Proton Stability in Grand Unified Theories, in Strings, and in Branes
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Sab 2012 Mecbpn
Dos-Santos,W.A., et al. PROPOSTA DE UMA MISSÃO ESPACIAL PARA PICOSATÉLITES E ... PROPOSTA DE UMA MISSÃO ESPACIAL COMPLETA PARA PICOSATÉLITES E NANOSATÉLITES UTILIZANDO LANÇADORES NACIONAIS Walter Abrahão dos Santos, Fernanda Sayuri Yamasaki, Wilson Yamaguti Instituto Nacional de Pesquisas Espaciais – Av. dos Astronautas,1758 - CP515 - CEP 12227-010 São José dos Campos - SP, [email protected] , [email protected] , [email protected] Flávio de Azevedo Corrêa Jr. Instituto de Aeronáutica e Espaço – DCTA/IAE/SESP/PE, Praça Mal. Eduardo Gomes, 50 - Vila das Acácias, 12.228-904 - São José dos Campos - SP - Brasil - [email protected] Resumo: Devido ao mercado emergente de aplicações para pico e nanosatélites nas áreas de Espaço e Defesa, este trabalho se inspira na Missão Espacial Completa Brasileira (MECB), um programa conjunto de satélites e lançadores brasileiros, para propor um programa indutor de lançadores e plataformas voltados para satélites miniaturizados com missões sofisticadas devido a avanços em nanotecnologia e computação, entre outros. O trabalho considera dois grandes segmentos: (1) o segmento de lançadores focado na análise de viabilidade de veículos lançadores de pequenas cargas a uma altitude de aproximadamente 300 km e (2) o segmento relativo aos satélites objetivando embarcar cargas úteis com as seguintes aplicações em vista: um radiômetro, uma microcâmera e formação em voo. A análise foi basicamente concentrada nos envelopes de massa, tamanho, potência. A sustentabilidade do programa para estes satélites requer um acesso barato e regular ao espaço e é atrativa pela projeção futura deste nicho de mercado que pode contribuir com objetivos estratégicos do país. -
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. -
Small Satellite Launchers
SMALL SATELLITE LAUNCHERS NewSpace Index 2020/04/20 Current status and time from development start to the first successful or planned orbital launch NEWSPACE.IM Northrop Grumman Pegasus 1990 Scorpius Space Launch Demi-Sprite ? Makeyev OKB Shtil 1998 Interorbital Systems NEPTUNE N1 ? SpaceX Falcon 1e 2008 Interstellar Technologies Zero 2021 MT Aerospace MTA, WARR, Daneo ? Rocket Lab Electron 2017 Nammo North Star 2020 CTA VLM 2020 Acrux Montenegro ? Frontier Astronautics ? ? Earth to Sky ? 2021 Zero 2 Infinity Bloostar ? CASIC / ExPace Kuaizhou-1A (Fei Tian 1) 2017 SpaceLS Prometheus-1 ? MISHAAL Aerospace M-OV ? CONAE Tronador II 2020 TLON Space Aventura I ? Rocketcrafters Intrepid-1 2020 ARCA Space Haas 2CA ? Aerojet Rocketdyne SPARK / Super Strypi 2015 Generation Orbit GoLauncher 2 ? PLD Space Miura 5 (Arion 2) 2021 Swiss Space Systems SOAR 2018 Heliaq ALV-2 ? Gilmour Space Eris-S 2021 Roketsan UFS 2023 Independence-X DNLV 2021 Beyond Earth ? ? Bagaveev Corporation Bagaveev ? Open Space Orbital Neutrino I ? LIA Aerospace Procyon 2026 JAXA SS-520-4 2017 Swedish Space Corporation Rainbow 2021 SpinLaunch ? 2022 Pipeline2Space ? ? Perigee Blue Whale 2020 Link Space New Line 1 2021 Lin Industrial Taymyr-1A ? Leaf Space Primo ? Firefly 2020 Exos Aerospace Jaguar ? Cubecab Cab-3A 2022 Celestia Aerospace Space Arrow CM ? bluShift Aerospace Red Dwarf 2022 Black Arrow Black Arrow 2 ? Tranquility Aerospace Devon Two ? Masterra Space MINSAT-2000 2021 LEO Launcher & Logistics ? ? ISRO SSLV (PSLV Light) 2020 Wagner Industries Konshu ? VSAT ? ? VALT -
Grand Unification and Proton Decay
Grand Unification and Proton Decay Borut Bajc J. Stefan Institute, 1000 Ljubljana, Slovenia 0 Reminder This is written for a series of 4 lectures at ICTP Summer School 2011. The choice of topics and the references are biased. This is not a review on the sub- ject or a correct historical overview. The quotations I mention are incomplete and chosen merely for further reading. There are some good books and reviews on the market. Among others I would mention [1, 2, 3, 4]. 1 Introduction to grand unification Let us first remember some of the shortcomings of the SM: • too many gauge couplings The (MS)SM has 3 gauge interactions described by the corresponding carriers a i Gµ (a = 1 ::: 8) ;Wµ (i = 1 ::: 3) ;Bµ (1) • too many representations It has 5 different matter representations (with a total of 15 Weyl fermions) for each generation Q ; L ; uc ; dc ; ec (2) • too many different Yukawa couplings It has also three types of Ng × Ng (Ng is the number of generations, at the moment believed to be 3) Yukawa matrices 1 c c ∗ c ∗ LY = u YU QH + d YDQH + e YELH + h:c: (3) This notation is highly symbolic. It means actually cT αa b cT αa ∗ cT a ∗ uαkiσ2 (YU )kl Ql abH +dαkiσ2 (YD)kl Ql Ha +ek iσ2 (YE)kl Ll Ha (4) where we denoted by a; b = 1; 2 the SU(2)L indices, by α; β = 1 ::: 3 the SU(3)C indices, by k; l = 1;:::Ng the generation indices, and where iσ2 provides Lorentz invariants between two spinors. -
$\Delta L= 3$ Processes: Proton Decay And
IFIC/18-03 ∆L = 3 processes: Proton decay and LHC Renato M. Fonseca,1, ∗ Martin Hirsch,1, y and Rahul Srivastava1, z 1AHEP Group, Institut de F´ısica Corpuscular { C.S.I.C./Universitat de Val`encia,Parc Cient´ıficde Paterna. C/ Catedr´atico Jos´eBeltr´an,2 E-46980 Paterna (Valencia) - SPAIN We discuss lepton number violation in three units. From an effective field theory point of view, ∆L = 3 processes can only arise from dimension 9 or higher operators. These operators also violate baryon number, hence many of them will induce proton decay. Given the high dimensionality of these operators, in order to have a proton half-life in the observable range, the new physics associated to ∆L = 3 processes should be at a scale as low as 1 TeV. This opens up the possibility of searching for such processes not only in proton decay experiments but also at the LHC. In this work we analyze the relevant d = 9; 11; 13 operators which violate lepton number in three units. We then construct one simple concrete model with interesting low- and high-energy phenomenology. I. INTRODUCTION could be related to some particular combinations of lep- ton/quark flavours, as argued for example in [8], or to The standard model conserves baryon (B) and lepton total lepton and baryon numbers. The possibility we dis- (L) number perturbatively. However, this is no longer cuss in this paper is that lepton number might actually true for non-renormalizable operators [1] which might be be violated only in units of three: ∆L = 3. -
Redalyc.Status and Trends of Smallsats and Their Launch Vehicles
Journal of Aerospace Technology and Management ISSN: 1984-9648 [email protected] Instituto de Aeronáutica e Espaço Brasil Wekerle, Timo; Bezerra Pessoa Filho, José; Vergueiro Loures da Costa, Luís Eduardo; Gonzaga Trabasso, Luís Status and Trends of Smallsats and Their Launch Vehicles — An Up-to-date Review Journal of Aerospace Technology and Management, vol. 9, núm. 3, julio-septiembre, 2017, pp. 269-286 Instituto de Aeronáutica e Espaço São Paulo, Brasil Available in: http://www.redalyc.org/articulo.oa?id=309452133001 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative doi: 10.5028/jatm.v9i3.853 Status and Trends of Smallsats and Their Launch Vehicles — An Up-to-date Review Timo Wekerle1, José Bezerra Pessoa Filho2, Luís Eduardo Vergueiro Loures da Costa1, Luís Gonzaga Trabasso1 ABSTRACT: This paper presents an analysis of the scenario of small satellites and its correspondent launch vehicles. The INTRODUCTION miniaturization of electronics, together with reliability and performance increase as well as reduction of cost, have During the past 30 years, electronic devices have experienced allowed the use of commercials-off-the-shelf in the space industry, fostering the Smallsat use. An analysis of the enormous advancements in terms of performance, reliability and launched Smallsats during the last 20 years is accomplished lower prices. In the mid-80s, a USD 36 million supercomputer and the main factors for the Smallsat (r)evolution, outlined. -
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. -
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. -
Proton Decay at the Drip-Line Magic Number Z = 82, Corresponding to the Closure of a Major Nuclear Shell
NEWS AND VIEWS NUCLEAR PHYSICS-------------------------------- case since it has one proton more than the Proton decay at the drip-line magic number Z = 82, corresponding to the closure of a major nuclear shell. In Philip Woods fact the observed proton decay comes from an excited intruder state configura WHAT determines whether a nuclear ton decay half-life measurements can be tion formed by the promotion of a proton species exists? For nuclear scientists the used to explore nuclear shell structures in from below the Z=82 shell closure. This answer to this poser is that the species this twilight zone of nuclear existence. decay transition was used to provide should live long enough to be identified The proton drip-line sounds an inter unique information on the quantum mix and its properties studied. This still begs esting place to visit. So how do we get ing between normal and intruder state the fundamental scientific question of there? The answer is an old one: fusion. configurations in the daughter nucleus. what the ultimate boundaries to nuclear In this case, the fusion of heavy nuclei Following the serendipitous discovery existence are. Work by Davids et al. 1 at produces highly neutron-deficient com of nuclear proton decay4 from an excited Argonne National Laboratory in the pound nuclei, which rapidly de-excite by state in 1970, and the first example of United States has pinpointed the remotest boiling off particles and gamma-rays, leav ground-state proton decay5 in 1981, there border post to date, with the discovery of ing behind a plethora of highly unstable followed relative lulls in activity.