Inflationary Imprints on Dark Matter
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Baryogenesis in a CP Invariant Theory That Utilizes the Stochastic Movement of Light fields During Inflation
Baryogenesis in a CP invariant theory Anson Hook School of Natural Sciences Institute for Advanced Study Princeton, NJ 08540 June 12, 2018 Abstract We consider baryogenesis in a model which has a CP invariant Lagrangian, CP invariant initial conditions and does not spontaneously break CP at any of the minima. We utilize the fact that tunneling processes between CP invariant minima can break CP to implement baryogenesis. CP invariance requires the presence of two tunneling processes with opposite CP breaking phases and equal probability of occurring. In order for the entire visible universe to see the same CP violating phase, we consider a model where the field doing the tunneling is the inflaton. arXiv:1508.05094v1 [hep-ph] 20 Aug 2015 1 1 Introduction The visible universe contains more matter than anti-matter [1]. The guiding principles for gener- ating this asymmetry have been Sakharov’s three conditions [2]. These three conditions are C/CP violation • Baryon number violation • Out of thermal equilibrium • Over the years, counter examples have been found for Sakharov’s conditions. One can avoid the need for number violating interactions in theories where the negative B L number is stored − in a sector decoupled from the standard model, e.g. in right handed neutrinos as in Dirac lep- togenesis [3, 4] or in dark matter [5]. The out of equilibrium condition can be avoided if one uses spontaneous baryogenesis [6], where a chemical potential is used to create a non-zero baryon number in thermal equilibrium. However, these models still require a C/CP violating phase or coupling in the Lagrangian. -
Letter of Interest Cosmic Probes of Ultra-Light Axion Dark Matter
Snowmass2021 - Letter of Interest Cosmic probes of ultra-light axion dark matter Thematic Areas: (check all that apply /) (CF1) Dark Matter: Particle Like (CF2) Dark Matter: Wavelike (CF3) Dark Matter: Cosmic Probes (CF4) Dark Energy and Cosmic Acceleration: The Modern Universe (CF5) Dark Energy and Cosmic Acceleration: Cosmic Dawn and Before (CF6) Dark Energy and Cosmic Acceleration: Complementarity of Probes and New Facilities (CF7) Cosmic Probes of Fundamental Physics (TF09) Astro-particle physics and cosmology Contact Information: Name (Institution) [email]: Keir K. Rogers (Oskar Klein Centre for Cosmoparticle Physics, Stockholm University; Dunlap Institute, University of Toronto) [ [email protected]] Authors: Simeon Bird (UC Riverside), Simon Birrer (Stanford University), Djuna Croon (TRIUMF), Alex Drlica-Wagner (Fermilab, University of Chicago), Jeff A. Dror (UC Berkeley, Lawrence Berkeley National Laboratory), Daniel Grin (Haverford College), David J. E. Marsh (Georg-August University Goettingen), Philip Mocz (Princeton), Ethan Nadler (Stanford), Chanda Prescod-Weinstein (University of New Hamp- shire), Keir K. Rogers (Oskar Klein Centre for Cosmoparticle Physics, Stockholm University; Dunlap Insti- tute, University of Toronto), Katelin Schutz (MIT), Neelima Sehgal (Stony Brook University), Yu-Dai Tsai (Fermilab), Tien-Tien Yu (University of Oregon), Yimin Zhong (University of Chicago). Abstract: Ultra-light axions are a compelling dark matter candidate, motivated by the string axiverse, the strong CP problem in QCD, and possible tensions in the CDM model. They are hard to probe experimentally, and so cosmological/astrophysical observations are very sensitive to the distinctive gravitational phenomena of ULA dark matter. There is the prospect of probing fifteen orders of magnitude in mass, often down to sub-percent contributions to the DM in the next ten to twenty years. -
Mixed Axion/Neutralino Cold Dark Matter in Supersymmetric Models
Preprint typeset in JHEP style - HYPER VERSION Mixed axion/neutralino cold dark matter in supersymmetric models Howard Baera, Andre Lessaa, Shibi Rajagopalana,b and Warintorn Sreethawonga aDept. of Physics and Astronomy, University of Oklahoma, Norman, OK 73019, USA bLaboratoire de Physique Subatomique et de Cosmologie, UJF Grenoble 1, CNRS/IN2P3, INPG, 53 Avenue des Martyrs, F-38026 Grenoble, France E-mail: [email protected], [email protected], [email protected],[email protected] Abstract: We consider supersymmetric (SUSY) models wherein the strong CP problem is solved by the Peccei-Quinn (PQ) mechanism with a concommitant axion/axino supermul- tiplet. We examine R-parity conserving models where the neutralino is the lightest SUSY particle, so that a mixture of neutralinos and axions serve as cold dark matter (aZ1 CDM). The mixed aZ1 CDM scenario can match the measured dark matter abundance for SUSY models which typically give too low a value of the usual thermal neutralino abundance,e such as modelse with wino-like or higgsino-like dark matter. The usual thermal neutralino abundance can be greatly enhanced by the decay of thermally-produced axinos (˜a) to neu- tralinos, followed by neutralino re-annihilation at temperatures much lower than freeze-out. In this case, the relic density is usually neutralino dominated, and goes as (f /N)/m3/2. ∼ a a˜ If axino decay occurs before neutralino freeze-out, then instead the neutralino abundance can be augmented by relic axions to match the measured abundance. Entropy production from late-time axino decays can diminish the axion abundance, but ultimately not the arXiv:1103.5413v1 [hep-ph] 28 Mar 2011 neutralino abundance. -
WNPPC Program Booklet
58th Winter Nuclear & Particle Physics Virtual Conference WNPPC 2021 February 9-12 2021 WNPPC.TRIUMF.CA Book of Abstracts 58th WINTER NUCLEAR AND PARTICLE PHYSICS CONFERENCE WNPPC 2021 Virtual Online Conference February 9 - 12, 2021 Organizing Committee Soud Al Kharusi . McGill Alain Bellerive . Carleton Thomas Brunner . current chair, McGill Jens Dilling . TRIUMF Beatrice Franke . future chair, TRIUMF Dana Giasson . TRIUMF Gwen Grinyer . Regina Blair Jamieson . past chair, Winnipeg Allayne McGowan . TRIUMF Tony Noble . Queen's Ken Ragan . McGill Hussain Rasiwala . McGill Jana Thomson . TRIUMF Andreas Warburton . McGill Hosted by McGill University and TRIUMF WNPPC j i Welcome to WNPPC 2021! On behalf of the organizing committee, I would like to welcome you to the 58th Winter Nuclear and Particle Physics Conference. As always, this year's conference brings to- gether scientists from the entire Canadian subatomic physics community and serves as an important venue for our junior scientists and researchers from across the country to network and socialize. Unlike previous conferences of this series, we will unfortunately not be able to meet in person this year. WNPPC 2021 will be a virtual online conference. A big part of WNPPC, besides all the excellent physics presentations, has been the opportunity to meet old friends and make new ones, and to discuss physics, talk about life, and develop our community. The social aspect of WNPPC has been one of the things that makes this conference so special and dear to many of us. Our goal in the organizing committee has been to keep this spirit alive this year despite being restricted to a virtual format, and provide ample opportunities to meet with peers, form new friendships, and enjoy each other's company. -
Origin and Evolution of the Universe Baryogenesis
Physics 224 Spring 2008 Origin and Evolution of the Universe Baryogenesis Lecture 18 - Monday Mar 17 Joel Primack University of California, Santa Cruz Post-Inflation Baryogenesis: generation of excess of baryon (and lepton) number compared to anti-baryon (and anti-lepton) number. in order to create the observed baryon number today it is only necessary to create an excess of about 1 quark and lepton for every ~109 quarks+antiquarks and leptons +antileptons. Other things that might happen Post-Inflation: Breaking of Pecci-Quinn symmetry so that the observable universe is composed of many PQ domains. Formation of cosmic topological defects if their amplitude is small enough not to violate cosmological bounds. There is good evidence that there are no large regions of antimatter (Cohen, De Rujula, and Glashow, 1998). It was Andrei Sakharov (1967) who first suggested that the baryon density might not represent some sort of initial condition, but might be understandable in terms of microphysical laws. He listed three ingredients to such an understanding: 1. Baryon number violation must occur in the fundamental laws. At very early times, if baryon number violating interactions were in equilibrium, then the universe can be said to have “started” with zero baryon number. Starting with zero baryon number, baryon number violating interactions are obviously necessary if the universe is to end up with a non-zero asymmetry. As we will see, apart from the philosophical appeal of these ideas, the success of inflationary theory suggests that, shortly after the big bang, the baryon number was essentially zero. 2. CP-violation: If CP (the product of charge conjugation and parity) is conserved, every reaction which produces a particle will be accompanied by a reaction which produces its antiparticle at precisely the same rate, so no baryon number can be generated. -
Axionyx: Simulating Mixed Fuzzy and Cold Dark Matter
AxioNyx: Simulating Mixed Fuzzy and Cold Dark Matter Bodo Schwabe,1, ∗ Mateja Gosenca,2, y Christoph Behrens,1, z Jens C. Niemeyer,1, 2, x and Richard Easther2, { 1Institut f¨urAstrophysik, Universit¨atG¨ottingen,Germany 2Department of Physics, University of Auckland, New Zealand (Dated: July 17, 2020) The distinctive effects of fuzzy dark matter are most visible at non-linear galactic scales. We present the first simulations of mixed fuzzy and cold dark matter, obtained with an extended version of the Nyx code. Fuzzy (or ultralight, or axion-like) dark matter dynamics are governed by the comoving Schr¨odinger-Poisson equation. This is evolved with a pseudospectral algorithm on the root grid, and with finite differencing at up to six levels of adaptive refinement. Cold dark matter is evolved with the existing N-body implementation in Nyx. We present the first investigations of spherical collapse in mixed dark matter models, focusing on radial density profiles, velocity spectra and soliton formation in collapsed halos. We find that the effective granule masses decrease in proportion to the fraction of fuzzy dark matter which quadratically suppresses soliton growth, and that a central soliton only forms if the fuzzy dark matter fraction is greater than 10%. The Nyx framework supports baryonic physics and key astrophysical processes such as star formation. Consequently, AxioNyx will enable increasingly realistic studies of fuzzy dark matter astrophysics. I. INTRODUCTION Small-scale differences open the possibility of observa- tional comparisons of FDM and CDM. Moreover, the ob- The physical nature of dark matter is a major open served small scale properties of galaxies may be in tension question for both astrophysics and particle physics. -
The Ups and Downs of Baryon Oscillations
The Ups and Downs of Baryon Oscillations Eric V. Linder Physics Division, Lawrence Berkeley Laboratory, Berkeley, CA 94720 ABSTRACT Baryon acoustic oscillations, measured through the patterned distribution of galaxies or other baryon tracing objects on very large (∼> 100 Mpc) scales, offer a possible geometric probe of cosmological distances. Pluses and minuses in this approach’s leverage for understanding dark energy are discussed, as are systematic uncertainties requiring further investigation. Conclusions are that 1) BAO offer promise of a new avenue to distance measurements and further study is warranted, 2) the measurements will need to attain ∼ 1% accuracy (requiring a 10000 square degree spectroscopic survey) for their dark energy leverage to match that from supernovae, but do give complementary information at 2% accuracy. Because of the ties to the matter dominated era, BAO is not a replacement probe of dark energy, but a valuable complement. 1. Introduction This paper provides a pedagogical introduction to baryon acoustic oscillations (BAO), accessible to readers not necessarily familiar with details of large scale structure in the universe. In addition, it summarizes some of the current issues – plus and minus – with the use of BAO as a cosmological probe of the nature of dark energy. For more quantitative, arXiv:astro-ph/0507308v2 17 Jan 2006 technical discussions of these issues, see White (2005). The same year as the detection of the cosmic microwave background, the photon bath remnant from the hot, early universe, Sakharov (1965) predicted the presence of acoustic oscillations in a coupled baryonic matter distribution. In his case, baryons were coupled to cold electrons rather than hot photons; Peebles & Yu (1970) and Sunyaev & Zel’dovich (1970) pioneered the correct, hot case. -
Inflation in a General Reionization Scenario
Cosmology on the beach, Puerto Vallarta , Mexico 13/01/2011 InflationInflation inin aa generalgeneral reionizationreionization scenarioscenario Stefania Pandolfi, University of Rome “La Sapienza” “Harrison-Zel’dovich primordial spectrum is consistent with observations” S.Pandolfi, A. Cooray, E. Giusarma, E. W. Kolb, A. Melchiorri, O. Mena, P.Serra Phys.Rev.D82:123527,2010 , arXiv:1003.4763v1[astro-ph.CO] “Impact of general reionization scenario on reconstruction of inflationary parameters” S. Pandolfi, E.Giusarma, E.W.Kolb, M. Lattanzi, A.Melchiorri, O.Mena, M.Pena, P.Serra, A.Cooray, Phys.Rev.D82:087302,2010 ,arXiv:1009.5433 [astro-ph.CO] Outline Inflation Harrison-Zel’dovich model CMB Observables and present status Parametrizations of Reionization History Sudden Reionization Mortonson & Hu PC’s Analysis and Results I and II Forecast future constraints: the Planck mission Conclusions InflationInflation 11 • Period of accelerating expansion in the very early Universe • It explains why the Universe is approximately homogeneous and spatially flat • Dominant paradigm for explaining the initial conditions for structure formation and CMB anisotropies • Two types of metric perturbation created during inflation : scalar and tensor (or GW perturbation ) TheThe simplestsimplest way:way: thethe InflatonInflaton φφφφφφ 1 φ + φ + φ = ρ = V (φ) + φ&2 && 3H & V (' ) 0 2 1 p = −V (φ) + φ&2 2 InflationInflation 22 The slope of the inflaton ’’s potential must be sufficiently shallow to drive exponential expansion The amplitude of the potential must be sufficiently large to dominate the energy density of the Universe Slow -roll condition Having inflation requires that the “slow -roll ” parameters ε << 1 ; η << 1 Zoology of models Within these condition the number of models available to choose from is large depending of the relation between the two slow -roll parameters . -
The Cosmological Higgstory of the Vacuum Instability
SLAC-PUB-16698 CERN-PH-TH-2015/119 IFUP-TH/2015 The cosmological Higgstory of the vacuum instability Jos´eR. Espinosaa;b, Gian F. Giudicec, Enrico Morganted, Antonio Riottod, Leonardo Senatoree, Alessandro Strumiaf;g, Nikolaos Tetradish a IFAE, Universitat Aut´onomade Barcelona, 08193 Bellaterra, Barcelona b ICREA, Instituci´oCatalana de Recerca i Estudis Avan¸cats,Barcelona, Spain c CERN, Theory Division, Geneva, Switzerland d D´epartement de Physique Th´eoriqueand Centre for Astroparticle Physics (CAP), Universit´ede Gen`eve,Geneva, Switzerland e Stanford Institute for Theoretical Physics and Kavli Institute for Particle Astrophysics and Cosmology, Physics Department and SLAC, Stanford, CA 94025, USA f Dipartimento di Fisica dell’Universit`adi Pisa and INFN, Italy g National Institute of Chemical Physics and Biophysics, Tallinn, Estonia h Department of Physics, University of Athens, Zographou 157 84, Greece Abstract The Standard Model Higgs potential becomes unstable at large field values. After clarifying the issue of gauge dependence of the effective potential, we study the cosmological evolution of the Higgs field in presence of this instability throughout inflation, reheating and the present epoch. We conclude that anti-de Sitter patches in which the Higgs field lies at its true vacuum are lethal for our universe. From this result, we derive upper bounds on the arXiv:1505.04825v2 [hep-ph] 4 Sep 2015 Hubble constant during inflation, which depend on the reheating temperature and on the Higgs coupling to the scalar curvature or to the inflaton. Finally we study how a speculative link between Higgs meta-stability and consistence of quantum gravity leads to a sharp prediction for the Higgs and top masses, which is consistent with measured values. -
Cosmic Microwave Background
1 29. Cosmic Microwave Background 29. Cosmic Microwave Background Revised August 2019 by D. Scott (U. of British Columbia) and G.F. Smoot (HKUST; Paris U.; UC Berkeley; LBNL). 29.1 Introduction The energy content in electromagnetic radiation from beyond our Galaxy is dominated by the cosmic microwave background (CMB), discovered in 1965 [1]. The spectrum of the CMB is well described by a blackbody function with T = 2.7255 K. This spectral form is a main supporting pillar of the hot Big Bang model for the Universe. The lack of any observed deviations from a 7 blackbody spectrum constrains physical processes over cosmic history at redshifts z ∼< 10 (see earlier versions of this review). Currently the key CMB observable is the angular variation in temperature (or intensity) corre- lations, and to a growing extent polarization [2–4]. Since the first detection of these anisotropies by the Cosmic Background Explorer (COBE) satellite [5], there has been intense activity to map the sky at increasing levels of sensitivity and angular resolution by ground-based and balloon-borne measurements. These were joined in 2003 by the first results from NASA’s Wilkinson Microwave Anisotropy Probe (WMAP)[6], which were improved upon by analyses of data added every 2 years, culminating in the 9-year results [7]. In 2013 we had the first results [8] from the third generation CMB satellite, ESA’s Planck mission [9,10], which were enhanced by results from the 2015 Planck data release [11, 12], and then the final 2018 Planck data release [13, 14]. Additionally, CMB an- isotropies have been extended to smaller angular scales by ground-based experiments, particularly the Atacama Cosmology Telescope (ACT) [15] and the South Pole Telescope (SPT) [16]. -
Axion Dark Matter from Higgs Inflation with an Intermediate H∗
Axion dark matter from Higgs inflation with an intermediate H∗ Tommi Tenkanena and Luca Visinellib;c;d aDepartment of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA bDepartment of Physics and Astronomy, Uppsala University, L¨agerhyddsv¨agen1, 75120 Uppsala, Sweden cNordita, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, 10691 Stockholm, Sweden dGravitation Astroparticle Physics Amsterdam (GRAPPA), Institute for Theoretical Physics Amsterdam and Delta Institute for Theoretical Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands E-mail: [email protected], [email protected], [email protected] Abstract. In order to accommodate the QCD axion as the dark matter (DM) in a model in which the Peccei-Quinn (PQ) symmetry is broken before the end of inflation, a relatively low scale of inflation has to be invoked in order to avoid bounds from DM isocurvature 9 fluctuations, H∗ . O(10 ) GeV. We construct a simple model in which the Standard Model Higgs field is non-minimally coupled to Palatini gravity and acts as the inflaton, leading to a 8 scale of inflation H∗ ∼ 10 GeV. When the energy scale at which the PQ symmetry breaks is much larger than the scale of inflation, we find that in this scenario the required axion mass for which the axion constitutes all DM is m0 . 0:05 µeV for a quartic Higgs self-coupling 14 λφ = 0:1, which correspond to the PQ breaking scale vσ & 10 GeV and tensor-to-scalar ratio r ∼ 10−12. Future experiments sensitive to the relevant QCD axion mass scale can therefore shed light on the physics of the Universe before the end of inflation. -
Banks-Zaks Cosmology, Inflation, and the Big Bang Singularity
Prepared for submission to JCAP Banks-Zaks Cosmology, Inflation, and the Big Bang Singularity Michal Artymowski, Ido Ben-Dayan, Utkarsh Kumar Physics Department, Ariel University, Ariel 40700, Israel E-mail: [email protected], [email protected], [email protected] Abstract. We consider the thermodynamical behavior of Banks-Zaks theory close to the conformal point in a cosmological setting. Due to the anomalous dimension, the resulting pressure and energy density deviate from that of radiation and result in various interesting cosmological scenarios. Specifically, for a given range of parameters one avoids the cosmological singularity. We provide a full "phase diagram" of possible Universe evolution for the given parameters. For a certain range of parameters, the thermal averaged Banks-Zaks theory alone results in an exponentially contracting uni- verse followed by a non-singular bounce and an exponentially expanding universe, i.e. Inflation without a Big Bang singularity, or shortly termed "dS Bounce". The tem- perature of such a universe is bounded from above and below. The result is a theory violating the classical Null Energy Condition (NEC). Considering the Banks-Zaks the- ory with an additional perfect fluid, yields an even richer phase diagram that includes the standard Big Bang model, stable single "normal" bounce, dS Bounce and stable cyclic solutions. The bouncing and cyclic solutions are with no singularities, and the violation of the NEC happens only near the bounce. We also provide simple analytical conditions for the existence of these non-singular solutions. Hence, within effective field theory, we have a new alternative non-singular cosmology based on the anoma- arXiv:1912.10532v2 [hep-th] 13 May 2020 lous dimension of Bank-Zaks theory that may include inflation and without resorting to scalar fields.