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we report on the implications for cosmic inflation of the 2018 release of the planck cosmic microwave background (cmb) anisotropy measurements. the results are fully consistent with those reported using the data from the two previous planck cosmological releases, but have smaller uncertainties thanks to improvements in...
planck 2018 results. x. constraints on inflation
gaia is a cornerstone mission in the science programme of the europeanspace agency (esa). the spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. both the spacecraft and the payload were built by european industry. the i...
the gaia mission
we systematically review some standard issues and also the latest developments of modified gravity in cosmology, emphasizing on inflation, bouncing cosmology and late-time acceleration era. particularly, we present the formalism of standard modified gravity theory representatives, like f(r) , f(g) and f(t) gravity theo...
modified gravity theories on a nutshell: inflation, bounce and late-time evolution
when surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture at the event horizon. to image and study this phenomenon, we have assembled the event horizon telescope, a global very long baseline interferometry array observing ...
first m87 event horizon telescope results. i. the shadow of the supermassive black hole
the european pulsar timing array (epta) and indian pulsar timing array (inpta) collaborations have measured a low-frequency common signal in the combination of their second and first data releases respectively, with the correlation properties of a gravitational wave background (gwb). such signal may have its origin in ...
the second data release from the european pulsar timing array: v. implications for massive black holes, dark matter and the early universe
pulsar timing arrays aim to detect nanohertz-frequency gravitational waves (gws). a background of gws modulates pulsar arrival times and manifests as a stochastic process, common to all pulsars, with a signature spatial correlation. here we describe a search for an isotropic stochastic gravitational-wave background (gw...
search for an isotropic gravitational-wave background with the parkes pulsar timing array
we present the results of the search for an isotropic stochastic gravitational wave background (gwb) at nanohertz frequencies using the second data release of the european pulsar timing array (epta) for 25 millisecond pulsars and a combination with the first data release of the indian pulsar timing array (inpta). a rob...
the second data release from the european pulsar timing array. iii. search for gravitational wave signals
desi (dark energy spectroscopic instrument) is a stage iv ground-based dark energy experiment that will study baryon acoustic oscillations (bao) and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. to trace the underlying dark matter distribution, spectrosco...
the desi experiment part i: science,targeting, and survey design
the lux-zeplin experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the sanford underground research facility in lead, south dakota, usa. this letter reports results from lux-zeplin's first search for weakly interacting massive particles (wimps) with an exposure of 60...
first dark matter search results from the lux-zeplin (lz) experiment
machine learning (ml) encompasses a broad range of algorithms and modeling tools used for a vast array of data processing tasks, which has entered most scientific disciplines in recent years. this article reviews in a selective way the recent research on the interface between machine learning and the physical sciences....
machine learning and the physical sciences*
we report observations from the hubble space telescope (hst) of cepheid variables in the host galaxies of 42 type ia supernovae (sne ia) used to calibrate the hubble constant (h 0). these include the complete sample of all suitable sne ia discovered in the last four decades at redshift z ≤ 0.01, collected and calibrate...
a comprehensive measurement of the local value of the hubble constant with 1 km s-1 mpc-1 uncertainty from the hubble space telescope and the sh0es team
we report constraints on spin-independent weakly interacting massive particle (wimp)-nucleon scattering using a 3.35 ×1 04 kg day exposure of the large underground xenon (lux) experiment. a dual-phase xenon time projection chamber with 250 kg of active mass is operated at the sanford underground research facility under...
results from a search for dark matter in the complete lux exposure
the simplest λcdm model provides a good fit to a large span of cosmological data but harbors large areas of phenomenology and ignorance. with the improvement of the number and the accuracy of observations, discrepancies among key cosmological parameters of the model have emerged. the most statistically significant tens...
in the realm of the hubble tension-a review of solutions
this book lays out the scientific goals to be addressed by the next-generation ground-based cosmic microwave background experiment, cmb-s4, envisioned to consist of dedicated telescopes at the south pole, the high chilean atacama plateau and possibly a northern hemisphere site, all equipped with new superconducting cam...
cmb-s4 science book, first edition
the 15 yr pulsar timing data set collected by the north american nanohertz observatory for gravitational waves (nanograv) shows positive evidence for the presence of a low-frequency gravitational-wave (gw) background. in this paper, we investigate potential cosmological interpretations of this signal, specifically cosm...
the nanograv 15 yr data set: search for signals from new physics
the european space agency's planck satellite, which was dedicated to studying the early universe and its subsequent evolution, was launched on 14 may 2009. it scanned the microwave and submillimetre sky continuously between 12 august 2009 and 23 october 2013, producing deep, high-resolution, all-sky maps in nine freque...
planck 2018 results. i. overview and the cosmological legacy of planck
we present cosmological results from the final galaxy clustering data set of the baryon oscillation spectroscopic survey, part of the sloan digital sky survey iii. our combined galaxy sample comprises 1.2 million massive galaxies over an effective area of 9329 deg2 and volume of 18.7 gpc3, divided into three partially ...
the clustering of galaxies in the completed sdss-iii baryon oscillation spectroscopic survey: cosmological analysis of the dr12 galaxy sample
we report on a search for weakly interacting massive particles (wimps) using 278.8 days of data collected with the xenon1t experiment at lngs. xenon1t utilizes a liquid xenon time projection chamber with a fiducial mass of (1.30 ±0.01 ) t o n , resulting in a 1.0 ton yr exposure. the energy region of interest, [1.4 ,10...
dark matter search results from a one ton-year exposure of xenon1t
we present optical light curves, redshifts, and classifications for 365 spectroscopically confirmed type ia supernovae (sne ia) discovered by the pan-starrs1 (ps1) medium deep survey. we detail improvements to the ps1 sn photometry, astrometry, and calibration that reduce the systematic uncertainties in the ps1 sn ia d...
the complete light-curve sample of spectroscopically confirmed sne ia from pan-starrs1 and cosmological constraints from the combined pantheon sample
we update the constraints on the fraction of the universe that may have gone into primordial black holes (pbhs) over the mass range 10-5 to 1050 g. those smaller than ~1015 g would have evaporated by now due to hawking radiation, so their abundance at formation is constrained by the effects of evaporated particles on b...
constraints on primordial black holes
we present the implications for cosmic inflation of the planck measurements of the cosmic microwave background (cmb) anisotropies in both temperature and polarization based on the full planck survey, which includes more than twice the integration time of the nominal survey used for the 2013 release papers. the planck f...
planck 2015 results. xx. constraints on inflation
we present an updated global fit of neutrino oscillation data in the simplest three-neutrino framework. in the present study we include up-to-date analyses from a number of experiments. concerning the atmospheric and solar sectors, besides the data considered previously, we give updated analyses of icecube deepcore and...
2020 global reassessment of the neutrino oscillation picture
advanced virgo is the project to upgrade the virgo interferometric detector of gravitational waves, with the aim of increasing the number of observable galaxies (and thus the detection rate) by three orders of magnitude. the project is now in an advanced construction phase and the assembly and integration will be compl...
advanced virgo: a second-generation interferometric gravitational wave detector
we study whether the signal seen by pulsar timing arrays (ptas) may originate from gravitational waves (gws) induced by large primordial perturbations. such perturbations may be accompanied by a sizable primordial black hole (pbh) abundance. we improve existing analyses and show that pbh overproduction disfavors gaussi...
recent gravitational wave observation by pulsar timing arrays and primordial black holes: the importance of non-gaussianities
we present the first cosmology results from large-scale structure using the full 5000 deg2 of imaging data from the dark energy survey (des) data release 1. we perform an analysis of large-scale structure combining three two-point correlation functions (3 ×2 pt ): (i) cosmic shear using 100 million source galaxies, (ii...
dark energy survey year 3 results: cosmological constraints from galaxy clustering and weak lensing
monte carlo techniques, including mcmc and other methods, are widely used and generate sets of samples from a parameter space of interest that can be used to infer or plot quantities of interest. this note outlines methods used the python getdist package to calculate marginalized one and two dimensional densities using...
getdist: a python package for analysing monte carlo samples
the standard λ cold dark matter (λcdm) cosmological model provides a good description of a wide range of astrophysical and cosmological data. however, there are a few big open questions that make the standard model look like an approximation to a more realistic scenario yet to be found. in this paper, we list a few imp...
cosmology intertwined: a review of the particle physics, astrophysics, and cosmology associated with the cosmological tensions and anomalies
the recently introduced swampland criterion for de sitter [17] can be viewed as a (hierarchically large) bound on the smallness of the slow roll parameter 𝜖v. this leads us to consider the other slow roll parameter ηv more closely, and we are lead to conjecture that the bound is not necessarily on 𝜖v, but on slow rol...
bounds on slow roll and the de sitter swampland
we present a measurement of the hubble constant (h0) and other cosmological parameters from a joint analysis of six gravitationally lensed quasars with measured time delays. all lenses except the first are analysed blindly with respect to the cosmological parameters. in a flat λ cold dark matter (λcdm) cosmology, we fi...
h0licow - xiii. a 2.4 per cent measurement of h0 from lensed quasars: 5.3σ tension between early- and late-universe probes
despite the remarkable success of the λ cold dark matter (λcdm) cosmological model, a growing discrepancy has emerged (currently measured at the level of ∼ 4 - 6 σ) between the value of the hubble constant h0 measured using the local distance ladder and the value inferred using the cosmic microwave background and galax...
the h0 olympics: a fair ranking of proposed models
we present the science case, reference design, and project plan for the stage-4 ground-based cosmic microwave background experiment cmb-s4.
cmb-s4 science case, reference design, and project plan
teleparallel gravity (tg) has significantly increased in popularity in recent decades, bringing attention to einstein's other theory of gravity. in this review, we give a comprehensive introduction to how teleparallel geometry is developed as a gauge theory of translations together with all the other properties of gaug...
teleparallel gravity: from theory to cosmology
we present the cosmological implications from final measurements of clustering using galaxies, quasars, and ly α forests from the completed sloan digital sky survey (sdss) lineage of experiments in large-scale structure. these experiments, composed of data from sdss, sdss-ii, boss, and eboss, offer independent measurem...
completed sdss-iv extended baryon oscillation spectroscopic survey: cosmological implications from two decades of spectroscopic surveys at the apache point observatory
we present the fourth fermi large area telescope catalog (4fgl) of γ-ray sources. based on the first eight years of science data from the fermi gamma-ray space telescope mission in the energy range from 50 mev to 1 tev, it is the deepest yet in this energy range. relative to the 3fgl catalog, the 4fgl catalog has twice...
fermi large area telescope fourth source catalog
we report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (wimps) with the xenonnt experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. during the (1.09 ±0.03 ) ton yr exposure used for this search, ...
first dark matter search with nuclear recoils from the xenonnt experiment
we use the wide field camera 3 (wfc3) on the hubble space telescope (hst) to reduce the uncertainty in the local value of the hubble constant from 3.3% to 2.4%. the bulk of this improvement comes from new near-infrared (nir) observations of cepheid variables in 11 host galaxies of recent type ia supernovae (sne ia), mo...
a 2.4% determination of the local value of the hubble constant
among swampland conditions, the distance conjecture characterizes the geometry of scalar fields and the de sitter conjecture constrains allowed potentials on it. we point out a connection between the distance conjecture and a refined version of the de sitter conjecture in any parametrically controlled regime of string ...
distance and de sitter conjectures on the swampland
multiple theories have been proposed to describe the formation of black hole seeds in the early universe and to explain the emergence of very massive black holes observed in the first billion years after big bang. models consider different seeding and accretion scenarios, which require the detection and characterisatio...
a small and vigorous black hole in the early universe
the recently released data by pulsar timing array (pta) collaborations present strong evidence for a stochastic signal consistent with a gravitational-wave background. assuming this signal originates from scalar-induced gravitational waves, we jointly use the pta data from the nanograv 15-yr data set, ppta dr3, and ept...
implications for the non-gaussianity of curvature perturbation from pulsar timing arrays
we present results from an analysis of all data taken by the bicep2, keck array, and bicep3 cmb polarization experiments up to and including the 2018 observing season. we add additional keck array observations at 220 ghz and bicep3 observations at 95 ghz to the previous 95 /150 /220 ghz dataset. the q /u maps now reach...
improved constraints on primordial gravitational waves using planck, wmap, and bicep/keck observations through the 2018 observing season
we search for an isotropic stochastic gravitational-wave background (gwb) in the 12.5 yr pulsar-timing data set collected by the north american nanohertz observatory for gravitational waves. our analysis finds strong evidence of a stochastic process, modeled as a power law, with common amplitude and spectral slope acro...
the nanograv 12.5 yr data set: search for an isotropic stochastic gravitational-wave background
accordingly, by performing the 2-point correlation of hk (τ) which is proportional to the correlator of scalar source sk (τ), one can arrive at the power spectrum of igws during rd:
limits on scalar-induced gravitational waves from the stochastic background by pulsar timing array observations
we describe the legacy planck cosmic microwave background (cmb) likelihoods derived from the 2018 data release. the overall approach is similar in spirit to the one retained for the 2013 and 2015 data release, with a hybrid method using different approximations at low (ℓ < 30) and high (ℓ ≥ 30) multipoles, implement...
planck 2018 results. v. cmb power spectra and likelihoods
we present an overview of the james webb space telescope (jwst) advanced deep extragalactic survey (jades), an ambitious program of infrared imaging and spectroscopy in the goods-s and goods-n deep fields, designed to study galaxy evolution from high redshift to cosmic noon. jades uses about 770 hours of cycle 1 guaran...
overview of the jwst advanced deep extragalactic survey (jades)
after a decade and a half of research motivated by the accelerating universe, theory and experiment have reached a certain level of maturity. the development of theoretical models beyond λ or smooth dark energy, often called modified gravity, has led to broader insights into a path forward, and a host of observational ...
beyond the cosmological standard model
we present measurements of the properties of the central radio source in m87 using event horizon telescope data obtained during the 2017 campaign. we develop and fit geometric crescent models (asymmetric rings with interior brightness depressions) using two independent sampling algorithms that consider distinct represe...
first m87 event horizon telescope results. vi. the shadow and mass of the central black hole
the observation of gw170817 and its electromagnetic counterpart implies that gravitational waves travel at the speed of light, with deviations smaller than a few ×10-15 . we discuss the consequences of this experimental result for models of dark energy and modified gravity characterized by a single scalar degree of fre...
dark energy after gw170817 and grb170817a
this white paper summarizes the workshop "u.s. cosmic visions: new ideas in dark matter" held at university of maryland on march 23-25, 2017.
us cosmic visions: new ideas in dark matter 2017: community report
a number of challenges to the standard λcdm model have been emerging during the past few years as the accuracy of cosmological observations improves. in this review we discuss in a unified manner many existing signals in cosmological and astrophysical data that appear to be in some tension (2 σ or larger) with the stan...
challenges for λcdm: an update
the desi legacy imaging surveys (http://legacysurvey.org/) are a combination of three public projects (the dark energy camera legacy survey, the beijing-arizona sky survey, and the mayall z-band legacy survey) that will jointly image ≈14,000 deg2 of the extragalactic sky visible from the northern hemisphere in three op...
overview of the desi legacy imaging surveys
the nanograv 15 yr data set shows evidence for the presence of a low-frequency gravitational-wave background (gwb). while many physical processes can source such low-frequency gravitational waves, here we analyze the signal as coming from a population of supermassive black hole (smbh) binaries distributed throughout th...
the nanograv 15 yr data set: constraints on supermassive black hole binaries from the gravitational-wave background
we report constraints on light dark matter (dm) models using ionization signals in the xenon1t experiment. we mitigate backgrounds with strong event selections, rather than requiring a scintillation signal, leaving an effective exposure of (22 ±3 ) tonne day. above ∼0.4 keve e , we observe <1 event/(tonne day keve e...
light dark matter search with ionization signals in xenon1t
very recently pulsar timing array (pta) collaborations have independently reported the evidence for a stochastic gravitational-wave background (sgwb), which can unveil the formation of primordial seeds of inhomogeneities in the early universe. with the sgwb parameters inferred from ptas data, we can make a prediction o...
footprints of axion-like particle in pulsar timing array data and jwst observations
a kavli institute for theoretical physics workshop in july 2019 directed attention to the hubble constant discrepancy. new results showed that it does not appear to depend on the use of any one method, team or source. proposed solutions focused on the pre-recombination era.
tensions between the early and late universe
the event horizon telescope (eht) has mapped the central compact radio source of the elliptical galaxy m87 at 1.3 mm with unprecedented angular resolution. here we consider the physical implications of the asymmetric ring seen in the 2017 eht data. to this end, we construct a large library of models based on general re...
first m87 event horizon telescope results. v. physical origin of the asymmetric ring
multiple pulsar-timing-array collaborations have reported strong evidence for the existence of a gravitational-wave background. we study physical implications of this signal for cosmology, assuming that it is attributed to scalar-induced gravitational waves. by incorporating primordial non-gaussianity $f_{\mathrm{nl}}$...
implications of pulsar timing array data for scalar-induced gravitational waves and primordial black holes: primordial non-gaussianity $f_{\\mathrm{nl}}$ considered
in recent years, several pulsar timing array collaborations have reported first hints for a stochastic gravitational wave background at nano-hertz frequencies. here we elaborate on the possibility that this signal comes from new physics that leads to the generation of a primordial stochastic gravitational wave backgrou...
primordial gravitational waves in the nano-hertz regime and pta data — towards solving the gw inverse problem
we present the first event horizon telescope (eht) images of m87, using observations from april 2017 at 1.3 mm wavelength. these images show a prominent ring with a diameter of ∼40 μas, consistent with the size and shape of the lensed photon orbit encircling the “shadow” of a supermassive black hole. the ring is persis...
first m87 event horizon telescope results. iv. imaging the central supermassive black hole
we discuss the interpretation of the detected signal by pulsar timing array (pta) observations as a gravitational wave background (gwb) of cosmological origin. we combine nanograv 15-years and epta-dr2new data sets and confront them against backgrounds from supermassive black hole binaries (smbhbs) and cosmological sig...
cosmological background interpretation of pulsar timing array data
we study for the first time the gravitational waves generated during the collapse of domain walls, incorporating the potential bias in the lattice simulations. the final stages of domain wall collapse are crucial for the production of gravitational waves, but have remained unexplored due to computational difficulties. ...
gravitational waves from domain wall collapse, and application to nanohertz signals with qcd-coupled axions
the simons observatory (so) is a new cosmic microwave background experiment being built on cerro toco in chile, due to begin observations in the early 2020s. we describe the scientific goals of the experiment, motivate the design, and forecast its performance. so will measure the temperature and polarization anisotropy...
the simons observatory: science goals and forecasts
we present cosmological results from a combined analysis of galaxy clustering and weak gravitational lensing, using 1321 deg2 of griz imaging data from the first year of the dark energy survey (des y1). we combine three two-point functions: (i) the cosmic shear correlation function of 26 million source galaxies in four...
dark energy survey year 1 results: cosmological constraints from galaxy clustering and weak lensing
we present an expanded sample of 75 milky way cepheids with hubble space telescope (hst) photometry and gaia edr3 parallaxes, which we use to recalibrate the extragalactic distance ladder and refine the determination of the hubble constant. all hst observations were obtained with the same instrument (wfc3) and filters ...
cosmic distances calibrated to 1% precision with gaia edr3 parallaxes and hubble space telescope photometry of 75 milky way cepheids confirm tension with λcdm
high energy collisions at the high-luminosity large hadron collider (lhc) produce a large number of particles along the beam collision axis, outside of the acceptance of existing lhc experiments. the proposed forward physics facility (fpf), to be located several hundred meters from the atlas interaction point and shiel...
the forward physics facility at the high-luminosity lhc
in this paper, we propose a new swampland condition, the trans-planckian censorship conjecture (tcc), based on the idea that in a consistent quantum theory of gravity sub-planckian quantum fluctuations should remain quantum and never become larger than the hubble horizon and freeze in an expanding universe. applied to ...
trans-planckian censorship and the swampland
we report on the neutrino mass measurement result from the first four-week science run of the karlsruhe tritium neutrino experiment katrin in spring 2019. beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution mac-e filter. a fit of the integrated electron spec...
improved upper limit on the neutrino mass from a direct kinematic method by katrin
context. gaia early data release 3 (gaia edr3) contains astrometry and photometry results for about 1.8 billion sources based on observations collected by the european space agency gaia satellite during the first 34 months of its operational phase.aims: in this paper, we focus on the photometric content, describing the...
gaia early data release 3. photometric content and validation
we present measurements of the cosmic microwave background (cmb) lensing potential using the final planck 2018 temperature and polarization data. using polarization maps filtered to account for the noise anisotropy, we increase the significance of the detection of lensing in the polarization maps from 5σ to 9σ. combine...
planck 2018 results. viii. gravitational lensing
the main objectives of the km3net collaboration are (i) the discovery and subsequent observation of high-energy neutrino sources in the universe and (ii) the determination of the mass hierarchy of neutrinos. these objectives are strongly motivated by two recent important discoveries, namely: (1) the high-energy astroph...
letter of intent for km3net 2.0
aspects of primordial black holes, i.e. black holes formed in the early universe, are reviewed. special emphasis is put on their formation, their r{ô}le as dark matter candidates and their manifold signatures, particularly through gravitational waves.
primordial black holes
we present the third fermi large area telescope (lat) source catalog (3fgl) of sources in the 100 mev-300 gev range. based on the first 4 yr of science data from the fermi gamma-ray space telescope mission, it is the deepest yet in this energy range. relative to the second fermi lat catalog, the 3fgl catalog incorporat...
fermi large area telescope third source catalog
we describe the 2017 release of the spectral synthesis code cloudy, summarizing the many improvements to the scope and accuracy of the physics which have been made since the previous release. exporting the atomic data into external data files has enabled many new large datasets to be incorporated into the code. the use...
the 2017 release cloudy
the einstein telescope (et), a proposed european ground-based gravitational-wave detector of third-generation, is an evolution of second-generation detectors such as advanced ligo, advanced virgo, and kagra which could be operating in the mid 2030s. et will explore the universe with gravitational waves up to cosmologic...
science case for the einstein telescope
we present the first direct-detection search for sub-gev dark matter using a new ∼2 -gram high-resistivity skipper ccd from a dedicated fabrication batch that was optimized for dark matter searches. using 24 days of data acquired in the minos cavern at the fermi national accelerator laboratory, we measure the lowest ra...
sensei: direct-detection results on sub-gev dark matter from a new skipper ccd
we study constraints imposed by two proposed string swampland criteria on cosmology. these criteria involve an upper bound on the range traversed by scalar fields as well as a lower bound on |∇ϕ v | / v when v > 0. we find that inflationary models are generically in tension with these two criteria. applying these sa...
on the cosmological implications of the string swampland
we present a joint cosmological analysis of weak gravitational lensing observations from the kilo-degree survey (kids-1000), with redshift-space galaxy clustering observations from the baryon oscillation spectroscopic survey (boss) and galaxy-galaxy lensing observations from the overlap between kids-1000, boss, and the...
kids-1000 cosmology: multi-probe weak gravitational lensing and spectroscopic galaxy clustering constraints
we present constraints on cosmological parameters from the pantheon+ analysis of 1701 light curves of 1550 distinct type ia supernovae (sne ia) ranging in redshift from z = 0.001 to 2.26. this work features an increased sample size from the addition of multiple cross-calibrated photometric systems of sne covering an in...
the pantheon+ analysis: cosmological constraints
we analyse the planck full-mission cosmic microwave background (cmb) temperature and e-mode polarization maps to obtain constraints on primordial non-gaussianity (ng). we compare estimates obtained from separable template-fitting, binned, and optimal modal bispectrum estimators, finding consistent values for the local,...
planck 2018 results. ix. constraints on primordial non-gaussianity
the dark energy plus cold dark matter (λcdm) cosmological model has been a demonstrably successful framework for predicting and explaining the large-scale structure of the universe and its evolution with time. yet on length scales smaller than ∼1 mpc and mass scales smaller than ∼1011m⊙, the theory faces a number of ch...
small-scale challenges to the λcdm paradigm
over the past decade, the disparity between the value of the cosmic expansion rate determined directly from measurements of distance and redshift and that determined instead from the standard lambda cold dark matter (λcdm) cosmological model, calibrated by measurements from the early universe, has grown to a level of s...
the hubble tension and early dark energy
pulsar timing arrays (ptas) have reported evidence for a stochastic gravitational wave (gw) background at nhz frequencies, possibly originating in the early universe. we show that the spectral shape of the low-frequency (causality) tail of gw signals sourced at temperatures around $t\gtrsim 1$ gev is distinctively affe...
footprints of the qcd crossover on cosmological gravitational waves at pulsar timing arrays
we introduce the illustristng project, a new suite of cosmological magnetohydrodynamical simulations performed with the moving-mesh code arepo employing an updated illustris galaxy formation model. here we focus on the general properties of magnetic fields and the diffuse radio emission in galaxy clusters. magnetic fie...
first results from the illustristng simulations: radio haloes and magnetic fields
although the dark matter is usually assumed to be made up of some form of elementary particle, primordial black holes (pbhs) could also provide some of it. however, various constraints restrict the possible mass windows to 1016–1017 g, 1020–1024 g, and 10–103m⊙. the last possibility is contentious but of special intere...
primordial black holes as dark matter: recent developments
we create a sample of spectroscopically identified galaxies with z < 0.2 from the sloan digital sky survey (sdss) data release 7 (dr7), covering 6813 deg2. galaxies are chosen to sample the highest mass haloes, with an effective bias of 1.5, allowing us to construct 1000 mock galaxy catalogues (described in paper ii...
the clustering of the sdss dr7 main galaxy sample - i. a 4 per cent distance measure at z = 0.15
multiple pulsar timing array (pta) collaborations recently announced the evidence of common-spectral processes caused by gravitational waves (gws). these can be the stochastic gw background and its origin may be astrophysical and/or cosmological. we interpret it as the gws induced by the primordial curvature perturbati...
the detected stochastic gravitational waves and subsolar-mass primordial black holes
the self-interacting dark matter (sidm) paradigm offers a potential solution to small-scale structure problems faced by the collision-less cold dark matter. this framework incorporates self-interactions among dark matter particles, typically mediated by a particle with a mev-scale mass. recent evidences of nano-hertz g...
self-interacting dark matter implied by nano-hertz gravitational waves
pulsar timing arrays offer a probe of the low-frequency gravitational wave spectrum (1-100 nhz), which is intimately connected to a number of markers that can uniquely trace the formation and evolution of the universe. we present the dataset and the results of the timing analysis from the second data release of the eur...
the second data release from the european pulsar timing array. i. the dataset and timing analysis
we present the results of a search for continuous gravitational wave signals (cgws) in the second data release (dr2) of the european pulsar timing array (epta) collaboration. the most significant candidate event from this search has a gravitational wave frequency of 4-5 nhz. such a signal could be generated by a superm...
the second data release from the european pulsar timing array iv. search for continuous gravitational wave signals
we introduce a new class of scalar-tensor theories of gravity that extend horndeski, or "generalized galileon," models. despite possessing equations of motion of higher order in derivatives, we show that the true propagating degrees of freedom obey well-behaved second-order equations and are thus free from ostrogradski...
new class of consistent scalar-tensor theories
this letter reports the results from a haloscope search for dark matter axions with masses between 2.66 and 2.81 μ ev . the search excludes the range of axion-photon couplings predicted by plausible models of the invisible axion. this unprecedented sensitivity is achieved by operating a large-volume haloscope at subkel...
search for invisible axion dark matter with the axion dark matter experiment
the existence of dark matter as evidenced by numerous indirect observations is one of the most important indications that there must be physics beyond the standard model of particle physics. this article reviews the concepts of direct detection of dark matter in the form of weakly interacting massive particles in ultra...
direct detection of wimp dark matter: concepts and status
this report, based on the dark sectors workshop at slac in april 2016, summarizes the scientific importance of searches for dark sector dark matter and forces at masses beneath the weak-scale, the status of this broad international field, the important milestones motivating future exploration, and promising experimenta...
dark sectors 2016 workshop: community report
we review recent trends in inflationary dynamics in the context of viable modified gravity theories. after providing a general overview of the inflationary paradigm emphasizing on what problems hot big bang theory inflation solves, and a somewhat introductory presentation of single-field inflationary theories with mini...
recent advances in inflation
we report the first dark matter search results from xenon1t, a ∼2000 -kg -target-mass dual-phase (liquid-gas) xenon time projection chamber in operation at the laboratori nazionali del gran sasso in italy and the first ton-scale detector of this kind. the blinded search used 34.2 live days of data acquired between nove...
first dark matter search results from the xenon1t experiment
this paper characterizes the actual science performance of the james webb space telescope (jwst), as determined from the six month commissioning period. we summarize the performance of the spacecraft, telescope, science instruments, and ground system, with an emphasis on differences from pre-launch expectations. commis...
the science performance of jwst as characterized in commissioning
early dark energy (ede) that behaves like a cosmological constant at early times (redshifts z ≳3000 ) and then dilutes away like radiation or faster at later times can solve the hubble tension. in these models, the sound horizon at decoupling is reduced resulting in a larger value of the hubble parameter h0 inferred fr...
early dark energy can resolve the hubble tension
the european space agency's planck satellite, which is dedicated to studying the early universe and its subsequent evolution, was launched on 14 may 2009. it scanned the microwave and submillimetre sky continuously between 12 august 2009 and 23 october 2013. in february 2015, esa and the planck collaboration released t...
planck 2015 results. i. overview of products and scientific results
in this work, we present a quintessential interpretation of having a blue-tilted tensor power spectrum for canonical single-field slow-roll inflation to explain the recently observed nanogracv 15-year signal of gravitational waves (gw). we formulate the complete semi-classical description of cosmological perturbation t...
single field inflation in the light of nanograv 15-year data: quintessential interpretation of blue tilted tensor spectrum through non-bunch davies initial condition
the event horizon telescope (eht) is a very long baseline interferometry (vlbi) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the earth. at a nominal operating wavelength of ∼1.3 mm, eht angular resolution (λ/d) is ∼25 μas, which is suffici...
first m87 event horizon telescope results. ii. array and instrumentation
we consider the constraints from supernova 1987a on particles with small couplings to the standard model. we discuss a model with a fermion coupled to a dark photon, with various mass relations in the dark sector; millicharged particles; dark-sector fermions with inelastic transitions; the hadronic qcd axion; and an ax...
supernova 1987a constraints on sub-gev dark sectors, millicharged particles, the qcd axion, and an axion-like particle