Marc Henneaux (Collège de France, Intl. Solvay Inst. and  Brussels U.)
Title: Asymptotic Symmetries and Algebras: a review
Abstract: A review of asymptotic (more generally, boundary) symmetries will be given in the context of the Hamiltonian formulation. General features (such as the form of the symmetry generators and the structure of the algebra) as well as specific examples will be covered.  A particular attention will be paid to asymptotically flat spaces and the asymptotic BMS algebra, where nonlinear redefinitions will be shown to yield a supertranslation-invariant angular momentum.
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Paolo Creminelli (ICTP, Trieste)
Title: Primordial Non-Gaussianity: the f_NL ~ 1 threshold
Abstract: I will review the theoretical and experimental status in the search of primordial non-Gaussianity, focussing on some recent developments and ideas.
In particular I will try to answer the question: what are we going to learn when experiments will be able to probe f_NL ~ 1?
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Yashar Akrami (IFT, Madrid)
Title: Large-scale cosmic anomalies: current status, future prospects, and possible explanations
Abstract: Even though the current observational data show an extremely high level of agreement with predictions of the standard model of cosmology, LambdaCDM, the cosmic microwave background (CMB) temperature fluctuations measured by the WMAP and Planck satellites have shown a number of persistent anomalous features on large-angular scales that are unexpected or extremely unlikely in LambdaCDM cosmology. These anomalies, which are properties of the observed sky and not instrumental artifacts, are all related to violation of statistical isotropy, and even though they could, individually taken, be statistical flukes, they may also be hints of new physics beyond the standard cosmological model. In this talk, after providing a critical review of the CMB large-angular-scale anomalies, their history, and their current status, I will discuss some of the existing explanations for the features, ranging from the fluke hypothesis and astrophysical foregrounds within LambdaCDM to different physical models beyond the standard picture, in particular the possibility that the Universe has a non-trivial topology, and will review phenomenological expectations for each explanation. I will argue that, in addition to the new perspectives on existing data that the powerful and continuously advancing computational and statistical techniques may provide, it is also essential to investigate the anomalies further with upcoming and future high-precision cosmological data, including observations of the CMB polarization and the cosmic large-scale structure. This is because any observations of similar or related anomalies in any data sets other than the CMB temperature sky will ameliorate concerns about look-elsewhere penalties for the a posteriori statistical characterization of the CMB temperature anomalies while dramatically increasing the statistical significance of the features to a level which will inevitably force us to revise or rethink the standard model of cosmology. Finally, I will discuss potential connections between the CMB anomalies and the reported tensions in the measured values of the cosmological parameters of the LambdaCDM model and argue that a combination of these tensions and anomalies may provide a smoking gun for the existence of new physics beyond the standard model of cosmology.
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Stefano Profumo (University of California, Santa Cruz)
Title: Black Holes as Dark Matter
Abstract: The possibility that some of the black holes in the universe have a non-stellar origin and that they play a significant role in cosmology - including being some or all of the dark matter - is both timely and intriguing. I will review the status of the field, describe search strategies and future prospects for detection across many decades in mass, discuss how primordial black holes could seed both baryonic and particle dark matter in the very early universe, and argue that the search for sub-solar mass black holes may lead to a deeper understanding of the elusive Galactic "rogue planets".

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Ahmed Almheiri (NYU, Abu Dhabi)
Title: A review on quantum black holes: progress and open problems
Abstract: Our understanding of quantum black holes has come a long way from the initial observations of Bekenstein and Hawking from roughly half a century ago. This talk will review our current understanding of black holes as quantum mechanical systems with finite Hilbert spaces and how it is supported by calculations using the gravity path integral. The talk will highlight several works over the past decade that implement such techniques to display different quantum mechanical aspects of black holes. Challenges and open problems will be discussed, especially those that relate to the nature of the interior.

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Sebastian Trojanowski (Copernicus Astron Ctr, Warsaw)
Title: BSM physics and neutrinos in the forward region of the LHC and beyond
Abstract: Forward physics at the Large Hadron Collider has entered its new era, with the ongoing searches for BSM species and neutrino physics program at FASER and SND@LHC experiments. In this talk, I will review the first results of these measurements and discuss the recent progress and status of the proposed extension, namely the Forward Physics Facility. I will also highlight selected interesting prospects for forward searches at future collider facilities.

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David Nichols (Virginia U.)
Title: Gravitational-wave memory effects from astrophysical sources
Abstract: Gravitational waves are a prediction of general relativity that were first directly measured in the previous decade by the LIGO and Virgo detectors, mostly from the collisions of black holes. Currently, these ground-based detectors observe a black-hole merger about once every other day. New gravitational-wave frequency bands are opening, notably with pulsar timing arrays, which have found strong evidence for a stochastic gravitational-wave background from supermassive black-hole mergers. A space-based gravitational-wave detector, LISA, is scheduled to launch in the 2030s, and it will detect gravitational waves at intermediate frequencies between pulsar timing arrays and ground-based detectors. These observations have and will continue to provide insights into the nonlinear and dynamical regime of general relativity. One such prediction of general relativity that has not yet been observed is the gravitational-wave memory effect: a change in the spacetime metric that persists after a burst of gravitational waves passes by a detector. In this talk, I will review the history of the memory effect, the different astrophysical sources that produce it, and the detection prospects for the effect. I will also discuss the more recently understood relationship between the memory effects and the asymptotic symmetries and charges of isolated systems in general relativity. This later perspective has led to the prediction of many generalizations of the memory effect, which I will also review.

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Michele Maltoni (IFT, Madrid)
Title: Phenomenology of neutrino oscillations
Abstract: In this talk I will review where we stand with the research activity on neutrino oscillations, with particular attention to the phenomenological aspects and the determination of the oscillation parameters.  A special emphasis will be put on the synergies between different classes of experiments, showing how the complementarity between solar, atmospheric, reactor and accelerator data can help to solve the parameter degeneracies commonly arising in both standard and non-standard neutrino scenarios.
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Cliff Burgess (McMaster U. and Perimeter Inst.)
Title: UV Priors for Cosmic Acceleration
Abstract: We live in remarkable times: the recent advent of gravitational-wave observations allows testing gravity in a strongly relativistic regime. We also have plausible candidates for UV physics that can reconcile General Relativity with Quantum Mechanics. Primordial cosmic fluctuations might even provide direct observational evidence for gravitating quantum physics at very high energies. But a central organizing feature of Nature - Decoupling - beautifully explains why low-energy measurements are largely insensitive to UV details and so at first sight seems to thwart the extraction of fundamental insights about UV physics from astrophysical or cosmological observations. This talk argues that a few UV features can penetrate the fog of decoupling in interesting ways. Decoupling constraints are less pressing (but still present) for inflationary expansion in the very early universe, but are crucial at the low energies being explored in the present-day universe. I argue that decoupling ideas point to a class of late-universe cosmologies that are relatively poorly explored.

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Hep-ph

Sovan Chakraborty (Indian Inst. Tech, Guwahati, India)
Title: Fast Oscillations in Supernovae Neutrinos: Beyond Active Flavors
Abstract: Sterile neutrinos are the hypothetical singlet fermions which interact with ordinary matter only through mixing with the active neutrinos. In the context of Supernovae (SN), the generation of active-sterile through Mikheyev-Smirnov-Wolfenstein (MSW) conversions  for the eV mass sterile species have been found to affect the SN explosion and nucleosynthesis in an appreciable manner. Motivated from this, it becomes interesting to probe the effect of these kinds of MSW conversions on the fast flavor conversions (FFC’s) of neutrinos occurring deep inside the SN core. In this talk, we discuss the possible impact of the active-sterile neutrino  oscillations on the zero crossings in the neutrino flavor lepton number in a 2+1 scenario (2 active and 1 sterile species) as the presence of the latter is a crucial factor in the development of FFC’s. We found, through a representative example of an outer resonance, that the corresponding change in the number of electron neutrino and antineutrino due to MSW  resonance can potentially modify the subsequent zero crossings and thus affect the occurrence  of FFC’s significantly.

Nicolás Bernal (NYU, Abu Dhabi)
Title: Thermal Dark Matter with Low-Temperature Reheating
Abstract: We explore the production of thermal dark matter (DM) candidates (WIMPs, SIMPs, ELDERs and Cannibals) during cosmic reheating. Assuming a general parametrization for the scaling of the inflaton energy density and the standard model (SM) temperature, we study the requirements for kinetic and chemical DM freeze-out in a model-independent way. For each of the mechanisms, up to two solutions that fit the entire observed DM relic density exist, for a given reheating scenario and DM mass. As an example, we assume a simple particle physics model in which DM interacts with itself and with SM through contact interactions. We find that low-temperature reheating can accommodate a wider range of couplings and larger masses than those permitted in the usual instantaneous high-temperature reheating. This results in DM solutions for WIMPs reaching masses as high as 10^14 GeV, whereas for SIMPs and ELDERs, we can reach masses of 10^13 GeV. Interestingly, current experimental data already constrain the enlarged parameter space of these models with low-reheating temperatures. Next-generation experiments could further probe these scenarios.

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Manibrata Sen (MPIK, Heidelberg)
Title: Boosting galactic dark matter with relic supernova neutrinos
Abstract: Diffuse neutrinos from past supernovae in the Universe present us with a unique opportunity to test dark matter (DM) interactions. These neutrinos can scatter and boost the DM particles in the Milky Way halo to relativistic energies allowing us to detect them in terrestrial laboratories. In this talk, I will discuss how the consideration of energy-dependent cross-sections for DM interactions can significantly affect constraints previously derived under the assumption of constant cross-sections, modifying them by multiple orders of magnitude. I will focus on generic models of DM-neutrino and electron interactions, mediated by a vector or a scalar boson, and discuss new limits obtained on DM-neutrino and electron interactions for DM with masses in the range $\sim (0.1, 10^4)$~MeV, using recent data from XENONnT, LUX-ZEPLIN, and PandaX-4T direct detection experiments.
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Saeed Abbaslu (IPM, Tehran)
Title: Searching for Axial Neutral Current Non-Standard Interactions of neutrinos by DUNE-like experiments
Abstract: The increasingly precise neutrino experiments raise the hope for searching for new physics through studying the impact of Neutral Current (NC) Non-Standard Interactions (NSI) of neutrinos with matter fields. Neutrino oscillation experiments along with the Elastic Coherent $\nu$ Nucleus Scattering (CE$\nu$NS) experiments already set strong bounds on all the flavor elements of the ``vector" NC NSI. However, ``axial" NC NSI can hide from these experiments. We show how a DUNE-like experiment can probe these couplings by studying NC Deep Inelastic Scattering (DIS) events. We find that strong bounds can be set on the axial NC NSI of neutrinos with the $u$, $d$, and $s$ quarks. We show that using both the near and far detectors, a DUNE-like experiment can significantly improve the present bounds on all the flavor elements. 

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Masud Mehedi (Chung-Ang U., Seul, Korea)
Title: Probing Large Extra Dimension at DUNE using beam tunes
Abstract:

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Yuber F. Perez-Gonzalez (IPPP, Durham U., UK)
Title: Gravitational Particle Production and Leptpgenesis
Abstract: In a curved spacetime, the definition of particles depends on the observer's frame of reference. Consequently, in non-stationary spacetimes, such as those present in the Early Universe during and after inflation or during the gravitational collapse leading to black hole formation, a substantial production of particles may occur. This talk explores the impact of gravitational particle production (GPP) on scenarios generating the observed matter-antimatter asymmetry, particularly in the context of leptogenesis. We first examine the effects of cosmological GPP, showing that the observed asymmetry could be produced without requiring the Universe to be reheated to temperatures matching the right-handed neutrino masses. Additionally, we investigate the interplay between leptogenesis and primordial black holes, demonstrating that Hawking evaporation can either enhance or suppress the generated asymmetry, depending on the specific black hole parameter space.

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Hep-th

Luca Ciambelli (Perimeter Inst. Theo. Phys.)

Batoul Banihashemi (UC Santa Cruz)
Title: Gravity at finite cutoff
Abstract: In this talk I describe thermodynamics of gravitational systems with conformal boundary conditions. The main focus is on comparing the series of subextensive terms in the free energy to predictions from thermal effective field theory. We observe that while there is agreement in terms of the high temperature expansion structure, the first subextensive correction to the free energy is negative. This violates a conjectured bound on this coefficient in quantum field theory, which we interpret as a signal that gravity does not fully decouple in the putative boundary dual.

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Aritra Banerjee (Birla Inst. Tech. Sci. India)
Title: Strings near black holes are Carrollian
Abstract: I will talk about classical closed bosonic strings probing the near-horizon region of a non-extremal black hole and show that this corresponds to understanding string theory in the Carroll regime. This is done by first performing a Carroll expansion and then a near-horizon expansion of a closed relativistic string, subsequently showing that they agree. As a consequence of the Carroll expansion, I will show that two different regimes exist, that of two different Carroll strings: a magnetic one and an electric one. 

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Reza Javadinezhad (New York Uni & IPM)
Title: Angular momentum flux non-invariance under supertranslations
Abstract: After a short review of the BMS group, I will discuss the non-invariance of the angular momentum flux, which is an important quantity from both theoretical and numerical perspective. Theoretically, it's important to eliminate ambiguity in the definition of the flux, while in simulations, it has a direct impact on the results. I will conclude by explaining the solution to this problem.

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Ida Rasulian (School of physics, IPM)
Title: Strings and Virasoro Sandwich Conditions
Abstract: We revisit the canonical quantization of free bosonic closed string theory and observe that the physicality of states requires vanishing of the worldsheet Virasoro algebra generators sandwiched between any two physical states. This requirements yields four classes of physical states, depending on discrete worldsheet symmetries: parity and time reversal. The usual string states which are highest weight states of the Virasoro algebra, preserve both, while the other new three classes  break one or both. We apply our formulation to an accelerated worldsheet with horizons, initiating the worldsheet formulation of a thermal string theory and strings probing horizon of black holes.
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V. Taghiloo(IPM)

Cosmology

Tomi Koivisto (Inst. of Phys., Uni. of Tratu)
Title: SO(4) YM theory of gravity and cosmology
Abstract: A Yang-Mills theory of spacetime and gravity is formulated in terms of the compact gauge group SU(2)xSU(2). A symmetry-broken SU(2) phase of the theory allows a simplified description of the gravitational dynamics, which can be mapped to the conventional pseudo-Riemannian geometrical description of general relativity in the presence of a cold dark matter. The symmetric phase is the "ground state" of the theory wherein the composite pseudo-Riemannian metric vanishes. It is speculated that the initial conditions of the Universe could be explained by its emergence from the symmetric phase

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Mohammad Malekjani (Bu Ali Sina U.)

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Krzysztof-Jan Turzynski (University of Warsaw)
Title: Preheating and gravitational waves from geometrical destabilization
Abstract: Multi-field models of inflation with negative field-space curvature may lead to geometrical destabilization of non-adiabatic, or spectator, scalar perturbations. This phenomenon can occur at the end of inflation, e.g. in alpha-attractor models of inflation, or during inflation. Recent numerical lattice simulations shed light onto dynamics of the coupled scalar perturbations when such geometrical destabilization occurs. In the end-of-inflation geometrical destabilization, a rapid growth of the spectator perturbations can lead to preheating and associated production of gravitational waves, to the extent that alpha attractor T-models can be constrained or even ruled out by present observations. The middle-of-inflation geometrical destabilization turns out a short-lived phenomenon and a negative feedback loop prevents field fluctuations from growing indefinitely. As a result, fields undergoing geometrical destabilization are merely shifted to a new classical configuration corresponding to a uniform value of the spectator field within a Hubble patch.

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Ranjini Mondol (IIS, Bangalore)

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Kohei Kamada (Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences)
Title: Primordial magnetic fields and baryon isocurvature problem
Abstract: Gamma-ray observations of blazars suggest the existence of the intergalactic magnetic fields and their origin is interest for both astro physicsts and cosmologists. Among several proposals, magnetogenesis in the early Universe is an interesting option since it might also be a probe for the physics beyond the Standard Model of particle physics. Recently, it has also been proven that the baryon asymmetry of the Universe can be also generated if the magnetic fields are produced before the electroweak symmetry breaking with helicity without imposing any new physics. However, baryon isocurvature perturbations are also generated at the scale of the magnetic field coherence length in the mean time, which is constrained by the inhomogeneous Big Bang Nucleosynthesis. Note that this is an inevitable consequence of the Standard Model of particle physics.
In this talk, I give generic constraints of the hypermagnetic field properties generated before the electroweak symmetry breaking. Noting that the baryon isocurvature perturbations are generated even from non-helical magnetic fields, I show that with reasonable parameter sets for the Standard Model of particle physics and magnetic field evolution laws, the intergalactic magnetic fields suggested by the blazar observations are hardly explained solely by the hypermagnetic fields generated before the electroweak symmetry breaking. Helical hypermagnetic fields can still be the origin of the present baryon asymmetry of the Unvierse, but we need an additional magnetogenesis or an unknown magnetic field amplification mechanism.

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Adrià Gómez-Valent (ICC, Barcelona U.)
Title: Analysis of the tension between 3D and 2D BAO measurements

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