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Not Even Wrong, Ten Years Later: a View from Mathematics on Prospects for Fundamental Physics Without Experiment
Not Even Wrong, ten years later: a view from mathematics on prospects for fundamental physics without experiment Peter Woit Columbia University Rutgers Physics Colloquium, February 3, 2016 Peter Woit (Columbia University) Not Even Wrong, ten years later: a view from mathematicsFebruary on prospects 3, 2016 for fundamental 1 / 32 physics without experiment Outline Some advertisements and some provocations: Advertisements: an old book, an ongoing blog, and a forthcoming book. Review what has happened to the idea of string theory unification. Raise the issue of what happens absent new experimental guidance. Can the example of mathematics help? Evidence for deep connections between math and physics: quantum mechanics and representation theory Speculation about relevance of ideas from representation theory to better understanding the Standard Model. Peter Woit (Columbia University) Not Even Wrong, ten years later: a view from mathematicsFebruary on prospects 3, 2016 for fundamental 2 / 32 physics without experiment An advertisment for three projects Not Even Wrong: the book Written largely in 2001-2 2003: under review at Cambridge University Press Fall 2004: accepted for publication by British publisher (with help from Roger Penrose) Mid-2006: published around same time as Lee Smolin's The Trouble with Physics. The \String Wars" kick off. Peter Woit (Columbia University) Not Even Wrong, ten years later: a view from mathematicsFebruary on prospects 3, 2016 for fundamental 3 / 32 physics without experiment An advertisment for three projects Not Even Wrong: the blog Started March 2004 In 2006, one of the battlefields of the string wars. Currently 1512 postings 41,335 comments Around 20,000 page-views/day (mostly robots...) http://www.math.columbia.edu/~woit/blog Peter Woit (Columbia University) Not Even Wrong, ten years later: a view from mathematicsFebruary on prospects 3, 2016 for fundamental 4 / 32 physics without experiment An advertisment for three projects An advertisement for the competition Finally in 2015, a book with the counter-argument I was expecting. -
Raiders of the Lost Spacetime
Raiders of the lost spacetime Christian W¨uthrich∗ For Dennis Lehmkuhl (ed.), Towards a Theory of Spacetime Theories. Birkh¨auser. Abstract Spacetime as we know and love it is lost in most approaches to quantum gravity. For many of these approaches, as inchoate and incomplete as they may be, one of the main challenges is to relate what they take to be the fundamental non-spatiotemporal structure of the world back to the classical spacetime of GR. The present essay investigates how spacetime is lost and how it may be regained in one major approach to quantum gravity, loop quantum gravity. Keywords: quantum gravity, problem of time, quantum GR, loop quantum gravity, emergence of spacetime. Many approaches to quantum gravity (QG) suggest or imply that space and time do not exist at the most fundamental ontological level, at least not in anything like their usual form. Thus deprived of their former status as part of the fundamental furniture of the world, together, perhaps, with quarks and leptons, they merely `emerge' from the deeper physics that does not rely on, or even permit, their (fundamental) existence, rather like tables and chairs. The extent to which the fundamental structures described by competing approaches to QG diverge from relativistic spacetimes varies, along different dimensions (Huggett and W¨uthrich 2012). That modern physics puts time under pressure is widely accepted. One can read the history of modern physics from the advent of relativity theory to the present day as a continuing peeling away of the structure that time was initially believed to exemplify (Huggett et al. -
Questions in Quantum Physics: a Personal View
Questions in quantum physics: a personal view Rudolf Haag Waldschmidtstraße 4b, D–83727 Schliersee-Neuhaus, Germany Abstract An assessment of the present status of the theory, some immediate tasks which are suggested thereby and some questions whose answers may require a longer breath since they relate to significant changes in the conceptual and mathematical structure of the theory. 1 Introduction Personal views are shaped by past experiences and so it may be worth while pondering a little about accidental circumstances which channelled the course of one’s own thinking. Meeting the right person at the right time, stumbling across a book or article which suddenly opens a new window. Fifty years ago, as eager students at Munich University just entering the phase of our own scientific research, we were studying the enormous papers by Julian Schwinger on Quantum Electrodynamics, following the arguments line by line but not really grasping the message. I remember the feelings of frustration, realizing that we were far away from the centers of action. But, mixed with this, also some dismay which did not only refer to the enormous arsenal of formalism in the new arXiv:hep-th/0001006v1 3 Jan 2000 developments of QED but began with the standard presentation of the interpretation of Quantum Theory. I remember long discussions with my thesis advisor Fritz Bopp, often while circling some blocks of streets ten times late in the evening, where we looked in vain for some reality behind the enigma of wave-particle dualism. Why should physical quantities correspond to operators in Hilbert space? Why should probabilities be described as absolute squares of amplitudes?, etc., etc. -
Detailing Coherent, Minimum Uncertainty States of Gravitons, As
Journal of Modern Physics, 2011, 2, 730-751 doi:10.4236/jmp.2011.27086 Published Online July 2011 (http://www.SciRP.org/journal/jmp) Detailing Coherent, Minimum Uncertainty States of Gravitons, as Semi Classical Components of Gravity Waves, and How Squeezed States Affect Upper Limits to Graviton Mass Andrew Beckwith1 Department of Physics, Chongqing University, Chongqing, China E-mail: [email protected] Received April 12, 2011; revised June 1, 2011; accepted June 13, 2011 Abstract We present what is relevant to squeezed states of initial space time and how that affects both the composition of relic GW, and also gravitons. A side issue to consider is if gravitons can be configured as semi classical “particles”, which is akin to the Pilot model of Quantum Mechanics as embedded in a larger non linear “de- terministic” background. Keywords: Squeezed State, Graviton, GW, Pilot Model 1. Introduction condensed matter application. The string theory metho- dology is merely extending much the same thinking up to Gravitons may be de composed via an instanton-anti higher than four dimensional situations. instanton structure. i.e. that the structure of SO(4) gauge 1) Modeling of entropy, generally, as kink-anti-kinks theory is initially broken due to the introduction of pairs with N the number of the kink-anti-kink pairs. vacuum energy [1], so after a second-order phase tran- This number, N is, initially in tandem with entropy sition, the instanton-anti-instanton structure of relic production, as will be explained later, gravitons is reconstituted. This will be crucial to link 2) The tie in with entropy and gravitons is this: the two graviton production with entropy, provided we have structures are related to each other in terms of kinks and sufficiently HFGW at the origin of the big bang. -
From Algebraic Quantum Field Theory to Effective Quantum Gravity
Algebraic approach to QFT Quantum gravity Locality and beyond: from algebraic quantum field theory to effective quantum gravity Kasia Rejzner University of York Local Quantum Physics and beyond in memoriam Rudolf Haag, 26.09.2016 Kasia Rejzner Locality and beyond 1 / 26 Algebraic approach to QFT Quantum gravity Outline of the talk 1 Algebraic approach to QFT AQFT LCQFT pAQFT 2 Quantum gravity Effective quantum gravity Observables The author of a beautiful book Local Quantum Physics. One of the fathers of LQP. We will all miss him. AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). Kasia Rejzner Locality and beyond 2 / 26 One of the fathers of LQP. We will all miss him. AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). The author of a beautiful book Local Quantum Physics. Kasia Rejzner Locality and beyond 2 / 26 We will all miss him. AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). The author of a beautiful book Local Quantum Physics. One of the fathers of LQP. Kasia Rejzner Locality and beyond 2 / 26 AQFT Algebraic approach to QFT LCQFT Quantum gravity pAQFT The father of Local Quantum Physics Rudolf Haag (1922 – 2016). The author of a beautiful book Local Quantum Physics. One of the fathers of LQP. We will all miss him. Kasia Rejzner Locality and beyond 2 / 26 It started as the axiomatic framework of Haag-Kastler[ Haag & Kastler 64]: a model is defined by associating to each region O of Minkowski spacetime the algebra A(O) of observables that can be measured in O. -
Oswald Veblen
NATIONAL ACADEMY OF SCIENCES O S W A L D V E B LEN 1880—1960 A Biographical Memoir by S A U N D E R S M A C L ANE Any opinions expressed in this memoir are those of the author(s) and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 1964 NATIONAL ACADEMY OF SCIENCES WASHINGTON D.C. OSWALD VEBLEN June 24,1880—August 10, i960 BY SAUNDERS MAC LANE SWALD VEBLEN, geometer and mathematical statesman, spanned O in his career the full range of twentieth-century Mathematics in the United States; his leadership in transmitting ideas and in de- veloping young men has had a substantial effect on the present mathematical scene. At the turn of the century he studied at Chi- cago, at the period when that University was first starting the doc- toral training of young Mathematicians in this country. He then continued at Princeton University, where his own work and that of his students played a leading role in the development of an outstand- ing department of Mathematics in Fine Hall. Later, when the In- stitute for Advanced Study was founded, Veblen became one of its first professors, and had a vital part in the development of this In- stitute as a world center for mathematical research. Veblen's background was Norwegian. His grandfather, Thomas Anderson Veblen, (1818-1906) came from Odegaard, Homan Con- gregation, Vester Slidre Parish, Valdris. After work as a cabinet- maker and as a Norwegian soldier, he was anxious to come to the United States. -
Luther Pfahler Eisenhart
NATIONAL ACADEMY OF SCIENCES L UTHER PFAHLER E ISENHART 1876—1965 A Biographical Memoir by S O L O M O N L EFSCHETZ Any opinions expressed in this memoir are those of the author(s) and do not necessarily reflect the views of the National Academy of Sciences. Biographical Memoir COPYRIGHT 1969 NATIONAL ACADEMY OF SCIENCES WASHINGTON D.C. LUTHER PFAHLER EISENHART January 13, 1876-October 28,1965 BY SOLOMON LEFSCHETZ UTHER PFAHLER EISENHART was born in York, Pennsylvania, L to an old York family. He entered Gettysburg College in 1892. In his mid-junior and senior years he was the only student in mathematics, so his professor replaced classroom work by individual study of books plus reports. He graduated in 1896 and taught one year in the preparatory school of the college. He entered the Johns Hopkins Graduate School in 1897 and ob- tained his doctorate in 1900. In the fall of the latter year he began his career at Princeton as instructor in mathematics, re- maining at Princeton up to his retirement in 1945. In 1905 he was appointed by Woodrow Wilson (no doubt on Dean Henry B. Fine's suggestion) as one of the distinguished preceptors with the rank of assistant professor. This was in accordance with the preceptorial plan which Wilson introduced to raise the educational tempo of Princeton. There followed a full pro- fessorship in 1909 and deanship of the Faculty in 1925, which was combined with the chairmanship of the Department of Math- ematics as successor to Dean Fine in January 1930. In 1933 Eisenhart took over the deanship of the Graduate School. -
Curriculum Vitae
Curriculum Vitae Assaf Naor Address: Princeton University Department of Mathematics Fine Hall 1005 Washington Road Princeton, NJ 08544-1000 USA Telephone number: +1 609-258-4198 Fax number: +1 609-258-1367 Electronic mail: [email protected] Web site: http://web.math.princeton.edu/~naor/ Personal Data: Date of Birth: May 7, 1975. Citizenship: USA, Israel, Czech Republic. Employment: • 2002{2004: Post-doctoral Researcher, Theory Group, Microsoft Research. • 2004{2007: Permanent Member, Theory Group, Microsoft Research. • 2005{2007: Affiliate Assistant Professor of Mathematics, University of Washington. • 2006{2009: Associate Professor of Mathematics, Courant Institute of Mathematical Sciences, New York University (on leave Fall 2006). • 2008{2015: Associated faculty member in computer science, Courant Institute of Mathematical Sciences, New York University (on leave in the academic year 2014{2015). • 2009{2015: Professor of Mathematics, Courant Institute of Mathematical Sciences, New York University (on leave in the academic year 2014{2015). • 2014{present: Professor of Mathematics, Princeton University. • 2014{present: Associated Faculty, The Program in Applied and Computational Mathematics (PACM), Princeton University. • 2016 Fall semester: Henry Burchard Fine Professor of Mathematics, Princeton University. • 2017{2018: Member, Institute for Advanced Study. • 2020 Spring semester: Henry Burchard Fine Professor of Mathematics, Princeton University. 1 Education: • 1993{1996: Studies for a B.Sc. degree in Mathematics at the Hebrew University in Jerusalem. Graduated Summa Cum Laude in 1996. • 1996{1998: Studies for an M.Sc. degree in Mathematics at the Hebrew University in Jerusalem. M.Sc. thesis: \Geometric Problems in Non-Linear Functional Analysis," prepared under the supervision of Joram Lindenstrauss. Graduated Summa Cum Laude in 1998. -
Foundations of Mathematics and Physics One Century After Hilbert: New Perspectives Edited by Joseph Kouneiher
FOUNDATIONS OF MATHEMATICS AND PHYSICS ONE CENTURY AFTER HILBERT: NEW PERSPECTIVES EDITED BY JOSEPH KOUNEIHER JOHN C. BAEZ The title of this book recalls Hilbert's attempts to provide foundations for mathe- matics and physics, and raises the question of how far we have come since then|and what we should do now. This is a good time to think about those questions. The foundations of mathematics are growing happily. Higher category the- ory and homotopy type theory are boldly expanding the scope of traditional set- theoretic foundations. The connection between logic and computation is growing ever deeper, and significant proofs are starting to be fully formalized using software. There is a lot of ferment, but there are clear payoffs in sight and a clear strategy to achieve them, so the mood is optimistic. This volume, however, focuses mainly on the foundations of physics. In recent decades fundamental physics has entered a winter of discontent. The great triumphs of the 20th century|general relativity and the Standard Model of particle physics| continue to fit almost all data from terrestrial experiments, except perhaps some anomalies here and there. On the other hand, nobody knows how to reconcile these theories, nor do we know if the Standard Model is mathematically consistent. Worse, these theories are insufficient to explain what we see in the heavens: for example, we need something new to account for the formation and structure of galaxies. But the problem is not that physics is unfinished: it has always been that way. The problem is that progress, extremely rapid during most of the 20th century, has greatly slowed since the 1970s. -
Particle Theory: a View from a Neighboring Field
Particle theory: a view from a neighboring field Peter Woit Mathematics Department Columbia University Rochester Physics and Astronomy Colloquium March 7, 2018 Peter Woit (Mathematics Department ColumbiaParticle University) theory: a view from a neighboring field March 7, 2018 1 / 31 Two cultures Physics 1979: B.A./M.A. in physics, Harvard 1984: Ph.D. in particle theory, Princeton 1984-87: Postdoc ITP Stony Brook Mathematics 1988: adjunct Calculus instructor, Tufts math department 1988-9: Postdoc, Mathematical Sciences Research Institute, Berkeley 1989-93: Asst. professor, Columbia math department (non-tenure track) 1993-current: Permanent non-tenured position at Columbia, now Senior Lecturer Neighboring fields, but very different language and culture. Remniscent of moving between US and France as a child (lived in Paris age 8-13). Peter Woit (Mathematics Department ColumbiaParticle University) theory: a view from a neighboring field March 7, 2018 2 / 31 The SM: a victim of its own success The Standard Model, some history 1973: SU(3) x SU(2) X U(1) gauge theory of strong, weak and electromagnetic forces 1983: Discovery of W/Z bosons 1995: Discovery of the top quark 1998: Discovery of non-zero neutrino masses (an extension of the original SM) 2012: Discovery of the Higgs at the LHC Current situation All high energy accelerator experiments consistent with the SM. Ongoing experiments at the LHC at 13 TeV center of mass energy. Peter Woit (Mathematics Department ColumbiaParticle University) theory: a view from a neighboring field March 7, 2018 -
August 9, 2001 Word Count: 7015 Words Abstract There Is A
PRESENTISM AND QUANTUM GRAVITY1 August 9, 2001 word count: 7015 words Abstract There is a philosophical tradition of arguing against presentism, the thesis that only presently existing things exist, on the basis of its incompatibility with fundamental physics. I grant that presentism is incompatible with special and general relativity, but argue that presentism is not incompatible with quantum gravity, because there are some theories of quantum gravity that utilize a fixed foliation of spacetime. I reply to various objections to this defense of presentism, and point out a flaw in Gödel’s modal argument for the ideality of time. This paper provides an interesting case study of the interplay between physics and philosophy. 1I have given talks based on previous versions of this paper at Princeton University, the American University of Beirut, California Polytechnic State University, and the University of Kentucky. I thank the audiences at these presentations for helpful discussion. I also thank Gordon Belot, Mauro Dorato, Brian Kierland, Steven Savitt, Bas van Fraassen, Steve Weinstein, and an anonymous referee for helpful comments. 1 1. Introduction. I am a presentist: I believe that only presently existing things exist.2 Contrast presentism with eternalism: the eternalist believes that past, present, and future things all exist. Assuming that there are three spatial dimensions, the eternalist believes that the universe is four- dimensional, and while there are different events in different regions of this so-called “block universe”, the universe as a whole does not change. The presentist, in contrast, believes that the universe is three-dimensional. I am also a Heraclitean: I believe that change is a fundamental aspect of reality. -
Samson Abramsky and Bob Coecke. an Integrated Diagrammatic Universe for Knowledge, Language and Artificial Reasoning. John
An integrated diagrammatic universe for knowledge, language and artificial reasoning Samson Abramsky and Bob Coecke October 5, 2015 Introduction In many different areas of scientific investigation, purely diagrammatic expressions have begun to be used as mathematical substitutes for the traditional symbolic expressions. These new languages reflect clear operational concepts such as ‘systems’ and ‘processes’, and ‘wires’ are used to represent information flow. Composition is built-in, as the act of connecting wires together. These diagrams are more intuitive, and easier to manipulate, than conventional symbolic models of reasoning. Examples of areas in which these techniques are being used include logic, for the study of propositions and deductions [43]; physics, for the study of space and spacetime [8, 32]; linguistics, to model the interaction of words within a sentence [21]; knowledge, to represent information and belief revision [22]; and computation, for the study of data and computer programs [1, 10]. These diagrams have been provided with a rigorous underpinning using category theory, a powerful branch of mathematics which relates these the diagrammatic theories to algebraic structures. More deeply, this approach can also be applied to the study of diagrammatic theories themselves [12, 33]. As such, it is its own ‘metatheory’. One major goal of the project will be to understand to what extent this can serve as a foundation for mathematics itself, as a replacement for set theory. To work towards this, one goal will be to understand how various mathematical structures can be defined from this perspective, a rich line of enquiry for which some answers are already known, but much more is left to still be discovered.