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CERN Courier–Digital Edition
CERNMarch/April 2021 cerncourier.com COURIERReporting on international high-energy physics WELCOME CERN Courier – digital edition Welcome to the digital edition of the March/April 2021 issue of CERN Courier. Hadron colliders have contributed to a golden era of discovery in high-energy physics, hosting experiments that have enabled physicists to unearth the cornerstones of the Standard Model. This success story began 50 years ago with CERN’s Intersecting Storage Rings (featured on the cover of this issue) and culminated in the Large Hadron Collider (p38) – which has spawned thousands of papers in its first 10 years of operations alone (p47). It also bodes well for a potential future circular collider at CERN operating at a centre-of-mass energy of at least 100 TeV, a feasibility study for which is now in full swing. Even hadron colliders have their limits, however. To explore possible new physics at the highest energy scales, physicists are mounting a series of experiments to search for very weakly interacting “slim” particles that arise from extensions in the Standard Model (p25). Also celebrating a golden anniversary this year is the Institute for Nuclear Research in Moscow (p33), while, elsewhere in this issue: quantum sensors HADRON COLLIDERS target gravitational waves (p10); X-rays go behind the scenes of supernova 50 years of discovery 1987A (p12); a high-performance computing collaboration forms to handle the big-physics data onslaught (p22); Steven Weinberg talks about his latest work (p51); and much more. To sign up to the new-issue alert, please visit: http://comms.iop.org/k/iop/cerncourier To subscribe to the magazine, please visit: https://cerncourier.com/p/about-cern-courier EDITOR: MATTHEW CHALMERS, CERN DIGITAL EDITION CREATED BY IOP PUBLISHING ATLAS spots rare Higgs decay Weinberg on effective field theory Hunting for WISPs CCMarApr21_Cover_v1.indd 1 12/02/2021 09:24 CERNCOURIER www. -
Elementary Explanation of the Inexistence of Decoherence at Zero
Elementary explanation of the inexistence of decoherence at zero temperature for systems with purely elastic scattering Yoseph Imry Dept. of Condensed-Matter Physics, the Weizmann Institute of science, Rehovot 76100, Israel (Dated: October 31, 2018) This note has no new results and is therefore not intended to be submitted to a ”research” journal in the foreseeable future, but to be available to the numerous individuals who are interested in this issue. Several of those have approached the author for his opinion, which is summarized here in a hopefully pedagogical manner, for convenience. It is demonstrated, using essentially only energy conservation and elementary quantum mechanics, that true decoherence by a normal environment approaching the zero-temperature limit is impossible for a test particle which can not give or lose energy. Prime examples are: Bragg scattering, the M¨ossbauer effect and related phenomena at zero temperature, as well as quantum corrections for the transport of conduction electrons in solids. The last example is valid within the scattering formulation for the transport. Similar statements apply also to interference properties in equilibrium. PACS numbers: 73.23.Hk, 73.20.Dx ,72.15.Qm, 73.21.La I. INTRODUCTION cally in the case of the coupling of a conduction-electron in a solid to lattice vibrations (phonons) 14 years ago [5] and immediately refuted vigorously [6]. Interest in this What diminishes the interference of, say, two waves problem has resurfaced due to experiments by Mohanty (see Eq. 1 below) is an interesting fundamental ques- et al [7] which determine the dephasing rate of conduc- tion, some aspects of which are, surprisingly, still being tion electrons by weak-localization magnetoconductance debated. -
Accommodating Retrocausality with Free Will Yakir Aharonov Chapman University, [email protected]
Chapman University Chapman University Digital Commons Mathematics, Physics, and Computer Science Science and Technology Faculty Articles and Faculty Articles and Research Research 2016 Accommodating Retrocausality with Free Will Yakir Aharonov Chapman University, [email protected] Eliahu Cohen Tel Aviv University Tomer Shushi University of Haifa Follow this and additional works at: http://digitalcommons.chapman.edu/scs_articles Part of the Quantum Physics Commons Recommended Citation Aharonov, Y., Cohen, E., & Shushi, T. (2016). Accommodating Retrocausality with Free Will. Quanta, 5(1), 53-60. doi:http://dx.doi.org/10.12743/quanta.v5i1.44 This Article is brought to you for free and open access by the Science and Technology Faculty Articles and Research at Chapman University Digital Commons. It has been accepted for inclusion in Mathematics, Physics, and Computer Science Faculty Articles and Research by an authorized administrator of Chapman University Digital Commons. For more information, please contact [email protected]. Accommodating Retrocausality with Free Will Comments This article was originally published in Quanta, volume 5, issue 1, in 2016. DOI: 10.12743/quanta.v5i1.44 Creative Commons License This work is licensed under a Creative Commons Attribution 3.0 License. This article is available at Chapman University Digital Commons: http://digitalcommons.chapman.edu/scs_articles/334 Accommodating Retrocausality with Free Will Yakir Aharonov 1;2, Eliahu Cohen 1;3 & Tomer Shushi 4 1 School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel. E-mail: [email protected] 2 Schmid College of Science, Chapman University, Orange, California, USA. E-mail: [email protected] 3 H. H. Wills Physics Laboratory, University of Bristol, Bristol, UK. -
Chairman of the Opening Session
The Universe had (probably) an origin: on singularity theorems & quantum fluctuations Emilio Elizalde ICE/CSIC & IEEC Campus UAB, Barcelona Cosmology and the Quantum Vacuum III, Benasque, Sep 4-10, 2016 Some facts (a few rather surprising...) • Adam Riess, NP 2011, at Starmus (Tenerife), about Hubble: • “Hubble obtained the distances and redshifts of distant nebulae…” • “Hubble discovered that the Universe was expanding…” • No mention to Vesto Slipher, an extraordinary astronomer • Brian Schmidt, NP 2011, at Starmus (Tenerife) & Lisa Randall, Harvard U, in Barcelona, about Einstein: SHOES- • “Einstein was the first to think about the possibility of a ‘dark energy’…” Supernovae • No mention to Fritz Zwicky, another extraordinary astronomer • Fritz Zwicky discovered dark matter in the early 1930s while studying how galaxies move within the Coma Cluster • He was also the first to postulate and use nebulae as gravitational lenses (1937) • How easily* brilliant astronomers get dismissed • How easily* scientific myths arise *in few decades How did the “Big Bang” get its name ? http://www.bbc.co.uk/science/space/universe/scientists/fred_hoyle • Sir Fred Hoyle (1915–2001) English astronomer noted primarily for the theory of stellar nucleosynthesis (1946,54 groundbreaking papers) • Work on Britain's radar project with Hermann Bondi and Thomas Gold • William Fowler NP’83: “The concept of nucleosynthesis in stars was first established by Hoyle in 1946” • He found the idea universe had a beginning to be pseudoscience, also arguments for a creator, “…for it's an irrational process, and can't be described in scientific terms”; “…belief in the first page of Genesis” • Hoyle-Gold-Bondi 1948 steady state theory, “creation or C-field” • BBC radio's Third Programme broadcast on 28 Mar 1949: “… for this to happen you would need such a Big Bang!” Thus: Big Bang = Impossible blow!! But now: Big Bang ≈ Inflation ! • Same underlying physics as in steady state theory, “creation or C-field” • Richard C. -
What Is the Universe Made Of? How Old Is the Universe?
What is the Universe made of? How old is it? Charles H. Lineweaver University of New South Wales ABSTRACT For the past 15 years most astronomers have assumed that 95% of the Universe was in some mysterious form of cold dark matter. They also assumed that the cosmo- logical constant, ΩΛ, was Einstein’s biggest blunder and could be ignored. However, recent measurements of the cosmic microwave background combined with other cos- mological observations strongly suggest that 75% of the Universe is made of cosmo- logical constant (vacuum energy), while only 20% is made of non-baryonic cold dark matter. Normal baryonic matter, the stuff most physicists study, makes up about 5% of the Universe. If these results are correct, an unknown 75% of the Universe has been identified. Estimates of the age of the Universe depend upon what it is made of. Thus, our new inventory gives us a new age for the Universe: 13.4 ± 1.6 Gyr. “The history of cosmology shows us that in every age devout people believe that they have at last discovered the true nature of the Universe.” (E. Harrison in Cosmology: The Science of the Universe 1981) 1 Progress A few decades ago cosmology was laughed at for being the only science with no data. Cosmology was theory-rich but data-poor. It attracted armchair enthusiasts spouting speculations without data to test them. It was the only science where the errors could be kept in the exponents – where you could set the speed of light c =1, not for dimensionless convenience, but because the observations were so poor that it didn’t matter. -
Geometric Phase from Aharonov-Bohm to Pancharatnam–Berry and Beyond
Geometric phase from Aharonov-Bohm to Pancharatnam–Berry and beyond Eliahu Cohen1,2,*, Hugo Larocque1, Frédéric Bouchard1, Farshad Nejadsattari1, Yuval Gefen3, Ebrahim Karimi1,* 1Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada 2Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan 5290002, Israel 3Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel *Corresponding authors: [email protected], [email protected] Abstract: Whenever a quantum system undergoes a cycle governed by a slow change of parameters, it acquires a phase factor: the geometric phase. Its most common formulations are known as the Aharonov-Bohm, Pancharatnam and Berry phases, but both prior and later manifestations exist. Though traditionally attributed to the foundations of quantum mechanics, the geometric phase has been generalized and became increasingly influential in many areas from condensed-matter physics and optics to high energy and particle physics and from fluid mechanics to gravity and cosmology. Interestingly, the geometric phase also offers unique opportunities for quantum information and computation. In this Review we first introduce the Aharonov-Bohm effect as an important realization of the geometric phase. Then we discuss in detail the broader meaning, consequences and realizations of the geometric phase emphasizing the most important mathematical methods and experimental techniques used in the study of geometric phase, in particular those related to recent works in optics and condensed-matter physics. Published in Nature Reviews Physics 1, 437–449 (2019). DOI: 10.1038/s42254-019-0071-1 1. Introduction A charged quantum particle is moving through space. -
Annual Report to Industry Canada Covering The
Annual Report to Industry Canada Covering the Objectives, Activities and Finances for the period August 1, 2008 to July 31, 2009 and Statement of Objectives for Next Year and the Future Perimeter Institute for Theoretical Physics 31 Caroline Street North Waterloo, Ontario N2L 2Y5 Table of Contents Pages Period A. August 1, 2008 to July 31, 2009 Objectives, Activities and Finances 2-52 Statement of Objectives, Introduction Objectives 1-12 with Related Activities and Achievements Financial Statements, Expenditures, Criteria and Investment Strategy Period B. August 1, 2009 and Beyond Statement of Objectives for Next Year and Future 53-54 1 Statement of Objectives Introduction In 2008-9, the Institute achieved many important objectives of its mandate, which is to advance pure research in specific areas of theoretical physics, and to provide high quality outreach programs that educate and inspire the Canadian public, particularly young people, about the importance of basic research, discovery and innovation. Full details are provided in the body of the report below, but it is worth highlighting several major milestones. These include: In October 2008, Prof. Neil Turok officially became Director of Perimeter Institute. Dr. Turok brings outstanding credentials both as a scientist and as a visionary leader, with the ability and ambition to position PI among the best theoretical physics research institutes in the world. Throughout the last year, Perimeter Institute‘s growing reputation and targeted recruitment activities led to an increased number of scientific visitors, and rapid growth of its research community. Chart 1. Growth of PI scientific staff and associated researchers since inception, 2001-2009. -
David Bohn, Roger Penrose, and the Search for Non-Local Causality
David Bohm, Roger Penrose, and the Search for Non-local Causality Before they met, David Bohm and Roger Penrose each puzzled over the paradox of the arrow of time. After they met, the case for projective physical space became clearer. *** A machine makes pairs (I like to think of them as shoes); one of the pair goes into storage before anyone can look at it, and the other is sent down a long, long hallway. At the end of the hallway, a physicist examines the shoe.1 If the physicist finds a left hiking boot, he expects that a right hiking boot must have been placed in the storage bin previously, and upon later examination he finds that to be the case. So far, so good. The problem begins when it is discovered that the machine can make three types of shoes: hiking boots, tennis sneakers, and women’s pumps. Now the physicist at the end of the long hallway can randomly choose one of three templates, a metal sheet with a hole in it shaped like one of the three types of shoes. The physicist rolls dice to determine which of the templates to hold up; he rolls the dice after both shoes are out of the machine, one in storage and the other having started down the long hallway. Amazingly, two out of three times, the random choice is correct, and the shoe passes through the hole in the template. There can 1 This rendition of the Einstein-Podolsky-Rosen, 1935, delayed-choice thought experiment is paraphrased from Bernard d’Espagnat, 1981, with modifications via P. -
Tinkering with Time the NEW TIME TRAVELERS: a JOURNEY to the on Our FRONTIERS of PHYSICS by DAVID TOOMEY Bookshelf W
BOOKS & ARTS Tinkering with time THE NEW TIME TRAVELERS: A JOURNEY TO THE On our FRONTIERS OF PHYSICS BY DAVID TOOMEY bookshelf W. W. Norton & Co.: 2007. 320 pp. $25.95 Years ago, David Toomey picked up H. G. Wells’ moving clocks tick slowly, making time travel The Time Machine and couldn’t put it down. to the future possible. We now know a number The Mathematics of He was most interested in the drawing-room of solutions to Einstein’s equations of general Egypt, Mesopotamia, discussion between the time traveller and his relativity (1915) that are sufficiently twisted to China, India, and Islam: friends in which time as a fourth dimension was allow time travel to the past: Kurt Gödel’s 1949 A Sourcebook discussed, but wanted to know more about just rotating universe; the Morris–Thorne–Yurtsever edited by Victor J. Katz how that time machine might work. Toomey was wormhole (1988); the Tipler–van Stockum infinite therefore delighted to learn that that drawing- rotating cylinder, moving cosmic strings (myself), Princeton Univ. Press: room conversation continues today — this time the rotating black-hole interior (Brandon Carter), 2007. 685 pp. $75 among physicists. a Roman ring of wormholes (Matt Visser), the We’re aware that Toomey captures well the personalities Everett–Alcubierre warp drive, my and Li–Xin Li’s the ancient cultures of the ‘new time travelers’ — those physicists self-creating universe; Amos Ori’s torus; and were mathematically interested in whether time travel to the past is others. The book discusses all of these. advanced. Now possible — from Stephen Hawking’s sense of But can a time machine really be constructed? translations of early texts humour to Kip Thorne’s penchant for placing Hawking, like one of the time traveller’s sceptical from five key regions are scientific bets. -
ACCRETION INTO and EMISSION from BLACK HOLES Thesis By
ACCRETION INTO AND EMISSION FROM BLACK HOLES Thesis by Don Nelson Page In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy California Institute of Technology Pasadena, California 1976 (Submitted May 20, 1976) -ii- ACKNOHLEDG:-IENTS For everything involved during my pursuit of a Ph. D. , I praise and thank my Lord Jesus Christ, in whom "all things were created, both in the heavens and on earth, visible and invisible, whether thrones or dominions or rulers or authorities--all things have been created through Him and for Him. And He is before all things, and in Him all things hold together" (Colossians 1: 16-17) . But He is not only the Creator and Sustainer of the universe, including the physi cal laws which rule and their dominion the spacetime manifold and its matter fields ; He is also my personal Savior, who was "wounded for our transgressions , ... bruised for our iniquities, .. and the Lord has lald on Him the iniquity of us all" (Isaiah 53:5-6). As the Apostle Paul expressed it shortly after Isaiah ' s prophecy had come true at least five hundred years after being written, "God demonstrates His own love tmvard us , in that while we were yet sinners, Christ died for us" (Romans 5 : 8) . Christ Himself said, " I have come that they may have life, and have it to the full" (John 10:10) . Indeed Christ has given me life to the full while I have been at Caltech, and I wish to acknowledge some of the main blessings He has granted: First I thank my advisors , KipS. -
2019/20 Perimeter Institute Annual Report English
2020 ANNUAL REPORT VISION To create the world’s foremost centre for research, graduate training, and educational outreach in theoretical physics, uniting public and private partners, and the world’s best scientific minds, in a shared enterprise to achieve breakthroughs that will transform our future. Estelle Inack, Jason Iaconis, and Roger Melko, October 2019 CONTENTS Message from the Board Chair .............................................2 Message from the Institute Director ......................................3 How Perimeter Measures Up ................................................4 Research ...............................................................................6 Training ................................................................................26 Outreach ..............................................................................32 Our Future is Bright .............................................................38 Advancement ......................................................................40 Governance and Finance ....................................................44 Appendices .........................................................................51 This report covers the activities and finances of Perimeter Institute for Theoretical Physics from August 1, 2019, to July 31, 2020. TODAY'S THEORETICAL PHYSICS IS TOMORROW'S TECHNOLOGY MESSAGE FROM THE BOARD CHAIR The coronavirus has made the past year very difficult. The loss transform epidemiology, finance and insurance, risk of loved ones and the economic, -
What's Inside
Newsletter A publication of the Controlled Release Society Volume 33 • Number 1 • 2016 What’s Inside Modern Drug–Medical Device Combination Products Controlled Release of Levofloxacin from Vitamin E Loaded Silicone- Hydrogel Contact Lenses Encapsulation of Gold Nanoparticles to Visualize Intracellular Localization of Lipid and Polymer-Based Nanocarriers The One Health Initiative and Its Impact on Drug Development DDTR Update Chapter News Controlled Release Society Annual Meeting & Exposition July 17–20, 2016 Seattle, Washington, U.S.A. COLLABORATE CONNECT INNOVATE Registration Opens in March! Visit controlledreleasesociety.org for the latest details. Don’t miss out on the must-attend event in delivery science and technology! This is your opportunity to: • Learn about cutting-edge research and innovation • Meet esteemed industry experts, researchers, and young scientists • Build your network and collaborate controlledreleasesociety.org Newsletter Charles Frey Vol. 33 • No. 1 • 2016 Editor > TABLE OF CONTENTS 4 From the Editor 5 Preclinical Sciences & Animal Health The One Health Initiative and Its Impact on Drug Development Steven Giannos Editor 8 Special Feature Modern Drug-Medical Device Combination Products 10 Scientifically Speaking Controlled Release of Levofloxacin from Vitamin E Loaded Silicone-Hydrogel Contact Lenses 12 Scientifically Speaking Encapsulation of Gold Nanoparticles to Visualize Intracellular Arlene McDowell Localization of Lipid and Polymer-Based Nanocarriers Editor 15 CRS Foundation 2016 Allan Hoffman Student Travel Grant Program 16 Chapter News Drug Delivery Australia 18 Chapter News Rheology: How to Get into the Flow Bozena Michniak-Kohn 20 Chapter News Editor Micro- and Nanotechnologies to Overcome Biological Barriers: Eighth Annual CRS Italy Local Chapter Workshop 22 DDTR Update Drug Delivery and Translational Research Update 24 People in the News 25 Companies in the News Yvonne Perrie Editor Cover image: ©krugloff / Shutterstock.com Rod Walker Editor 3 > FROM THE EDITOR Editors Charles Frey Steven Giannos Roderick B.