A5044999635- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Radio Astronomy Observations and Technology
- Particle physics theoretical and experimental studies
- Geophysics and Gravity Measurements
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Neutrino Physics Research
- Computational Physics and Python Applications
- Astronomy and Astrophysical Research
- Relativity and Gravitational Theory
- Superconducting and THz Device Technology
- Biofield Effects and Biophysics
- Scientific Research and Discoveries
- Quantum Electrodynamics and Casimir Effect
- Mechanical and Optical Resonators
- Black Holes and Theoretical Physics
- Photonic and Optical Devices
- Photonic Crystals and Applications
- Interdisciplinary Research and Collaboration
- Advanced Thermodynamics and Statistical Mechanics
Helsinki Institute of Physics
2022-2023
University of Helsinki
2022-2023
Université Libre de Bruxelles
2020-2022
Institut de Physique
2021
RWTH Aachen University
2018-2020
University of Bath
2019
We report on the implications for cosmic inflation of 2018 Release Planck CMB anisotropy measurements. The results are fully consistent with two previous cosmological releases, but have smaller uncertainties thanks to improvements in characterization polarization at low and high multipoles. temperature, polarization, lensing data determine spectral index scalar perturbations be $n_\mathrm{s}=0.9649\pm 0.0042$ 68% CL show no evidence a scale dependence $n_\mathrm{s}.$ Spatial flatness is...
Many attempts to solve the Hubble tension with extended cosmological models combine an enhanced relic radiation density, acting at level of background cosmology, new physical ingredients affecting evolution perturbations. Several authors have pointed out ability combined Baryon Acoustic Oscillation (BAO) and Big Bang Nucleosynthesis (BBN) data probe history independently both CMB maps supernovae data. Using state-of-the-art assumptions on BBN, we confirm that BAO, deuterium, helium are in...
We forecast the main cosmological parameter constraints achievable with CORE space mission which is dedicated to mapping polarisation of Cosmic Microwave Background (CMB). was recently submitted in response ESA's fifth call for medium-sized proposals (M5). Here we report results from our pre-submission study impact various instrumental options, particular telescope size and sensitivity level, review great, transformative potential as proposed. Specifically, assess on a broad range...
We forecast the sensitivity of thirty-five different combinations future Cosmic Microwave Background and Large Scale Structure data sets to cosmological parameters total neutrino mass. work under conservative assumptions accounting for uncertainties in modelling systematics. In particular, galaxy redshift surveys, we remove information coming from non-linear scales. use Bayesian parameter extraction mock likelihoods avoid Fisher matrix uncertainties. Our grid results allows a direct...
Dark matter coupled solely gravitationally can be produced through the decay of primordial black holes in early universe. If dark is lighter than initial hole temperature, it could warm enough to subject structure formation constraints. In this paper we perform a more precise determination these We first evaluate phase-space distribution, without relying on instantaneous approximation. then interface distribution with Boltzmann code extract corresponding power spectrum, which find match...
Several interesting Dark Matter (DM) models invoke a dark sector leading to two types of relic particles, possibly interacting with each other: non-relativistic DM, and relativistic Radiation (DR). These have consequences for cosmological observables, could in principle solve problems like the small-scale cold DM crisis, Hubble tension, and/or low $\sigma_8$ value. Their behaviour is captured by ETHOS parametrisation, which includes DR-DM scattering rate scaling power-law temperature, $T^n$....
Future observations of cosmic microwave background (CMB) polarisation have the potential to answer some most fundamental questions modern physics and cosmology, including: what physical process gave birth Universe we see today? What are dark matter energy that seem constitute 95% density Universe? Do need extensions standard model particle interactions? Is ΛCDM cosmological scenario correct, or missing an essential piece puzzle? In this paper, list requirements for a future CMB survey...
The emergence of an increasingly strong tension between the Hubble rate inferred from early- and late-time observations has reinvigorated interest in nonstandard scenarios, with aim reconciling these measurements. One such model involves interactions Dark Matter Energy. Here we consider a specific form coupling two fluids proportional to Energy energy density, which been studied extensively literature claimed substantially alleviate tension. We complement work already discussed several...
Spectral distortions and anisotropies of the CMB provide independent complementary probes to study energy injection processes in early universe. Here we discuss synergy between these observables, show promising future spectral distortion missions constrain both exotic non-exotic injections. We that conventional such as Big Bang Nucleosynthesis can benefit from even be surpassed by experiments. For this, have implemented a unified framework within Boltzmann code CLASS consistently treat...
Dark matter (DM) from freeze-in or superWIMP production is well known to imprint non-cold DM signatures on cosmological observables. We derive constraints Lyman-$\alpha$ forest observations for both cases, basing ourselves a reinterpretation of the existing limits thermal warm DM. exclude masses below 15 keV freeze-in, in good agreement with previous literature, and provide generic lower mass bound superWIMPs that depends mother particle decay width. Special emphasis placed mixed scenario,...
The increasingly significant tensions within $\Lambda$CDM, combined with the lack of detection dark matter (DM) in laboratory experiments, have boosted interest non-minimal sectors, which are theoretically well-motivated and inspire new search strategies for DM. Here we consider, first time, possibility DM having simultaneous interactions photons, baryons, radiation (DR). We developed a efficient version Boltzmann code CLASS that allows one species to multiple interaction channels. With this...
In this work we investigate the possibility that dark matter and (massive) neutrinos can interact via a simple, constant cross section. Building on previous numerical efforts, constrain model with Cosmic Microwave Background, Baryon Acoustic Oscillations, and, in particular, Lyman-$\ensuremath{\alpha}$ data. We find latter hint to significant departure from $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$, preference for an interaction strength about $3\ensuremath{\sigma}$ away zero. trace origin...
Astroparticle physics is undergoing a profound transformation, due to series of extraordinary new results, such as the discovery high-energy cosmic neutrinos with IceCube, direct detection gravitational waves LIGO and Virgo, many others. This white paper result collaborative effort that involved hundreds theoretical astroparticle physicists cosmologists, under coordination European Consortium for Theory (EuCAPT). Addressed whole community, it explores upcoming opportunities challenges our...
Abstract Recent cosmological tensions have rekindled the search for models beyond ΛCDM that cause a suppression of matter power spectrum. Due to small scales accessible Lyman-α data they are an excellent additional tool probe such models. In this work we extend recently-developed approach using constrain spectrum caused by almost any mixture cold and non-standard dark matter. We highlight steps involved in development corresponding likelihood will be publicly released upon publication work....
Abstract A gravitational wave background from a first order phase transition in the early universe may be observable at millihertz (GW) detectors such as Laser Interferometer Space Antenna (LISA). In this paper we introduce and test method for investigating LISA's sensitivity to waves using parametrised templates an approximation more complete physical model. The motivation developing is provide less computationally intensive way perform Markov Chain Monte Carlo (MCMC) inference on...
Characterizing chirality in nanodevices is often plagued by measurement ambiguities. New experiments demonstrate a breakthrough that improves sensitivity of such characterization 5 orders magnitude.
Many models of dark matter have been proposed in attempt to ease the $S_8$ tension between weak lensing and CMB experiments. One such exciting possibility is cannibalistic (CanDM), which has exothermal number-changing interactions allowing it stay warm far into its non-relativistic regime. Here we investigate cosmological implications CanDM how impacts anisotropies power spectrum, by implementing model within a linear Einstein-Boltzmann solver. We show that suppresses small scale spectrum...
Abstract Stochastic backgrounds of gravitational waves from primordial first-order phase transitions are a key probe physics beyond the Standard Model. They represent one best prospects for observing or constraining new with LISA wave observatory. However, large foreground population galactic binaries in same frequency range represents challenge, and will hinder recovery stochastic background. To test recoverability background, we use Simulation Suite to generate data incorporating both...
Abstract Measurements of the cosmic microwave background (CMB) spectral distortions (SDs) will open a new window on very early universe, providing information complementary to that gathered from CMB temperature and polarization anisotropies. In this paper, we study their synergy as function characteristics considered experiments. particular, examine wide range sensitivities for possible SD measurements, spanning FIRAS up noise levels 1000 times better than PIXIE, constraining power when...
Abstract Measuring spectral distortions (SDs) of the cosmic microwave background (CMB) will provide new constraints on previously unexplored scales primordial power spectrum, allowing us to extend probed parameter space by several orders magnitude in k-space, which could have significant implications context black holes and gravitational waves, among others. Here we discuss how various models inflation can be tightly constrained combination current future CMB SD anisotropy experiments. In...
Stochastic backgrounds of gravitational waves from primordial first-order phase transitions are a key probe physics beyond the Standard Model. They represent one best prospects for observing or constraining new with LISA wave observatory. However, large foreground population galactic binaries in same frequency range represents challenge, and will hinder recovery stochastic background. To test recoverability background, we use Simulation Suite to generate data incorporating both background an...