PASCOS 2026

Contribution List

107. 4d N=4 string islands from asymmetric orbifolds

Elisa Iris Marieni (University of Southampton)

Contributed Talk

String islands are isolated points in the space of string vacua that have no moduli except the dilaton, enjoy rank reduction and lead to consistent pure supergravity theories. Asymmetric orbifold constructions are powerful tools that enable us to access these points in the moduli space that are inaccessible to more standard string compactification techniques. In this talk, we classify all...

130. A Holographic Dark Energy Model in Light of Recent Data

Patrick Adolf

Contributed Talk

The latest data release of the DESI collaboration shows an increasing preference for time-depending dark energy models compared to the $\Lambda$CDM model.
In our work, we construct a holographic dark energy model motivated by the work of Cohen, Kaplan and Nelson (CKN) which proposed to use the Hubble horizon as an IR cutoff and connect it to the UV cutoff of the theory.
We take the resulting...

88. A Homothetic Extension of the Standard Model: Geometric UV-Regularization via Twisted Hodge--de Rham Theory

Fereidoun Sabetghadam (Mechanical engineering department, science and research branch ,IAU, Tehran, Iran)

Poster

The short-distance singularities and infinite self-energies in classical and quantum field theories motivate the exploration of extended geometric structures. Recently [1,2], we introduced a homothetic extension of classical Weyl-integrable geometry by generalizing the conventional linear gauge transformations to affine homothetic transformations centered at a distinguished harmonic,...

129. A Lapse in the Cosmological Constant Problem

Benjamin Muntz (University of Nottingham)

Contributed Talk

We present a new mechanism for addressing the cosmological constant problem based on global constraints arising from a lapse function in a higher-dimensional gravitational theory. Inspired by Horava-Lifshitz gravity, we consider a 5d spacetime with anisotropic scaling along a compact extra dimension, while preserving Lorentz invariance in four dimensions. In the deep infrared limit, variation...

174. A Master Equation for Screening in Luminal Horndeski Gravity

Sergi Sirera (Institute of Cosmology and Gravitation)

Contributed Talk

Determining the active screening mechanism from a general scalar-tensor Lagrangian remains a significant challenge when testing modified gravity models against cosmological observations. In this talk, I will present a new diagnostic framework based on a systematic study of nonlinear cosmological perturbations in luminal Horndeski theories. I will outline the derivation of a master equation for...

39. A new model of spontaneous scalarization induced by curvature and matter

Zakaria Belkhadria (Université de Genève & Università di Cagliari)

Poster

Spontaneous scalarization is a mechanism that allows black holes to develop a non-trivial profile of a scalar field “scalar hair”because of tachyonic instabilities, enabling tests of gravity beyond General Relativity. Motivated by stability and threshold issues in Gauss-Bonnet scalarization, we propose a new model characterized by
two nonminimal couplings of the scalar field to both...

90. A positive definite formulation of vacuum decay

Shogo Matake (Kobe University)

Poster

First-order phase transitions can occur in the early universe depending on the structure of the Higgs sector. A crucial quantity for determining the cosmological consequences is the transition rate.

Recently, the tunneling potential method has been proposed as a new framework for computing transition rates, based on a positive-definite action formulation with O(4)-symmetry. This makes the...

133. A possible solution to the gallium anomaly moving beyond the leptonic wave function factorization

Luca Ferro (INFN Cagliari, University of Cagliari)

Contributed Talk

For over three decades, the gallium anomaly, a persistent discrepancy exceeding 5σ between measured and predicted neutrino capture rates on gallium-71 in the GALLEX, SAGE, and BEST experiments, has challenged the particle physics community. While frequently interpreted as evidence for short-baseline sterile neutrino oscillations, this scenario is increasingly in tension with recent bounds from...

209. A predictive curvaton from thermal misalignment

Takuya Okawa (SISSA)

Poster

Cold inflation provides an elegant explanation for the near homogeneity and flatness of the Universe. However, the simplest large-field models are disfavored by Planck CMB data, and fitting current observations typically requires inflationary potentials that appear fine-tuned from an effective field theory perspective. The curvaton mechanism alleviates this tension: a light spectator field...

131. A QCD vacuum motivated model of dynamical dark energy

Dong Ha Lee (University of Sheffield)

Contributed Talk

The nature of dark energy has been a growing point of debate in recent years, particularly after the DESI measurements of the Baryon Acoustic Oscillations. While frequentist metrics appear to indicate a growing preference for a dynamical dark energy, some bayesian approaches indicate otherwise. Beyond this, there also lies the question of whether there exists a physical motivation behind any...

213. A Solar Probe of Dark Matter Decay in the Galaxy

Maximilian Detering (King's College London)

Contributed Talk

Dark matter (DM) decay in the Galactic halo injects energetic $e^\pm$ that can inverse-Compton scatter (ICS) solar photons into $\gamma$ rays, producing a diffuse halo of emission around the Sun. We present the first quantitative study of this signal as a probe of decaying DM. Using 15 years of Fermi-LAT solar-halo data, we compute the heliocentric ICS signal and derive limits on the DM...

56. A universal scaling for induced gravitational waves during inflation

Martin Teuscher (LPSC Grenoble, France)

Contributed Talk

We consider the gravitational wave (GW) background induced by arbitrary source fields that are amplified during inflation. We first conduct a very general analysis where the associated tensor spectral index $n_T$ is shown to be given, under minimal assumptions, by a simple and ready-to-use formula. Remarkably, we demonstrate that during slow-roll inflation $n_T$ becomes completely independent...

57. Advancing Cosmology

Pierros Ntelis (Harbin Institute of Technology and Institute of Theoretical Physics, National University of Uzbekistan)

Poster

In this talk, I will introduce the polyLCDM model, a simple, extensive framework that classifies a set of modified gravity models, resulting to cosmological observables that can fit data, and tell us which classes are viable according to observations. Furthermore, I will discuss modified gravity and cosmology models based on Functors of Actions Theories (FAT) which predict actionions, actionic...

195. Alleviating Hubble tension with Torsion Condensation (TorC)

Sinah Legner (University of Cambridge)

Contributed Talk

Persistent cosmological tensions, including the Hubble and [curvature tensions][1], together with the theoretical challenge of unifying General Relativity (GR) with the other fundamental forces in particle theory, motivate the exploration of extensions to the $\Lambda$CDM model.
We investigate the [Torsion Condensation (TorC) model][2], a framework derived from [Poincare Gauge Theory][3] that...

76. An exploration of the NMSSM using deep learning to fit hints of new scalars

Raymundo Ramos (Korea Institute for Advanced Study)

Contributed Talk

In this talk we discuss a recent search over the parameter space of the Next-to-Minimal Supersymmetric Standard Model using deep learning techniques. The particular focus of this search is identifying parameter values that explain hints of excesses around 95 GeV and 650 GeV in Higgs studies, and a discrepancy in Electro-Weakino searches, as well as predicting mono-H and mono-Z signatures of...

149. Asymptotically Cubic Galileon Gravity: Late-Time Departures for Viable Dark Energy

James Hallam (Institute of Cosmology and Gravitation - University of Portsmouth)

Contributed Talk

In this talk, we introduce Asymptotically Cubic Galileon gravity: a luminal Horndeski theory designed to remain close to the cubic Galileon over most of cosmic history, whilst allowing late-time departures that are be broadly consistent with current observations including the recent DESI results. These departures are generated by promoting the coefficients of the Galileon terms to functions of...

137. Axion Detection With Coiled Optical Fibers

Tongxuan Zhang (LMU Munich and Max Planck Institute for Physics)

Poster

We propose a novel interferometric approach to axion searches based on long, coiled optical fibers in an external magnetic field. Considering fiber boundary conditions and bending, I will show that in silica fibers the leading signal is a phase shift of the photon. A key observation is that the axion field will effectively get confined along the fiber, despite no direct interaction between...

49. Axion-dilaton interactions in the dark sector

Adam Smith (University of Sheffield)

Contributed Talk

Axion-dilaton models constitute a well-motivated and minimal class of theories that emerge in extra-dimensional completions of high-energy physics. These models naturally feature kinetic couplings between multiple scalar fields, which can have significant consequences in late-time cosmology. I will present the cosmological implications of these interactions when prescribing an axion and a...

127. Axion-photon conversion in stochastic magnetic fields

Mr Wataru Chiba (Kobe University)

Poster

We study photon-to-axion conversion in stochastic magnetic fields, focusing on the emergence of the nontrivial photon polarizations induced by conversion.
Assuming Gaussian magnetic fields that may possess nonzero helicity, and unpolarized photons as the initial state, we derive expressions for the intensity and linear/circular polarizations of photons after propagation in terms of these...

63. Baryogenesis constraints in $f(T,T_{G})$ modified gravity

S SS

Poster

This work investigates the generation of the observed matter--antimatter asymmetry of the Universe within the framework of $f(T,T_G)$ gravity, where $T$ is the torsion scalar and $T_G$ is its teleparallel Gauss--Bonnet counterpart. In this study, we consider two illustrative modified gravity models, $f(T,T_G)=f(T,T_{G})=\alpha T+\beta\sqrt{T_{G}}$ and $f(T,T_{G})=-T+\delta\;...

68. Beyond 3→2: Towards Realistic SIMP Dark Matter

Halvor Melkild (University of Oslo)

Contributed Talk

Strongly interacting dark sectors with pseudo–Nambu–Goldstone bosons provide a versatile framework for sub-GeV dark matter. While the original SIMP paradigm emphasises number-changing processes as the origin of the relic abundance, the phenomenology of pionic dark matter is considerably richer. Depending on the spectrum and couplings, the relic density can WIMP-annihilations,...

47. Beyond LCDM: Dynamical Dark Energy and High-Redshift Reionization

Hanyu Cheng

Contributed Talk

This talk will explore deviations from the standard cosmological model across cosmic history. First, I will present data analysis results on dynamical dark energy using a novel pressure parametrization and four parameters parametrization testing by the latest datasets. Second, I will discuss model-independent reconstructions of the reionization history using Gaussian processes. We utilize...

125. Beyond the Standard Model investigations at CONUS+

Dario Piani (Max-Planck-Institut für Kernphysik)

Contributed Talk

The detection of coherent elastic neutrino-nucleus scattering (CEνNS) opens up new opportunities for neutrino physics within and beyond the standard model (BSM) of elementary particles. The first detection of CEνNS at nuclear reactors by the CONUS+ experiment allows very valuable tests of BSM scenarios in a low momentum transfer regime. Among them, Non Standard Interactions (NSIs), light...

203. Beyond thermal approximations: Precise cosmological bounds on Axion-Like Particles

Nicola Barbieri (IFIC (CSIC-UV))

Contributed Talk

We derive updated cosmological constraints on light axion-like particles (ALPs) coupled to leptons and photons using a full phase-space treatment of their production in the primordial plasma. The resulting non-thermal phase-space distributions are consistently propagated into calculations of cosmological observables, allowing a precise determination of their impact on $\Delta N_{\rm eff}$....

153. Big Dark Matter in an Era of Big Data

William DeRocco (University of Maryland, College Park)

Contributed Talk

Though dark matter has traditionally been sought in the form of a new, weakly-interacting particle, a viable alternative is that dark matter instead forms macroscopic clumps whose rarity has allowed them to elude detection up until this point. This may change in the coming years with new astronomical facilities allowing us to probe the Universe in ways previously unachievable. In this talk, I...

108. Bounds on Goldstone Dispersion Relations

Warin Patrick McBlain (SISSA)

Poster

Using the analyticity properties of retarded Green's functions, we show that the Goldstone dispersion relations can be written in terms of ‘typically-real functions’: a well-known class of functions in Geometric Function Theory. This identification yields optimal two-sided bounds on Wilson coefficients of higher-derivative operators as explicit functions of the sound speed $c_s$. We test these...

4. Brane-Cosmology

Lakshita Bageja (IISER,B)

Contributed Talk

Holography(AdS/CFT correspondence) has proved to be quite useful in under-
standing field theory at the boundary from the information in the bulk and vice-
versa, the goal is to see if such a prescription can help us understand our universe

and provide a mapping between cosmology and a CFT defined on a manifold with

boundary(BCFT). The bulk geometry is taken to be AdS with an...

103. BULLKID-DM: searching for light dark matter with monolithic arrays of detectors

Leonardo Pesce (Sapienza & INFN Roma 1)

Poster

Authors: L. Pesce on behalf of the collaboration

BULLKID is a novel detector concept based on an array of particle absorbers
sensed by multiplexed Kinetic Inductance Detectors (KIDs). The aim of this
detector is to control the backgrounds by creating a fully active structure and
by applying fiducialization techniques.

Following the encouraging results from a 20 g prototype detector,...

204. Can a JWST-driven reionisation history be consistent with Planck’s optical depth and DESI’s total neutrinos mass constraints?

Enrico Specogna (University of Sheffield)

Contributed Talk

In this talk we will look at a modification to the standard reionization history through the lens of a model for the optical depth ($\tau$) that is motivated by the recent results by JWST, which find sources of ionizing photons at redshifts larger than ever observed before. By using this JWST-driven model, which allows for a “bumpy” reionization history that pushes $\tau$ to higher values as...

85. Casimir Pressure in the Presence of Axion Dark Matter

Ahmad Alachkar (CEA IPHT)

Poster

Axion dark matter can modify electromagnetic phenomena through its coupling to photons, leading to new signatures in precision experiments. In the presence of an external magnetic field, the axion–photon interaction acts as an effective electromagnetic source that generates oscillating fields inside a cavity. Previous work by Brax and Brun showed that this mechanism can produce both classical...

165. Characterizing LHC-Resonances in extended HEFT

David Cabo Almeida (University of Göttingen)

Contributed Talk

In theories with extended scalar sectors, the lightest new scalar could be accessible at colliders. Instead of relying on simplified models, we describe such scenarios in a general and gauge-invariant way using an extended HEFT framework with a nonlinearly realized electroweak symmetry. The structure of the effective operators depends on the $SU(2)$ nature of the scalar in the UV, leading to...

147. Closing in on the EFTofDE with combined probes

Neel Shah (University of Portsmouth)

Contributed Talk

The EFT of Dark Energy (EFTofDE) is a theoretically well-motivated class of modified gravity models, able to explain observational hints for dynamical dark energy with further testable predictions for structure growth and lensing. I will discuss the merits and challenges of combining probes of linear perturbations and present state-of-the-art constraints on the EFTofDE by combining CMB, BAO,...

132. Complementary Direct and Collider Searches for Axions: Dielectric Haloscope Measurements and FCC-ee Phenomenology

Safa Naseem (New York University Abu Dhabi (AE))

Poster

Axions and axion-like particles (ALPs) provide well-motivated solutions to the strong CP problem and constitute compelling dark matter candidates. In this poster, I present complementary strategies for probing axions across a broad mass range using both laboratory-based direct detection and collider phenomenology.

On the direct detection side, I present results from a dielectric haloscope...

28. Constraining cosmology with the Lyman-alpha forest

Olga Garcia Gallego (Institute of Astronomy, University of Cambridge)

Contributed Talk

The Lyman-alpha forest is a powerful cosmological probe of matter density fluctuations in the weakly non-linear regime through the high redshift and underdense intergalactic medium (IGM). The most commonly used statistic to characterize these fluctuations is the 1D flux power spectrum. On small scales, the Lyman-alpha forest traces the properties of dark matter, encoding information on its...

37. Constraining String Effective Actions with Extra-Dimensional Symmetries

María Agustina Pereyra Grau (Universidad de Buenos Aires - Instituto de Astronomía y Física del Espacio)

Contributed Talk

Understanding the symmetry structure of string and supergravity compactifications is a key ingredient in uncovering universal constraints on quantum gravity effective actions. In Kaluza–Klein compactifications, some symmetries of the higher-dimensional theory are preserved in lower dimensions, others are broken, and occasionally symmetry enhancements occur. The symmetries that are enhanced by...

86. Cornered But Alive: GeV-scale Thermal Dark Matter From Dark Photons

David Alonso-González (IFT (UAM-CSIC))

Contributed Talk

GeV-scale thermal dark matter is often considered to be strongly constrained by the null results of direct, indirect, and collider searches. Nevertheless, viable scenarios can still arise in well-motivated dark sector frameworks. In this talk, we explore this possibility in a dark Abelian Higgs model with a Dirac fermion dark matter candidate interacting with the Standard Model through a dark...

60. Cosmic Millicharged Background, Reheating, and Arithmetica Electrōrum

Yu-Dai Tsai (University of California, Irvine)

Poster

I will discuss the cosmic relic background of millicharged particles—hypothetical particles with electric charges much smaller than the electron’s—that may have been produced in the early universe and left an irreducible relic today. I will explain how experimental searches for these particles can provide novel probes of reheating cosmology, the poorly constrained epoch immediately after...

43. Cosmic tensions and interacting dark energy: dynamics and observations

Dr Trupti Patil (Korea Institute for Advanced Study, Seoul, South Korea)

Poster

To address emerging discrepancies among key cosmological parameters, I investigate interacting dark sector models as a possible resolution to the persistent $H_0$ and $S_8$ tensions. I focus on scenarios in which dark matter interacts with quintessence or phantom dark energy.

I will present the background and perturbation equations for the coupled dark matter–dark energy model and discuss...

197. Cosmological signals of dark matter semi-annihilation

Alessia Musumeci (Technical University of Munich)

Contributed Talk

In different classes of models, semi-annihilation of Dark Matter (DM) can set the DM relic abundance. One of the most interesting features of this scenario is the generation of a boosted DM component (BDM), as part of the energy of the initial state is converted into kinetic energy of the DM particle in the final state. In this work, we consider the process $\chi \chi \to \chi^c\,\nu$, which...

151. Cosmological signatures of a solidly unified dark sector

María Pérez Garrote (Universidad de Salamanca)

Contributed Talk

I will present a cosmological model with a unified solid dark sector that transits from a CDM phase at high redshift to a quasi-de Sitter phase at late times. Remarkably, this can be accomplished without generating strong acoustic oscillations, thus being compatible with observations of the matter power spectrum. The solid unified dark sector can reduce the rate of matter clustering in the...

95. CPT-Symmetric K"ahler-Dirac Fermions: Implication of the Standard Model and Cosmology

Wei-Ning Deng (Astrophysics Group, Cavendish Laboratory, Cambridge)

Poster

The CPT-Symmetric Universe model provides elegant solutions to major cosmological puzzles—including dark matter, the cosmological constant problem, and the universe's flatness puzzle—by positing that the Big Bang acts as a CPT mirror. However, the theoretical reason why the universe requires this mirror has remained an open question.

In this talk, we propose that the answer lies in the...

188. Dark Energy Survey Year 6: Cosmological Results and Lensing Ratios

Gisela Cristina Camacho Ciurana (ICE-CSIC)

Contributed Talk

Increasingly precise observations are beginning to expose potential cracks in the standard cosmological model, from the Hubble constant tension to emerging hints of evolving dark energy. Resolving whether these point to new physics, and uncovering the nature of dark matter and dark energy, requires precise measurements of cosmic geometry and the growth of structure. The Dark Energy Survey...

40. Dark Matter Searches at PICO

Dr Mayank Tripathi (mtripathi@uchicago.edu)

Contributed Talk

The PICO collaboration operates bubble chambers to search for WIMP dark matter, leveraging the excellent gamma rejection and long live fractions enabled by operating at a lower degree of superheat than the bubble chambers of the 1960s. This advancement allows for significantly improved background rejection while maintaining sensitivity to nuclear recoils. Located at the SNOLAB underground...

163. Dark sector genesis in the EFT Framework

Ananya Tapadar (Henryk niewodniczanski institute of nuclear physics of the polish academy of sciences)

Poster

We explore a non-minimal secluded dark sector (DS) within an effective field theory (EFT) framework. We consider a suitable extension of the type-X Two Higgs Doublet Model (2HDM) as the ultraviolet origin of the secluded dark sector. The DS consists of a dark matter (DM) candidate and a mediator particle $a$. It is non-thermally populated through various dimension-6 four-fermion operators,...

89. Detecting black hole microstates

William Chan (University of Pennsylvania)

Contributed Talk

A step towards probing the black hole interior and its structure is being able to detect the black hole microstate. We demonstrate that the Euclidean two-point function of an appropriately chosen probe operator can detect the microstate of an asymptotically AdS black hole. This detection, which requires a tuned, state-dependent choice of probe, is the result of a new gravitational saddle,...

83. Discovering New Particles with Cosmic Microwave Background

Anish Ghoshal (University of Warsaw, Poland)

Contributed Talk

Cosmological collider signals of primordial non-Gaussianity arise at tree level when a particle has Hubble mass during inflation. We critically review the formalism finding that a large class of inflationary theories, based on Planck-scale physics, predict a scalar bi-spectrum around the gravitational floor level. This mild signal arises for example in R2 gravity, in the regime where its...

156. Disentangling cosmic distance tensions with early and late dark energy

Tanisha Jhaveri (University of Chicago)

Contributed Talk

Recent cosmological data reveal tension between parameters inferred from measurements of the cosmic microwave background (CMB), baryon acoustic oscillations (BAO), and supernovae (SN) under $\Lambda$CDM. Typical dynamical dark energy parameterizations (such as $w_0w_a$) that seek to jointly resolve these tensions have an equation of state parameter that crosses into the phantom regime, leading...

185. DMRadio: A lumped-element, low-mass axion search

Andrew Yi (SLAC National Accelerator Laboratory)

Contributed Talk

The QCD axion is a particle that has been postulated to be a solution to the strong CP problem and also a candidate for dark matter in the universe. The DMRadio suite of experiments is a resonant, lumped-element search that probes low mass axions below 1 $\mu$eV. To achieve the necessary sensitivities, the development of DMRadio involves high-field DC magnets of various geometries, tunable...

171. Domain Walls in the 2HDM

Adam Thomasson (The University of Manchester)

Poster

Topological defects arising from cosmological phase transitions provide a direct link between early-Universe cosmology and particle physics. The two-Higgs-doublet model (2HDM) exhibits a rich vacuum structure, admitting a variety of topological defects including domain walls, strings and monopoles. A $\mathbb{Z}_2$ symmetry is often imposed to eliminate flavour-changing-neutral-currents...

55. Dynamical System Analysis of Renyi Holographic Dark Energy

Dr Santanu Das (Institute of Engineering & Management, University of Engineering and Management)

Poster

Recent cosmological observations confirm that the universe is undergoing a late-time accelerated expansion. To account for this phenomenon, an exotic component with negative pressure, known as dark energy, has been proposed. Among various dark energy models, the Holographic Dark Energy (HDE) model, motivated by the holographic principle of quantum gravity, has gained significant attention.
In...

92. Dynamical systems analysis in Newer GR cosmology

Ms Vasiliki Karanasou (University of Tartu)

Poster

In this presentation, we explore the rich cosmological dynamics of a symmetric teleparallel theory, the so-called Newer General Relativity (Newer GR) for a flat FLRW metric. We begin by introducing the fundamental concepts of non-metricity-based theories and Newer GR cosmology. We focus on two physically motivated one-parameter subclasses of theories for which the post-Newtonian parameters are...

93. Effective Field Theory Constraints on Scalar Extensions of the Standard Model

Muhammad Farhan (University of Bologna, Italy)

Poster

Extensions of the Standard Model involving additional scalar degrees of freedom arise in a wide range of beyond-Standard-Model (BSM) scenarios, including dark matter models and mechanisms addressing electroweak naturalness. In this work, we investigate such scalar extensions within an effective field theory (EFT) framework, with emphasis on higher-dimensional operators and their...

102. Electro-Weak Phase Transitions and Collider Signals in the Aligned 2-Higgs Doublet Model

Atri Dey

Poster

We show that the Aligned 2-Higgs Doublet Model (A2HDM) is a framework able to
simultaneously accommodate strong first-order electroweak phase transitions, in turn generating
detectable Gravitational Waves, as well as a variety of Standard Model-like Higgs boson signals
accessible at the Large Hadron Collider (LHC). We map the corresponding expanse of parameter space where such a...

29. Enabling Forbidden Dark Matter from a First-Order Phase Transition

Mr Partha Kumar Paul (Indian Institute of Technology Hyderabad)

Poster

We propose a minimal and testable framework for light fermion dark matter in the MeV–GeV mass range, charged under a dark $U(1)_D$ gauge symmetry that is spontaneously broken by a scalar field. The resulting dark-sector phase transition induces a mass gap that activates a forbidden annihilation channel into slightly heavier dark states, thereby setting the dark matter relic abundance while...

52. Evaporating black holes: how the burden of their memory stabilizes them

Michael Zantedeschi

Contributed Talk

The memory burden effect describes how an object's stored information resists its own decay. This mechanism is especially pronounced in saturons—systems that saturate unitarity bounds on entropy—with black holes providing the prime example. I will show how memory burden can halt Hawking evaporation and dynamically stabilize black holes against complete decay. Crucially, this phenomenon is not...

169. Filtered dark matter from strong first order phase transitions

Satumaaria Sukuvaara

Contributed Talk

While cooling down, the early universe is believed to have undergone symmetry breaking phase transitions. One attractive possibility for extending the Standard Model is that these phase transitions are of the first order, as they might be able to produce observable gravitational waves. We consider a dark matter freeze-out mechanism, filtering, where dark matter particles become massive in a...

123. Flipped rotating axion: Baryogenesis and Dark Matter

Prof. Konstantinos Dimopoulos (Lancaster University)

Contributed Talk

It is shown that the co-genesis of baryon asymmetry and dark matter can be achieved through the rotation of a spectator axion-like particle, because of a flip in the vacuum manifold’s orientation at the end of inflation. This can occur if the axion has a periodic non-minimal coupling to gravity (while preserving the discrete shift symmetry) in non-oscillating inflation models, where the...

65. Forecasting constraints on non-thermal LiMRs from future CMB experiments (CMB-S4/Simons Observatory)

Abhik Bhattacharjee (Harish-Chandra Research Institute (HRI))

Poster

Precise measurements of the cosmological impact of dark sector relics can shed light on Physics beyond the Standard Model. In this work, we present Fisher forecasts on \textit{non-thermal LiMR} models for a CMB Stage IV-like experiment and the Simons Observatory---particularly focusing on a model of inflaton/moduli decay giving rise to non-thermally distributed dark sector particles, and also...

160. Freeze-in from feeble to stronger coupling: cosmology and experimental signatures

Thomas REGGIO (Laboratoire de Physique de Clermont Auvergne)

Poster

The freeze-in mechanism is an alternative to standard thermal freeze-out for cosmic dark matter production.

Freeze-in predictions can be sensitive to the initial temperature at the onset of the radiation domination era (reheating temperature) which, in most computations, is taken to be (effectively) infinite.

I will discuss dark matter freeze-in in a scenario where the reheating...

187. From CUORE to CUPID: Toward a Next Generation Search for Neutrinoless Double Beta Decay

Elena Ferri

Contributed Talk

The search for neutrinoless double beta decay (0νββ) is fundamental for investigating lepton-number violation, probing new physics beyond the Standard Model, and determining whether neutrinos are Majorana particles. CUORE, a cryogenic calorimetric experiment at LNGS, studies 0νββ in $^{130}$Te using 988 TeO₂ crystals, reaching a tonne-scale mass and operating below 15 mK. Since 2017, CUORE has...

214. From Distance Ladder to Network: Methods, Code, and Results from H0DN

Emre Ozulker

Contributed Talk

The H0 Distance Network (H0DN) combines multiple distance indicators (Cepheids, TRGB, SNe Ia, SBF, megamasers, and others) into a single covariance-aware linear system to determine the Hubble constant. The baseline analysis yields H0 = 73.50 +/- 0.81 km/s/Mpc (1.09% precision, 7.1-sigma tension with early universe based inferences that assume LCDM) and demonstrates robust stability across more...

193. From real-time simulations to experimental probes of vacuum decay

Emilie Hertig (University of Cambridge)

Poster

False vacuum decay (FVD) plays a central role in early-Universe cosmology, with implications for inflationary dynamics, baryogenesis, and Higgs stability. While this type of first-order phase transition is traditionally described using Euclidean instanton methods, the recent development of semiclassical lattice simulations has enabled us to model the decay process in real time.
In this talk,...

7. Gauge invariant perturbations of F(T,T_G) Cosmology

Prof. Bivudutta Mishra (BITS-Pilani, Hyderabad Campus)

Contributed Talk

The Gauss-Bonnet invariant connects foundational aspects of geometry with physical phenomena in a variety of ways. Teleparallel gravity offers a novel direction in which to use the Gauss-Bonnet invariant to go beyond standard cosmology. In this work, we explore the cosmological perturbations of teleparallel gravity generalized through the Gauss-Bonnet invariant. This is crucial in...

139. General relativity as diffusive equilibrium of scalar-tensor gravity

Sotirios Karamitsos (University of Tartu)

Contributed Talk

Scalar-tensor theories of gravity are known to generically admit an effective imperfect fluid description, which leads to a natural interpretation of GR as a state of thermal equilibrium. In particular, it is possible to assign a temperature to nonminimally coupled fields, which increases as the theory deviates from GR. However, this temperature is conformally dependent, and can be arbitrarily...

18. Generalised anomalies, QCD, and holography

Mohammad Akhond

Contributed Talk

During the last decade, the notion of an 't Hooft anomaly has
been generalised to the case of discrete symmetries. An interesting
instance, discussed by Tanizaki, is the mixed anomaly between the
discrete axial symmetry and the flavour and baryonic symmetries in
massless QCD. The goal of this talk is to provide a derivation of this
anomaly from a top-down holographic dual of QCD. I will...

10. Generalized Entropic Cosmology

Simone D'Onofrio (ICE - CSIC)

Poster

The thermodynamics of black holes inspired the concept of black hole entropy, linking gravity and thermodynamics. When applied to cosmology, this leads to the standard Friedmann equations, which face challenges in explaining the universe’s evolution. Modified entropies have been proposed to resolve these issues. A recently introduced four-parameter generalized entropy unifies several known...

207. Global Analysis of Linear Standard Model Extensions at HL-LHC and FCC-ee

Victor Maura Breick (King's College London)

Contributed Talk

Linear Standard Model Extensions (LSMEs) are a motivated set of simplified models for exploring the phenomenology of physics beyond the Standard Model (BSM) and assessing the reach of future colliders. They capture a wide range of BSM physics: any particle coupling linearly to the Standard Model (SM) with relevant or marginal interactions is an LSME. Examples include vector-like fermions, new...

62. Global Extraction of the Nuclear Electromagnetic Response Functions of C-12, Ca-40 and Fe-56 and Comparisons to the Predictions of the SuSAv2 Superscaling Formalism for Electron and Neutrino Scattering

Arie Bodek (University of Rochester (US))

Contributed Talk

We perform a global extraction of the ${\rm ^{12}C}$, ${\rm ^{40}Ca}$ and ${\rm ^{56}Fe}$ longitudinal (${\cal R}_L$) and transverse (${\cal R}_T$) nuclear electromagnetic response functions from an analysis of all available electron scattering data on carbon. The response functions are extracted for energy transfer $\nu$, spanning the nuclear excitation, quasielastic (QE), resonance...

24. Gravitational wave signatures of dark sector portal leptogenesis

Dr. Devabrat Mahanta

Contributed Talk

We study the possibility of probing leptogenesis via stochastic gravitational waves (GW) arising from a dark sector assisted first-order electroweak phase transition. The same dark sector, with non-trivial transformation under an unbroken $Z_2$ symmetry is also responsible for providing the only source of CP asymmetry via one-loop interference with the tree level decay of a heavy right-handed...

141. Gravitational waves induced from the symmetry restoration of a Higgs phase of gravity

Roxane Theriault (Jagiellonian University)

Poster

We study the gravitational waves induced by a scalar field undergoing ghost condensation---an analog of the Higgs mechanism in gravity---as it transitions to a canonical scalar field. The presence of this ghost condensate leads to an early matter-dominated era which transforms into a radiation-dominated era when the symmetry is restored. As a result, the production of induced gravitational...

155. Gravothermal evolution of dissipative self-interacting dark matter halos

Ludwig Schmidt (Technical University of Munich)

Contributed Talk

Many proposed self-interacting dark matter (SIDM) models give rise to radiative processes that can dissipate energy from dark matter halos. We present the first extension of the N-body formalism for frequent small-angle self-interactions (fSIDM) that includes effective dissipation.
We find that dissipation qualitatively changes the gravothermal evolution of SIDM halos beyond simply...

124. Heavy dark matter in rapidly evolving massive stars

Giorgio Busoni (Adelaide University)

Contributed Talk

Dark matter (DM) constitutes most of the matter content of the Universe, yet its particle nature remains unknown. While laboratory searches and cosmological probes have placed strong constraints on many candidate models, astrophysical environments provide a complementary avenue to test DM interactions under extreme conditions. Stars are particularly promising laboratories: as they move through...

167. Hiding new physics in the IR

Peter William Millington (The University of Manchester)

Poster

Dark matter and dark energy are problems of large, astrophysical and cosmological scales. Taking the perspective that these problems may therefore require us to introduce new physics in the infra red, we will argue in the case of additional spin-zero degrees of freedom that this invariably leads to scalar-tensor theories of gravity. Such low-mass physics must be able to evade existing tests of...

136. Higgs boson production and decay rate measurements with the ATLAS experiment

Ahmed MARKHOOS

Contributed Talk

With the Run 2 and Run 3 pp collision dataset collected by the ATLAS experiment at LHC, very precise measurements of Higgs boson production and decay rates can be performed, shedding light over the electroweak symmetry breaking mechanism. This talk presents the latest precise measurements of Higgs boson productions and decays, including fiducial, differential, as well as Simplified Template...

215. Higgs Criticality: Electroweak Vacuum Metastability as a Window to Beyond the Standard Model Physics

Maximilian Detering (King's College London)

Contributed Talk

This work proposes a direct link between the hierarchy problem and Weakly Interacting Massive Particles (WIMPs): we suggest that the small mass of the Higgs boson arises from being dynamically driven to the scale of the WIMP. Such a special electroweak vacuum is singled out by lying close to the critical boundary of a phase transition, as recently explored in a new class of cosmological...

12. Higher order curvature, Coupling, and the Strange Companion of GW190814

Mr DEBADRI BHATTACHARJEE (COOCH BEHAR PANCHANAN BARMA UNIVERSITY)

Poster

We investigate the maximum mass of strange quark stars within the framework of quadratic curvature gravity incorporating a non-minimal matter-geometry coupling. The coupling parameters associated with the quadratic curvature term and the matter-geometry interaction quantify, respectively, the contributions from higher-order curvature corrections and the departure from minimal coupling. We show...

73. How safe is supernovae data?

Paul Shah (UCL)

Contributed Talk

The tantalising hint of evidence for dark energy evolution depends on the interplay of data from the cosmic microwave background, baryon acoustic oscillations and Type Ia supernovae. Two recent supernovae data releases, DES-Dovekie and Union3.1, have reduced the preference for evolution compared to previous versions. What has changed? And can the data be trusted?

96. How Sensitive is Cosmic Inflation to Quantum Corrections?

Lucien Heurtier (King's College London)

Contributed Talk

In this talk, I will present a non-perturbative framework that allows to track the dynamics of slow-roll inflation while consistently incorporating quantum corrections, based on an alternative functional renormalisation group (RG) approach. I will guide you through the derivation of a set of coupled Friedmann-RG flow equations governing the joint evolution of spacetime, the inflaton field, and...

23. Implications of Modular $A_4$ Group on Left-Right Symmetric Inverse Seesaw Model

Raktima Kalita

Contributed Talk

In this work, we have incorporated $A_4$ modular symmetry into the left-right symmetric inverse seesaw model. By restricting the proliferation of flavon fields, such modular symmetry can improve the predictability of the model. In this scenario, two right-handed neutrinos and three sterile fermions are added to the standard model, resulting in three light active neutrino states and a light...

191. Improved Big Bang Nucleosynthesis constraints on decaying massive relics

Jonas Frerick (Sapienza University Rome)

Poster

In this presentation, I will discuss big bang nucleosynthesis bounds on relics in the early Universe which decay into pairs of SM particles. Due to final-state radiation, these SM particles will emit other SM particles, and in particular quarks and gluons will hadronize. The final products of these showers then participate in different types of interactions with the baryons in the early...

198. Improved cosmological constraints on axion-lepton interactions

Adam Gomułka (University of Warsaw, Faculty of Physics)

Poster

We investigate lepton-flavour-conserving (LFC) and lepton-flavour-violating (LFV) axion-lepton couplings using cosmological data, addressing the specific mass ranges where the standard $\Delta N_\mathrm{eff}$ approximation fails. We implement a full phase-space treatment of thermal axion production and incorporate finite axion mass effects to test these couplings against Planck 2018 CMB and...

30. Interacting dark energy with dark matter entropy couplings

Elsa Teixeira (Laboratoire Univers et Particules de Montpellier, University of Montpellier)

Contributed Talk

The persistent discrepancies between predictions of the standard cosmological model and high-precision measurements across multiple probes remain a significant challenge in modern cosmology. Over the past decade, mounting evidence for tensions in key cosmological parameters - derived through both model-dependent and independent methods - has motivated the exploration of extensions to the...

212. KATRIN++: Towards a next-generation neutrino mass experiment using tritium beta decay

Svenja Heyns (Karlsruhe Institute of Technology)

Contributed Talk

After completing 1000 days of data taking at the KATRIN experiment, the collaboration expects to reach a final sensitivity on the effective anti-electron neutrino mass below 300 meV. However, neutrino oscillation observations allow the value to be as low as 50 meV or 9 meV, depending on the neutrino mass ordering. Taking the next step in direct neutrino-mass searches includes probing the...

194. Large Primordial Fluctuations: Stochastic vs. Classical $\delta N$ approaches

Parth Bhargava (ICG, Portsmouth)

Contributed Talk

The classical evolution of fields during a period of accelerated expansion in the very early universe ("inflation") can establish an idealised homogeneous and isotropic cosmology. However, quantum fluctuations inevitably generate inhomogeneities and anisotropies on all observable scales and beyond. The $\delta N$ formalism provides a powerful framework to describe the nonlinear curvature...

17. Late time behavior in f(R,Lm) gravity through Gaussian reconstruction and dynamical stability

Yengkhom Kalpana Devi (Bits Pilani Hyderabad Campus)

Contributed Talk

In this paper, we explore modified gravity in the framework of $f(R, \mathcal{L}_m)$ theory by reconstructing the function $G(\mathcal{L}_m)$, where $\mathcal{L}_m = \rho$ be the matter Lagrangian, under the assumption of a pressureless, matter-dominated Universe. Using a non-parametric Gaussian process reconstruction technique applied to Hubble data, we present two cosmological models with...

119. Limits on total lepton number and lepton flavour asymmetries from BBN and the CMB

Mario Fernandez Navarro (University of Zurich)

Contributed Talk

In this talk, I will discuss the impact of lepton flavour asymmetries on BBN and the CMB. I will show that solving the momentum averaged quantum kinetic equations describing neutrino oscillations and interactions is an accurate approximation to the full momentum-dependent system. Our formalism allow us to study the scenario of total vanishing lepton number, revealing a rich flavour structure...

201. Linking Leptogenesis and Asymmetric Dark Matter

Henry McKenna (University of Liverpool)

Poster

We investigate a minimal extension of the Leptogenesis framework that simultaneously explains the observed baryon asymmetry and dark matter (DM) abundance through the decay of a heavy Majorana neutrino. In this scenario, CP violation arises from complex Yukawa couplings, enabling the generation of asymmetries in both the Standard Model (SM) and DM sectors. We explore two regimes: (i) wash-in,...

164. Listening for Right-Handed Neutrinos in Gravitational-Wave Backgrounds

Angus Spalding (Univeristy of Southampton)

Contributed Talk

I will show that spectral features of a gravitational-wave background can probe type-I seesaw parameters, independently of the gravitational-wave production mechanism. Long-lived Right-Handed Neutrinos generically induce a temporary period of early matter domination in the thermal history of the Universe, which imprints a feature in any primordial gravitational-wave background, characterised...

69. Low-Energy Neutrino Predictions from SO(10)-Inspired Leptogenesis

Xubin Hu (University of Southampton)

Contributed Talk

We discuss neutrino mass generation and Leptogenesis in GUT-motivated type-I seesaw models, focusing on the connection between matter-antimatter asymmetry and measurable low-energy neutrino parameters. Building on our study of flavour coupling, we show that spectator-induced effects can significantly reshape the viable regions in the space of the lightest neutrino mass, the Dirac CP phase, the...

211. Magnetic monopole plasma oscillations and implications for TeV Blazars

Mariia Khelashvili (SISSA)

Poster

Magnetic monopoles arise in many beyond Standard Model scenarios. When placed in an astrophysical magnetic field, monopoles induce a magnetic analogue of plasma oscillations. In this work, we explore monopole-induced oscillations of the intergalactic magnetic field (IGMF). We show that these oscillations lead to collimation of electrically charged particle trajectories, reducing their usual...

148. Measuring the neutron Electric Dipole Moment for CP-violation searches beyond the standard model.

Katia MICHIELSEN (LPSC, Grenoble)

Contributed Talk

The n2EDM experiment aims to measure the neutron Electric Dipole Moment (EDM) with an unprecedented precision of $10^{-27} \, e$ cm.
The EDM is the interaction between the neutron spin and an external electric field. It is measured via precession frequency measurements on stored ultracold neutrons.
A better measurement of the nEDM probes CP-violation Beyond the Standard Model and allows...

45. Model-independent tests of gravity with the Weyl potential evolution

Nastassia Grimm (University of Portsmouth)

Contributed Talk

Cosmological observations are well described by the LCDM model, a universe with a cold dark matter component and a cosmological constant acting as dark energy. However, more and more cosmological tensions have emerged in the past decades, putting this simple model into question. A large amount of research has focused on the quest for an alternative model of modified gravity and dark energy,...

206. Modified gravity & friends vs current CMB data.

Enrico Specogna (University of Sheffield)

Contributed Talk

In this talk we will look at the evidence of the effects induced by seemingly different extensions to the standard cosmological model in the cosmic microwave background (CMB) primary and secondary anisotropies: modified gravity (through the growth index - '$\gamma$', a modification of the growth of linear perturbations in the standard model, and the '$\mu-\Sigma$' framework, a modification of...

54. Modular and CP invariant SU(5) with a single adjoint

Marco Carducci (Romatre university (INFN))

Contributed Talk

We consider a modular-invariant SU(5) model supplemented, for the first time, by a spontaneously broken generalized CP symmetry. Therefore, CP violation originates solely from the vacuum expectation value of the modulus, whose real component acts as the unique source of CP breaking. In the lepton sector, neutrino masses are generated via a type I+III seesaw mechanism, thanks to a single...

82. Modular quintessence and de-Sitter in heterotic orbifolds

Hansel Gordillo Ruiz (UNAM, Mexico)

Contributed Talk

Recent results from DESI indicate that the accelerated expansion of the Universe may not be fully explained by a simple cosmological constant and instead may point toward a dynamical form of dark energy. At the same time, modular symmetries are emerging as important ingredients in string theory, as modular invariance is naturally built into many string compactifications. In this work, we...

100. Neutrino decays in light of the neutrino mass tension

Dr Guillermo Franco Abellán (IFIC, CSIC - University of Valencia)

Contributed Talk

A new tension is starting to emerge between the tight cosmological upper bounds on the total neutrino mass and the lower limits from oscillation data, with potentially far-reaching implications for cosmology and particle physics. Invisible neutrino decays provide a compelling particle physics scenario to understand such measurements. In this talk, I will present updated limits on a framework...

109. Neutrino flavour conversion in the early universe

Julien Froustey (IFIC (CSIC-UV))

Contributed Talk

Neutrinos play a pivotal role in the early Universe, as their evolution and decoupling set the conditions for Big Bang Nucleosynthesis (BBN) and influence subsequent cosmological epochs. In this talk, I will focus on the effects of neutrino flavour conversion before and during the decoupling epoch, and their implications across different contexts.

While flavour oscillations have only minor...

210. No room for monopole dark matter

Théodore Fischer (LUPM)

Contributed Talk

The magnetic monopole of a dark sector has been advocated as an appealing dark matter candidate, since its stability naturally follows from topological arguments. I will revisit the computation of the monopole abundance generated by a thermal phase transition, exploring the three regimes where the phase transition is second order, weakly first order, or supercooled. This will allow us to...

77. Non-Adiabatic Mixing in Density Matrix Formalism

Shreya Girishkumar Pandit (University of Southampton)

Contributed Talk

Description of quantum coupling is a universal problem appearing in many different fields (NMR, quantum computing, molecular and atomic physics,...). In particle physics, it applies to particle mixing, underlying neutrino oscillations and resonant particle production (applicable beyond these two) in different environments, of great importance in many BSM scenarios. I will discuss non-adiabatic...

36. Non-Gaussian statistics to break degeneracies in modified gravity

Alessandro Vadala (INAF - Astronomical Observatory of Rome)

Contributed Talk

The characterization of the statistical properties of the cosmological density field represents a central topic in today's cosmology. Understanding the distribution of matter in the Universe provides a powerful means of testing the standard cosmological model and identifying possible deviations. Among the available probes to characterize the statistical properties of the cosmological density...

180. Non-Linear Effects of the Interacting Dark Energy Model

Yuejia Zhai (University of Sheffield)

Contributed Talk

We focused on a phenomenological interacting dark energy model (IDE) with energy-momentum transfer from dark matter to dark energy through a coupling $Q = ξ\mathcal{H}ρ_{DE}$. Following our previous work on constraining the parameters of the same IDE model using CMB and DESI data, we now present the N-body simulation results based on a modified version of RAMSES code. Compared with the...

150. Nonlinear Relativistic Effects in the Observable Redshift Drift

Giuseppe Fanizza (LUM University)

Poster

In this talk, I will present the full expression for the redshift-drift at second-order in perturbation theory, corroborate its validity by explicitly showing its gauge-invariance for both the observer and source terms, and discuss its validity also for cosmological models beyond LambdaCDM. Afterwards, I will discuss the geometrical hierarchy of the leading terms at leading and next-to-leading...

91. Novel bounds on neutrino portal dark matter from leptonic meson decays

Yuji Omura (Kindai University)

Poster

We investigate the potential of leptonic meson decays M→ℓν, where M is a pseudo-scalar meson, as a probe of neutrino portal dark matter. The model of our focus features a neutral fermion ψ and scalar ϕ, which are coupled predominantly to neutrinos in Yukawa couplings. This interaction generates two corrections to the M→ℓν observables. The first one is a novel three-body decay process M→ℓψϕ....

166. Numerical Relativity in effective field theories of gravity

Llibert Aresté Saló

Contributed Talk

I will discuss how Numerical Relativity can serve as a tool to study non-linear dynamics in effective field theories (EFTs) of gravity. I will first present our work on scalar-Gauss-Bonnet gravity, in which a change of gauge enables well-posed evolutions in black hole spacetimes, which reveal potential smoking gun signatures in gravitational-wave emission. I will then introduce a recently...

157. Observational prospects of axion inflation

Oksana Iarygina (Nordita)

Contributed Talk

Axions are well-motivated pseudoscalar fields that arise in many extensions of the Standard Model and can drive inflation. In scenarios where an axion couples to a gauge sector during inflation, the rolling field can lead to exponential amplification of gauge-field fluctuations, with important implications for particle production, reheating dynamics, primordial gravitational wave signatures,...

98. Optimized numerical evolution of perturbations across sharp background trajectory turns in multifield inflation

Guillermo Fernando Quispe Peña (Simon Fraser University)

Contributed Talk

Features in the primordial power spectrum require numerical methods that are both accurate and scalable across the wide class of multifield inflationary models that produce them. Sharp turns in the background trajectories, induced by either potential or geometric effects, render these computations particularly challenging. In this work, we introduce an efficient method for evolving primordial...

58. Origin of cosmological neutrino mass bounds: background versus perturbations

Rasmi Hajjar (CCAPP - Ohio State University)

Contributed Talk

In this talk, I will address the emerging anomaly between cosmological and oscillation constraints on the sum of neutrino masses. I will review the main implications of neutrino masses at both the background and perturbations levels, discussing the primary neutrino effects to which CMB data is sensitive, and finding valuable hints to evade cosmological bounds. Our findings show that the CMB...

48. Particle physics models of interacting bosonic dark energy and fermionic dark matter in Einstein scalar Gauss-Bonnet gravity

Simran Arora

Poster

We explore a cosmological framework in which a Gauss-Bonnet (GB) coupled scalar field, acting as dark energy, interacts with a fermionic dark matter field through a coupling obtained from the point of view of particle physics. This setup is inspired by string/M-theory, and two representative scalar field potentials are investigated: exponential and power-law. A distinctive feature of the...

59. Post-Inflationary Higgs Dynamics from Spacetime Curvature

Dr JAVIER RUBIO (Universidad Complutense de Madrid)

Contributed Talk

The Standard Model Higgs field, when non-minimally coupled to gravity, can display rich dynamics after inflation. In cosmological setups that include a short kination stage, the fast variation of spacetime curvature can temporarily destabilize the electroweak vacuum through curvature-induced tachyonic effects. This process can trigger a gravitationally sourced phase transition, leading to the...

145. Precision gravitational wave theory at seventh post-Newtonian order

Matteo Pegorin (University of Padova & INFN Padova)

Poster

Next generation gravitational wave observatories, such as the Einstein Telescope and LISA, will require an improvement of up to two orders of magnitude in waveform model accuracy to control theoretical systematics in precision parameter estimation. In particular, robust inference of cosmological parameters and future null tests of general relativity require highly accurate predictions within...

61. Precision Measurement of the Electroweak Mixing Angle in the Region of the Z pole

Arie Bodek (University of Rochester (US))

Contributed Talk

This contribution presents an overview of an improved extraction of the effective leptonic weak mixing angle, $\sin^2θ^ℓ_{eff}$, based on the published CMS measurement of the forward-backward asymmetry in Drell-Yan events at 13 TeV. While the original CMS analysis achieved a significant reduction in experimental uncertainties, its overall precision remains limited by residual uncertainties in...

181. Preparedness for Dark Matter Discovery at SuperCDMS SNOLAB

Junwen Xiong (Caltech)

Contributed Talk

The SuperCDMS SNOLAB experiment is currently being commissioned at the Canadian underground facility SNOLAB. The experiment uses four detector towers that contain 24 detectors in total, including both interleaved Z-dependent Ionization and Phonon (iZIP) and high-voltage (HV) detectors with germanium (Ge) and silicon (Si) targets. The iZIP detectors measure both charge and phonon signals and...

112. Primordial Black Hole Formation from Inflationary Higgs Instability

Ethan Milligan (QMUL)

Contributed Talk

Metastability of the Standard Model Higgs during inflation raises the possibility that stochastic fluctuations push the field beyond the instability barrier and into a region of negative energy vacuum. Whether such excursions are fatal to our Universe depends on their fully nonlinear gravitational evolution. We revisit this problem using numerical simulations of a spherically symmetric...

178. Primordial Power Spectrum from a deformed Bouncing background

Gabriele Barca (University of the Basque Country)

Contributed Talk

We present the formalism of Deformed Commutation Relations, consisting in a modification of the standard Heisenberg commutator (or of the Poisson brackets in the semiclassical limit) inspired by the Generalised Uncertainty Principle representation, and its implementation to the cosmological Friedmann-Lemaitre-Robertson-Walker isotropic model. One specific form had previously been shown to...

20. Probing Cosmic Ray Composition and Muon-philic Dark Matter using GeV Muon sources

Qiang Li (Peking University (CN))

Poster

We propose here a set of new proposals and some preliminary experimental results involving probing and knocking with muons (PKMu). There is a wealth of rich physics to explore with GeV muon beams either from dedicated beam or cosmic source. Examples include but not limited to: muon scattering can occur at large angles, providing evidence of potential muon-philic dark matter or dark mediator...

205. Probing gluon saturation in a DIS process via nonconformal soft-wall holography

Adrita Chakraborty (AGH University of Science and Technology)

Contributed Talk

We model a soft-wall type nonconformal holography to study the gluon saturation phenomena occuring in a deep inelastic scattering process. The gravity background has been considered as a nonconformal warped version of 5D AdS geometry. The warpedness is characterized by a deformation parameter with finite length dimension. To represent a highly boosted target nucleus, we introduce a...

173. Probing neutrino dark matter interactions at neutrino detectors

Salvador ROSAURO-ALCARAZ (LPCA - CNRS)

Contributed Talk

We study the possibility that dark matter primarily interacts with the SM through neutrinos, and the prospects for detection in neutrino detectors. In particular, we analyze the DSNB searches at Super-Kamiokande in terms of such a neutrino-dark matter interaction.

110. Probing the neutrino chemical potential with cosmological observations

Pietro Ghedini (IFIC, CSIC - UV)

Contributed Talk

The electron neutrino degeneracy parameter, $\xi_{\nu_\mathrm{e}} = \mu_{\nu_\mathrm{e}} / T$, is tightly constrained by Big Bang Nucleosynthesis (BBN), while the degeneracy parameters of the other neutrino species, $\xi_{\nu_\mathrm{x}}$, remain weakly constrained by cosmological observations alone. In this talk, we present constraints on $\xi_{\nu_\mathrm{e}}$ and $\xi_{\nu_\mathrm{x}}$...

128. Production and Validation of Photosensors for Time Projection Chamber of the DarkSide-20k Dark Matter Experiment

Camilla Salerno (Istituto Nazionale di Fisica Nucleare)

Poster

The DarkSide-20k is a next-generation dark matter experiment aiming at a direct detection of Weakly Interacting Massive Particles (WIMPs) via nuclear recoils in liquid argon. The detector, currently under construction at the Gran Sasso National Laboratory (LNGS), Italy, will benefit from the natural shielding against cosmic rays provided by the lab’s underground location. It will employ a...

121. Quantum Entanglement Is Quantum: Insights from Diboson Systems at the LHC

AJAY Kaladharan

Contributed Talk

Polarisation and spin correlations in diboson systems are powerful probes for precision tests of the Standard Model and searches for new physics. More recently, viewing these observables through the lens of quantum information, such as assessing whether diboson systems exhibit quantum entanglement, has opened a compelling new frontier in these investigations. They also provide a unique...

42. Quantum fields in boson star spacetime

Qi-Xin Xie (University of Nottingham)

Poster

Boson stars are appealing dark matter candidates and black hole mimickers. They have been extensively studied in classical gravity, but their quantum properties remain comparatively unexplored. We compute the quantum scalar fields and stress tensor in boson star spacetimes within the framework of semiclassical gravity. Divergences are regularized using Pauli-Villars fields, and accurate...

41. Quark and lepton mixing in the Asymptotic Safe Standard Model

Zois Gyftopoulos (Heidelberg University)

Poster

In this talk, I will explore the phenomenological consequences of Quantum Scale symmetry in the matter sector of the Standard Model with Asymptotically Safe Quantum Gravity. In particular, trans-Planckian quantum scale symmetry in the matter sector induced by Asymptotically Safe Quantum Gravity, leaves an imprint on some of the Standard Model parameters, namely the CKM mixing elements. We...

53. Quark hierarchies and spontaneous CP violation from Siegel modular forms

Matteo Parriciatu (Università Roma Tre)

Contributed Talk

We consider a new flavour framework in which quark mass hierarchies naturally arise from a small departure of the modulus VEV from special stabilised regions of genus 2. By extending the modular group to this genus, the same VEV can also account for the spontaneous breaking of the assumed CP symmetry. We present for the first time a quark model which is able to fit both the mass hierarchies...

105. Radiative Corrections in Axion EFT: Scheme Consistency and Phenomenology in B-Decays

Mr Atanu Samanta (Indian Institute of Technology Kanpur)

Contributed Talk

Axions and axion-like particles (ALPs) remain among the most compelling solutions to the strong CP problem and viable dark matter candidates. As experimental sensitivities at the intensity and cosmic frontiers increase, matching theoretical precision in effective field theory (EFT) is paramount. In this talk, we present a comprehensive, multi-loop EFT framework for ALPs. First, we address the...

200. Recent results from XENONnT

Sana Ouahada (University of Zurich)

Contributed Talk

The XENONnT experiment operates a liquid xenon time projection chamber at the INFN Laboratori Nazionali del Gran Sasso, designed to search for weakly interacting massive particles (WIMPs). Its ultra-low background rate and low energy threshold, achieved to maximize WIMP sensitivity, also enable the study of other rare processes.

In this talk, I will present the latest results from XENONnT....

33. Reconstructing $f(T)$ Gravity From Hubble Parameterization Constraints

Suraj Kumar Behera (VIT-AP university)

Poster

In this study, we have presented the cosmological model of the Universe that represents late time cosmic acceleration in torsion based gravitational theory, the $f(T)$ gravity. A well motivated parametrization for the Hubble parameter has been introduced and the free parameters involved are constrained using the cosmological datasets. With the constrained values of the free parameters, other...

192. Reconstructing dark energy with few assumptions

Daniel A. Kessler (University of Sheffield)

Contributed Talk

Baryon acoustic oscillation (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI) strengthen the cosmological evidence for dark energy beyond the cosmological constant to the ~3σ level when combined with cosmic microwave background (CMB) and Type Ia supernovae (SNe Ia) observations. This evidence is obtained assuming a dark energy equation of state restricted to linear order...

176. Reconstructing Sign-Changing Dark Energy Density: From Data to Fundamental Theory

Prof. Nihan Katırcı (Dogus University)

Contributed Talk

Recent cosmological observations continue to challenge the standard $\Lambda$CDM paradigm through persistent tensions in the Hubble constant $H_0$, the clustering amplitude $S_8$, and possible hints of nontrivial late-time dark-energy dynamics. In this talk, we discuss two complementary studies showing how sign transitions in the effective vacuum sector may arise naturally from modified...

177. Relaxing Lyman-$\alpha$ bounds by self-cooling Dark Sectors

Stefan Lederer (NCBJ)

Contributed Talk

Light dark matter is usually constraint by large-scale structure observations via Lyman-$\alpha$ lines to $m_\text{DM}\gtrsim \mathcal{O}(5\text{keV})$. I will discuss how these bounds can be relaxed for dark sectors which are produced non-thermally from the SM bath but cool themselves via $2\leftrightarrow3$ "cannibal" reactions.
Thermodynamic predictions of this cooling are in many regions...

111. Removing the Cosmological Bound on the Axion Scale via Confinement During Inflation

Lucy Elisabeth Komisel (Max-Planck Institute for Physics/LMU Munich)

Poster

We implement a scenario of early relaxation of the axion via a high scale confinement within $SU(5)$ grand unified theory and study an epoch of strong QCD in inflationary cosmology. We consider scenarios in which, during inflation, the $SU(5)$ is either entirely or partially in the confining phase.This generates an early potential for the axion and dilutes its energy density removing any...

138. Revisiting Instanton Effects in the Broken Phase

Takafumi Aoki (ICRR, The University of Tokyo)

Contributed Talk

Instanton effects in gauge theories with spontaneously broken gauge symmetries are relevant to several phenomenological settings, including electroweak baryon-number violating processes and nonperturbative contributions to axion physics. In such theories, the relevant configurations are not exact classical minima of the action, so evaluating their effects requires some care. Earlier work...

126. Screened Forces in a QCD-like Dark Sector on Galactic Scales

Mathilda Denison (University of Pennsylvania)

Contributed Talk

Persistent small-scale challenges to the ΛCDM cosmological model have motivated the consideration of dark matter models with richer phenomenology. We consider a dark QCD scenario in which dark axions mediate a screened force between dark baryons within dark matter halos. Finite-density corrections to the dark QCD quark condensate introduce a density-dependent interaction term between dark...

101. Search for Dark Matter candidates with CUPID-0

Sylvie Pietrarota (Sapienza University of Rome)

Poster

CUPID-0 was a pilot experiment in scintillating cryogenic calorimetry designed to search for neutrinoless double beta decay. An array of 26 ZnSe crystals coupled to bolometric light detectors was operated continuously for two years. CUPID-0 demonstrated full $\alpha$ to $\beta/\gamma$ background discrimination, set the most stringent limit on the neutrinoless double beta decay of $^{82}$Se,...

106. Search for keV Sterile Neutrinos with the KATRIN Experiment

Leo Laschinger (MPIK, TUM)

Contributed Talk

The KATRIN experiment is designed to measure the mass of the electron anti-neutrino by studying the high energy end of the tritium β decay spectrum. In addition, KATRIN is also a well suited instrument to explore the sterile neutrino hypothesis. The existence of sterile neutrinos would cause a kink-like distortion in the spectrum.
Using the same datasets as for the active neutrino mass,...

140. Search for the Majorana Nature of Neutrino with the LEGEND Experiment

Alex Biondi (Jagiellonian University in Krakow)

Contributed Talk

Search for the Majorana Nature of Neutrino with the LEGEND Experiment

A. Biondi on behalf of the LEGEND Collaboration

Observation of the neutrinoless double beta (0$\nu\beta\beta$) decay would establish that neutrinos are Majorana particles and demonstrate violation of lepton number, providing a key ingredient for understanding the origin of neutrino masses and the matter-antimatter...

208. Search for the rare Higgs boson decay H -> Z gamma

Xingchen Fan (Cornell University (US))

Contributed Talk

We present a search for the rare Higgs boson decay H→Zγ using proton–proton collision data recorded by the CMS experiment at the LHC at center-of-mass energies of 13 and 13.6 TeV, corresponding to a total integrated luminosity of 200 fb⁻¹. The analysis targets final states where the Z boson decays to an electron or muon pair. Sensitivity is enhanced through dedicated event categorization...

116. Searches for Dark Matter with the ATLAS Experiment at the LHC

Bernardo Ricci

Contributed Talk

The presence of a non-baryonic Dark Matter (DM) component in the Universe is inferred from the observation of its gravitational interaction. If Dark Matter interacts weakly with the Standard Model (SM) it could be produced at the LHC. The ATLAS Collaboration has developed a broad search program for DM candidates in final states with large missing transverse momentum produced in association...

117. Searches for New Physics in Effective Field Theory Approaches from ATLAS

Oleksii KURDYSH

Contributed Talk

We present two analyses searching for new physics in the context of effective field theory approaches from the ATLAS collaboration. The analyses use multiple experimental measurements across a range of processes in electroweak boson, top-quark and Higgs production to constrain dimension-6 operators. In addition multi-boson production measurements provide leading constraints on anomalous...

115. Searches for new physics using conventional signatures with the ATLAS Detector

Selaiman RIDOUANI

Contributed Talk

Many theories beyond the Standard Model (SM) have been proposed to address several of the SM shortcomings, often predicting new particles which can be searched for at the LHC. This can include extended Higgs sectors, supersymmetric particles, heavy vectors or scalars, vector-like fermions, and further exotic particles. This talk will cover several related searches, focusing on prompt...

114. Searches for new physics using unconventional signatures and techniques with the ATLAS detector

Sergei CHEKANOV

Contributed Talk

Many theories beyond the Standard Model (SM) have been proposed to address several of the SM shortcomings. Some of these beyond-the-SM extensions predict new particles or interactions directly accessible at the LHC, but which would leave unconventional signatures in the ATLAS detector. Alternatively, these signatures could be relatively standard, but could benefit from unusual techniques....

99. Slow force carriers in particle physics and cosmology

Francesco Serra (Johns Hopkins University)

Contributed Talk

I show that gauge theory and gravity admit local modifications in which all local symmetries are broken, leading to new gapless modes universally coupled to matter. The new modes have small speed, which suppresses all their interactions with matter, making them compatible with current observations. No new scales or fundamental fields are introduced in this approach, as the new physical modes...

22. Sterile neutrino dark matter from a TeV scale seesaw

SUHAIL KHAN (Centre for Theoretical Physics,Jamia Millia Islamia, New Delhi, India)

Contributed Talk

In this article, we investigate the phenomenological aspects of a feebly interacting sterile neutrino dark matter candidate within a low-scale seesaw framework. The Type-I seesaw model is augmented by a second complex scalar doublet ($\Phi_{\nu}$), which couples exclusively to the heavy right-handed neutrinos and the lepton doublet, thereby generating the neutrino Dirac mass term while the...

190. Supersymmetric solutions in 6D Euclidean U(1)^2 gauged supergravity

Danila Shkinderov (University of Oxford)

Poster

This project focuses on classifying supersymmetric solutions in 6D Euclidean U(1)^2 gauged supergravity. Five-dimensional SCFTs exhibit interesting features which we may probe by placing them on different curved backgrounds, however this can be difficult to study using field theory techniques. Holography, in particular the AdS/CFT correspondence, provides an alternative method. For example,...

74. Surrounding and the Missing Chapter in General Relativity: A Unified Approach to Gravitational Mysteries

Frederic Lassiaille (FL research)

Poster

The “Surrounding” model [1], based on a modification of Newton’s law, has demonstrated its ability to explain a variety of gravitational phenomena, including galactic rotation curves and anomalies traditionally attributed to dark matter. Recent improvements align the model with additional observational constraints, such as the Tully-Fisher relation and detailed small-galaxy velocity profiles,...

34. SUSY and non-SUSY analysis of truly confining gauge theories

Shota Saito (Kavli IPMU)

Contributed Talk

We classify 4D N=1 truly confining supersymmetric gauge theories, in which no center charges can be screened. This property guarantees that Wilson loops in the fundamental representation exhibit an area law. We systematically identify all such theories for simple Lie groups and determine the allowed matter content. In each theory, we find condensing magnetic operators, which are expected to...

38. Symmetry Constraints from Extra Dimensions

María Agustina Pereyra Grau (Universidad de Buenos Aires - Instituto de Astronomía y Física del Espacio)

Poster

We study how symmetries arising from extra dimensions can be used to derive constraints on string and supergravity effective actions. In Kaluza–Klein compactifications, some higher-dimensional symmetries are preserved, others are broken, and in special cases symmetry enhancements occur. While enhanced symmetries were shown to fix the higher-dimensional action before reduction [1,2], we show...

50. Testing modified gravity with gravitational wave lensing

Dr Serena Giardino (Imperial College London)

Contributed Talk

Gravitational waves propagating through the universe inevitably encounter massive objects, getting deflected and magnified. The presence of lenses such as galaxies, clusters, or stars breaks the symmetries of the FLRW metric, allowing for new interactions between different polarizations. These bear the signatures of modified gravity and imprint distinctive effects on the waveforms. I will...

172. The challenges of using Baryon Acoustic Oscillations distances for cosmology

Stefano Anselmi (INFN, Sezione di Padova)

Contributed Talk

One of the landmarks guiding our understanding of physical cosmology is the large-scale structure, defined as the large scale distributions of galaxies, as observed by galaxy surveys. In this context, the so-called Baryon Acoustic Oscillations, are considered one of the most powerful cosmological probes. They are generally deemed to provide distance measures independent of a specific...

162. The Einstein Static Universe as an initial condition for Inflation

Rinat Kagirov (University of Oxford)

Poster

Inflation requires highly homogeneous initial conditions on large scales. We investigate whether an initial Einstein static phase can naturally establish such conditions. In a hot, quasi-static Universe, thermal equilibrium can suppress inhomogeneities, providing a potential pre-inflationary homogenisation mechanism.

We construct a dynamical model in which a scalar field replaces the...

183. The ICARUS experiment at the Short-Baseline Neutrino program and the search for sterile neutrinos

Alessandro Menegolli

Contributed Talk

The ICARUS T600 LAr-TPC detector (760 t of ultrapure liquid argon) was successfully operated for three-years at the underground LNGS laboratory, carrying out a sensitive search for LSND-like anomalous appearance in the CERN Neutrinos to Gran Sasso beam. The LSND anomaly has been the subject of numerous experimental investigations over the past 25 years, suggesting the possible existence of a...

170. The Linear Point Standard Ruler and Its Application to the Euclid Survey

Francesca Passalacqua (INFN Padova)

Poster

The large-scale distribution of galaxies encodes information about acoustic waves that propagated in the primordial baryon–photon plasma, leaving a characteristic feature in the two-point correlation function at scales of order 150 Mpc. By exploiting this feature, a new observable, known as the Linear Point, has been identified and shown to be a powerful cosmological standard ruler.

In...

120. The NUCLEUS experiment for Coherent Elastic Neutrino-Nucleus Scattering

Matteo Cappelli (Sapienza Università di Roma e INFN, Roma I (IT))

Contributed Talk

Coherent elastic neutrino-nucleus scattering (CE$\nu$NS) offers a broad range of physical and technological applications. First predicted in 1974 and remained undetected until 2017, the process is currently entering the era of precision measurements. For this purpose, low energy neutrinos from nuclear reactors represent an ideal source, enabling the investigation of CE$\nu$NS in the fully...

80. The SABRE South Experiment at the Stawell Underground Physics Laboratory

Peter McNamara

Contributed Talk

SABRE is an international collaboration that will operate similar particle detectors in the Northern (SABRE North) and Southern Hemispheres (SABRE South). This innovative approach aims to distinguish potential dark matter signals from seasonal backgrounds: a pioneering strategy only feasible with a Southern Hemisphere experiment. SABRE South is located at the Stawell Underground Physics...

51. The SHiP/NA67 experiment at the ECN3 high-intensity beam facility at the CERN SPS

Walter Marcello Bonivento (INFN Cagliari)

Contributed Talk

The SHiP/NA67 experiment is a general-purpose intensity-frontier experiment for the search for feebly interacting GeV-scale particles and to perform neutrino physics measurements at the HI-ECN3 (high-intensity) beam facility at the CERN SPS, operated in beam-dump mode, taking full advantage of the available $4\times 10^{19}$ protons per year at 400 GeV. The collaboration is currently...

122. Thermal effects on Dark Matter production during cosmic reheating

Yannis Georis (Kavli IPMU)

Contributed Talk

The relic abundance of Dark Matter (DM) produced via thermal freeze-in is sensitive to the thermal history during and after cosmic reheating. In minimal models, this opens up the possibility to make predictions for collider observables by combining the requirement to match the DM relic abundance with observations of the Cosmic Microwave Background (CMB). We assess the impact of thermal...

161. Threading the Thimble: A Stable Route to Real-Time Path Integrals

Katarina Trailović (Institute Jožef Stefan)

Contributed Talk

Path integrals in real time are plagued by violently oscillatory phases, and Lefschetz thimble methods offer one of the cleanest ways to make sense of them — but only if the intersection numbers between thimbles and the original integration contour can be computed reliably. In practice, existing approaches have been limited to just one or two variables, leaving genuinely multivariable problems...

152. Toward a real-time theory of vacuum decay

Alex Jenkins (University of Cambridge)

Contributed Talk

False vacuum decay plays a pivotal role in many models of particle physics and the early Universe, from inflation to the electroweak vacuum. However, we lack a satisfying theoretical understanding of this process, with existing approaches working only in imaginary (Euclidean) time, and relying on assumptions that have yet to be empirically tested.
In this talk, I will describe ongoing efforts...

175. Towards Consistent Dark Energy Constraints from High- and Low-Redshift Probes with the Extended AP Test

Suvedha Suresh Naik (Korea Institute for Advanced Study (KIAS), Seoul, Republic of Korea)

Poster

Recent analyses of large-scale galaxy redshift surveys, such as those from Sloan Digital Sky Survey (SDSS) and Dark Energy Spectroscopic Instrument (DESI), as well as Type Ia supernova data, have made it possible to place meaningful constraints on the dark energy equation of state. Methods based on the Alcock–Paczynski test, which uses the clustering of large-scale structure as a standard...

135. Towards the final analysis of the KATRIN data

Karo Erhardt (KIT)

Contributed Talk

The KATRIN experiment aims at direct kinematic measurement of the neutrino mass with the expected sensitivity below 300 meV (90% CL), performing a high-resolution, high-statistics spectroscopy of tritium beta-decay. To reach such sensitivity, the systematic effects, modifying the measured electron spectrum shape have to be modeled and controlled by dedicated calibration measurements.
KATRIN...

46. Twisted and Curved Vacuum Spacetime with Gravitation and Electromagnetism : Application to Dark Energy in Cosmology

Lalaonirina Rakotomanana (Institut de Recherche Mathématique Rennes / Université de Rennes)

Poster

Introduction. The discovery of the accelerating expansion of the Universe by the two teams of Riess et al. and Perlmutter et al. independently in 1998 marked the beginning of a paradigm shift that sparked a significant new field of research in Cosmology. Dark Energy, in addition to the Dark Matter suggested by Zwicky et al. (1933) and later supported by Rubin (1970), was then postulated...

199. Universal Seesaw: Leptogenesis, Strong CP and Dark Radiation

Drona Vatsyayan (Carleton University)

Contributed Talk

We study the implications for leptogenesis in a class of left-right symmetric model, where all fermion masses are induced through the Universal Seesaw mechanism. Unlike conventional analyses, we do not use the decays of the neutrino embedded in the right-chiral lepton doublet, but rather those of the gauge-singlet mediators required for neutrino mass generation in the canonical Type-I seesaw....

158. Unveiling the Dark Universe with the Sun

Anne Davis

Contributed Talk

The sun is a powerful tool for investigating the dark universe. In the core of the sun light scalar particles can be produced via Primakoff process in the electric field of the ions and via the intense magnetic field. There can also be production vis the magnetic field in the tachocline. This allows for stringent constraints on new scalar particles which could play the role of dark energy....

72. UV, IR, and inflaton driven Freeze-in

Dimitrios Karamitros (University of Padova & INFN Padova)

Contributed Talk

We investigate a scenario in which the dark matter is produced via freeze-in with contributions from both the UV and IR. We also take into account an additional production mode from the decay of the inflaton. We analyze the parameter space at the level of the dark matter phase space distribution to assess potential impact of a non-thermal distribution, including bounds from Lyman-$\alpha$ measurements.

75. V-associated production & vector boson fusion of Higgs bosons as an LHC signature of CP violation

Álvaro Lozano Onrubia (IFT UAM-CSIC & Universidad Autónoma de Madrid)

Contributed Talk

Many well-motivated extensions of the Standard Model predict new, entirely bosonic sources of CP violation (CPV). In these scenarios, the simultaneous observation of carefully selected bosonic processes emerges as a simple yet powerful method to unambiguously reveal the presence of CPV. The present study, which establishes a promising framework of CPV searches for the upcoming HL-LHC era,...

182. Varieties of four-dimensional gauge theories

Khoi Le Nguyen Nguyen (DAMTP, University of Cambridge)

Contributed Talk

Given a gauge Lie algebra, it is natural to seek representations for four-dimensional spacetime fermions that are anomaly-free and chiral. However, this problem is difficult to solve in full generality. Even for irreducible representations, where we only have to study $\mathfrak{su}(n)$ for $n\geq3$, solutions would seem to be few and far between: a trial-and-error scan by Eichten, Kang and...

84. Vector Resonances at Muon and Wakefield Colliders

Massimo Cipressi (SISSA)

Contributed Talk

We explore the potential of future high-energy lepton colliders to probe heavy vector resonances.
At wakefield colliders, intense beam-beam interactions produce radiation, called beamstrahlung,
which redistributes luminosity from the nominal energy across a broad spectrum of lower collision
energies. We show that this effect, conventionally viewed as a drawback, dramatically...

154. Viable interactions in the dark sector

Erik Jensko (University College London)

Contributed Talk

Extensions of $\Lambda$CDM with interactions between dark matter and dark energy are a promising route to address the current cosmic tensions. In this talk, I will discuss interacting dark sector models with entropy couplings, which give rise to pure-momentum transfer in cosmology. While the background evolution is unchanged, the models are characterised by distinct observational signatures at...

189. Volume as Time: Boundary Dynamics Near Black Hole Horizons

Farbod-Sayyed Rassouli (University of Nottingham)

Contributed Talk

Different notions of time arise from different choices of observer. In cosmological settings, a particularly natural choice is the spacetime volume, which is conjugate to the cosmological constant. This gives rise to unimodular time, deparametrizing the Wheeler–DeWitt equation into a Schrödinger-like evolution equation. I will first explain how this construction appears in arbitrary dimension,...

159. When Boson Stars Collapse Bubbles Can Nucleate

Nicklas Ramberg (SISSA)

Poster

We present a new classical mechanism for nucleation of bubbles of true vacuum. The mechanism arises when dense boson stars form in the false vacuum. As the boson stars collapse due to attractive self-interactions, the field inside the star cores is enhanced beyond the potential barrier. Subsequently the stars explode as true vacuum bubbles, and induce a cosmological phase transition. The...

186. X-ray femtolensing probes asteroid-mass black holes

Benjamin Lehmann (Massachusetts Institute of Technology)

Contributed Talk

The asteroid-mass regime is the key remaining window in which primordial black holes could constitute all of dark matter. I will present a new method to probe a substantial portion of this window using X-ray femtolensing. While photometric microlensing requires long observations of very stable compact sources, the energy-dependent features imprinted onto X-ray spectra furnish a clean target...

81. ζ/η, Photoproduction in Paramagnetic MQGP and (Almost) Contact Structures

SHIVAM SINGH KUSHWAH (IIT Roorkee)

Contributed Talk

Using the M-theory uplift inclusive of O(R^4)-corrections as worked out in V.Yadav, A.Misra [ATMP 26(2022)10, 3801-3894], of thermal QCD-like theories in the deconfined phase at intermediate-coupling, the bulk-viscosity-to-shear-viscosity ratio (ζ/η) is calculated (via Green-Kubo/Eling-Oz methods), showing that the O(R^4 ) corrections enable an interpolation between strong- and weak-coupling...