Conveners
Cosmology
- Tamara Davis
Cosmology
- Philippe Brax
Cosmology: Inflation
- Konstantinos Dimopoulos
- Laura Iacconi (Queen Mary University of London)
Cosmology: Joint MG&DE
- Supriya Pan
- Matteo Martinelli (INAF - OAR)
- Laura Herold
- Alessandra Silvestri
Cosmology
- Anne Davis
Cosmology: Neutrinos in Cosmology
- Olga Mena
- Willem Elbers (Durham University)
Cosmology: Modified Gravity
- Matteo Martinelli (INAF - OAR)
- Alessandra Silvestri
Cosmology: Cosmic Tensions
- William Giarรจ
- Elsa Teixeira (Laboratoire Univers et Particules de Montpellier, University of Montpellier)
Cosmology: Dark Energy
- Laura Herold
- Supriya Pan
Cosmology: Dark Matter in cosmology
- Laura Covi (Georg August Universitaet Goettingen (DE))
- Clare Burrage (University of Nottingham)
Cosmology
- There are no conveners in this block
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Hiranya Peiris22/06/2026, 14:00
Next-generation cosmological surveys โ LSST, Euclid, Roman โ will be limited not by statistical power but by systematic uncertainties rooted in our understanding of galaxy populations. Photometric redshift calibration, intrinsic alignments, and baryonic effects on the matter power spectrum are all manifestations of the same underlying problem: cosmological inference requires an accurate model...
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Tessa Baker22/06/2026, 14:35
Recent combinations of BAO, supernovae and CMB data prefer cosmologies with an evolving dark energy equation of state, w(z), which crosses the phantom divide (w=-1). But parameterisations of w(z) are not, in themselves, complete physical models of dark energy.
In this talk weโll ask: what kind of underlying modified gravity or dark energy models give rise to phantom-crossing behaviour?...
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philippe brax (CEA)22/06/2026, 15:10
Recent surveys suggest that dark energy could be dynamical and cross the phantom divide. This can be easily reproduced in scalar-tensor theories where
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matter couples to dark energy. This potentially leads to serious gravitational problems in the solar system which can be evaded thanks to screening. I will argue that
multi-field models could both reconcile phantom crossing and screening. -
Julien Lesgourgues (TTK, RWTH Aachen University)23/06/2026, 11:15
I will briefly review the currently confusing situation regarding cosmological bounds on the neutrino mass. In the future, there is a hope to clarify the situation by detecting the actual neutrino free-streaming effect in large-scale structures. In this regard, I will present a new method allowing to easily incorporate the scale-dependance of the growth factor induced by massive neutrinos (or...
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Florian Beutler23/06/2026, 11:50
Spectroscopic surveys map the threeโdimensional largeโscale structure of the Universe, providing precise tests of cosmic expansion and the growth of structure. The Dark Energy Spectroscopic Instrument (DESI) is a StageโIV experiment on the 4โm Mayall telescope, using 5000 robotically positioned fibres to obtain spectra for more than 40 million galaxies and quasars over ~14,000 degยฒ. I will...
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Lucien Heurtier (King's College London)23/06/2026, 14:15Contributed 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...
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Matteo Martinelli (INAF - OAR)23/06/2026, 14:15
The recent baryon acoustic oscillation (BAO) measurements from the DESI collaboration have revealed a first hint towards a deviation from a cosmological constant, signaling a preference for dynamical dark energy. In this talk, we explore the deep theoretical implications of these observations for dark energy and gravitational physics. Utilizing a model-agnostic, non-parametric reconstruction...
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Benjamin Muntz (University of Nottingham)23/06/2026, 14:35Contributed 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...
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Martin Teuscher (LPSC Grenoble, France)23/06/2026, 14:35Contributed 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...
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Dr JAVIER RUBIO (Universidad Complutense de Madrid)23/06/2026, 14:55Contributed 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...
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Prof. Nihan Katฤฑrcฤฑ (Dogus University)23/06/2026, 14:551Contributed 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...
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James Hallam (Institute of Cosmology and Gravitation - University of Portsmouth)23/06/2026, 15:15Contributed 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...
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Anish Ghoshal (University of Warsaw, Poland)23/06/2026, 15:15Contributed 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...
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23/06/2026, 15:35
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Ethan Milligan (QMUL)23/06/2026, 15:35Contributed 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...
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23/06/2026, 15:55
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Enrico Specogna (University of Sheffield)23/06/2026, 16:00Contributed 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...
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Oksana Iarygina (Nordita)23/06/2026, 16:15Contributed 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,...
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Patrick Adolf23/06/2026, 16:20Contributed 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.
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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... -
Gabriele Barca (University of the Basque Country)23/06/2026, 16:35Contributed 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...
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Nils A. Nilsson23/06/2026, 16:40
Bumblebee gravity is currently a popular topic, and models are ubiquitus in the literature. In this talk, I will first review the current state of the art; then, I will show that the model propagates ghosts on cosmological as well as arbitrary backgrounds, resulting in a no-go theorem in the context of this model.
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Guillermo Fernando Quispe Peรฑa (Simon Fraser University)23/06/2026, 16:55Contributed 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...
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Matteo Pegorin (University of Padova & INFN Padova)23/06/2026, 17:00Contributed Talk
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...
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Parth Bhargava (ICG, Portsmouth)23/06/2026, 17:15Contributed 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...
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Adam Riess24/06/2026, 09:00
One of the most basic questions in cosmology is: How fast is the Universe expanding today? Two powerful approaches give answers that should agree but do not. Measurements based on the cosmological model calibrated by the cosmic microwave background predict one value for the Hubble constant H0โ, while direct measurements using the cosmic distance ladder give a higher value. The difference, now...
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Dr Vivian Poulin (LUPM, CNRS & U. de Montpellier, France)24/06/2026, 09:35
In this talk, I will present an updated โH0 Olympicsโ analysis using the latest cosmological datasets from Planck NPIPE, ACT DR6, SPT-3G, and DESI. We systematically compare twelve representative models from the recent literature, covering both early- and late-time proposals to resolve the Hubble tension. We also examine whether extensions such as a time-varying dark energy equation of state...
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Tamara Davis24/06/2026, 10:10
Based on 6 years of observations and ~1,500 new high-redshift supernovae, the Dark Energy Survey (DES) team presented tentative evidence in 2024 that dark energy may be changing with time. A few months later the Dark Energy Spectroscopic Instrument (DESI) team also presented hints of time-varying dark energy, by mapping the distribution of galaxies. This talk will review the current state of...
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Salvador ROSAURO-ALCARAZ (LPCA - CNRS)25/06/2026, 09:10Contributed 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.
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Emre Ozulker25/06/2026, 09:30Contributed 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...
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Prof. Bivudutta Mishra (BITS-Pilani, Hyderabad Campus)25/06/2026, 09:30Contributed 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...
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Julien Froustey (IFIC (CSIC-UV))25/06/2026, 09:30Contributed 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...
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Gisela Cristina Camacho Ciurana (ICE-CSIC)25/06/2026, 09:50Contributed 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...
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Sotirios Karamitsos (University of Tartu)25/06/2026, 09:50Contributed 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...
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Dr Guillermo Franco Abellรกn (IFIC, CSIC - University of Valencia)25/06/2026, 09:50Contributed 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...
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Laura Herold25/06/2026, 10:10
The DESI galaxy survey has recently placed the tightest constraint on the sum of neutrino masses to date. For such effects โbelow the detection limitโ, where data can only infer upper bounds, Bayesian and frequentist methods can give important complementary information. I will begin with a short overview of the frequentist profile-likelihood method, its advantages and limitations. Using a...
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Sergi Sirera (Institute of Cosmology and Gravitation)25/06/2026, 10:10Contributed 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...
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Mario Fernandez Navarro (University of Zurich)25/06/2026, 10:10Contributed 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...
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Sinah Legner (University of Cambridge)25/06/2026, 10:30Contributed 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.
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We investigate the [Torsion Condensation (TorC) model][2], a framework derived from [Poincare Gauge Theory][3] that... -
Paul Shah (UCL)25/06/2026, 10:30Contributed 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?
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Rasmi Hajjar (CCAPP - Ohio State University)25/06/2026, 10:30Contributed 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...
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25/06/2026, 10:50
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25/06/2026, 10:50
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25/06/2026, 10:50
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Tanisha Jhaveri (University of Chicago)25/06/2026, 11:10Contributed 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...
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Xubin Hu (University of Southampton)25/06/2026, 11:10Contributed 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...
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Alessandro Vadala (INAF - Astronomical Observatory of Rome)25/06/2026, 11:10Contributed 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...
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Dr Trupti Patil (Korea Institute for Advanced Study, Seoul, South Korea)25/06/2026, 11:30Poster
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 matterโdark energy model and discuss...
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Nastassia Grimm (University of Portsmouth)25/06/2026, 11:30Contributed 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,...
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Pietro Ghedini (IFIC, CSIC - UV)25/06/2026, 11:30Contributed 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 $\xi_{\nu_\mathrm{x}}$...
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Adam Smith (University of Sheffield)25/06/2026, 11:50Contributed 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...
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Nicola Barbieri (IFIC (CSIC-UV))25/06/2026, 11:50Contributed 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 $\Delta N_{\rm eff}$....
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Dr Serena Giardino (Imperial College London)25/06/2026, 11:50Contributed Talk
Gravitationalย 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 ofย modifiedย gravityย and imprint distinctive effects on theย waveforms. I will...
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Neel Shah (University of Portsmouth)25/06/2026, 12:10Contributed 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,...
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Angus Spalding (Univeristy of Southampton)25/06/2026, 12:10Contributed 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...
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Suvedha Suresh Naik (Korea Institute for Advanced Study (KIAS), Seoul, Republic of Korea)25/06/2026, 12:10Poster
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 AlcockโPaczynski test, which uses the clustering of large-scale structure as a standard...
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26/06/2026, 09:10
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Erik Jensko (University College London)26/06/2026, 09:10Contributed 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...
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Olga Garcia Gallego (Institute of Astronomy, University of Cambridge)26/06/2026, 09:30Contributed 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). On small scales, the Lyman-alpha 1D flux power spectrum is uniquely sensitive to both the properties of dark matter and the complex gas dynamics driven by IGM photoheating during reionization, offering...
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Elsa Teixeira (Laboratoire Univers et Particules de Montpellier, University of Montpellier)26/06/2026, 09:30Contributed Talk
Early Dark Energy (EDE) is a well-studied extension of ฮCDM
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proposed to address the Hubble tension. In these models, a new dark
energy component, typically described by an axion-like scalar field,
becomes dynamically relevant at early times and then rapidly dilutes
around matter-radiation equality, leaving a negligible contribution to
the late-time energy budget. Throughout this active... -
Daniel A. Kessler (University of Sheffield)26/06/2026, 09:50Contributed 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 ~3ฯ 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...
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Stefan Lederer (NCBJ)26/06/2026, 09:50Contributed 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.
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Thermodynamic predictions of this cooling are in many regions... -
Yuejia Zhai (University of Sheffield)26/06/2026, 10:10Contributed Talk
We focused on a phenomenological interacting dark energy model (IDE) with energy-momentum transfer from dark matter to dark energy through a coupling $Q = ฮพ\mathcal{H}ฯ_{DE}$. 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...
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Dimitrios Karamitros (University of Padova & INFN Padova)26/06/2026, 10:10Contributed 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.
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William Giarรจ26/06/2026, 10:30
In this talk, I will discuss how recent DESI results may reshape our understanding of the dark energy sector. I will focus on the emerging preference for late-time dynamical dark energy and its possible connection with early-time components active before recombination, often invoked to address the Hubble tension. I will ask whether early- and late-time dark energy require distinct extensions...
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Yannis Georis (Kavli IPMU)26/06/2026, 10:30Contributed 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...
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26/06/2026, 10:50
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26/06/2026, 10:50
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Prof. Konstantinos Dimopoulos (Lancaster University)26/06/2026, 11:10Contributed 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 manifoldโs 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...
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Anne Davis26/06/2026, 11:10Contributed 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....
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Hanyu Cheng26/06/2026, 11:30Contributed 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...
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Mathilda Denison (University of Pennsylvania)26/06/2026, 11:30Contributed Talk
Persistent small-scale challenges to the ฮCDM 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...
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Marรญa Pรฉrez Garrote (Universidad de Salamanca)26/06/2026, 11:50Contributed 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...
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Ludwig Schmidt (Technical University of Munich)26/06/2026, 11:50Contributed 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.
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We find that dissipation qualitatively changes the gravothermal evolution of SIDM halos beyond simply... -
Dong Ha Lee (University of Sheffield)26/06/2026, 12:10Contributed 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...
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Benjamin Lehmann (Massachusetts Institute of Technology)26/06/2026, 12:10Contributed 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 usingย 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...
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Dr Djuna Croon (IPPP Durham)26/06/2026, 16:20
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David Mulryne (Queen Mary University of London)26/06/2026, 16:55
Taylor expansion methods based on the separate universe approximation, or more general approaches that do not rely on this approximation, can provide insight into the debate on the strength of loop corrections in inflationary models with a large peak. Such a peak is needed for the production of primordial black holes and scalar-induced gravitational waves. In particular, these methods can...
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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...
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