Outline of Lecture 2 Baryon Asymmetry of the Universe. What's
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5.1 5. the BARYON ASYMMETRY of the UNIVERSE The
5.1 5. THE BARYON ASYMMETRYOF THE UNIVERSE The new interactions predicted by most grand unified theories are so weak that they are unobservable in the laboratory, except?possibly in proton decay. Fortunately, there was one time at which the new interac- tions would have been very important: the first instant after the big bang when the universe was incredibly hot and dense. This cosmological "laboratory" may have left relics of the grand unified interactions that are observable today. In particular, the new interactions may be responsible for the observed excess of baryons over antibaryons in the universe (the baryon asymmetry). In this chapter I will outline the status of the baryon asymmetry. For a more detailed discussion, especially of the astrophysical aspects, see the recent detailed studies [5.1-5.21 and reviews c5.3-5.61 of earlier work. Another possible relic of the big bang, superheavy magnetic monopoles, is discussed in Chapter 6. Speculations on other possible connections between grand unifica- tion and cosmology, such as galaxy formation [5.7-5.91 or the role of dissipative phencmena in smoothing the universe [5.9-5.101 are discussed in [5.4-5.5,5.71. The Baryon Excess The two facts that one would like to explain are: (a) our region of the universe contains baryons but essentially no anti- baryons. (The observations are reviewed by Steigman r5.111 and Barrow [5.333, and (b) the observed baryon number density to entropy density ratio is 15.1, 5.121 knB 2 lo-9.'8+1.6- S (5.1) 5.2 (This is " l/7 the present baryon to photon density ratio n.B /n y_[5.11. -
Estimation of Baryon Asymmetry of the Universe from Neutrino Physics
ESTIMATION OF BARYON ASYMMETRY OF THE UNIVERSE FROM NEUTRINO PHYSICS Manorama Bora Department of Physics Gauhati University This thesis is submitted to Gauhati University as requirement for the degree of Doctor of Philosophy Faculty of Science March 2018 I would like to dedicate this thesis to my parents . Abstract The discovery of neutrino masses and mixing in neutrino oscillation experiments in 1998 has greatly increased the interest in a mechanism of baryogenesis through leptogenesis, a model of baryogenesis which is a cosmological consequence. The most popular way to explain why neutrinos are massive but at the same time much lighter than all other fermions, is the see-saw mechanism. Thus, leptogenesis realises a highly non-trivial link between two completely independent experimental observations: the absence of antimatter in the observable universe and the observation of neutrino mixings and masses. Therefore, leptogenesis has a built-in double sided nature.. The discovery of Higgs boson of mass 125GeV having properties consistent with the SM, further supports the leptogenesis mechanism. In this thesis we present a brief sketch on the phenomenological status of Standard Model (SM) and its extension to GUT with or without SUSY. Then we review on neutrino oscillation and its implication with latest experiments. We discuss baryogenesis via leptogenesis through the decay of heavy Majorana neutrinos. We also discuss formulation of thermal leptogenesis. At last we try to explore the possibilities for the discrimination of the six kinds of Quasi- degenerate neutrino(QDN)mass models in the light of baryogenesis via leptogenesis. We have seen that all the six QDN mass models are relevant in the context of flavoured leptogenesis. -
Lecture 17 : the Cosmic Microwave Background
Let’s think about the early Universe… Lecture 17 : The Cosmic ! From Hubble’s observations, we know the Universe is Microwave Background expanding ! This can be understood theoretically in terms of solutions of GR equations !Discovery of the Cosmic Microwave ! Earlier in time, all the matter must have been Background (ch 14) squeezed more tightly together ! If crushed together at high enough density, the galaxies, stars, etc could not exist as we see them now -- everything must have been different! !The Hot Big Bang This week: read Chapter 12/14 in textbook 4/15/14 1 4/15/14 3 Let’s think about the early Universe… Let’s think about the early Universe… ! From Hubble’s observations, we know the Universe is ! From Hubble’s observations, we know the Universe is expanding expanding ! This can be understood theoretically in terms of solutions of ! This can be understood theoretically in terms of solutions of GR equations GR equations ! Earlier in time, all the matter must have been squeezed more tightly together ! If crushed together at high enough density, the galaxies, stars, etc could not exist as we see them now -- everything must have been different! ! What was the Universe like long, long ago? ! What were the original contents? ! What were the early conditions like? ! What physical processes occurred under those conditions? ! How did changes over time result in the contents and structure we see today? 4/15/14 2 4/15/14 4 The Poetic Version ! In a brilliant flash about fourteen billion years ago, time and matter were born in a single instant of creation. -
Baryogenesis and Dark Matter from B Mesons: B-Mesogenesis
Baryogenesis and Dark Matter from B Mesons: B-Mesogenesis Miguel Escudero Abenza [email protected] arXiv:1810.00880, PRD 99, 035031 (2019) with: Gilly Elor & Ann Nelson Based on: arXiv:2101.XXXXX with: Gonzalo Alonso-Álvarez & Gilly Elor New Trends in Dark Matter 09-12-2020 The Universe Baryonic Matter 5% 26% Dark Matter 69% Dark Energy Planck 2018 1807.06209 Miguel Escudero (TUM) B-Mesogenesis New Trends in DM 09-12-20 !2 Theoretical Understanding? Motivating Question: What fraction of the Energy Density of the Universe comes from Physics Beyond the Standard Model? 99.85%! Miguel Escudero (TUM) B-Mesogenesis New Trends in DM 09-12-20 !3 SM Prediction: Neutrinos 40% 60% Photons Miguel Escudero (TUM) B-Mesogenesis New Trends in DM 09-12-20 !4 The Universe Baryonic Matter 5% 26% Dark Matter 69% Dark Energy Planck 2018 1807.06209 Miguel Escudero (TUM) B-Mesogenesis New Trends in DM 09-12-20 !5 Baryogenesis and Dark Matter from B Mesons: B-Mesogenesis arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly related to B-Meson observables 3) Leads to unique collider signatures 4) Fully testable at current collider experiments Miguel Escudero (TUM) B-Mesogenesis New Trends in DM 09-12-20 !6 Outline 1) B-Mesogenesis 1) C/CP violation 2) Out of equilibrium 3) Baryon number violation? 2) A Minimal Model & Cosmology 3) Implications for Collider Experiments 4) Dark Matter Phenomenology 5) Summary and Outlook Miguel Escudero (TUM) B-Mesogenesis New Trends in DM 09-12-20 !7 Baryogenesis -
The Matter – Antimatter Asymmetry of the Universe and Baryogenesis
The matter – antimatter asymmetry of the universe and baryogenesis Andrew Long Lecture for KICP Cosmology Class Feb 16, 2017 Baryogenesis Reviews in General • Kolb & Wolfram’s Baryon Number Genera.on in the Early Universe (1979) • Rio5o's Theories of Baryogenesis [hep-ph/9807454]} (emphasis on GUT-BG and EW-BG) • Rio5o & Trodden's Recent Progress in Baryogenesis [hep-ph/9901362] (touches on EWBG, GUTBG, and ADBG) • Dine & Kusenko The Origin of the Ma?er-An.ma?er Asymmetry [hep-ph/ 0303065] (emphasis on Affleck-Dine BG) • Cline's Baryogenesis [hep-ph/0609145] (emphasis on EW-BG; cartoons!) Leptogenesis Reviews • Buchmuller, Di Bari, & Plumacher’s Leptogenesis for PeDestrians, [hep-ph/ 0401240] • Buchmulcer, Peccei, & Yanagida's Leptogenesis as the Origin of Ma?er, [hep-ph/ 0502169] Electroweak Baryogenesis Reviews • Cohen, Kaplan, & Nelson's Progress in Electroweak Baryogenesis, [hep-ph/ 9302210] • Trodden's Electroweak Baryogenesis, [hep-ph/9803479] • Petropoulos's Baryogenesis at the Electroweak Phase Transi.on, [hep-ph/ 0304275] • Morrissey & Ramsey-Musolf Electroweak Baryogenesis, [hep-ph/1206.2942] • Konstandin's Quantum Transport anD Electroweak Baryogenesis, [hep-ph/ 1302.6713] Constituents of the Universe formaon of large scale structure (galaxy clusters) stars, planets, dust, people late ame accelerated expansion Image stolen from the Planck website What does “ordinary matter” refer to? Let’s break it down to elementary particles & compare number densities … electron equal, universe is neutral proton x10 billion 3⇣(3) 3 3 n =3 T 168 cm− neutron x7 ⌫ ⇥ 4⇡2 ⌫ ' matter neutrinos photon positron =0 2⇣(3) 3 3 n = T 413 cm− γ ⇡2 CMB ' anti-proton =0 3⇣(3) 3 3 anti-neutron =0 n =3 T 168 cm− ⌫¯ ⇥ 4⇡2 ⌫ ' anti-neutrinos antimatter What is antimatter? First predicted by Dirac (1928). -
Baryogenesis and Dark Matter from B Mesons
Baryogenesis and Dark Matter from B mesons Abstract: In [1] a new mechanism to simultaneously generate the baryon asymmetry of the Universe and the Dark Matter abundance has been proposed. The Standard Model of particle physics succeeds to describe many physical processes and it has been tested to a great accuracy. However, it fails to provide a Dark Matter candidate, a so far undetected component of matter which makes up roughly 25% of the energy budget of the Universe. Furthermore, the question arises why there is a more matter (or baryons) than antimatter in the Universe taking into account that cosmology predicts a Universe with equal parts matter and anti-matter. The mechanism to generate a primordial matter-antimatter asymmetry is called baryogenesis. Any successful mechanism for baryogenesis needs to satisfy the three Sakharov conditions [2]: • violation of charge symmetry and of the combination of charge and parity symmetry • violation of baryon number • departure from thermal equilibrium In this paper [1] a new mechanism for the generation of a baryon asymmetry together with Dark Matter production has been proposed. The mechanism proposed to explain the observed baryon asymetry as well as the pro- duction of dark matter is developed around a fundamental ingredient: a new scalar particle Φ. The Φ particle is massive and would dominate the energy density of the Universe after inflation but prior to the Bing Bang nucleosynthesis. The same particle will directly decay, out of thermal equilibrium, to b=¯b quarks and if the Universe is cool enough ∼ O(10 MeV), the produced b quarks can hadronize and form B-mesons. -
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. -
Kinetics of Spontaneous Baryogenesis
Kinetics of Spontaneous Baryogenesis Elena Arbuzova Dubna University & Novosibirsk State University based on common work with A.D. Dolgov and V.A. Novikov arXiv:1607.01247 The 10th APCTP-BLTP/JINR-RCNP-RIKEN Joint Workshop on Nuclear and Hadronic Physics Aug. 17 - Aug. 21, 2016, RIKEN, Wako, Japan E. Arbuzova () Kinetics of SBG August 18 1 / 30 Outline Introduction Generalities about SBG Evolution of Baryon Asymmetry Kinetic Equation in Time-dependent Background Conclusions E. Arbuzova () Kinetics of SBG August 18 2 / 30 Standard Cosmological Model (SCM) The Standard Model of Cosmology: the Standard Model of particle physics ) matter content General Relativity ) gravitational interaction the inflationary paradigm ) to fix a few problems of the scenario SCM explains a huge amount of observational data: Hubble's law the primordial abundance of light elements the cosmic microwave background E. Arbuzova () Kinetics of SBG August 18 3 / 30 Some Puzzles Matter Inventory of the Universe: Baryonic matter (mainly protons and neutrons): 5%. Dark matter (weakly interactive particles not belonging to the MSM of particle physics): 25%. Dark energy: 70% of the Universe is really a mystery looking like a uniformly distributed substance with an unusual equation of state P ≈ −%. DE is responsible for the contemporary accelerated expansion of the Universe. The mechanism of inflation still remains at the level of paradigm. It does not fit the framework of the Standard Model of particle physics. Matter-antimatter asymmetry around us: the local Universe is clearly -
Lesson 8 : Baryogenesis
Lesson 8 : Baryogenesis Notes from Prof. Susskind video lectures publicly available on YouTube 1 Introduction Baryogenesis means the creation of matter particles. Its study is more specifically concerned with explaining the excess of matter over antimatter in the universe. The conditions which explain the imbalance of particles and antiparticles are called nowadays the Sakharov conditions 1. In the previous chapter, we studied several landmarks in the temperature of the universe. Going backwads in time, we met the decoupling time when the universe become trans- parent. The temperature was about 4000°. Further back at T ≈ 1010 degrees, photons could create electron-positron pairs. Protons had already been created earlier. Even further back at T ≈ 1012 or 1013, photons could create proton-antiproton pairs. More accurately they could create quark-antiquark pairs, because in truth it was too hot for protons to exist as such. But, at that temperature, let’s say by convention that when we talk about a proton we really talk about three quarks. It does not make any difference in the reasonings. 1. Named after Andrei Sakharov (1921 - 1989), Russian nuclear physicist. Sakharov published his work on this in 1967 in Russian and it remained little known until the 1980s. In the meantime, the same conditions were rediscovered in 1980 by Savas Dimopoulos and Leonard Susskind who were trying to answer the question of why the number of photons, which is a measure of the entropy of the universe, exceeds by eight orders of magnitude the number of protons or electrons. Thus for a time the conditions were known in the West as the Dimopoulos-Susskind conditions. -
Introduction to Flavour Physics
Introduction to flavour physics Y. Grossman Cornell University, Ithaca, NY 14853, USA Abstract In this set of lectures we cover the very basics of flavour physics. The lec- tures are aimed to be an entry point to the subject of flavour physics. A lot of problems are provided in the hope of making the manuscript a self-study guide. 1 Welcome statement My plan for these lectures is to introduce you to the very basics of flavour physics. After the lectures I hope you will have enough knowledge and, more importantly, enough curiosity, and you will go on and learn more about the subject. These are lecture notes and are not meant to be a review. In the lectures, I try to talk about the basic ideas, hoping to give a clear picture of the physics. Thus many details are omitted, implicit assumptions are made, and no references are given. Yet details are important: after you go over the current lecture notes once or twice, I hope you will feel the need for more. Then it will be the time to turn to the many reviews [1–10] and books [11, 12] on the subject. I try to include many homework problems for the reader to solve, much more than what I gave in the actual lectures. If you would like to learn the material, I think that the problems provided are the way to start. They force you to fully understand the issues and apply your knowledge to new situations. The problems are given at the end of each section. -
Present Understanding of Solution to Baryonic Asymmetry of the Universe
Present understanding of solution to baryonic asymmetry of the Universe Present understanding of solution to baryonic asymmetry of the Universe Arnab Dasgupta Centre for Theoretical Physics Jamia Millia Islamia January 6, 2015 Present understanding of solution to baryonic asymmetry of the Universe Motivation for Baryogenesis Types of Baryogenesis Grand Unified Theory (GUT) baryogenesis Leptogenesis Electroweak Barogenesis Affleck-Dine Mechanism Leptogenesis Soft Leptogenesis Conclusion 1. If baryon asymmetry had been an initial condition, it would have been a highly fined tuned one. For every 6000000 anti-quarks there should be 6000001 quarks. 2. And more importantly, we have a good reason to believe from the CMB that there was an era of inflation during early history of the Universe. So, any primodial asymmetry would have been exponentially diluted away by the required amount of inflation. I There are atleast two reasons for believing that the baryons asymmetry has been dynamically generated. Present understanding of solution to baryonic asymmetry of the Universe Motivation for Baryogenesis I Observations indicate that the number of baryons (protons and neutrons) in the Universe in unequal to the numbers of anti-baryons (anti protons and anti- neutrons). 1. If baryon asymmetry had been an initial condition, it would have been a highly fined tuned one. For every 6000000 anti-quarks there should be 6000001 quarks. 2. And more importantly, we have a good reason to believe from the CMB that there was an era of inflation during early history of the Universe. So, any primodial asymmetry would have been exponentially diluted away by the required amount of inflation. -
Baryogenesis and Dark Matter from B Mesons
Baryogenesis and Dark Matter from B Mesons Miguel Escudero Abenza [email protected] Based on arXiv:1810.00880 Phys. Rev. D 99, 035031 (2019) with: Gilly Elor & Ann Nelson BLV19 24-10-2019 DARKHORIZONS The Universe Baryonic Matter 5 % 26 % Dark Matter 69 % Dark Energy Planck 2018 1807.06209 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 2 SM Prediction: Neutrinos 40 % 60 % Photons Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 3 The Universe Baryonic Matter 5 % 26 % Dark Matter 69 % Dark Energy Planck 2018 1807.06209 Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 4 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly related to B-Meson observables Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly related to B-Meson observables 3) Leads to unique collider signatures Miguel Escudero (KCL) Baryogenesis and DM from B Mesons BLV19 24-10-19 5 Baryogenesis and Dark Matter from B Mesons arXiv:1810.00880 Elor, Escudero & Nelson 1) Baryogenesis and Dark Matter are linked 2) Baryon asymmetry directly