Supersymmetry
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Color Breaking in the Quantum Leaped Stop Decay
Color breaking in the quantum leaped stop decay Imre Czövek [email protected] Abstract. The superfield propagator contains a measurable quantum leap, which comes from the definition of SUSY. In the sfermion -> Goldstino + fermion vertex change: 1. the spin of sparticle with discrete 1/2, 2. the Grassman superspace with the Goldstino shift operator. 3. the spacetime as the result of extra dimensional leap. The leap nature of SUSY transformations appears in the squark decay, it is the analog definition of SUSY. The quantum leaped outgoing propagators are determined and break locally the energy and the charge. Like to the teleportation the entangled pairs are here the b quark and the Goldstino. The dominant stop production is from gluons. The stop-antistop pair decay to quantum leaped b (c or t) quark, and the decay break the color. I get for the (color breaking) quantum leap: 10^-18 m. 10^-11 m color breaking would be needed for a color breaking chain reaction. The open question is: Are the colliders producing supersymmetry charge? Because some charges in QGP can make long color breaking and a chain reaction. A long color broken QGP state in the re-Big Bang theory could explain the near infinite energy and the near infinite mass of the universe: - at first was random color QGP in the flat space-time, - at twice the color restoration in the curved space-time, which eats the Goldstinos, - and finally the baryon genesis. The re Big Bang make a supernova like collapse and a flat explosion of Universe. This explanation of SUSY hides the Goldstone fermion in the extra dimensions, the Goldstino propagate only in superspace and it is a not observable dark matter. -
Abdus Salam United Nations Educational, Scientific and Cultural International XA0101583 Organization Centre
the 1(72001/34 abdus salam united nations educational, scientific and cultural international XA0101583 organization centre international atomic energy agency for theoretical physics NEW DIMENSIONS NEW HOPES Utpal Sarkar Available at: http://www.ictp.trieste.it/-pub-off IC/2001/34 United Nations Educational Scientific and Cultural Organization and International Atomic Energy Agency THE ABDUS SALAM INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS NEW DIMENSIONS NEW HOPES Utpal Sarkar1 Physics Department, Visva Bharati University, Santiniketan 731235, India and The Abdus Salam Insternational Centre for Theoretical Physics, Trieste, Italy. Abstract We live in a four dimensional world. But the idea of unification of fundamental interactions lead us to higher dimensional theories. Recently a new theory with extra dimensions has emerged, where only gravity propagates in the extra dimension and all other interactions are confined in only four dimensions. This theory gives us many new hopes. In earlier theories unification of strong, weak and the electromagnetic forces was possible at around 1016 GeV in a grand unified theory (GUT) and it could get unified with gravity at around the Planck scale of 1019 GeV. With this new idea it is possible to bring down all unification scales within the reach of the next generation accelerators, i.e., around 104 GeV. MIRAMARE - TRIESTE May 2001 1 Regular Associate of the Abdus Salam ICTP. E-mail: [email protected] 1 Introduction In particle physics we try to find out what are the fundamental particles and how they interact. This is motivated from the belief that there must be some fundamental law that governs ev- erything. -
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 . -
Physics Beyond the Standard Model (BSM)
Vorlesung 10: Search for Physics Beyond the Standard Model (BSM) • Standard Model : success and problems • Grand Unified Theories (GUT) • Supersymmetrie (SUSY) – theory – direct searches • other models / ideas for physics BSM Tevatron and LHC WS17/18 TUM S.Bethke, F. Simon V10: BSM 1 The Standard Model of particle physics... • fundamental fermions: 3 pairs of quarks plus 3 pairs of leptons • fundamental interactions: through gauge fields, manifested in – W±, Z0 and γ (electroweak: SU(2)xU(1)), – gluons (g) (strong: SU(3)) … successfully describes all experiments and observations! … however ... the standard model is unsatisfactory: • it has conceptual problems • it is incomplete ( ∃ indications for BSM physics) Tevatron and LHC WS17/18 TUM S.Bethke, F. Simon V10: BSM 2 Conceptual Problems of the Standard Model: • too many free parameters (~18 masses, couplings, mixing angles) • no unification of elektroweak and strong interaction –> GUT ; E~1016 GeV • quantum gravity not included –> TOE ; E~1019 GeV • family replication (why are there 3 families of fundamental leptons?) • hierarchy problem: need for precise cancellation of –> SUSY ; E~103 GeV radiation corrections • why only 1/3-fractional electric quark charges? –> GUT indications for New Physics BSM: • Dark Matter (n.b.: known from astrophysical and “gravitational” effects) • Dark Energy / Cosmological Constant / Vacuum Energy (n.b.: see above) • neutrinos masses • matter / antimatter asymmetry Tevatron and LHC WS17/18 TUM S.Bethke, F. Simon V10: BSM 3 Grand Unified Theory (GUT): • simplest symmetry which contains U(1), SU(2) und SU(3): SU(5) (Georgi, Glashow 1974) • multiplets of (known) leptons and quarks which can transform between each other by exchange of heavy “leptoquark” bosons, X und Y, with -1/3 und -4/3 charges, ± 0 as well as through W , Z und γ. -
The Grand Unified Theory of the Firm and Corporate Strategy: Measures to Build Corporate Competitiveness
THE GRAND UNIFIED THEORY OF THE FIRM AND CORPORATE STRATEGY: MEASURES TO BUILD CORPORATE COMPETITIVENESS by Hong Y. Park Professor of Economics Department of Economics College of Business and Management Saginaw Valley State University University Center, MI 48710 e-mail: [email protected] Geon-Cheol Shin Professor School of Business Kyung Hee University Seoul, Korea e-mail: [email protected] This study was funded by the Fulbright Foundation, the Korea Economic Research Institute (KERI), and Saginaw Valley State University. Abstract A good understanding of the nature of the firm is essential in developing corporate strategies, building corporate competitiveness, and establishing sound economic policy. Several theories have emerged on the nature of the firm: the neoclassical theory of the firm, the principal agency theory, the transaction cost theory, the property rights theory, the resource-based theory and the evolutionary theory. Each of these theories identify some elements that describe the nature of the firm, but no single theory is comprehensive enough to include all elements of the nature of the firm. Economists began to seek a theory capable of describing the nature of the firm within a single, all- encompassing, coherent framework. We propose a unified theory of the firm, which encompasses all elements of the firm. We then evaluate performances of Korean firms from the unified theory of the firm perspective. Empirical evidences are promising in support of the unified theory of the firm. Introduction A good understanding of the nature of the firm is essential in developing corporate strategies and building corporate competitiveness. Several theories have emerged on the nature of the firm: The neoclassical theory of the firm, the principal agency theory, the transaction cost theory, the property rights theory, the resource-based theory and the evolutionary theory. -
String Phenomenology 1 Minimal Supersymmetric Standard Model
Swedish String/Supergravity Course 2008 String Phenomenology Marcus Berg 1 Minimal Supersymmetric Standard Model A good reference is Martin [2], a review that was first posted on hep-ph in 1997 but which has been updated three times, most recently in 2006. The MSSM consists of a number of chiral and vector supermultiplets, one for each existing quark or 1 lepton or gauge boson Aµ in the Standard Model (SM): spin: 0 1/2 1 N = 1 chiral supermultiplet φ N = 1 vector supermultiplet λ Aµ The new fields, the superpartners of and Aµ, are denoted by tildes and called "s-" for the new scalars, ~, and "-ino" for the new fermions, A~: 0 1/2 1 squarks, sleptons −! ~ − quarks, leptons gauginos−! A~ Aµ − gauge bosons This is just the generic notation; usually one is more specific. So for example, one N = 1 chiral mul- tiplet has the t quark as the fermionic field, and the scalar superpartner is the "stop", t~. We impose that the superpartner masses are around the TeV scale, or even a little lower. The scale of superpartner masses is not \derived" in any real sense2 in the MSSM, but from the point of view of particle phenomenology, an MSSM-like theory with only very heavy superpartners would be indistinguishable from the nonsuper- symmetric standard model at any experiments done in the foreseeable future, so why bother? In fact, even string theorists should have some favored scenario what will happen at near-future experiments and observations, so let's try to understand where people who do experiments for a living have put their money. -
![Arxiv:1711.04534V4 [Hep-Ph]](https://docslib.b-cdn.net/cover/1539/arxiv-1711-04534v4-hep-ph-1091539.webp)
Arxiv:1711.04534V4 [Hep-Ph]
UCI-HEP-TR-2017-15 Millicharged Scalar Fields, Massive Photons and the Breaking of SU(3)C U(1)EM × Jennifer Rittenhouse West∗ Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA and SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94309, USA (Dated: April 10, 2019) Under the assumption that the current epoch of the Universe is not special, i.e. is not the final state of a long history of processes in particle physics, the cosmological fate of SU(3)C × U(1)EM is investigated. Spontaneous symmetry breaking of U(1)EM at the temperature of the Universe today is carried out. The charged scalar field φEM which breaks the symmetry is found to be ruled out for the charge of the electron, q = e. − Scalar fields with millicharges are viable and limits on their masses and charges are found to be q . 10 3e and −5 mφEM . 10 eV. Furthermore, it is possible that U(1)EM has already been broken at temperatures higher −18 than T = 2.7K given the nonzero limits on the mass of the photon. A photon mass of mγ = 10 eV, the ∼ −13 current upper limit, is found to require a spontaneous symmetry breaking scalar mass of mφEM 10 eV with charge q = 10−6e, well within the allowed parameter space of the model. Finally, the cosmological fate of the strong interaction is studied. SU(3)C is tested for complementarity in which the confinement phase of QCD + colored scalars is equivalent to a spontaneously broken SU(3) gauge theory. -
A Study of Mesons and Glueballs
A Study of Mesons and Glueballs Tapashi Das Department of Physics Gauhati University This thesis is submitted to Gauhati University as requirement for the degree of Doctor of Philosophy Faculty of Science July 2017 Scanned by CamScanner Scanned by CamScanner Scanned by CamScanner Scanned by CamScanner Abstract The main work of the thesis is devoted to the study of heavy flavored mesons using a QCD potential model. Chapter 1 deals with the brief introduction of the theory of Quantum Chro- modynamics (QCD), potential models and the use of perturbation theory. In Chapter 2, the improved potential model is introduced and the solution of the non-relativistic Schro¨dinger’s equation for a Coulomb-plus-linear potential, V(r) = 4αs + br + c, Cornell potential has − 3r been conducted. The first-order wave functions are obtained using Dalgarno’s method. We explicitly consider two quantum mechanical aspects in our improved model: (a) the scale factor ‘c’ in the potential should not affect the wave function of the system even while applying the perturbation theory and (b) the choice of perturbative piece of the Hamiltonian (confinement or linear) should determine the effective radial separation between the quarks and antiquarks. Therefore for the validation of the quantum mechanical idea, the constant factor ‘c’ is considered to be zero and a cut-off rP is obtained from the theory. The model is then tested to calculate the masses, form factors, charge radii, RMS radii of mesons. In Chapter 3, the Isgur-Wise function and its derivatives of semileptonic decays of heavy-light mesons in both HQET limit (m ∞) and finite mass limit are calculated. -
Unified Equations of Boson and Fermion at High Energy and Some
Unified Equations of Boson and Fermion at High Energy and Some Unifications in Particle Physics Yi-Fang Chang Department of Physics, Yunnan University, Kunming, 650091, China (e-mail: [email protected]) Abstract: We suggest some possible approaches of the unified equations of boson and fermion, which correspond to the unified statistics at high energy. A. The spin terms of equations can be neglected. B. The mass terms of equations can be neglected. C. The known equations of formal unification change to the same. They can be combined each other. We derive the chaos solution of the nonlinear equation, in which the chaos point should be a unified scale. Moreover, various unifications in particle physics are discussed. It includes the unifications of interactions and the unified collision cross sections, which at high energy trend toward constant and rise as energy increases. Key words: particle, unification, equation, boson, fermion, high energy, collision, interaction PACS: 12.10.-g; 11.10.Lm; 12.90.+b; 12.10.Dm 1. Introduction Various unifications are all very important questions in particle physics. In 1930 Band discussed a new relativity unified field theory and wave mechanics [1,2]. Then Rojansky researched the possibility of a unified interpretation of electrons and protons [3]. By the extended Maxwell-Lorentz equations to five dimensions, Corben showed a simple unified field theory of gravitational and electromagnetic phenomena [4,5]. Hoffmann proposed the projective relativity, which is led to a formal unification of the gravitational and electromagnetic fields of the general relativity, and yields field equations unifying the gravitational and vector meson fields [6]. -
Supersymmetry Min Raj Lamsal Department of Physics, Prithvi Narayan Campus, Pokhara Min [email protected]
Supersymmetry Min Raj Lamsal Department of Physics, Prithvi Narayan Campus, Pokhara [email protected] Abstract : This article deals with the introduction of supersymmetry as the latest and most emerging burning issue for the explanation of nature including elementary particles as well as the universe. Supersymmetry is a conjectured symmetry of space and time. It has been a very popular idea among theoretical physicists. It is nearly an article of faith among elementary-particle physicists that the four fundamental physical forces in nature ultimately derive from a single force. For years scientists have tried to construct a Grand Unified Theory showing this basic unity. Physicists have already unified the electron-magnetic and weak forces in an 'electroweak' theory, and recent work has focused on trying to include the strong force. Gravity is much harder to handle, but work continues on that, as well. In the world of everyday experience, the strengths of the forces are very different, leading physicists to conclude that their convergence could occur only at very high energies, such as those existing in the earliest moments of the universe, just after the Big Bang. Keywords: standard model, grand unified theories, theory of everything, superpartner, higgs boson, neutrino oscillation. 1. INTRODUCTION unifies the weak and electromagnetic forces. The What is the world made of? What are the most basic idea is that the mass difference between photons fundamental constituents of matter? We still do not having zero mass and the weak bosons makes the have anything that could be a final answer, but we electromagnetic and weak interactions behave quite have come a long way. -
Super Symmetry
MILESTONES DOI: 10.1038/nphys868 M iles Tone 1 3 Super symmetry The way that spin is woven into the in 1015. However, a form of symmetry very fabric of the Universe is writ between fermions and bosons called large in the standard model of supersymmetry offers a much more particle physics. In this model, which elegant solution because the took shape in the 1970s and can quantum fluctuations caused by explain the results of all particle- bosons are naturally cancelled physics experiments to date, matter out by those caused by fermions and (and antimatter) is made of three vice versa. families of quarks and leptons, which Symmetry plays a central role in are all fermions, whereas the physics. The fact that the laws of electromagnetic, strong physics are, for instance, symmetric in and weak forces that act on these time (that is, they do not change with particles are carried by other time) leads to the conservation of particles, such as photons and gluons, energy. These laws are also symmetric The ATLAS experiment under construction at the which are all bosons. with respect to space, rotation and Large Hadron Collider. Image courtesy of CERN. Despite its success, the standard relative motion. Initially explored in model is unsatisfactory for a number the early 1970s, supersymmetry is a of reasons. First, although the less obvious kind of symmetry, which, graviton. Searching for electromagnetic and weak forces if it exists in nature, would mean that supersymmetric particles will be a have been unified into a single force, the laws of physics do not change priority when the Large Hadron a ‘grand unified theory’ that brings when bosons are replaced by Collider comes into operation at the strong interaction into the fold fermions, and fermions are replaced CERN, the European particle-physics remains elusive. -
Luminosity Determination and Searches for Supersymmetric Sleptons and Gauginos at the ATLAS Experiment Anders Floderus
Luminosity determination and searches for supersymmetric sleptons and gauginos at the ATLAS experiment Thesis submitted for the degree of Doctor of Philosophy by Anders Floderus CERN-THESIS-2014-241 30/01/2015 DEPARTMENT OF PHYSICS LUND, 2014 Abstract This thesis documents my work in the luminosity and supersymmetry groups of the ATLAS experiment at the Large Hadron Collider. The theory of supersymmetry and the concept of luminosity are introduced. The ATLAS experiment is described with special focus on a luminosity monitor called LUCID. A data- driven luminosity calibration method is presented and evaluated using the LUCID detector. This method allows the luminosity measurement to be calibrated for arbitrary inputs. A study of particle counting using LUCID is then presented. The charge deposited by particles passing through the detector is shown to be directly proportional to the luminosity. Finally, a search for sleptons and gauginos in final states −1 with exactly two oppositely charged leptons is presented. The search is based onp 20.3 fb of pp collision data recorded with the ATLAS detector in 2012 at a center-of-mass energy of s = 8 TeV. No significant excess over the Standard Model expectation is observed. Instead, limits are set on the slepton and gaugino masses. ii Populärvetenskaplig sammanfattning Partikelfysiken är studien av naturens minsta beståndsdelar — De så kallade elementarpartiklarna. All materia i universum består av elementarpartiklar. Den teori som beskriver vilka partiklar som finns och hur de uppför sig heter Standardmodellen. Teorin har historiskt sett varit mycket framgångsrik. Den har gång på gång förutspått existensen av nya partiklar innan de kunnat påvisas experimentellt, och klarar av att beskriva många experimentella resultat med imponerande precision.