What Happened Before the Big Bang?
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Washington, Wednesday, January 25, 1950
VOLUME 15 ■ NUMBER 16 Washington, Wednesday, January 25, 1950 TITLE 3— THE PRESIDENT in paragraph (a) last above, to the in CONTENTS vention is insufficient equitably to justify EXECUTIVE ORDER 10096 a requirement of assignment to the Gov THE PRESIDENT ernment of the entire right, title and P roviding for a U niform P atent P olicy Executive Order Pase for the G overnment W ith R espect to interest to such invention, or in any case where the Government has insufficient Inventions made by Government I nventions M ade by G overnment interest in an invention to obtain entire employees; providing, for uni E mployees and for the Administra form patent policy for Govern tion of Such P olicy right, title and interest therein (although the Government could obtain some under ment and for administration of WHEREAS inventive advances in paragraph (a), above), the Government such policy________________ 389 scientific and technological fields fre agency concerned, subject to the ap quently result from governmental ac proval of the Chairman of the Govern EXECUTIVE AGENCIES tivities carried on by Government ment Patents Board (provided for in Agriculture Department employees; and paragraph 3 of this order and herein See Commodity Credit Corpora WHEREAS the Government of the after referred to as the Chairman), shall tion ; Forest Service; Production United States is expending large sums leave title to such invention in the and Marketing Administration. of money annually for the conduct of employee, subject, however, to the reser these activities; -
String Theory and Pre-Big Bang Cosmology
IL NUOVO CIMENTO 38 C (2015) 160 DOI 10.1393/ncc/i2015-15160-8 Colloquia: VILASIFEST String theory and pre-big bang cosmology M. Gasperini(1)andG. Veneziano(2) (1) Dipartimento di Fisica, Universit`a di Bari - Via G. Amendola 173, 70126 Bari, Italy and INFN, Sezione di Bari - Bari, Italy (2) CERN, Theory Unit, Physics Department - CH-1211 Geneva 23, Switzerland and Coll`ege de France - 11 Place M. Berthelot, 75005 Paris, France received 11 January 2016 Summary. — In string theory, the traditional picture of a Universe that emerges from the inflation of a very small and highly curved space-time patch is a possibility, not a necessity: quite different initial conditions are possible, and not necessarily unlikely. In particular, the duality symmetries of string theory suggest scenarios in which the Universe starts inflating from an initial state characterized by very small curvature and interactions. Such a state, being gravitationally unstable, will evolve towards higher curvature and coupling, until string-size effects and loop corrections make the Universe “bounce” into a standard, decreasing-curvature regime. In such a context, the hot big bang of conventional cosmology is replaced by a “hot big bounce” in which the bouncing and heating mechanisms originate from the quan- tum production of particles in the high-curvature, large-coupling pre-bounce phase. Here we briefly summarize the main features of this inflationary scenario, proposed a quarter century ago. In its simplest version (where it represents an alternative and not a complement to standard slow-roll inflation) it can produce a viable spectrum of density perturbations, together with a tensor component characterized by a “blue” spectral index with a peak in the GHz frequency range. -
Big Bang Blunder Bursts the Multiverse Bubble
WORLD VIEW A personal take on events IER P P. PA P. Big Bang blunder bursts the multiverse bubble Premature hype over gravitational waves highlights gaping holes in models for the origins and evolution of the Universe, argues Paul Steinhardt. hen a team of cosmologists announced at a press world will be paying close attention. This time, acceptance will require conference in March that they had detected gravitational measurements over a range of frequencies to discriminate from fore- waves generated in the first instants after the Big Bang, the ground effects, as well as tests to rule out other sources of confusion. And Worigins of the Universe were once again major news. The reported this time, the announcements should be made after submission to jour- discovery created a worldwide sensation in the scientific community, nals and vetting by expert referees. If there must be a press conference, the media and the public at large (see Nature 507, 281–283; 2014). hopefully the scientific community and the media will demand that it According to the team at the BICEP2 South Pole telescope, the is accompanied by a complete set of documents, including details of the detection is at the 5–7 sigma level, so there is less than one chance systematic analysis and sufficient data to enable objective verification. in two million of it being a random occurrence. The results were The BICEP2 incident has also revealed a truth about inflationary the- hailed as proof of the Big Bang inflationary theory and its progeny, ory. The common view is that it is a highly predictive theory. -
Philip Gibbs EVENT-SYMMETRIC SPACE-TIME
Event-Symmetric Space-Time “The universe is made of stories, not of atoms.” Muriel Rukeyser Philip Gibbs EVENT-SYMMETRIC SPACE-TIME WEBURBIA PUBLICATION Cyberspace First published in 1998 by Weburbia Press 27 Stanley Mead Bradley Stoke Bristol BS32 0EF [email protected] http://www.weburbia.com/press/ This address is supplied for legal reasons only. Please do not send book proposals as Weburbia does not have facilities for large scale publication. © 1998 Philip Gibbs [email protected] A catalogue record for this book is available from the British Library. Distributed by Weburbia Tel 01454 617659 Electronic copies of this book are available on the world wide web at http://www.weburbia.com/press/esst.htm Philip Gibbs’s right to be identified as the author of this work has been asserted by him in accordance with the Copyright, Designs and Patents Act 1988. All rights reserved, except that permission is given that this booklet may be reproduced by photocopy or electronic duplication by individuals for personal use only, or by libraries and educational establishments for non-profit purposes only. Mass distribution of copies in any form is prohibited except with the written permission of the author. Printed copies are printed and bound in Great Britain by Weburbia. Dedicated to Alice Contents THE STORYTELLER ................................................................................... 11 Between a story and the world ............................................................. 11 Dreams of Rationalism ....................................................................... -
DARK AGES of the Universe the DARK AGES of the Universe Astronomers Are Trying to fill in the Blank Pages in Our Photo Album of the Infant Universe by Abraham Loeb
THE DARK AGES of the Universe THE DARK AGES of the Universe Astronomers are trying to fill in the blank pages in our photo album of the infant universe By Abraham Loeb W hen I look up into the sky at night, I often wonder whether we humans are too preoccupied with ourselves. There is much more to the universe than meets the eye on earth. As an astrophysicist I have the privilege of being paid to think about it, and it puts things in perspective for me. There are things that I would otherwise be bothered by—my own death, for example. Everyone will die sometime, but when I see the universe as a whole, it gives me a sense of longevity. I do not care so much about myself as I would otherwise, because of the big picture. Cosmologists are addressing some of the fundamental questions that people attempted to resolve over the centuries through philosophical thinking, but we are doing so based on systematic observation and a quantitative methodology. Perhaps the greatest triumph of the past century has been a model of the uni- verse that is supported by a large body of data. The value of such a model to our society is sometimes underappreciated. When I open the daily newspaper as part of my morning routine, I often see lengthy de- scriptions of conflicts between people about borders, possessions or liberties. Today’s news is often forgotten a few days later. But when one opens ancient texts that have appealed to a broad audience over a longer period of time, such as the Bible, what does one often find in the opening chap- ter? A discussion of how the constituents of the universe—light, stars, life—were created. -
United States District Court Southern District Of
Case 3:11-cv-01812-JM-JMA Document 31 Filed 02/20/13 Page 1 of 10 1 2 3 4 5 6 7 8 9 UNITED STATES DISTRICT COURT 10 SOUTHERN DISTRICT OF CALIFORNIA 11 12 In re JIFFY LUBE ) Case No.: 3:11-MD-2261-JM (JMA) INTERNATIONAL, INC. TEXT ) 13 SPAM LITIGATION ) FINAL APPROVAL OF CLASS ) ACTION AND ORDER OF 14 ) DISMISSAL WITH PREJUDICE ) 15 16 Pending before the Court are Plaintiffs’ Motion for Final Approval of Class 17 Action Settlement (Dkt. 90) and Plaintiffs’ Motion for Approval of Attorneys’ Fees and 18 Expenses and Class Representative Incentive Awards (Dkt. 86) (collectively, the 19 “Motions”). The Court, having reviewed the papers filed in support of the Motions, 20 having heard argument of counsel, and finding good cause appearing therein, hereby 21 GRANTS Plaintiffs’ Motions and it is hereby ORDERED, ADJUDGED, and DECREED 22 THAT: 23 1. Terms and phrases in this Order shall have the same meaning as ascribed to 24 them in the Parties’ August 1, 2012 Class Action Settlement Agreement, as amended by 25 the First Amendment to Class Action Settlement Agreement as of September 28, 2012 26 (the “Settlement Agreement”). 27 2. This Court has jurisdiction over the subject matter of this action and over all 28 Parties to the Action, including all Settlement Class Members. 1 3:11-md-2261-JM (JMA) Case 3:11-cv-01812-JM-JMA Document 31 Filed 02/20/13 Page 2 of 10 1 3. On October 10, 2012, this Court granted Preliminary Approval of the 2 Settlement Agreement and preliminarily certified a settlement class consisting of: 3 4 All persons or entities in the United States and its Territories who in April 2011 were sent a text message from short codes 5 72345 or 41411 promoting Jiffy Lube containing language similar to the following: 6 7 JIFFY LUBE CUSTOMERS 1 TIME OFFER: REPLY Y TO JOIN OUR ECLUB FOR 45% OFF 8 A SIGNATURE SERVICE OIL CHANGE! STOP TO 9 UNSUB MSG&DATA RATES MAY APPLY T&C: JIFFYTOS.COM. -
David Kirkby University of California, Irvine, USA 4 August 2020 Expanding Universe
COSMOLOGY IN THE 2020S David Kirkby University of California, Irvine, USA 4 August 2020 Expanding Universe... 2 expansion history a(t |Ωm, ΩDE, …) 3 4 redshift 5 6 0.38Myr opaque universe last scatter 7 inflation opaque universe last scatter gravity waves? 8 CHIME SPT-3G DES 9 TCMB=2.7K, λ~2mm 10 CMB TCMB=2.7K, λ~2mm Galaxies 11 microwave projects: cosmic microwave background (primordial gravity waves, neutrinos, ...) CMB Galaxies optical & NIR projects: galaxy surveys (dark energy, neutrinos, ...) 12 CMB Galaxies telescope location: ground / above atmosphere 13 CMB Atacama desert, Chile CMB ground telescope location: Atacama desert / South Pole 14 Galaxies Galaxy survey instrument: spectrograph / imager 15 Dark Energy Spectroscopic Instrument (DESI) Vera Rubin Observatory 16 Dark Energy Spectroscopic Instrument (DESI) Vera Rubin Observatory 17 EXPANSION HISTORY VS STRUCTURE GROWTH Measurements of our cosmic expansion history constrain the parameters of an expanding homogenous universe: SN LSS , …) expansion historyDE m, Ω a(t |Ω CMB Small inhomogeneities are growing against this backdrop. Measurements of this structure growth provide complementary constraints. 18 Structure Growth 19 Redshift is not a perfect proxy for distance because of galaxy peculiar motions. Large-scale redshift-space distortions (RSD) trace large-scale matter fluctuations: signal! 20 Angles measured on the sky are also distorted by weak lensing (WL) as light is deflected by the same large-scale matter fluctuations: signal! Large-scale redshift-space distortions (RSD) trace large-scale matter fluctuations: signal! 21 CMB measures initial conditions of structure growth at z~1090: Temperature CMB photons also experience weak lensing! https://wiki.cosmos.esa.int/planck-legacy-archive/index.php/CMB_maps Polarization 22 CMB: INFLATION ERA SIGNATURES https://www.annualreviews.org/doi/abs/10.1146/annurev-astro-081915-023433 lensing E-modes lensing B-modes GW B-modes https://arxiv.org/abs/1907.04473 Lensing B modes already observed. -
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. -
A New Universe to Discover: a Guide to Careers in Astronomy
A New Universe to Discover A Guide to Careers in Astronomy Published by The American Astronomical Society What are Astronomy and Astrophysics? Ever since Galileo first turned his new-fangled one-inch “spyglass” on the moon in 1609, the popular image of the astronomer has been someone who peers through a telescope at the night sky. But astronomers virtually never put eye to lens these days. The main source of astronomical data is still photons (particles of light) from space, but the tools used to gather and analyze them are now so sophisticated that it’s no longer necessary (or even possible, in most cases) for a human eye to look through them. But for all the high-tech gadgetry, the 21st-Century astronomer is still trying to answer the same fundamental questions that puzzled Galileo: How does the universe work, and where did it come from? Webster’s dictionary defines “astronomy” as “the science that deals with the material universe beyond the earth’s atmosphere.” This definition is broad enough to include great theoretical physicists like Isaac Newton, Albert Einstein, and Stephen Hawking as well as astronomers like Copernicus, Johanes Kepler, Fred Hoyle, Edwin Hubble, Carl Sagan, Vera Rubin, and Margaret Burbidge. In fact, the words “astronomy” and “astrophysics” are pretty much interchangeable these days. Whatever you call them, astronomers seek the answers to many fascinating and fundamental questions. Among them: *Is there life beyond earth? *How did the sun and the planets form? *How old are the stars? *What exactly are dark matter and dark energy? *How did the Universe begin, and how will it end? Astronomy is a physical (non-biological) science, like physics and chemistry. -
The Big Bang Cosmological Model: Theory and Observations
THE BIG BANG COSMOLOGICAL MODEL: THEORY AND OBSERVATIONS MARTINA GERBINO INFN, sezione di Ferrara ISAPP 2021 Valencia July 22st, 2021 1 Structure formation Maps of CMB anisotropies show the Universe as it was at the time of recombination. The CMB field is isotropic and !" the rms fluctuations (in total intensity) are very small, < | |# > ~10$% (even smaller in polarization). Density " perturbations � ≡ ��/� are proportional to CMB fluctuations. It is possible to show that, at recombination, perturbations could be from a few (for baryons) to at most 100 times (for CDM) larger than CMB fluctuations. We need a theory of structure formation that allows to link the tiny perturbations at z~1100 to the large scale structure of the Universe we observe today (from galaxies to clusters and beyond). General picture: small density perturbations grow via gravitational instability (Jeans mechanism). The growth is suppressed during radiation-domination and eventually kicks-off after the time of equality (z~3000). When inside the horizon, perturbations grow proportional to the scale factor as long as they are in MD and remain in the linear regime (� ≪ 1). M. GERBINO 2 ISAPP-VALENCIA, 22 JULY 2021 Preliminaries & (⃗ $&) Density contrast �(�⃗) ≡ and its Fourier expansion � = ∫ �+� �(�⃗) exp(��. �⃗) &) * Credits: Kolb&Turner 2� � � ≡ ; � = ; � = ��; � ,-./ � ,-./ � � �+, �� � ≡ �+ �; � � = �(�)$+� ∝ 6 ,-./ -01 6 �+/#, �� �+ �(�) ≈ �3 -01 2� The amplitude of perturbations as they re-enter the horizon is given by the primordial power spectrum. Once perturbations re-enter the horizon, micro-physics processes modify the primordial spectrum Scale factor M. GERBINO 3 ISAPP-VALENCIA, 22 JULY 2021 Jeans mechanism (non-expanding) The Newtonian motion of a perfect fluid is decribed via the Eulerian equations. -
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]. -
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.