(Vacuum) Energy and Quantum Field
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Varying Constants, Gravitation and Cosmology
Varying constants, Gravitation and Cosmology Jean-Philippe Uzan Institut d’Astrophysique de Paris, UMR-7095 du CNRS, Universit´ePierre et Marie Curie, 98 bis bd Arago, 75014 Paris (France) and Department of Mathematics and Applied Mathematics, Cape Town University, Rondebosch 7701 (South Africa) and National Institute for Theoretical Physics (NITheP), Stellenbosch 7600 (South Africa). email: [email protected] http//www2.iap.fr/users/uzan/ September 29, 2010 Abstract Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to mat- ter. This will induce a violation of the universality of free fall. It is thus of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We thus detail the relations between the constants, the tests of the local posi- tion invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, Solar system observations, meteorites dating, quasar absorption spectra, stellar physics, pul- sar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we arXiv:1009.5514v1 [astro-ph.CO] 28 Sep 2010 describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of differ- ent constants. -
Vacuum As a Physical Medium
cu - TP - 626 / EERNIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII I.12RI=IR1I;s. QI.; 621426 VACUUM AS A PHYSICAL MEDIUM (RELATIVISTIC HEAVY ION COLLISIONS AND THE BOLTZMANN EQUAT ION) T. D. LEE COLUMBIA UNIvERsI1Y, New Y0RI<, N.Y. 10027 A LECTURE GIVEN AT THE INTERNATIONAL SYMPOSIUM IN HONOUR OF BOLTZMANN'S 1 50TH BIRTHDAY, FEBRUARY 1994. THIS RESEARCH WAS SUPPORTED IN PART BY THE U.S. DEPARTMENT OF ENERGY. OCR Output OCR OutputVACUUM AS A PHYSICAL MEDIUM (Relativistic Heavy Ion Collisions and the Boltzmann Equation) T. D. Lee Columbia University, New York, N.Y. 10027 It is indeed a privilege for me to attend this international symposium in honor of Boltzmann's 150th birthday. ln this lecture, I would like to cover the following topics: 1) Symmetries and Asymmetries: Parity P (right—left symmetry) Charge conjugation C (particle-antiparticle symmetry) Time reversal T Their violations and CPT symmetry. 2) Two Puzzles of Modern Physics: Missing symmetry Vacuum as a physical medium Unseen quarks. 3) Relativistic Heavy Ion Collisions (RHIC): How to excite the vacuum? Phase transition of the vacuum Hanbury-Brown-Twiss experiments. 4) Application of the Relativistic Boltzmann Equations: ARC model and its Lorentz invariance AGS experiments and physics in ultra-heavy nuclear density. OCR Output One of the underlying reasons for viewing the vacuum as a physical medium is the discovery of missing symmetries. I will begin with the nonconservation of parity, or the asymmetry between right and left. ln everyday life, right and left are obviously distinct from each other. Our hearts, for example, are usually not on the right side. The word right also means "correct,' right? The word sinister in its Latin root means "left"; in Italian, "left" is sinistra. -
Arxiv:1202.1557V1
The Heisenberg-Euler Effective Action: 75 years on ∗ Gerald V. Dunne Physics Department, University of Connecticut, Storrs, CT 06269-3046, USA On this 75th anniversary of the publication of the Heisenberg-Euler paper on the full non- perturbative one-loop effective action for quantum electrodynamics I review their paper and discuss some of the impact it has had on quantum field theory. I. HISTORICAL CONTEXT After the 1928 publication of Dirac’s work on his relativistic theory of the electron [1], Heisenberg immediately appreciated the significance of the new ”hole theory” picture of the quantum vacuum of quantum electrodynamics (QED). Following some confusion, in 1931 Dirac associated the holes with positively charged electrons [2]: A hole, if there were one, would be a new kind of particle, unknown to experimental physics, having the same mass and opposite charge to an electron. With the discovery of the positron in 1932, soon thereafter [but, interestingly, not immediately [3]], Dirac proposed at the 1933 Solvay Conference that the negative energy solutions [holes] should be identified with the positron [4]: Any state of negative energy which is not occupied represents a lack of uniformity and this must be shown by observation as a kind of hole. It is possible to assume that the positrons are these holes. Positron theory and QED was born, and Heisenberg began investigating positron theory in earnest, publishing two fundamental papers in 1934, formalizing the treatment of the quantum fluctuations inherent in this Dirac sea picture of the QED vacuum [5, 6]. It was soon realized that these quantum fluctuations would lead to quantum nonlinearities [6]: Halpern and Debye have already independently drawn attention to the fact that the Dirac theory of the positron leads to the scattering of light by light, even when the energy of the photons is not sufficient to create pairs. -
Simple Model for the QCD Vacuum
A1110? 31045(3 NBSIR 83-2759 Simple Model for the QCD Vacuum U S. DEPARTMENT OF COMMERCE National Bureau of Standards Center for Radiation Research Washington, DC 20234 Centre d'Etudes de Bruyeres-le-Chatel 92542 Montrouge CEDEX, France July 1983 U S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANOAROS - - - i rx. NBSIR 83-2759 SIMPLE MODEL FOR THE QCD VACUUM m3 C 5- Michael Danos U S DEPARTMENT OF COMMERCE National Bureau of Standards Center for Radiation Research Washington, DC 20234 Daniel Gogny and Daniel Irakane Centre d'Etudes de Bruyeres-le-Chatel 92542 Montrouge CEDEX, France July 1983 U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director SIMPLE MODEL FOR THE QCD VACUUM Michael Danos, Nastional Bureau of Standards, Washington, D.C. 20234, USA and Daniel Gogny and Daniel Irakane Centre d' Etudes de Bruyeres-le-Chatel , 92542 Montrouge CEDEX, France Abstract B.v treating the high-momentum gluon and the quark sector as an in principle calculable effective Lagrangian we obtain a non-perturbati ve vacuum state for OCD as an infrdred gluon condensate. This vacuum is removed from the perturbative vacuum by an energy gap and supports a Meissner-Ochsenfeld effect. It is unstable below a minimum size and it also suggests the existence of a universal hadroni zation time. This vacuum thus exhibits all the properties required for color confinement. I. Introduction By now it is widely believed that the confinement in QCD, in analogy with superconductivity, results from the existence of a physical vacuum which is removed from the remainder of the spectrum by an energy density gap and which exhibits a Meissner-Ochsenfeld effect. -
Renormalizability of the Center-Vortex Free Sector of Yang-Mills Theory
PHYSICAL REVIEW D 101, 085007 (2020) Renormalizability of the center-vortex free sector of Yang-Mills theory † ‡ D. Fiorentini ,* D. R. Junior, L. E. Oxman , and R. F. Sobreiro § UFF—Universidade Federal Fluminense, Instituto de Física, Campus da Praia Vermelha, Avenida Litorânea s/n, 24210-346 Niterói, RJ, Brasil. (Received 11 February 2020; accepted 30 March 2020; published 17 April 2020) In this work, we analyze a recent proposal to detect SUðNÞ continuum Yang-Mills sectors labeled by center vortices, inspired by Laplacian-type center gauges in the lattice. Initially, after the introduction of appropriate external sources, we obtain a rich set of sector-dependent Ward identities, which can be used to control the form of the divergences. Next, we show the all-order multiplicative renormalizability of the center-vortex free sector. These are important steps towards the establishment of a first-principles, well-defined, and calculable Yang-Mills ensemble. DOI: 10.1103/PhysRevD.101.085007 I. INTRODUCTION was obtained in Euclidean spacetime [12,13], which provides a calculational tool similar to the one used in As is well known, the Fadeev-Popov procedure to the perturbative regime. Beyond the linear covariant quantize Yang-Mills (YM) theories [1], so successful in gauges, many efforts were also devoted to the maximal making contact with experiments at high energies, cannot Abelian gauges; see Ref. [14] and references therein. BRST be extended to the infrared regime [2,3]. In covariant invariance is an important feature to have predictive power gauges, this was established by Singer’s theorem [4]: for (renormalizability), as well as to show the independence of any gauge fixing, there are orbits with more than one gauge observables on gauge-fixing parameters. -
Vacuum Energy
Vacuum Energy Mark D. Roberts, 117 Queen’s Road, Wimbledon, London SW19 8NS, Email:[email protected] http://cosmology.mth.uct.ac.za/ roberts ∼ February 1, 2008 Eprint: hep-th/0012062 Comments: A comprehensive review of Vacuum Energy, which is an extended version of a poster presented at L¨uderitz (2000). This is not a review of the cosmolog- ical constant per se, but rather vacuum energy in general, my approach to the cosmological constant is not standard. Lots of very small changes and several additions for the second and third versions: constructive feedback still welcome, but the next version will be sometime in coming due to my sporadiac internet access. First Version 153 pages, 368 references. Second Version 161 pages, 399 references. arXiv:hep-th/0012062v3 22 Jul 2001 Third Version 167 pages, 412 references. The 1999 PACS Physics and Astronomy Classification Scheme: http://publish.aps.org/eprint/gateway/pacslist 11.10.+x, 04.62.+v, 98.80.-k, 03.70.+k; The 2000 Mathematical Classification Scheme: http://www.ams.org/msc 81T20, 83E99, 81Q99, 83F05. 3 KEYPHRASES: Vacuum Energy, Inertial Mass, Principle of Equivalence. 1 Abstract There appears to be three, perhaps related, ways of approaching the nature of vacuum energy. The first is to say that it is just the lowest energy state of a given, usually quantum, system. The second is to equate vacuum energy with the Casimir energy. The third is to note that an energy difference from a complete vacuum might have some long range effect, typically this energy difference is interpreted as the cosmological constant. -
Quantum Optics Properties of QCD Vacuum
EPJ Web of Conferences 164, 07030 (2017) DOI: 10.1051/epjconf/201716407030 ICNFP 2016 EPJ Web of Conferences will be set by the publisher DOI: will be set by the publisher c Owned by the authors, published by EDP Sciences, 2016 Quantum Optics Properties of QCD Vacuum V. Kuvshinov1,a, V. Shaparau1,b, E. Bagashov1,c 1Joint Institute for Power and Nuclear Research - Sosny National Academy of Science of Belarus PO box 119, 220109 Minsk, BELARUS Abstract. Theoretical justification of the occurrence of multimode squeezed and entan- gled colour states in QCD is given. We show that gluon entangled states which are closely related with corresponding squeezed states can appear by the four-gluon self-interaction. Correlations for the collinear gluons are revealed two groups of the colour correlations which is significant at consider of the quark-antiquark pair productions. It is shown that the interaction of colour quark with the stochastic vacuum of QCD leads to the loss of information on the initial colour state of the particle, which gives a new perspective regarding the confinement of quarks phenomenon. The effect is demonstrated for a single particle and in the multiparticle case is proposed. Quantum characteristics (purity and von Neumann entropy) are used to analyse the pro- cess of interaction. 1 Introduction + Many experiments at e e−, pp¯, ep colliders are devoted to hadronic jet physics, since detailed studies of jets are important for better understanding and testing both perturbative and non-perturbative QCD and also for finding manifestations of new physics. Although the nature of jets is of a universal + character, e e−- annihilation stands out among hard processes, since jet events admit a straightforward and clear-cut separation in this process. -
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EPJ Web of Conferences 245, 06009 (2020) https://doi.org/10.1051/epjconf/202024506009 CHEP 2019 Emergent Structure in QCD James Biddle1;∗, Waseem Kamleh1;∗∗, and Derek Leinweber1;∗∗∗ 1Centre for the Subatomic Structure of Matter, Department of Physics, The University of Adelaide, SA 5005, Australia Abstract. The structure of the SU(3) gauge-field vacuum is explored through visualisations of centre vortices and topological charge density. Stereoscopic visualisations highlight interesting features of the vortex vacuum, especially the frequency with which singular points appear and the important connection between branching points and topological charge. This work demonstrates how visualisations of the QCD ground-state fields can reveal new perspectives of centre-vortex structure. 1 Introduction Quantum Chromodynamics (QCD) is the fundamental relativistic quantum field theory un- derpinning the strong interactions of nature. The gluons of QCD carry colour charge and self-couple. This self-coupling makes the empty vacuum unstable to the formation of non- trivial quark and gluon condensates. These non-trivial ground-state “QCD-vacuum” field configurations form the foundation of matter. There are eight chromo-electric and eight chromo-magnetic fields composing the QCD vacuum. An stereoscopic illustration of one of these chromo-magnetic fields is provided in Fig. 1. Animations of the fields are also available [1–3]. The essential, fundamentally-important, nonperturbative features of the QCD vacuum fields are the dynamical generation of mass through chiral symmetry breaking, and the con- finement of quarks. But what is the fundamental mechanism of QCD that underpins these phenomena? What aspect of the QCD vacuum causes quarks to be confined? Which aspect is responsible for dynamical mass generation? Do the underlying mechanisms share a common origin? One of the most promising candidates is the centre vortex perspective [4, 5]. -
Center Vortex Detection in Smooth Lattice Configurations
Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 25 March 2021 doi:10.20944/preprints202103.0615.v1 Article A POSSIBLE RESOLUTION TO TROUBLES OF SU(2) CENTER VORTEX DETECTION IN SMOOTH LATTICE CONFIGURATIONS Rudolf Golubich ∗ , Manfried Faber Atominstitut, Technische Universität Wien; 1040 Wien; Austria * [email protected] 1 Abstract: The center vortex model of quantum-chromodynamics can explain confinement and chiral 2 symmetry breaking. We present a possible resolution for problems of the vortex detection in 3 smooth configurations and discuss improvements for the detection of center vortices. 4 Keywords: quantum chromodynamics; confinement; center vortex model; vacuum structure; 5 cooling 6 PACS: 11.15.Ha, 12.38.Gc 7 1. Introduction 8 The center vortex model of Quantum Chromodynamics [1,2] explains confinement [3] 9 and chiral symmetry breaking [4–6] by the assumption that the relevant excitations 10 of the QCD vacuum are Center vortices: Closed color magnetic flux lines evolving in 11 time. In four dimensional space-time these closed flux lines form closed surfaces in 12 dual space, see Figure1. In the low temperature phase they percolate space-time in all dimensions. Within lattice simulations the center vortices are detected in maximal center Citation: Golubich, R.; Faber, M. Title. Universe 2021, 1, 0. https://doi.org/ Received: Accepted: Published: Publisher’s Note: MDPI stays neu- tral with regard to jurisdictional claims in published maps and insti- Figure 1. left) After transformation to maximal center gauge and projection to the center degrees of tutional affiliations. freedom, a flux line can be traced by following non-trivial plaquettes. -
Baryonic Hybrids: Gluons As Beads on Strings Between Quarks
UCLA UCLA Previously Published Works Title Baryonic hybrids: Gluons as beads on strings between quarks Permalink https://escholarship.org/uc/item/1r43x573 Journal Physical Review D, 71(5) ISSN 0556-2821 Author Cornwall, J M Publication Date 2005-03-01 Peer reviewed eScholarship.org Powered by the California Digital Library University of California PHYSICAL REVIEW D 71, 056002 (2005) Baryonic hybrids: Gluons as beads on strings between quarks John M. Cornwall* Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA (Received 20 December 2004; published 8 March 2005) In this paper we analyze the ground state of the heavy-quark qqqG system using standard principles of quark confinement and massive constituent gluons as established in the center-vortex picture. The known string tension KF and approximately-known gluon mass M lead to a precise specification of the long- range nonrelativistic part of the potential binding the gluon to the quarks with no undetermined phenomenological parameters, in the limit of large interquark separation R. Our major tool (also used earlier by Simonov) is the use of proper-time methods to describe gluon propagation within the quark system, along with some elementary group theory describing the gluon Wilson-line as a composite of colocated q and q lines. We show that (aside from color-Coulomb and similar terms) the gluon potential energy in the presence of quarks is accurately described (for small gluon fluctuations) via attaching these three strings to the gluon, which in equilibrium sits at the Steiner point of the Y-shaped string network joining the three quarks. -
Marc Scott Four Forces of Nature How Strong Is the Strong Force? the Vacuum Isn't Empty Understanding the QCD Vacuum Holography
TheThe StrangeStrange WorldWorld ofof thethe Marc Scott StrongStrong ForceForce STAG Research Centre & Physics and Astronomy UnderstandingUnderstanding whywhy thethe vacuumvacuum isn'tisn't soso emptyempty Su(ervisor: Prof. Nick Evans AA goodgood wayway toto trytry andand understandunderstand thethe QCDQCD vacuumvacuum isis toto simplifysimplify thethe FourFour forcesforces ofof naturenature UnderstandingUnderstanding situationsituation toto aa twotwo quarkquark QCD,QCD, i.e.i.e. thethe twotwo lightestlightest -- upup (u)(u) andand downdown (d).(d). SinceSince thethe vacuumvacuum inin QCDQCD isis aa seethingseething realmrealm ofof quark-anti-quarkquark-anti-quark (( )) Im%!e- /.01NASA time thethe QCDQCD vacuumvacuum pairspairs –– withwith onlyonly twotwo quarksquarks toto choosechoose fromfrom (u(u oror d),d), therethere areare onlyonly 44 BIG combinationscombinations toto pick;pick; BANG GRAVITYGRAVITY Orbits. Downhill Movement. Bin in! o" #$%r&s insi e n$'leons. EachEach ofof thethe fourfour possiblepossible combinationscombinations hashas aa certaincertain probabilityprobability givengiven byby thethe vacuum,vacuum, Bin in! o" n$'lei. whichwhich variesvaries inin space.space. WeWe cancan representrepresent thisthis onon 4-dimensional4-dimensional grid,grid, eacheach axisaxis beingbeing aa Were all the N$'le%r (ower. forces of nature STRONGSTRONG combination.combination. EachEach locationlocation inin spacespace isis givengiven anan arrowarrow whichwhich isis placedplaced inin thethe 4-D4-D grid,grid, united at the thethe moremore thethe arrowarrow pointspoints inin thethe directiondirection ofof aa givengiven combinationcombination thethe moremore probableprobable beginning of the itit isis (see(see diagram).diagram). universe? Bet% De'%). In fact the vacuum is a little more WEAKWEAK The usual method for analysing interacting systems is constrained. In order to obtain the lowest TheThe usualusual methodmethod forfor analysinganalysing interactinginteracting systemssystems isis perturbation theory, but this relies on the strength of M%!netism. -
Von Smekal, Lorenz Johann
PUBLISHED VERSION Bowman, Patrick Oswald; Langfeld, Kurt; Leinweber, Derek Bruce; Sternbeck, André; von Smekal, Lorenz Johann Maria; Williams, Anthony Gordon Role of center vortices in chiral symmetry breaking in SU(3) gauge theory Physical Review D, 2011; 84(3):034501 ©2011 American Physical Society http://link.aps.org/doi/10.1103/PhysRevD.84.034501 PERMISSIONS http://publish.aps.org/authors/transfer-of-copyright-agreement http://link.aps.org/doi/10.1103/PhysRevD.62.093023 “The author(s), and in the case of a Work Made For Hire, as defined in the U.S. Copyright Act, 17 U.S.C. §101, the employer named [below], shall have the following rights (the “Author Rights”): [...] 3. The right to use all or part of the Article, including the APS-prepared version without revision or modification, on the author(s)’ web home page or employer’s website and to make copies of all or part of the Article, including the APS-prepared version without revision or modification, for the author(s)’ and/or the employer’s use for educational or research purposes.” th 7 June 2013 http://hdl.handle.net/2440/70896 PHYSICAL REVIEW D 84, 034501 (2011) Role of center vortices in chiral symmetry breaking in SU(3) gauge theory Patrick O. Bowman,1 Kurt Langfeld,2 Derek B. Leinweber,3 Andre´ Sternbeck,3,4 Lorenz von Smekal,3,5 and Anthony G. Williams3 1Centre for Theoretical Chemistry and Physics, and Institute of Natural Sciences, Massey University (Albany), Private Bag 102904, North Shore MSC, New Zealand 2School of Maths & Stats, University of Plymouth, Plymouth, PL4 8AA, England 3Centre for the Subatomic Structure of Matter (CSSM), School of Chemistry & Physics, University of Adelaide 5005, Australia 4Institut fu¨r Theoretische Physik, Universita¨t Regensburg, D-93040 Regensburg, Germany 5Institut fu¨r Kernphysik, Technische Universita¨t Darmstadt, D-64289 Darmstadt, Germany (Received 25 October 2010; published 4 August 2011) We study the behavior of the AsqTad quark propagator in Landau gauge on SU(3) Yang-Mills gauge configurations under the removal of center vortices.