Looking for the God Particle at the Large Hadron Collider Mary Beth De Repentigny
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Spontaneous Electroweak Symmetry Breaking
Arianna Borrelli Who broke electroweak symmetry? Who broke electroweak symmetry? This question may sound rather naive, yet the discourse about the “spontaneous” breaking of electroweak symmetry entails a reference to agency which finds implicit expression in the often repeated (and equally often criticized) statement that the particles of the Standard Model “acquire” their mass “thanks to” the Higgs boson. The implicit agency manifests itself in its most extreme form in the nickname happily bestowed on the Higgs boson in the popular press: “the God particle”. The construction of spontaneous symmetry breaking can be analysed as the interplay between different mathematical formalisms, phenomena of various nature and verbal statements connecting the whole and endowing it with physical meaning. One may argue that the latter, verbal component played a key role in the development of the notion of spontaneous symmetry breaking, spinning a narrative which allowed to close gaps in mathematical arguments and downplay the arbitrariness of analogies between phenomena. From this process emerged an ambiguous mathematical-physical notion which was to become the symbolic carrier of a “mechanism of mass generation”. In the papers quoted as the origin of spontaneous symmetry breaking Yoshiro Nambu and Giovanni Jona Lasinio used an analogy to super-conductive systems to interpret the masses of strongly interacting particles as expression of an exact, but hidden symmetry (N 1960, N/JL 1961). They did not speak of “symmetry breaking” - let alone a “spontaneous” one - but rather of the existence of “superconductor solutions” to the equations for particle self-energy. Jeffrey Goldstone (1961) reformulated their arguments in terms of an elementary scalar field with non-zero vacuum expectation value, but it was Marshall Baker and Sheldon Glashow (1962) who framed the issue as “spontaneous symmetry breaking”, attempting to explain mass values in terms of “stable self-generated solution” of quantum-field-theoretical equations. -
From Leon Lederman, the God Particle (Last Reading Continued)
18 From Leon Lederman, The God Particle (last reading continued) …. DEMOCRITUS: I have trouble with emptiness. How do I describe it? If it is truly nothing, then how can it exist? My hands touch your desk here. On the way to the desk top, my palm feels the gentle rush of air that fills the void between me and the desk's surface. Yet air cannot be the void itself, as Empedocles so ably pointed out. How can I imagine my atoms if I cannot feel the void in which they must move? And yet, if I want to somehow account for the world by atoms, I must first define something that seems to be undefinable because it is devoid of properties. LEDERMAN: So what did you do? DEMOCRITUS [laughing]: I decided not to worry. I a-voided the issue. LEDERMAN: Oi Vay! DEMOCRITUS: Sorry. Seriously, I solved the problem with my knife. LEDERMAN: Your imaginary knife that cuts cheese into atoms? DEMOCRITUS: No, a real knife, cutting, say, a real apple. The blade must find empty places where it can penetrate. LEDERMAN: What if the apple is composed of solid atoms, packed together with no space? DEMOCRITUS: Then it would be impenetrable, because atoms are impenetrable. No, all matter that we can see and feel is cuttable if you have a sharp enough blade. Therefore the void exists. But mostly I said to myself back then, and I believe it still, that one must not forever be stalled by logical impasses. We go on, we continue as if nothingness can be accepted. -
The Messenger
THE MESSENGER No. 35-March 1984 Report on the First ESO-CERN Symposium on "Large Scale Structure of the Universe, Cosmology and Fundamental Physics" G. Setti, ESO The first ESO-CERN Symposium was held at CERN, deuterium, were produced when the age of the Universe was Geneva, from 21 st to 25th November 1983 and was attended only about 100 seconds, the temperature about one billion by approximately 200 participants. The discussions concen degrees and the density of the order of the density of water, in trated on the general field of Cosmology, where the progress a phase that lasted about 8 minutes. At that moment the made in the past twenty years, both in elementary particles Universe was essentially a gaseous mixture composed of and astronomy, has shown that these two fields of basic protons, neutrons, electrons, positrons, neutrinos and anti research are merging toward a new and fundamental under neutrinos (and perhaps some other exotic particles, such as standing of the laws that govern our Universe. A detailed photinos) immersed in a heat bath of photons. The equilibrium account is contained in the Proceedings of the Symposium between these components is maintained by the weak which will be available in a few months. interaction, one of the four fundamental forces wh ich are The meeting was started with an introductory lecture by believed to govern all natural phenomena.* The weak force D. W. Sciama (Oxford and Trieste) who highlighted the numer together with the "hot big-bang" model allows definite predic ous and fundamental problems the understanding of which tions about the abundances of primordial elements. -
Furukawa's Technology Contributed to the Discovery of the Higgs Boson
Furukawa Here and There Special About the Furukawa’s technology Higgs boson contributed to the discovery It is an elementary particle, which is the smallest unit in nature. Modern of the Higgs boson physics considers that all phenomena n July 4, the discovery of the Higgs boson in the natural world can be explained called “God particle” received extensive in 17 elementary particles. Discovery of O century? coverage in the press. The European Council Sixteen of the 17 particles, including for Nuclear Research (Conseil Européen pour la What’s so great those that constitute substances about it? Recherche Nucléaire: CERN), headquartered in and those that transmit forces, had Geneva, Switzerland, announced the discovery of a already been discovered. Only the new particle that it deemed to be the Higgs boson, Higgs boson, which functions to which for many years has been the target of a search provide mass (weight) to substances, by physicists around the world. Furukawa Electric had remained unidentified. contributed significantly to what some are calling the discovery of the century. The Higgs boson is referred to as the “God particle” because it has a significant role in the formation of the universe and substances. This made it easier for The birth of the universe elementary particles with Speed mass to gather. Some of Elementary particle Elementary particle of I feel these particles stuck to one light! Higgs boson something another to form the origin of heavy atoms. This is how the Earth, all substances in the universe I see. and humankind are believed to have originated. It is said that if it were no Higgs boson, the human body would be torn apart in one billionth of a second. -
Extending Symmetries of the Standard Model Towards Grand Unification
Master research Extending Symmetries of the Standard Model towards Grand Unification Anno Touwen Supervisor prof. dr. Dani¨el Boer August 3, 2018 Abstract In this master thesis the spacetime, global and gauge symmetries of the Standard Model are reviewed. These symmetries are used as a basis for finding possible extensions of this successful model, such as the two Higgs doublet model and Left-Right model. Methods of finding subgroups and the slitting up of representations are discussed based on Dynkin diagrams. These methods are applied to analyse the subgroups of the exceptional group E6 as candidates for Grand Unified 3 Theory groups. In this study SU(5), SO(10) and SU(3) and SU(4)×SU(2)×SU(2) are most important. A phenomenological comparison between these models is given focussed on the different types of leptoquarks that could be responsible for the not yet observed proton decay. Contents 1 Introduction 3 2 Symmetry groups and Gauge theories 5 2.1 Group theory . .5 2.2 Unitary and Special Unitary groups . .8 2.3 Orthogonal and Special Orthogonal groups . 10 2.4 Gauge theories and fields . 11 2.5 Spacetime symmetries . 13 2.6 C, P and T transformations . 14 3 The Standard Model 16 3.1 The Electroweak interaction . 16 3.2 The Strong interaction . 19 3.3 Fermion content . 19 3.4 Eigenstates and the CKM-matrix . 22 3.5 Global symmetries . 23 4 Beyond the Standard Model 28 4.1 Two Higgs doublet model . 28 4.2 Left-Right models . 34 5 A further study of Lie Groups and Algebras 37 5.1 Root systems . -
In Search of the God Particle
Tomorrow - What Lies Beyond the Horizon The God Particle Weizmann Institute of Science by Eilam Gross In Search of the God Particle By Eilam Gross The extraordinary experiment being conducted in CERN (the European Organization for Nuclear Research), in Switzerland, aspires to bring us closer than ever to the moment of Creation – the Big Bang, when the elementary particles making up the Universe were created. Billions of dollars have been invested into this quest to find out where we come from and where we are going. About 14 billion years ago – 13.7 to be precise – the Universe was born. It emerged from a singular, energy-laden point in an event we know as the Big Bang. An updated Bible would begin with the verse: “In the beginning there was nothing. And God said: Let there be light. And there was a Big Bang, and there was space and there was time, and there was the space-time.” At the moment, no one knows what really happened during that initial infinitesimal fraction of a second of creation. We are quite certain though, that the immense energy of that moment gave rise to the conditions necessary for the creation of matter and forces, thus initiating a long process that eventually led to the existence of humans with the ability to apply our intelligence to deciphering the elements that are the building blocks of our own creation. In 1900, 108 years ago and almost 14 billion years after the Big Bang, a 76- year-old Lord William Thomson Kelvin stood in an auditorium filled to bursting in the British Royal Society and gave one of the most famous lectures in the history of physics. -
Anomaly and Cobordism Constraints Beyond the Standard Model
Anomaly and Cobordism Constraints Beyond the Standard Model: Topological Force Juven Wang Center of Mathematical Sciences and Applications, Harvard University, Cambridge, MA 02138, USA Abstract Standard lore uses perturbative local anomalies to check the kinematic consistency of gauge theories coupled to chiral fermions, such as the Standard Models (SM) of particle physics. In this work, based on a systematic cobordism classification, we examine the constraints from invertible quantum anomalies (including all perturbative local anomalies and all nonperturbative global anomalies) for SM and chiral gauge theories. We also clarify the different uses of these anomalies: including (1) anomaly cancellations of dynamical gauge fields, (2) ’t Hooft anomaly matching conditions of background fields of global symmetries. We apply several 4d anomaly constraints of Z16, Z4, and Z2 classes, beyond the familiar Feynman-graph perturbative Z class local anomalies. As an application, for SU(3)×SU(2)×U(1) Zq SM (with q = 1; 2; 3; 6) and SU(5) Grand Unification with 15n chiral Weyl fermions and with a discrete baryon minus lepton number X = 5(B L) 4Y preserved, we discover a new hidden gapped sector previously unknown to the SM and− Georgi-Glashow− model. The gapped sector at low energy contains either (1) 4d non-invertible topological quantum field theory (TQFT, above the energy gap with heavy fractionalized anyon excitations from 1d particle worldline and 2d string worldsheet, inaccessible directly from Dirac or Majorana mass gap of the 16th Weyl fermions [i.e., right-handed neutrinos], but accessible via a topological quantum phase transition), or (2) 5d invertible TQFT in extra dimensions. -
Books 15-6Mx
book reviews very existence of the observable Universe to understand if it were not universally depends upon the spontaneous manifesta- chiral. tion of asymmetry, the phenomenon physi- I personally think it a great pity that Close cists call ‘broken symmetry’. Close focuses, at did not tell the story of broken symmetry as it first, on two discrete broken symmetries: the really happened, because it is a heartening universal ‘handedness’ of life — its left–right story of one of those rare periods when the asymmetry — and the cosmic preference for fragmentation of theoretical physics into matter over antimatter. In the final chapters, condensed-matter, nuclear and particle he goes on to expound the broken continu- branches was temporarily healed and we ous symmetry that is behind the unification were all consciously working together in of weak and electromagnetic interactions. exploring the many quantum consequences It is hard to judge how accessible the lay- of the idea of broken symmetry. man will find tutorial explication of the sort These consequences are as far-reaching contained in this book. For instance, it’s not and as intellectually stimulating in con- clear to me why Stephen Hawking’s writing densed matter as in particle physics, and in seems to be comprehensible, or at least not discussing them Close reveals a definite acceptable, to the layman; I would judge bias in favour of the ‘clean machines’ of par- Close to be much more accessible. So, to my ticle physics as opposed to the mundane limited sense of these things, this should be a complications of condensed matter. -
The God Particle: If the Universe Is the Answer, What Is the Question?
[PDF] The God Particle: If The Universe Is The Answer, What Is The Question? Dick Teresi, Leon Lederman - pdf download free book The God Particle: If The Universe Is The Answer, What Is The Question? PDF Download, The God Particle: If The Universe Is The Answer, What Is The Question? Download PDF, Read Best Book Online The God Particle: If The Universe Is The Answer, What Is The Question?, The God Particle: If The Universe Is The Answer, What Is The Question? Free Read Online, full book The God Particle: If The Universe Is The Answer, What Is The Question?, free online The God Particle: If The Universe Is The Answer, What Is The Question?, Download PDF The God Particle: If The Universe Is The Answer, What Is The Question?, pdf free download The God Particle: If The Universe Is The Answer, What Is The Question?, the book The God Particle: If The Universe Is The Answer, What Is The Question?, Read Best Book Online The God Particle: If The Universe Is The Answer, What Is The Question?, Read Online The God Particle: If The Universe Is The Answer, What Is The Question? E-Books, Read The God Particle: If The Universe Is The Answer, What Is The Question? Online Free, Read The God Particle: If The Universe Is The Answer, What Is The Question? Full Collection, The God Particle: If The Universe Is The Answer, What Is The Question? PDF read online, The God Particle: If The Universe Is The Answer, What Is The Question? pdf read online, The God Particle: If The Universe Is The Answer, What Is The Question? PDF Download, The God Particle: If The Universe -
What Is a Higgs Boson?
Fermi National Accelerator Laboratory August 2015 What is a Higgs boson? In 2012 at the Large Hadron Collider, scientists discovered the long-sought Higgs boson. Now the question is: Are there more types of Higgs bosons? The Higgs field provides mass to quarks and other elementary particles that are the building blocks of matter. The photon and the gluon do not interact with the Higgs field, and hence they have no mass. Whether the Higgs field is the origin of the mass of dark matter or the tiny mass of the three known types of neutrinos is not yet known. What is a Higgs field? What is a Higgs boson? When did scientists discover the Higgs boson? The Higgs field is a force field that acts like a giant vat of molasses Scientists searched for the Higgs boson for more than two decades, spread throughout the universe. Most of the known types of particles starting with the LEP experiments at CERN in the 1990s and the that travel through it stick to the molasses, which slows them down Tevatron experiments at Fermilab in the 2000s. Years’ worth of LEP and makes them heavier. The Higgs boson is a particle that helps and Tevatron data narrowed the search for the Higgs particle. Then, transmit the mass-giving Higgs field, similar to the way a particle of in 2012 at CERN’s Large Hadron Collider (LHC), two experiments, light, the photon, transmits the electromagnetic field. ATLAS and CMS, reported the observation of a Higgs-like particle. With further analysis the new particle was confirmed as the Higgs boson in 2013. -
Particle Physics After the Higgs-Boson Discovery: Opportunities for the Large Hadron Collider
Particle Physics after the Higgs-Boson Discovery: Opportunities for the Large Hadron Collider Chris Quigg∗ Theoretical Physics Department, Fermi National Accelerator Laboratory P.O. Box 500, Batavia, Illinois 60510 USA Institut de Physique Th´eoriquePhilippe Meyer Laboratoire de Physique Th´eoriquede l'Ecole´ Normale Sup´erieure 24 rue Lhomond, 75231 Paris Cedex 05, France (Revised August 14, 2015 ) The first run of the Large Hadron Collider at CERN brought the discovery of the Higgs boson, an apparently elementary scalar particle with a mass of 125 GeV, the avatar of the mechanism that hides the electroweak symmetry. A new round of experimentation is beginning, with the energy of the proton{proton colliding beams raised to 6:5 TeV per beam, from 4 TeV at the end of the first run. This article summarizes what we have learned about the Higgs boson, and calls attention to some issues that will be among our central concerns in the near future. Keywords: Electroweak symmetry breaking, Higgs boson, Large Hadron Collider, New particles and interactions 1 Introduction In a previous contribution [1], written before experiments began at the Large Hadron Collider, I laid out the essential elements of the electroweak theory and prospects for the first wave of experimental studies at energies around 1 TeV for collisions among quarks and gluons.1 In that regime, we could confidently expect to learn about the mechanism that hides the gauge symmetry on which the electroweak theory is founded. Although the LHC operated at less than 60% of its 7 7 TeV design energy, experiments in 2011{2012 took the first giant step toward understanding electroweak⊕ symmetry breaking, discovering the Higgs boson and beginning to catalogue its properties. -
Read Frequently Asked Questions About the Higgs Boson
Frequently Asked Questions About the Higgs Boson What is a Higgs field? What is a Higgs boson? The Higgs field is like a giant vat of molasses spread throughout the universe. Most of the known types of particles that travel through it stick to the molasses, which slows them down and makes them heavier. The Higgs boson is a particle that helps transmit the mass-giving Higgs force field, similar to the way a particle of light, the photon, transmits the electromagnetic field. How long have physicists been looking for the Higgs boson? More than two decades. It started with the LEP experiments at CERN in the 1990s, continued with the Tevatron experiments at Fermilab and now continues with the Large Hadron Collider (LHC) experiments at CERN. A discovery of the Higgs boson would be just the beginning of a new era of particle physics research. Scientists would then focus on understanding in detail the interactions of the Higgs boson with other particles, testing the predictions made by theorists and looking for unexpected phenomena. What would the world look like without the Higgs boson or a similar particle? You wouldn’t recognize the world. Without the Higgs boson or something like it giving mass to the basic building blocks of matter, electrons would zip about at the speed of light. They would not form unions with protons or other would-be nuclei to make atoms. No atoms means no chemical reactions, no molecules, no ordinary matter as we know it, no template for life. We would not exist. How do physicists create a Higgs boson? A high-energy particle accelerator such as the Tevatron or LHC can recreate the extreme energies of the very early universe, generated shortly after the Big Bang.