Twenty Five Years of Asymptotic Freedom
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Asymptotic Freedom, Quark Confinement, Proton Spin Crisis, Neutron Structure, Dark Matters, and Relative Force Strengths
Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 17 February 2021 doi:10.20944/preprints202102.0395.v1 Asymptotic freedom, quark confinement, proton spin crisis, neutron structure, dark matters, and relative force strengths Jae-Kwang Hwang JJJ Physics Laboratory, Brentwood, TN 37027 USA Abstract: The relative force strengths of the Coulomb forces, gravitational forces, dark matter forces, weak forces and strong forces are compared for the dark matters, leptons, quarks, and normal matters (p and n baryons) in terms of the 3-D quantized space model. The quark confinement and asymptotic freedom are explained by the CC merging to the A(CC=-5)3 state. The proton with the (EC,LC,CC) charge configuration of p(1,0,-5) is p(1,0) + A(CC=-5)3. The A(CC=-5)3 state has the 99.6% of the proton mass. The three quarks in p(1,0,-5) are asymptotically free in the EC and LC space of p(1,0) and are strongly confined in the CC space of A(CC=-5)3. This means that the lepton beams in the deep inelastic scattering interact with three quarks in p(1,0) by the EC interaction and weak interaction. Then, the observed spin is the partial spin of p(1,0) which is 32.6 % of the total spin (1/2) of the proton. The A(CC=-5)3 state has the 67.4 % of the proton spin. This explains the proton spin crisis. The EC charge distribution of the proton is the same to the EC charge distribution of p(1,0) which indicates that three quarks in p(1,0) are mostly near the proton surface. -
Old Soldiers by Michael Riordan
Old soldiers by Michael Riordan Twenty years ago this month, an this deep inelastic region in excru experiment began at the Stanford ciating detail, the new quark-parton Linear Accelerator Center in Cali picture of a nucleon's innards fornia that would eventually redraw gradually took a firmer and firmer the map of high energy physics. hold upon the particle physics com In October 1967, MIT and SLAC munity. These two massive spec physicists started shaking down trometers were our principal 'eyes' their new 20 GeV spectrometer; into the new realm, by far the best by mid-December they were log ones we had until more powerful ging electron-proton scattering in muon and neutrino beams became the so-called deep inelastic region available at Fermilab and CERN. where the electrons probed deep They were our Geiger and Marsd- inside the protons. The huge ex en, reporting back to Rutherford cess of scattered electrons they the detailed patterns of ricocheting encountered there-about ten times projectiles. Through their magnetic the expected rate-was later inter lenses we 'observed' quarks for preted as evidence for pointlike, the very first time, hard 'pits' inside fractionally charged objects inside hadrons. the proton. These two goliaths stood reso Michael Riordan (above) did The quarks we take for granted lutely at the front as a scientific research using the 8 GeV today were at best 'mathematical' revolution erupted all about them spectrometer at SLAC as an entities in 1967 - if one allowed during the late 1960s and early MIT graduate student during them any true existence at all. -
Hep-Th/9609099V1 11 Sep 1996 ⋆ † Eerhspotdi Atb O Rn DE-FG02-90ER40542
IASSNS 96/95 hep-th/9609099 September 1996 ⋆ Asymptotic Freedom Frank Wilczek† School of Natural Sciences Institute for Advanced Study Olden Lane Princeton, N.J. 08540 arXiv:hep-th/9609099v1 11 Sep 1996 ⋆ Lecture on receipt of the Dirac medal for 1994, October 1994. Research supported in part by DOE grant DE-FG02-90ER40542. [email protected] † ABSTRACT I discuss how the basic phenomenon of asymptotic freedom in QCD can be un- derstood in elementary physical terms. Similarly, I discuss how the long-predicted phenomenon of “gluonization of the proton” – recently spectacularly confirmed at HERA – is a rather direct manifestation of the physics of asymptotic freedom. I review the broader significance of asymptotic freedom in QCD in fundamental physics: how on the one hand it guides the interpretation and now even the design of experiments, and how on the other it makes possible a rational, quantitative theoretical approach to problems of unification and early universe cosmology. 2 I am very pleased to accept your award today. On this occasion I think it is appropriate to discuss with you the circle of ideas around asymptotic freedom. After a few remarks about its setting in intellectual history, I will begin by ex- plaining the physical origin of asymptotic freedom in QCD; then I will show how a recent, spectacular experimental observation – the ‘gluonization’ of the proton – both confirms and illuminates its essential nature; then I will discuss some of its broader implications for fundamental physics. It may be difficult for young people who missed experiencing it, or older people with fading memories, fully to imagine the intellectual atmosphere surrounding the strong interaction in the 1960s and early 1970s. -
1 Introduction
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server 1 TWENTY FIVE YEARS OF ASYMPTOTIC FREEDOM David J. Gross Institute For Theoretical Physics, UCSB Santa Barbara, California, USA e-mail: [email protected] Abstract th On the o ccasion of the 25 anniversary of Asymptotic Freedom, celebrated at the QCD Euorconference 98 on Quantum Chro dynamics, Montp ellier, July 1998, I describ ed the discovery of Asymptotic Freedom and the emergence of QCD. 1 INTRODUCTION Science progresses in a much more muddled fashion than is often pictured in history b o oks. This is esp ecially true of theoretical physics, partly b ecause history is written by the victorious. Con- sequently, historians of science often ignore the many alternate paths that p eople wandered down, the many false clues they followed, the many misconceptions they had. These alternate p oints of view are less clearly develop ed than the nal theories, harder to understand and easier to forget, esp ecially as these are viewed years later, when it all really do es make sense. Thus reading history one rarely gets the feeling of the true nature of scienti c development, in which the element of farce is as great as the element of triumph. The emergence of QCD is a wonderful example of the evolution from farce to triumph. During a very short p erio d, a transition o ccurred from exp erimental discovery and theoretical confusion to theoretical triumph and exp erimental con rmation. In trying to relate this story, one must be wary of the danger of the p ersonal bias that o ccurs as one lo oks back in time. -
July 2007 (Volume 16, Number 7) Entire Issue
July 2007 Volume 16, No. 7 www.aps.org/publications/apsnews APS NEWS Election Preview A PUBLICATION OF THE AMERICAN PHYSICAL SOCIETY • WWW.apS.ORG/PUBLICATIONS/apSNEWS Pages 6-7 Executive Board Resolution Thanks US physics team trains for competition in Iran By Katherine McAlpine Legislators for Support of Science Twenty-four high school stu- The APS Executive Board bill authorizes nearly $60 billion dents comprising the US Phys- has passed a resolution thanking for various programs for FY 2008 ics Olympiad team vied for five House and Senate policy makers through FY 2011. The bill would places on the traveling team at for recently-passed legislation double the NSF budget over five the University of Maryland from that strengthens the science, math years and double the DOE Office May 22nd to June 1st. Those and engineering activities of our of Science budget over 10 years. chosen to travel will compete nation. The House of Representatives this month against teams from “Sustaining and improving the passed five separate authorization all over the world at Isfahan standard of living of American bills, which were then combined University of Technology in Is- citizens, achieving energy security into one bill, H.R. 2272, the 21st fahan, Iran. and environmental sustainability, Century Competitiveness Act of Over 3,100 US Physics Team providing the jobs of tomorrow 2007. The bill would put the NSF hopefuls took the preliminary and defending our nation against budget and the NIST Scientific examination in January, and 200 aggressors all require federal in- and Technical Research and Ser- were given a second exam in vestments in science education vices budget on track to double in March to determine the top 24 and research… The Board con- 10 years. -
Quantum Mechanics Quantum Chromodynamics (QCD)
Quantum Mechanics_quantum chromodynamics (QCD) In theoretical physics, quantum chromodynamics (QCD) is a theory ofstrong interactions, a fundamental forcedescribing the interactions between quarksand gluons which make up hadrons such as the proton, neutron and pion. QCD is a type of Quantum field theory called a non- abelian gauge theory with symmetry group SU(3). The QCD analog of electric charge is a property called 'color'. Gluons are the force carrier of the theory, like photons are for the electromagnetic force in quantum electrodynamics. The theory is an important part of the Standard Model of Particle physics. A huge body of experimental evidence for QCD has been gathered over the years. QCD enjoys two peculiar properties: Confinement, which means that the force between quarks does not diminish as they are separated. Because of this, when you do split the quark the energy is enough to create another quark thus creating another quark pair; they are forever bound into hadrons such as theproton and the neutron or the pion and kaon. Although analytically unproven, confinement is widely believed to be true because it explains the consistent failure of free quark searches, and it is easy to demonstrate in lattice QCD. Asymptotic freedom, which means that in very high-energy reactions, quarks and gluons interact very weakly creating a quark–gluon plasma. This prediction of QCD was first discovered in the early 1970s by David Politzer and by Frank Wilczek and David Gross. For this work they were awarded the 2004 Nobel Prize in Physics. There is no known phase-transition line separating these two properties; confinement is dominant in low-energy scales but, as energy increases, asymptotic freedom becomes dominant. -
Color Screening in Quantum Chromodynamics Arxiv
Color Screening in Quantum Chromodynamics Alexei Bazavov, Johannes H. Weber Department of Computational Mathematics, Science and Engineering and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA October 6, 2020 Abstract We review lattice studies of the color screening in the quark-gluon plasma. We put the phenomena related to the color screening into the context of similar aspects of other physical systems (electromag- netic plasma or cold nuclear matter). We discuss the onset of the color screening and its signature and significance in the QCD transi- tion region, and elucidate at which temperature and to which extent the weak-coupling picture based on hard thermal loop expansion, po- tential nonrelativistic QCD, or dimensionally-reduced QCD quantita- tively captures the key properties of the color screening. We discuss the different regimes pertaining to the color screening and thermal arXiv:2010.01873v1 [hep-lat] 5 Oct 2020 dissociation of the static quarks in depth for various spatial correla- tion functions that are studied on the lattice, and clarify the status of their asymptotic screening masses. We finally discuss the screening correlation functions of dynamical mesons with a wide range of flavor and spin content, and how they conform with expectations for low- and high-temperature behavior. 1 Contents 1 Introduction3 2 Field theoretical foundations7 2.1 Partition function and Lagrangian . .7 2.2 Finite temperature field theory . 11 2.3 Lattice regularization . 14 2.4 Renormalization and weak coupling . 17 2.5 Light quarks . 19 2.6 Heavy quarks . 21 2.7 Implementation of QCD on the lattice . -
Iasinstitute for Advanced Study
IAInsti tSute for Advanced Study Faculty and Members 2012–2013 Contents Mission and History . 2 School of Historical Studies . 4 School of Mathematics . 21 School of Natural Sciences . 45 School of Social Science . 62 Program in Interdisciplinary Studies . 72 Director’s Visitors . 74 Artist-in-Residence Program . 75 Trustees and Officers of the Board and of the Corporation . 76 Administration . 78 Past Directors and Faculty . 80 Inde x . 81 Information contained herein is current as of September 24, 2012. Mission and History The Institute for Advanced Study is one of the world’s leading centers for theoretical research and intellectual inquiry. The Institute exists to encourage and support fundamental research in the sciences and human - ities—the original, often speculative thinking that produces advances in knowledge that change the way we understand the world. It provides for the mentoring of scholars by Faculty, and it offers all who work there the freedom to undertake research that will make significant contributions in any of the broad range of fields in the sciences and humanities studied at the Institute. Y R Founded in 1930 by Louis Bamberger and his sister Caroline Bamberger O Fuld, the Institute was established through the vision of founding T S Director Abraham Flexner. Past Faculty have included Albert Einstein, I H who arrived in 1933 and remained at the Institute until his death in 1955, and other distinguished scientists and scholars such as Kurt Gödel, George F. D N Kennan, Erwin Panofsky, Homer A. Thompson, John von Neumann, and A Hermann Weyl. N O Abraham Flexner was succeeded as Director in 1939 by Frank Aydelotte, I S followed by J. -
Asymptotic Freedom and Higher Derivative Gauge Theories Arxiv
Asymptotic freedom and higher derivative gauge theories M. Asoreya F. Falcetoa L. Rachwałb aCentro de Astropartículas y Física de Altas Energías, Departamento de Física Teórica Universidad de Zaragoza, C/ Pedro Cerbuna 12, E-50009 Zaragoza, Spain bDepartamento de Física – ICE, Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, Campus Universitário, Juiz de Fora, 36036-900, MG, Brazil E-mail: [email protected], [email protected], [email protected] Abstract: The ultraviolet completion of gauge theories by higher derivative terms can dramatically change their behavior at high energies. The requirement of asymp- totic freedom imposes very stringent constraints that are only satisfied by a small family of higher derivative theories. If the number of derivatives is large enough (n > 4) the theory is strongly interacting both at extreme infrared and ultraviolet regimes whereas it remains asymptotically free for a low number of extra derivatives (n 6 4). In all cases the theory improves its ultraviolet behavior leading in some cases to ultraviolet finite theories with vanishing β-function. The usual consistency problems associated to the presence of extra ghosts in higher derivative theories may not harm asymptotically free theories because in that case the effective masses of such ghosts are running to infinity in the ultraviolet limit. Keywords: gauge theories, renormalization group, higher derivatives regulariza- tion, asymptotic freedom arXiv:2012.15693v3 [hep-th] 11 May 2021 1 Introduction Field theories with higher derivatives were first considered as covariant ultraviolet regularizations of gauge theories [1]-[3]. However, in the last years there is a renewed interest in these theories mainly due to the rediscovery that they provide a renormal- izable field theoretical framework for the quantization of gravity [4,5]. -
The Struggle for Quantum Theory 47 5.1Aliensignals
Fundamental Forces of Nature The Story of Gauge Fields This page intentionally left blank Fundamental Forces of Nature The Story of Gauge Fields Kerson Huang Massachusetts Institute of Technology, USA World Scientific N E W J E R S E Y • L O N D O N • S I N G A P O R E • B E I J I N G • S H A N G H A I • H O N G K O N G • TA I P E I • C H E N N A I Published by World Scientific Publishing Co. Pte. Ltd. 5 Toh Tuck Link, Singapore 596224 USA office: 27 Warren Street, Suite 401-402, Hackensack, NJ 07601 UK office: 57 Shelton Street, Covent Garden, London WC2H 9HE British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. FUNDAMENTAL FORCES OF NATURE The Story of Gauge Fields Copyright © 2007 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. This book, or parts thereof, may not be reproduced in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system now known or to be invented, without written permission from the Publisher. For photocopying of material in this volume, please pay a copying fee through the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, USA. In this case permission to photocopy is not required from the publisher. ISBN-13 978-981-270-644-7 ISBN-10 981-270-644-5 ISBN-13 978-981-270-645-4 (pbk) ISBN-10 981-270-645-3 (pbk) Printed in Singapore. -
Exploring the Fundamental Properties of Matter with an Electron-Ion Collider
Exploring the fundamental properties of matter with an Electron-Ion Collider Jianwei Qiu Theory Center, Jefferson Lab Acknowledgement: Much of the physics presented here are based on the work of EIC White Paper Writing Committee put together by BNL and JLab managements, … Eternal Questions People have long asked Where did we come from? The Big Bang theory? What is the world made of? Basic building blocks? What holds it together? Fundamental forces? Where are we going to? The future? Where did we come from? Can we go back in time or recreate the condition of early universe? Going back in time? Expansion of the universe Little Bang in the Laboratory Create a matter (QGP) with similar temperature and energy density BNL - RHIC CERN - LHC Gold - Gold Lead - Lead Relativistic heavy-ion collisions – the little bang q A virtual Journey of Visible Matter: Lorentz Near Quark-gluon Seen contraction collision plasma Hadronization Freeze-out in the detector q Discoveries – Properties of QGP: ² A nearly perfect quantum fluid – NOT a gas! at 4 trillion degrees Celsius, Not, at 10-5 K like 6Li q Questions: ² How the observed particles were emerged (after collision)? Properties of ² Does the initial condition matter (before collision)? visible matter What the world is made of? Human is only a tiny part of the universe But, human is exploring the whole universe! What hold it together? q Science and technology: Particle & Nuclear Physics Nucleon: Proton, or Neutron Nucleon – building block of all atomic matter q Our understanding of the nucleon evolves 1970s -
Basics of QCD for the LHC
Basics of QCD for the LHC Lecture I Fabio Maltoni Center for Particle Physics and Phenomenology (CP3) Université Catholique de Louvain 2011 School of High-Energy Physics 1 Fabio Maltoni Claims and Aims LHC is live and kicking!!!! There has been a number of key theoretical results recently in the quest of achieving the best possible predictions and description of events at the LHC. Perturbative QCD applications to LHC physics in conjunction with Monte Carlo developments are VERY active lines of theoretical research in particle phenomenology. In fact, new dimensions have been added to Theory ⇔ Experiment interactions 2011 School of High-Energy Physics 2 Fabio Maltoni Claims and Aims Five lectures: 1. Intro and QCD fundamentals 2. QCD in the final state basics 3. QCD in the initial state 4. From accurate QCD to useful QCD 5. Advanced QCD with applications at the LHC apps 2011 School of High-Energy Physics 3 Fabio Maltoni Claims and Aims • perspective: the big picture • concepts: QCD from high-Q2 to low-Q2, asymptotic freedom, infrared safety, factorization • tools & techniques: Fixed Order (FO) computations, Parton showers, Monte Carlo’s (MC) • recent progress: merging MC’s with FO, new jet algorithms • sample applications at the LHC: Drell-Yan, Higgs, Jets, BSM,... 2011 School of High-Energy Physics 4 Fabio Maltoni Claims and (your) Aims Think Ask Work Mathematica notebooks on a “simple” NLO calculation and other exercises on QCD applications to LHC phenomenology available on the MadGraph Wiki. http://cp3wks05.fynu.ucl.ac.be/twiki/bin/view/Physics/CernSchool2011 2011 School of High-Energy Physics 5 Fabio Maltoni Minimal References • Ellis, Stirling and Webber: The Pink Book • Excellent lectures on the archive by M.