemeyer (IFT)
“SUSY DM in GUTs: Fitting the LHC Excesses”
10.30h: Suruj Jyoti Das (CTPU/IBS)
“Affleck-Dine origins of Baryons, Dark Matter and Inflation”
11.00h: coffee
(Chair: Sven)
11.30h: Jose Valle (IFIC)
“Collider signatures of fermionic scotogenic dark matter”
12.00h: Iván Coarasa (UZ)
“Eight Years of Dark Matter Search at the Canfranc Underground Laboratory with ANAIS”
12.30h: Elias Lopez Asamar (IFT)
“Direct searches for dark matter in the sub-GeV regime”
13.00h: lunch
(Chair: Jose)
15.30h: Alejandra Aguirre Santaella (UV)
“New insights on low-mass dark matter subhalo tidal tracks via numerical simulations”
16.00h: David Alonso-González (IFT)
“Cornered but alive: GeV-scale thermal dark matter from dark photons”
16.30h: coffee

Wednesday, Nov. 12:
11.00h: coffee
(Chair: Mario)
11.30h: Sang Hui Im (CTPU/IBS)
“The EDM inverse problem”
12.00h: Sougata Gangly (CTPU/IBS)
“Consistent N_eff fitting in big bang nucleosynthesis analysis”
12.30h: discussion time
13.00h: lunch
(Chair: Sang Hui)
15.30h: Huayang Song (CTPU/IBS)
“Mediator-induced Decay Chains from Non-Minimal Dark Sectors and Multi-Jet Collider Signatures”
16.00h:Karen Macías Cárdenas (IFT)
“Cooling core-collapse supernovae with neutrinophilic dark sectors”
16.30h: coffee
21.00h: workshop dinner

Thursday, Nov 13
(Chair: Miguel Angel)
10.30h: Andrew Buchanan (IFT)
“High Mass Dark Matter Searches With the High Speed LMC”
11.00h: coffee
11.30h: Gaetano di Marco (IFT)
“The interconversion between gamma rays and ALP across various astrophysical environments: a new numerical approach”
12.00h: Pedro Jose de la Torre Luque (IFT)
“Multimessenger constraints for electrophilic feebly interacting particles”
12.30h: farewell

Cosmology Journal Club
2025-11-11 14:00 - 15:00, 2025-11-25 14:00 - 15:00
Every Tuesday at 2:00 PM in the discussion room on the 5th floor.
Join the IFT cosmology/gravity journal club at benty-fields.com to vote for papers and volunteer to present them.

SPS Journal Club: Holographic constraints on AdS flux vacua
2025-11-13 12:00 - 13:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Antonia Paraskevopoulou (Munich, Max Planck Inst. and LMU Munich)
Venue & Time: Red Room / 12:00
Abstract: In this talk, I will argue that the covariant entropy bound poses non-trivial restrictions on anti-de Sitter(AdS) flux vacua. After motivating the bound on AdS, we will see how it naturally arises in the context of the supergravity equations of motion, based on some reasonable assumptions. In four dimensions, we argue that the bound suggests a lower bound on the superpotential, as we will verify in examples. Based on work in progress with N. Cribiori and T. Van Riet.

Seminar: 'BipoSH: Structured test bed for cosmic isotropy violation'
2025-11-13 15:00 - 16:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Tarun Souradeep (Raman Research Institute, Bengaluru, India)
Venue & Time: Red Room / 3:00 PM
Abstract: The Cosmological Principle, a fundamental tenet of the ‘standard model of cosmology’, predicates a statistically isotropic distribution of fluctuations in the measured cosmic microwave background (CMB) temperature and polarization sky maps. Enigmatic anomalies claimed in the WMAP and Planck CMB sky maps, and some other recent observations, could challenge the standard model. However, these claims need to be cast in an objective mathematical framework and established with statistical rigor. Bayesian inference of the underlying covariance structure of random fields on the sphere in the Bipolar Spherical Harmonic (BipoSH) representation, developed in our research program, provides such a framework. We review some recent inferences drawn from Planck data and discuss the future prospects with proposed CMB observations.

Charla abierta: 'Los fundamentos invisibles de la naturaleza'
2025-11-15 11:00 - 12:00
En 2025 celebramos el centenario de la mecánica cuántica, una revolución científica que transformó nuestra visión del mundo al revelar que, en lo más profundo de la naturaleza, rigen leyes desconcertantes, como el efecto túnel, el principio de incertidumbre, la superposición, el entrelazamiento… A través de esta charla divulgativa descubriremos la ciencia de los universos paralelos o las realidades superpuestas y veremos cómo la mecánica cuántica impacta en nuestra vida cotidiana: microchips, láseres o resonancias magnéticas, además de ordenadores cuánticos que se están construyendo hoy en día. ¿Qué nos depara el futuro próximo? Acércate y alucina.
Se trata de una actividad divulgativa para acercar la física cuántica al público general, combinando ciencia, reflexión y naturaleza. Incluye la charla ‘100 años de física cuántica: los fundamentos invisibles de la naturaleza’ por Alberto Casas, investigador Instituto de Física Teórica y Profesor de Investigación del CSIC.
Información práctica
Personal participante: Alberto Casas, investigador Instituto de Física Teórica y Profesor de Investigación del CSIC
A quién va dirigido: público general a partir de 14 años.
Aforo: 120
Lugar: Real Jardín Botánico-CSIC. Plaza de Murillo 2, Madrid.
Acceso movilidad reducida: sí
Inscripciones*: a través del siguiente formulario.
*El día de la actividad, la charla tendrá acceso libre hasta completar aforo.

Colloquium: 'The Promise of Gravitational Wave Cosmology'
2025-11-17 15:00 - 16:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Tarun Souradeep (Raman Research Institute, India)
Venue & Time: Red Room / 3:00 PM
Abstract: The 10th anniversary of the first detection of gravitational waves (GWs) is an apt time to assess the promise of this across all GW windows to the understanding of our Universe. The talk briefly reviews the status and successes achieved. The focus will be on the promise for cosmology of the upcoming LIGO-India observatory in early 2030s, LISA space mission in mid 2030s, and the proposed next generation cosmic microwave background and terrestrial/lunar missions.

Cosmology Journal Club
2025-11-18 14:00 - 15:00, 2025-12-02 14:00 - 15:00 | Discussion room 5th floor, C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, Madrid, 28049, Spain

Seminar: 'Quantum Field Theory, an Overview'
2025-11-18 15:00 - 16:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Anthony Zee (Kavli Institute for Theoretical Physics and the Department of Physics, University of California, Santa Barbara, CA, USA)
Venue & Time: Red Room / 3:00 PM
Abstract: I give an overview and appreciation of quantum field theory, the most precisely tested theory in physics. The talk is addressed to those without any knowledge of quantum field theory. It is based on my textbook Quantum Field Theory in a Nutshell and my semi-popular book Quantum Field Theory, as Simply as Possible (both published by Princeton University Press.)

Pheno Journal Club
2025-11-18 15:00 - 16:00, 2025-12-02 15:00 - 16:00 | Gray Room 3, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Every Tuesday at 15:00 in Grey Room 3.

Seminar: Average-case quantum complexity from glassiness
2025-11-19 11:30 - 13:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Alexander Zlokapa (MIT)
Venue & Time: Red Room / 11:30
Abstract: In the classical setting, glassiness characterizes many natural problems (e.g., random k-SAT) and underlies average-case hardness by obstructing a family of “stable” classical algorithms (e.g., constant-time Langevin dynamics). In this work, we develop analogous quantum results. Our techniques, based on quantum optimal transport, differ significantly from classical probabilistic approaches due to the sign problem in the absence of a known eigenbasis. We show that quantum glassiness obstructs stable quantum algorithms, including constant-time Lindbladian dynamics (even when starting from the maximally mixed state). Using the replica trick, we also find that random 3-local Pauli Hamiltonians are quantumly hard and give evidence that random k-local Hamiltonians are quantumly easy for sufficiently large constant k. This differs from the analogous classical (Ising, glassy phase for all k) and fermionic (SYK, never glassy for any k) k-local ensembles. (Talk based on arXiv:2510.08497.)

SPS Journal Club: 'Flux Backtracking and Decoupling of Scale Separated AdS Vacua'
2025-11-20 12:00 - 13:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Fien Apers (IFT)
Venue & Time: Red Room / 12:00
Abstract: I will explain how the flux backtracking method (https://arxiv.org/pdf/2506.03314) can be used to reconstruct the D-brane configuration whose near-horizon region realises the DGKT vacua. As an application, I will show how this reconstructed geometry allows one to verify whether the corresponding D-brane theory decouples from bulk gravity.

Seminar: 'Classical constant electric fields and the Schwinger effect in de Sitter'
2025-11-20 15:00 - 16:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Roberto Vega-Morales
Venue&Time: Red Room / 15:00
Abstract: In this talk I will discuss constant classical electric fields and the Schwinger effect in de Sitter space, which has potential implications for magnetogenesis and inflationary dark matter production. I will first go through the conditions for sustaining a constant electric field in de Sitter space before reviewing the calculation of the Schwinger current, pointing out puzzling results in previous calculations found in the literature and how we have resolved them. I will then comment on current and future directions related to this topic. This talk is based on arXiv:2508.14973.

Old Journal Club en la Facultad: "Rotura de simetría y mecanismo de Higgs"
2025-11-20 17:30 - 18:30
Speaker: Marta F. Zamoro (IFT)
Venue & Time: Aula M15-201. Facultad de Ciencias, UAM / 17:30

2 Minutes Meeting
2025-11-24 10:00 - 13:00
The Institute for Theoretical Physics (IFT) and the Department of Theoretical Physics (DFT) would like to invite you to the “2 Minutes Meeting”, which will take place on Monday, November 24 at 10:00 AM in the Aula Polivalente (UAM).

This event is open to all DFT and IFT members and aims to help us get to know each other better in a relaxed and informal setting. Each participant will have about 2 minutes to introduce themselves and share some of their personal or recreational interests.

If you’d like to use one slide during your brief presentation, you may send one only slide to comunicacion@ift.csic.es before Friday, November 21.

We’ll finish with a coffee at 13:00 PM in the Sala de Profesores – Ramiro Cafeteria.

We hope you’ll take part — it’s a perfect moment to meet and connect with all your colleagues.

Join us!

Seminar: 'Gravitational Lensing of Waves: a new window into cosmology and fundamental physics'
2025-11-24 15:00 - 16:00
Speaker: Miguel Zumalacárregui from Max Planck Institute for Gravitational Physics (Albert Einstein Institute).
Venue&Time: Red Room / 3:00 PM
Abstract: Gravitational lensing, the bending of light by gravity, is essential for interpreting astronomical observations and provides key insight into astrophysics, cosmology, and fundamental physics. A new frontier in gravitational lensing intersects with another key prediction of Einstein’s theory: gravitational waves, fluctuations of space-time produced by the collision of black holes and neutron stars. Like light, gravitational waves are deflected and magnified by the intervening matter distribution, but their unique properties (low frequency, lack of absorption and ab-initio emission models) enable novel signatures and applications. I will present the phenomenology of lensed gravitational waves and the science they will deliver to identify high-redshift sources and probe dark-matter and new gravitational fields. As guiding example I will focus on GW231123: the first compelling lensed black hole merger candidate, its interpretation and consequences.

Pheno Journal Club: 'Is the Strong CP Problem Really a Problem?'
2025-11-25 15:00 - 16:00 | Gray Room 3, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Giulio Barni (IFT)
Venue & Time: 14:30 – 15:30
Abstract: The vanishingly small value of the QCD θ-angle inferred from neutron EDM bounds is usually taken as evidence for the Strong CP Problem, prompting a wide range of proposed solutions. In this talk, I will first review what the Strong CP Problem is: why a generic θ term in QCD leads to large CP violation, and how current experiments force θ ≲ 10e-10. I will then summarize the main solution strategies, including the Peccei–Quinn axion, parity- or CP-based models, and other less conventional ideas. The second part of the talk will focus on a more conceptual question raised in recent years: does the Strong CP Problem actually exist, or could θ be unphysical once confinement and the full structure of QCD are properly taken into account? Building on the recent analysis of Benabou, Hook, Manzari, Murayama and Safdi (arXiv:2510.18951), I will discuss this debate, highlighting what lattice QCD teaches us about θ-dependence, topological sectors, and the neutron EDM.

EDI Trainings: 'Intersectionality. Reflection on identity, privilege and positioning in academia'
2025-11-25 15:30 - 17:00 | Blue Room, Instituto de Física Teórica (IFT) - C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Shannah Khan. Director of Intersect Madrid
Venue & Time: Blue Room / 3:30 PM
Abstract: This workshop offers a space for reflection and dialogue to explore how our personal identities, experiences, and social positions influence the way we participate in academic contexts. Through participatory activities, it seeks to foster a deeper understanding of intersectionality and the role that privilege and position play in our interactions and perspectives within academia.

Técnicas Computacionales en la frontera de la Transición Digital para Física de Partículas y Cosmología
2025-11-26 10:00 - 11:00 | Discussion room 5th floor, C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, Madrid, 28049, Spain
Defensa de la memoria anual 2025 del programa Momentum “Técnicas Computacionales en la frontera de la Transición Digital para Física de Partículas y Cosmología”
Speaker: Emilio Ambite

String, Pheno and the Swampland Journal Club: 'Anomaly-induced vanishing of brane partition functions'
2025-11-27 12:00 - 13:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Michelangelo Tartaglia (IFT)
Venue & Time: Red Room / 12:00
Abstract: In the presence of ‘t Hooft anomalies, backgrounds for the symmetries of a quantum field theory can lead to non-conservation of Noether currents, or more generally, to the presence of charged insertions in the path integral. When there is a net background charge, the partition function evaluated on closed manifolds will vanish. For anomalous symmetries, this statement can also be understood as the anomaly theory giving rise to a non-trivial anomalous phase for the partition function even for “rigid” transformations which leave all background fields unchanged. We use the generalisation of this second viewpoint to the setting of anomalous higher-form symmetries in order to show vanishing of the partition function for a number of examples, both with and without a Lagrangian description. In particular, we show how to derive from these considerations the analogue of the Freed-Witten anomaly cancellation condition for the M5-brane, and also that for the D3-brane in S-fold backgrounds.

Seminar: Constraining Muon decay parameters from CEvNS measurements at Spallation Sources
2025-11-27 15:00 - 16:00
Speaker: Suraj Prakash, IFIC (Valencia)

Venue&Time: Red Room / 3:00 PM
Abstract: The talk will present a study of the sensitivity of COHERENT-like experiments to non-standard neutrino interactions within the vWEFT framework, i.e. low-energy EFT with additional right-handed Dirac neutrinos. Our analysis incorporates, for the first time, flavor-general New Physics effects in both neutrino production (from pion and muon decays) and neutrino detection, through Coherent Elastic Neutrino-Nucleus Scattering (CEvNS). As a special case, we will highlight how CEvNS data provide an alternative probe for muon decay parameters, for neutrino experiments where muon decay is a source of neutrinos. We will further illustrate how the results can be conveniently formulated in compact form and the ease with which they can be implemented in existing or future analyses using effective nuclear charges. Finally, We will discuss numerical results based on current COHERENT data, and also present estimates for the sensitivity of future measurements.

PhD dissertation: 'Shedding light on extended scalar sectors'
2025-11-28 12:00 - 14:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
By Víctor Enguita
Venue & Time: Red Room / 12:00
Abstract:
The Standard Model has a number of traits which are surprising from the theoretical perspective and may hint the presence of some underlying hidden structure beyond the SM. In this thesis, we explored some of the open problems which materialize from those traits and could be solved by the presence of an extended scalar sector. First, we considered axion-like particles (ALPs) using an Effective Field Theory (EFT) approach and imposed improved limits on their CP-odd couplings to fermions. The remainder of the thesis was devoted to the Electroweak hierarchy problem (EWHP). We presented two original works which follow two different guiding principles, one traditional and the other rather innovative: symmetry and near-critical dynamics. The first among these works presents non-abelian discrete symmetries as able to suppress large radiative corrections and stabilize the masses of scalar particles. In the second contribution, we argue that the small observed mass of the Higgs could be a trademark of the near-criticality of the Higgs sector, backed by the observation that every parameter in the Higgs potential seems in fact to also be near-critical. We explore the consequences of this fact using the so-called “Higgs metastability bound” in the case of a concrete model—the low-scale Majoron model—and demonstrate that this justification of the mass of the Higgs implies new experimental signals in future experiments and in particular, in the future colliders. We argue that this conclusion is actually more general and should apply to wider contexts than the concrete model analysed.
Supervisors: Belén Gavela & José Miguel No

Seminar: Quantum simulation of lattice gauge theories with Rydberg atom arrays
2025-12-01 15:00 - 16:00 | IFT Seminar Room/Red Room, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Daniel González Cuadra (IFT)
Venue&Time: Red Room / 15:00
Abstract: Lattice gauge theories (LGTs) describe a broad range of phenomena in condensed matter and particle physics. A prominent example is confinement, responsible for bounding quarks inside hadrons such as protons or neutrons. When quark-antiquark pairs are separated, the energy stored in the string of gluon fields connecting them grows linearly with their distance, until there is enough energy to create new pairs from the vacuum and break the string. While such phenomena are ubiquitous in LGTs, simulating the resulting dynamics is a challenging task. In this talk, I will report the observation of string breaking in synthetic quantum matter using a programmable quantum simulator based on neutral atom arrays [Nature 642, 321–326 (2025)]. I will first show how a (2+1)D LGT with dynamical matter can be efficiently implemented when the atoms are placed on a Kagome geometry, with a local U(1) symmetry emerging from the Rydberg blockade, while long-range Rydberg interactions naturally give rise to a linear confining potential between pairs of charges. In the experiment, we probe string breaking in equilibrium by adiabatically preparing the ground state of the atom array in the presence of defects, distinguishing regions within the confined phase dominated by fluctuating strings or by broken string configurations. Finally, by harnessing local control over the atomic detuning, we quench string states and observe string breaking dynamics exhibiting a many-body resonance phenomenon. As an outlook, I will present a roadmap to further explore phenomena in high-energy physics using programmable quantum simulators.

Holo Club: 'Complexity equals anything for multi-horizon black holes'
2025-12-02 11:30 - 13:00 | Gray Room 3, Instituto de Física Teórica (IFT) -C. Nicolás Cabrera, 13-15, Fuencarral-El Pardo, Madrid, 28049,, Spain
Speaker: Hong-Yue Jiang (Lanzhou University)
Venue&Time: 11:30 / Gray Room 3
Abstract: We investigate the “complexity equals anything” proposal with codimension-one and codimension-zero gravitational observables for multi-horizon black holes, using the Bardeen-AdS class black hole as an example. In particular, we compare the results with the “complexity equals volume” (CV) proposal and find that the generalized volume complexitiy enables the probing of a more complete black hole interior, that is, all spacetime regions where the blackening factor $f(r)<0$. This is the advantage brought by the flexibility of this holographic complexity conjecture. In addition, we compute the codimension-zero gravitational observables derived from various geometric quantities and show that these constructions can effectively differentiate the distinct interior regions of the black hole.

GRASS Seminar: 'Electric-magnetic duality of dyonic Kerr-Newman-NUT-AdS spacetimes'
2025-12-02 15:00 - 16:00
GRASS (GRAvity, Supergravity & Superstrings) Seminar
Speaker: Cristóbal Andrés Corral (Universidad Adolfo Ibáñez, Chle)
Venue & Time: Red Room / 15:00
Abstract: We discuss the (anti-)self-duality conditions under which the electric and magnetic parts of the conserved charges of the dyonic Kerr-Newman-NUT-AdS solution become equivalent. Within a holographic framework, the stress tensor and the boundary Cotton tensor are computed from the electric/magnetic content of the Weyl tensor. The holographic stress tensor/Cotton tensor duality is recovered along the (anti-)self-dual curve in parameter space. We show that the latter not only implies a duality relation for the mass but also for the angular momentum. The partition function is computed to first order in the saddle-point approximation and a BPS bound is obtained. The ground state of the theory is enlarged to all the (anti-)self-dual configurations when the SO(4) and U(1) Pontryagin densities are introduced. We demonstrate this at the level of the action and variations thereof.
