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the nanograv collaboration has recently observed first evidence of a gravitational wave background (gwb) in pulsar timing data. here we explore the possibility that this gwb is due to new physics, and show that the signal can be well fit also with peaked spectra like the ones expected from phase transitions (pts) or fr... | whispers from the dark side: confronting light new physics with nanograv data |
we present a joint cosmic shear analysis of the dark energy survey (des y3) and the kilo-degree survey (kids-1000) in a collaborative effort between the two survey teams. we find consistent cosmological parameter constraints between des y3 and kids-1000 which, when combined in a joint-survey analysis, constrain the par... | des y3 + kids-1000: consistent cosmology combining cosmic shear surveys |
we present the data release 14 quasar catalog (dr14q) from the extended baryon oscillation spectroscopic survey (eboss) of the sloan digital sky survey iv (sdss-iv). this catalog includes all sdss-iv/eboss objects that were spectroscopically targeted as quasar candidates and that are confirmed as quasars via a new auto... | the sloan digital sky survey quasar catalog: fourteenth data release |
theories with higher order time derivatives generically suffer from ghost-like instabilities, known as ostrogradski instabilities. this fate can be avoided by considering ``degenerate'' lagrangians, whose kinetic matrix cannot be inverted, thus leading to constraints between canonical variables and a reduced number of ... | degenerate higher derivative theories beyond horndeski: evading the ostrogradski instability |
during a cosmological first-order phase transition, particles of the plasma crossing the bubble walls can radiate a gauge boson. the resulting pressure cannot be computed perturbatively for large coupling constant and/or large supercooling. we resum the real and virtual emissions at all leading-log orders, both analyti... | friction pressure on relativistic bubble walls |
astronomical observations reveal a major deficiency in our understanding of physics—the detectable mass is insufficient to explain the observed motions in a huge variety of systems given our current understanding of gravity, einstein's general theory of relativity (gr). this missing gravity problem may indicate a break... | from galactic bars to the hubble tension: weighing up the astrophysical evidence for milgromian gravity |
we present a measurement of baryonic acoustic oscillations (baos) from lyα absorption and quasars at an effective redshift $z=2.33$ using the complete extended baryonic oscillation spectroscopic survey (eboss). the 16th and final eboss data release (sdss dr16) contains all data from eboss and its predecessor, the baryo... | the completed sdss-iv extended baryon oscillation spectroscopic survey: baryon acoustic oscillations with lyα forests |
planck has mapped the microwave sky in temperature over nine frequency bands between 30 and 857 ghz and in polarization over seven frequency bands between 30 and 353 ghz in polarization. in this paper we consider the problem of diffuse astrophysical component separation, and process these maps within a bayesian framewo... | planck 2015 results. x. diffuse component separation: foreground maps |
this snowmass 2021 white paper describes the cosmic microwave background stage 4 project cmb-s4, which is designed to cross critical thresholds in our understanding of the origin and evolution of the universe, from the highest energies at the dawn of time through the growth of structure to the present day. we provide a... | snowmass 2021 cmb-s4 white paper |
gravitational waves from a first-order cosmological phase transition, at temperatures at the mev-scale, would arguably be the most exciting explanation of the common red spectrum reported by the nanograv collaboration, not the least because this would be direct evidence of physics beyond the standard model. here we per... | does nanograv observe a dark sector phase transition? |
recent observations from several pulsar timing array (pta) collaborations have unveiled compelling evidence for a stochastic signal in the nanohertz band. this signal aligns remarkably with a gravitational wave (gw) background, potentially originating from the first-order color charge confinement phase transition. dist... | nanograv hints for first-order confinement-deconfinement phase transition in different qcd-matter scenarios |
using the murchison widefield array (mwa), the low-frequency square kilometre array precursor located in western australia, we have completed the galactic and extragalactic all-sky mwa (gleam) survey, and present the resulting extragalactic catalogue, utilizing the first year of observations. the catalogue covers 24 83... | galactic and extragalactic all-sky murchison widefield array (gleam) survey - i. a low-frequency extragalactic catalogue |
gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. in this work, we have extended the search for lensing signatures to all binary black hole events... | search for gravitational-lensing signatures in the full third observing run of the ligo-virgo network |
this letter presents the results from pointlike neutrino source searches using ten years of icecube data collected between april 6, 2008 and july 10, 2018. we evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 ... | time-integrated neutrino source searches with 10 years of icecube data |
this study investigates the classical higgs inflation model with a modified higgs potential featuring a dip. we examine the implications of this modification on the generation of curvature perturbations, stochastic gravitational wave production, and the potential formation of primordial black holes (pbhs). unlike the c... | nanograv signal and pbh from the modified higgs inflation |
in this work we present several characteristic examples of theories of gravity and particle physics scenarios that may yield an observable energy spectrum of stochastic primordial gravitational waves, compatible with the 2023 nanograv observations. the resulting theories yield a flat or a peaklike energy spectrum, and ... | flat energy spectrum of primordial gravitational waves versus peaks and the nanograv 2023 observation |
the square kilometre array (ska) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. the ska will address many important topics in astronomy, ranging from planet formation to d... | fundamental physics with the square kilometre array |
to date, 241 individual molecular species, composed of 19 different elements, have been detected in the interstellar and circumstellar medium by astronomical observations. these molecules range in size from two atoms to 70 and have been detected across the electromagnetic spectrum from centimeter wavelengths to the ult... | 2021 census of interstellar, circumstellar, extragalactic, protoplanetary disk, and exoplanetary molecules |
we show that the recent nanograv result can be interpreted as a stochastic gravitational wave signal associated to formation of primordial black holes from high-amplitude curvature perturbations. the indicated amplitude and power of the gravitational wave spectrum agrees well with formation of primordial seeds for supe... | did nanograv see a signal from primordial black hole formation? |
we review the current status of early dark energy (ede) models proposed to resolve the "hubble tension", the discrepancy between "direct" measurements of the current expansion rate of the universe and "indirect measurements" for which the values inferred rely on the λcdm cosmological model calibrated on early-universe ... | the ups and downs of early dark energy solutions to the hubble tension: a review of models, hints and constraints circa 2023 |
we report a correlation between the radial acceleration traced by rotation curves and that predicted by the observed distribution of baryons. the same relation is followed by 2693 points in 153 galaxies with very different morphologies, masses, sizes, and gas fractions. the correlation persists even when dark matter do... | radial acceleration relation in rotationally supported galaxies |
we measure weak lensing cosmic shear power spectra from the 3-year galaxy shear catalog of the hyper suprime-cam (hsc) subaru strategic program imaging survey. the shear catalog covers 416 deg2 of the northern sky, with a mean i -band seeing of 0.59 arcsec and an effective galaxy number density of 15 arcmin-2 within ou... | hyper suprime-cam year 3 results: cosmology from cosmic shear power spectra |
the present rate of the expansion of our universe, the hubble constant, can be predicted from the cosmological model using measurements of the early universe, or more directly measured from the late universe. but as these measurements improved, a surprising disagreement between the two appeared. in 2019, a number of in... | the expansion of the universe is faster than expected |
unidentified infrared emission bands are ubiquitous in many astronomical sources. these bands are widely, if not unanimously, attributed to collective emissions from polycyclic aromatic hydrocarbon (pah) molecules, yet no single species of this class has been identified in space. using spectral matched filtering of rad... | detection of two interstellar polycyclic aromatic hydrocarbons via spectral matched filtering |
sterile neutrinos are natural extensions to the standard model of particle physics in neutrino mass generation mechanisms. if they are relatively light, less than approximately 10 kev, they can alter cosmology significantly, from the early universe to the matter and radiation energy density today. here, we review the c... | sterile neutrinos in cosmology |
we present constraints on the tensor-to-scalar ratio r using a combination of bicep/keck 2018 (bk18) and planck pr4 data allowing us to fit for r consistently with the six parameters of the λ cdm model. we discuss the sensitivity of constraints on r to uncertainties in the λ cdm parameters as defined by the planck data... | improved limits on the tensor-to-scalar ratio using bicep and planck data |
recent pulsar timing array (pta) experiments have reported strong evidence of the stochastic gravitational wave background (sgwb). if interpreted as primordial gravitational waves (gws), the signal favors a strongly blue-tilted spectrum. consequently, the nonsingular cosmology, which is able to predict a strongly blue-... | pulsar timing array observations as possible hints for nonsingular cosmology |
the primordial black holes (pbhs) are a well-established probe for new physics in the very early universe. we discuss here the possibility of pbh agglomeration into clusters that may have several prominent observable features. the clusters can form due to closed domain walls appearance in the natural and hybrid inflati... | clusters of primordial black holes |
we report the dark matter search results obtained using the full 132 ton·day exposure of the pandax-ii experiment, including all data from march 2016 to august 2018. no significant excess of events is identified above the expected background. upper limits are set on the spin-independent dark matter-nucleon interactions... | results of dark matter search using the full pandax-ii exposure |
the recently released data by pulsar timing array (pta) collaborations have amassed substantial evidence corroborating the existence of a stochastic signal consistent with a gravitational-wave background at frequencies around the nanohertz regime. we investigate the situation in which the pta signal originates from sca... | probing the equation of state of the early universe with pulsar timing arrays |
we present measurements of the e -mode (e e ) polarization power spectrum and temperature-e -mode (t e ) cross-power spectrum of the cosmic microwave background using data collected by spt-3g, the latest instrument installed on the south pole telescope. this analysis uses observations of a 1500 deg2 region at 95, 150, ... | measurements of the e -mode polarization and temperature-e -mode correlation of the cmb from spt-3g 2018 data |
increasingly stringent limits from lhc searches for new physics, coupled with lack of convincing signals of weakly interacting massive particle (wimp) in dark matter searches, have tightly constrained many realizations of the standard paradigm of thermally produced wimps as cold dark matter. in this article, we review ... | dark matter production in the early universe: beyond the thermal wimp paradigm |
the quijote simulations are a set of 44,100 full n-body simulations spanning more than 7000 cosmological models in the $\{{{\rm{\omega }}}_{{\rm{m}}},{{\rm{\omega }}}_{{\rm{b}}},h,{n}_{s},{\sigma }_{8},{m}_{\nu },w\}$ hyperplane. at a single redshift, the simulations contain more than 8.5 trillion particles over a comb... | the quijote simulations |
we construct a holographic dark energy scenario based on kaniadakis entropy, which is a generalization of boltzmann-gibbs entropy that arises from relativistic statistical theory and is characterized by a single parameter k which quantifies the deviations from standard expressions, and we use the future event horizon a... | kaniadakis holographic dark energy and cosmology |
the third catalog of active galactic nuclei (agns) detected by the fermi-lat (3lac) is presented. it is based on the third fermi-lat catalog (3fgl) of sources detected between 100 mev and 300 gev with a test statistic greater than 25, between 2008 august 4 and 2012 july 31. the 3lac includes 1591 agns located at high g... | the third catalog of active galactic nuclei detected by the fermi large area telescope |
we present volume-averaged neutral hydrogen fractions $x_{\rm \hi}$ and ionized bubble radii $r_{\rm b}$ measured with ly$\alpha$ damping wing absorption of galaxies at the epoch of reionization. we combine jwst/nirspec spectra taken by ceers, go-1433, ddt-2750, and jades programs, and obtain a sample containing 26 bri... | jwst measurements of neutral hydrogen fractions and ionized bubble sizes at $z=7-12$ obtained with ly$\\alpha$ damping wing absorptions in 26 bright continuum galaxies |
the lofar two-metre sky survey (lotss) is a deep 120-168 mhz imaging survey that will eventually cover the entire northern sky. each of the 3170 pointings will be observed for 8 h, which, at most declinations, is sufficient to produce 5″ resolution images with a sensitivity of 100 μjy/beam and accomplish the main scien... | the lofar two-metre sky survey. i. survey description and preliminary data release |
this paper introduces colossus, a public, open-source python package for calculations related to cosmology, the large-scale structure (lss) of matter in the universe, and the properties of dark matter halos. the code is designed to be fast and easy to use, with a coherent, well-documented user interface. the cosmology ... | colossus: a python toolkit for cosmology, large-scale structure, and dark matter halos |
we develop a general approach to distill symbolic representations of a learned deep model by introducing strong inductive biases. we focus on graph neural networks (gnns). the technique works as follows: we first encourage sparse latent representations when we train a gnn in a supervised setting, then we apply symbolic... | discovering symbolic models from deep learning with inductive biases |
we report a reanalysis of a near-pristine absorption system, located at a redshift {z}abs}=2.52564 toward the quasar q1243+307, based on the combination of archival and new data obtained with the hires echelle spectrograph on the keck telescope. this absorption system, which has an oxygen abundance [o/h] = -2.769 ± 0.0... | one percent determination of the primordial deuterium abundance |
we present limits on spin-independent dark matter-nucleon interactions using a 10.6 g si athermal phonon detector with a baseline energy resolution of σe=3.86 ±0.04 (stat )-0.00+0.19(syst ) ev . this exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic d... | light dark matter search with a high-resolution athermal phonon detector operated above ground |
high-energy cosmic-ray electrons and positrons (cres), which lose energy quickly during their propagation, provide a probe of galactic high-energy processes and may enable the observation of phenomena such as dark-matter particle annihilation or decay. the cre spectrum has been measured directly up to approximately 2 t... | direct detection of a break in the teraelectronvolt cosmic-ray spectrum of electrons and positrons |
we present a detailed exposition on the prospects of the formation of primordial black holes (pbhs) during slow roll (sr) to ultra slow roll (usr) sharp transitions in the framework of single-field inflation. we use an effective field theory (eft) approach in order to keep the analysis model-independent and applicable ... | quantum loop effects on the power spectrum and constraints on primordial black holes |
we present an overview of scenarios where the observed dark matter (dm) abundance consists of feebly interacting massive particles (fimps), produced nonthermally by the so-called freeze-in mechanism. in contrast to the usual freeze-out scenario, frozen-in fimp dm interacts very weakly with the particles in the visible ... | the dawn of fimp dark matter: a review of models and constraints |
the north american nanohertz observatory for gravitational waves has recently reported strong evidence for a stochastic common-spectrum process affecting the pulsar timing residuals in its 12.5-year data set. we demonstrate that this process admits an interpretation in terms of a stochastic gravitational-wave backgroun... | has nanograv found first evidence for cosmic strings? |
the event horizon telescope (eht) collaboration has recently released the first image of a black hole (bh), opening a new window onto tests of general relativity in the strong field regime. in this paper, we derive constraints on the nature of m87* (the supermassive object at the center of the galaxy m87), exploiting t... | testing the rotational nature of the supermassive object m87* from the circularity and size of its first image |
speed matters. how the masses and spins of new particles active during inflation can be read off from the statistical properties of primordial density fluctuations is well understood. however, not when the propagation speeds of the new degrees of freedom and of the curvature perturbation differ, which is the generic si... | cosmological bootstrap in slow motion |
active galactic nuclei (agn) are energetic astrophysical sources powered by accretion onto supermassive black holes in galaxies, and present unique observational signatures that cover the full electromagnetic spectrum over more than twenty orders of magnitude in frequency. the rich phenomenology of agn has resulted in ... | active galactic nuclei: what's in a name? |
we present a comprehensive review of kev-scale sterile neutrino dark matter, collecting views and insights from all disciplines involved—cosmology, astrophysics, nuclear, and particle physics—in each case viewed from both theoretical and experimental/observational perspectives. after reviewing the role of active neutri... | a white paper on kev sterile neutrino dark matter |
this paper presents the high frequency instrument (hfi) data processing procedures for the planck 2018 release. major improvements in mapmaking have been achieved since the previous planck 2015 release, many of which were used and described already in an intermediate paper dedicated to the planck polarized data at low ... | planck 2018 results. iii. high frequency instrument data processing and frequency maps |
we show that polar materials are excellent targets for direct detection of sub-gev dark matter due to the presence of gapped optical phonons as well as acoustic phonons with high sound speed. we take the example of gallium arsenide (gaas), which has the properties needed for experimental realization, and where many res... | detection of light dark matter with optical phonons in polar materials |
the observation of the global 21 cm signal produced by neutral hydrogen gas in the intergalactic medium (igm) during the dark ages, cosmic dawn, and epoch of reionization requires measurements with extremely well-calibrated wideband radiometers. we describe the design and characterization of the mapper of the igm spin ... | mapper of the igm spin temperature (mist): instrument overview |
within the friedmann-lemaître-robertson-walker (flrw) framework, the hubble constant $h_0$ is an integration constant. thus, mathematical consistency demands that $h_0$ is also observationally a constant. building on earlier results, we demonstrate redshift evolution of flat $\lambda$cdm cosmological parameters $(h_0, ... | negative dark energy density from high redshift pantheon+ supernovae |
the violation of the null energy condition (nec) is closely related to potential solutions for the cosmological singularity problem and may therefore play a crucial role in the very early universe. we explore a novel approach to generate primordial black holes (pbhs) via the violation of the nec in a single-field infla... | primordial black holes from null energy condition violation during inflation |
strong evidence for a gravitational-wave background (gwb) has been reported in the nano-hertz band. interpreting the origin of this background to be scalar-induced gravitational waves (sigws), we explore the equation of state (eos) of the early universe by performing bayes parameter inferences across the big-bang nucle... | exploring the equation of state of the early universe: insights from bbn, cmb, and pta observations |
we use a formalism that describes electron ejections from graphenelike targets by dark matter (dm) scattering for general forms of scalar and spin-1/2 dm-electron interactions in combination with state-of-the-art density functional calculations to produce predictions and reach estimates for various possible carbon-base... | direct searches for general dark matter-electron interactions with graphene detectors: part ii. sensitivity studies |
evidence for a low-frequency stochastic gravitational-wave background has recently been reported based on analyses of pulsar timing array data. the most likely source of such a background is a population of supermassive black hole binaries, the loudest of which may be individually detected in these data sets. here we p... | the nanograv 15 yr data set: bayesian limits on gravitational waves from individual supermassive black hole binaries |
we present an initial design study for ldmx, the light dark matter experiment, a small-scale accelerator experiment having broad sensitivity to both direct dark matter and mediator particle production in the sub-gev mass region. ldmx employs missing momentum and energy techniques in multi-gev electro-nuclear fixed-targ... | light dark matter experiment (ldmx) |
we observed the afterglow of the extremely bright grb221009a (dichiara et al., gcn 32632; kennea & williams, gcn 32635; bissaldi et al., gcn 32637; veres et al., gcn 32636; lesage et al., gcn 32642) with x-shooter at eso's ut3 of the very large telescope (paranal, chile). the observations started at 00:49:58.9 ut (... | grb 221009a: redshift from x-shooter/vlt |
active galactic nuclei (agns) represent the growth phases of the supermassive black holes in the center of almost every galaxy. powerful, highly ionized winds, with velocities â¼0.1-0.2c, are a common feature in x-ray spectra of luminous agns, offering a plausible physical origin for the well-known connections between ... | powerful outflows and feedback from active galactic nuclei |
we present a catalog of galaxy clusters selected via their sunyaev-zel'dovich (sz) effect signature from 2500 deg2 of south pole telescope (spt) data. this work represents the complete sample of clusters detected at high significance in the 2500 deg2 spt-sz survey, which was completed in 2011. a total of 677 (409) clus... | galaxy clusters discovered via the sunyaev-zel'dovich effect in the 2500-square-degree spt-sz survey |
hawking evaporation of black holes in the early universe is expected to copiously produce all kinds of particles, regardless of their charges under the standard model gauge group. for this reason, any fundamental particle, known or otherwise, could be produced during the black hole lifetime. this certainly includes dar... | primordial black hole evaporation and dark matter production. i. solely hawking radiation |
we present the catalog of ∼31,500 extragalactic h i line sources detected by the completed arecibo legacy fast alfa (alfalfa) survey out to z < 0.06, including both high signal-to-noise ratio (>6.5) detections and ones of lower quality that coincide in both position and recessional velocity with galaxies of known... | the arecibo legacy fast alfa survey: the alfalfa extragalactic h i source catalog |
we present the temperature and polarization angular power spectra of the cmb measured by the atacama cosmology telescope (act) from 5400 deg2 of the 2013-2016 survey, which covers >15000 deg2 at 98 and 150 ghz. for this analysis we adopt a blinding strategy to help avoid confirmation bias and, related to this, show ... | the atacama cosmology telescope: a measurement of the cosmic microwave background power spectra at 98 and 150 ghz |
we propose the use of silicon carbide (sic) for direct detection of sub-gev dark matter. sic has properties similar to both silicon and diamond but has two key advantages: (i) it is a polar semiconductor which allows sensitivity to a broader range of dark matter candidates; and (ii) it exists in many stable polymorphs ... | silicon carbide detectors for sub-gev dark matter |
we test the statistical isotropy and gaussianity of the cosmic microwave background (cmb) anisotropies using observations made by the planck satellite. our results are based mainly on the full planck mission for temperature, but also include some polarization measurements. in particular, we consider the cmb anisotropy ... | planck 2015 results. xvi. isotropy and statistics of the cmb |
we present the cosmological analysis of the configuration-space anisotropic clustering in the completed sloan digital sky survey iv extended baryon oscillation spectroscopic survey (eboss) data release 16 galaxy sample. this sample consists of luminous red galaxies (lrgs) spanning the redshift range 0.6 < $z$ < 1... | the completed sdss-iv extended baryon oscillation spectroscopic survey: measurement of the bao and growth rate of structure of the luminous red galaxy sample from the anisotropic correlation function between redshifts 0.6 and 1 |
cosmic neutrinos provide a unique window into the otherwise hidden mechanism of particle acceleration in astrophysical objects. the icecube collaboration recently reported the likely association of one high-energy neutrino with a flare from the relativistic jet of an active galaxy pointed towards the earth. however a c... | a tidal disruption event coincident with a high-energy neutrino |
in the framework of metric-affine gravity, we consider the role of the boundary term in symmetric teleparallel gravity assuming f(q, b) models where f is a smooth function of the non-metricity scalar q and the related boundary term b. starting from a variational approach, we derive the field equations and compare them ... | the role of the boundary term in f(q, b) symmetric teleparallel gravity |
the difference from 4 to 6 σ in the hubble constant (h0) between the values observed with the local (cepheids and supernovae ia, sne ia) and the high-z probes (cosmic microwave background obtained by the planck data) still challenges the astrophysics and cosmology community. previous analysis has shown that there is an... | on the evolution of the hubble constant with the sne ia pantheon sample and baryon acoustic oscillations: a feasibility study for grb-cosmology in 2030 |
we investigate modified theories of gravity in the context of teleparallel geometries. it is well known that modified gravity models based on the torsion scalar are not invariant under local lorentz transformations while modifications based on the ricci scalar are. this motivates the study of a model depending on the t... | modified teleparallel theories of gravity |
in this paper, we describe the system design and capabilities of the australian square kilometre array pathfinder (askap) radio telescope at the conclusion of its construction project and commencement of science operations. askap is one of the first radio telescopes to deploy phased array feed (paf) technology on a lar... | australian square kilometre array pathfinder: i. system description |
we show that one-loop corrections to the large-scale power spectrum from small-scale modes in non-slow-roll dynamics are always negligible, namely they are volume suppressed by the ratio of the short to long distance scales. one-loop contributions proportional to the long wavelength tree-level power spectrum, and not s... | absence of one-loop effects on large scales from small scales in non-slow-roll dynamics |
we propose a mellin space approach to the evaluation of late-time momentum-space correlation functions of quantum fields in (d + 1)-dimensional de sitter space. the mellin-barnes representation makes manifest the analytic structure of late-time correlators and, more generally, provides a convenient general d framework ... | a mellin space approach to cosmological correlators |
we summarize the properties and initial data release of the jades origins field (jof), which will soon be the deepest imaging field yet observed with the james webb space telescope (jwst). this field falls within the goods-s region about 8' south-west of the hubble ultra deep field (hudf), where it was formed initially... | the jades origins field: a new jwst deep field in the jades second nircam data release |
we derive cosmological constraints using a galaxy cluster sample selected from the 2500 deg2 spt-sz survey. the sample spans the redshift range 0.25 < z < 1.75 and contains 343 clusters with sz detection significance ξ > 5. the sample is supplemented with optical weak gravitational lensing measurements of 32 c... | cluster cosmology constraints from the 2500 deg2 spt-sz survey: inclusion of weak gravitational lensing data from magellan and the hubble space telescope |
a flat friedmann-robertson-walker universe dominated by a cosmological constant (λ) and cold dark matter (cdm) has been the working model preferred by cosmologists since the discovery of cosmic acceleration1,2. however, tensions of various degrees of significance are known to be present among existing datasets within t... | dynamical dark energy in light of the latest observations |
we study the imprints of massive particles with spin on cosmological correlators. using the framework of the effective field theory of inflation, we classify the couplings of these particles to the goldstone boson of broken time translations and the graviton. we show that it is possible to generate observable non-gauss... | non-gaussianity as a particle detector |
we review inflationary cosmology in modified gravity such as r2 gravity with its extensions in order to generalize the starobinsky inflation model. in particular, we explore inflation realized by three kinds of effects: modification of gravity, the quantum anomaly, and the r2 term in loop quantum cosmology. it is expli... | inflationary cosmology in modified gravity theories |
we assess the status of big-bang nucleosynthesis (bbn) in light of the final planck data release and other recent developments, and in anticipation of future measurements. planck data from the recombination era fix the cosmic baryon density to 0.9% precision, and now damping tail measurements determine the helium abund... | big-bang nucleosynthesis after planck |
we show an inconsistence of the novel 4d einstein-gauss-bonnet gravity by considering a quantum tunneling process of vacua. based on standard semiclassical techniques, we find a nonperturbative way to the study of the vacuum decay rate of the theory. we analytically compute all allowed cases in the parameter space. it ... | vacua in novel 4d einstein-gauss-bonnet gravity: pathology and instability? |
we present a modified cosmological scenario that arises from the application of non-extensive thermodynamics with varying exponent. we extract the modified friedmann equations, which contain new terms quantified by the non-extensive exponent, possessing standard λ cdm cosmology as a subcase. concerning the universe evo... | modified cosmology from extended entropy with varying exponent |
we report constraints on sub-gev dark matter particles interacting with electrons from the first underground operation of damic-m detectors. the search is performed with an integrated exposure of 85.23 g days, and exploits the subelectron charge resolution and low level of dark current of damic-m charge-coupled devices... | first constraints from damic-m on sub-gev dark-matter particles interacting with electrons |
we present a comprehensive analysis of the $\lambda_{\rm s}$cdm model, which explores the recent conjecture suggesting a rapid transition of the universe from anti-de sitter vacua to de sitter vacua (viz., the cosmological constant switches sign from negative to positive) at redshift ${z_\dagger\sim 2}$, inspired by th... | $\\lambda_{\\rm s}$cdm model: a promising scenario for alleviation of cosmological tensions |
the stochastic signal detected by nanograv, ppta, epta, and cpta can be explained by the scalar-induced gravitational waves. in order to determine the scalar-induced gravitational waves model that best fits the stochastic signal, we employ both single- and double-peak parameterizations for the power spectrum of the pri... | constraints on primordial curvature power spectrum with pulsar timing arrays |
models where dark matter and dark energy interact with each other have been proposed to solve the coincidence problem. we review the motivations underlying the need to introduce such interaction, its influence on the background dynamics and how it modifies the evolution of linear perturbations. we test models using the... | dark matter and dark energy interactions: theoretical challenges, cosmological implications and observational signatures |
self-interacting dark matter (sidm) arises generically in scenarios for physics beyond the standard model that have dark sectors with light mediators or strong dynamics. the self-interactions allow energy and momentum transport through halos, altering their structure and dynamics relative to those produced by collision... | astrophysical tests of dark matter self-interactions |
the cresst experiment is a direct dark matter search which aims to measure interactions of potential dark matter particles in an earth-bound detector. with the current stage, cresst-iii, we focus on a low energy threshold for increased sensitivity towards light dark matter particles. in this manuscript we describe the ... | first results from the cresst-iii low-mass dark matter program |
the xenon1t experiment at the laboratori nazionali del gran sasso (lngs) is the first wimp dark matter detector operating with a liquid xenon target mass above the ton-scale. out of its 3.2 t liquid xenon inventory, 2.0 t constitute the active target of the dual-phase time projection chamber. the scintillation and ioni... | the xenon1t dark matter experiment |
recently, aligo announced the first direct detections of gravitational waves, a direct manifestation of the propagating degrees of freedom of gravity. the detected signals gw150914 and gw151226 have been used to examine the basic properties of these gravitational degrees of freedom, particularly setting an upper bound ... | graviton mass bounds |
we critically examine the magnitude of theoretical uncertainties in perturbative calculations of fist-order phase transitions, using the standard model effective field theory as our guide. in the usual daisy-resummed approach, we find large uncertainties due to renormalisation scale dependence, which amount to two to t... | theoretical uncertainties for cosmological first-order phase transitions |
cosmography can be considered as a sort of a model-independent approach to tackle the dark energy/modified gravity problem. in this review, the success and the shortcomings of the λcdm model, based on general relativity (gr) and standard model of particles, are discussed in view of the most recent observational constra... | extended gravity cosmography |
we present a detailed investigation of a subdominant oscillating scalar field ["early dark energy" (ede)] in the context of resolving the hubble tension. consistent with earlier work, but without relying on fluid approximations, we find that a scalar field frozen due to hubble friction until log10(zc)∼3.5 , reaching ρe... | oscillating scalar fields and the hubble tension: a resolution with novel signatures |
frb 121102 is the only known repeating fast radio burst source. here we analyze a wide-frequency-range (1-8 ghz) sample of high signal-to-noise, coherently dedispersed bursts detected using the arecibo and green bank telescopes. these bursts reveal complex time-frequency structures that include subbursts with finite ba... | frb 121102 bursts show complex time-frequency structure |
we outline the experimental concept and key scientific capabilities of aion (atom interferometer observatory and network), a proposed experimental programme using cold strontium atoms to search for ultra-light dark matter, to explore gravitational waves in the mid-frequency range between the peak sensitivities of the l... | aion: an atom interferometer observatory and network |
we present a novel theory of gravity by considering an extension of symmetric teleparallel gravity. this is done by introducing, in the framework of the metric-affine formalism, a new class of theories where the nonmetricity q is nonminimally coupled to the matter lagrangian. more specifically, we consider a lagrangian... | coupling matter in modified q gravity |
we present constraints on the masses of extremely light bosons dubbed fuzzy dark matter (fdm) from lyman-α forest data. extremely light bosons with a de broglie wavelength of ∼1 kpc have been suggested as dark matter candidates that may resolve some of the current small scale problems of the cold dark matter model. for... | first constraints on fuzzy dark matter from lyman-α forest data and hydrodynamical simulations |
several pulsar timing array (pta) collaborations, including nanograv, epta, ppta, and cpta, have announced the evidence for a stochastic signal consistent with a stochastic gravitational wave background (sgwb). supermassive black hole binaries (smbhbs) are supposed to be the most promising gravitational-wave (gw) sourc... | implications for the supermassive black hole binaries from the nanograv 15-year data set |
if even a relatively small number of black holes were created in the early universe, they will constitute an increasingly large fraction of the total energy density as space expands. it is thus well-motivated to consider scenarios in which the early universe included an era in which primordial black holes dominated the... | dark radiation and superheavy dark matter from black hole domination |
we present evidence for a suppressed growth rate of large-scale structure during the dark-energy-dominated era. modeling the growth rate of perturbations with the "growth index" γ , we find that current cosmological data strongly prefer a higher growth index than the value γ =0.55 predicted by general relativity in a f... | evidence for suppression of structure growth in the concordance cosmological model |
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