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Arxiv:1903.02940V2
Proton decay and the quantum structure of spacetime 1, 1, 2,3, 4,5, Abeer Al-Modlej, ∗ Salwa Alsaleh, † Hassan Alshal, ‡ and Ahmed Farag Ali § 1 Department of Physics and Astronomy, King Saud University, Riyadh 11451, Saudi Arabia 2Department of Physics, University of Miami, Coral Gables, FL 33124, USA 3Department of Physics, Faculty of Science, Cairo University, Giza 12613, Egypt 4Department of Physics, Faculty of Science, Benha University, Benha, 13518, Egypt 5Quantum Gravity Research, Los Angeles, CA 90290, USA (Dated: October 29, 2019) Abstract Virtual black holes in noncommutative spacetime are investigated using coordinate coherent state formalism such that the event horizon of black hole is manipulated by smearing it with a Gaussian of width √θ, where θ is the noncommutativity parameter. Proton lifetime, the main associated phenomenology of the noncommutative virtual black holes, has been studied: first in 4 dimensional spacetime and then generalized to D dimensions. The lifetime depends on θ and the number of spacetime dimensions such that it emphasizes on the measurement of proton lifetime as a potential probe for the micro-structure of spacetime. Introduction promising to divulge many secrets about how nature works on quantum gravity level [22]. A black hole with 9 mass of Sun would have TBH 60 10− K at the event Since the introduction of Hawking radiation [1], horizon, while a black hole with∼ mass× of Earth’s moon geometrical many semiclassical, non-classical [2–9] and would have the surface temperature 2.7 K. So the ra- [10–12] endeavours—seeking “the” unified theory—have diation of astrophysical massive black∼ hole is too minute been striving to “shoehorn” general relativity into the to be detected in the Cosmic Microwave Background framework of quantum field theories (QFT). -
Out-Of-Equilibrium Transverse Momentum Spectra of Pions at LHC Energies
Hindawi Advances in High Energy Physics Volume 2019, Article ID 4604608, 7 pages https://doi.org/10.1155/2019/4604608 Research Article Out-Of-Equilibrium Transverse Momentum Spectra of Pions at LHC Energies Abdel Nasser Tawfik 1,2 1 Nile University, Egyptian Center for Teoretical Physics, Juhayna Square of 26th-July-Corridor, 12588 Giza, Egypt 2World Laboratory for Cosmology And Particle Physics (WLCAPP), 11571 Cairo, Egypt Correspondence should be addressed to Abdel Nasser Tawfk; [email protected] Received 9 March 2019; Revised 10 May 2019; Accepted 20 May 2019; Published 2 June 2019 Guest Editor: Sakina Fakhraddin Copyright © 2019 Abdel Nasser Tawfk. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In order to characterize the transverse momentum spectra (��) of positive pions measured in the ALICE experiment, two thermal approaches are utilized; one is based on degeneracy of nonperfect Bose-Einstein gas and the other imposes an ad hoc fnite pion chemical potential. Te inclusion of missing hadron states and the out-of-equilibrium contribute greatly to the excellent characterization of pion production. An excellent reproduction of these ��-spectra is achieved at �� =0.12GeV and this covers the entire range of ��. Te excellent agreement with the experimental results can be understood as a manifestation of not-yet- regarded anomalous pion production, which likely contributes to the long-standing debate on “anomalous” proton-to-pion ratios attopRHICandLHCenergies. 1. Introduction be well applied to low ��-regime (below a few GeV/c) [3]. -
4Th International Conference on New Frontiers in Physics, ICNFP2015, from 23 to 30 August 2015, Kolymbari, Crete, Greece
4th International Conference on New Frontiers in Physics, ICNFP2015, from 23 to 30 August 2015, Kolymbari, Crete, Greece From 23 to 24 August, Lectures From 24 to 30 August, Main Conference http://indico.cern.ch/e/icnfp2015 Yiota Foka on behalf of the ICNFP2015 Organizing Committee: Larissa Bravina, University of Oslo (Norway) (co-chair) Yiota Foka, GSI (Germany) (co-chair) Sonia Kabana, University of Nantes and Subatech (France) (co-chair) Evgeny Andronov, SPbSU (Russia) Panagiotis Charitos, CERN (Switzerland) Laszlo Csernai, University of Bergen (Norway) Nikos Kallithrakas, Technical University of Chania (Greece) Alisa Katanaeva, SPbSU (Russia) Elias Kiritsis, APC and University of Crete (Greece) Adam Kisiel, WUT (Poland) Vladimir Kovalenko, SPbSU (Russia) Emanuela Larentzakis, OAC, Kolymbari (Greece) Patricia Mage-Granados, CERN (Switzerland) Anton Makarov, SPbSU (Russia) Dmitrii Neverov, SPbSU (Russia) Ahmed Rebai, Completude Ac. Nantes (France) Andrey Seryakov, SPbSU (Russia) Daria Shukhobodskaia, SPbSU (Russia) Inna Shustina, (Ukraine) Abstract We apply for financial aid to support the participation of graduate students and postdoctoral research associates at the 4th International Conference on New Frontiers in Physics, to be held in Kolymbari, Crete, Greece, from 23 to 30 Au- gust 2015. The conference series \New Frontiers in Physics" aims to promote interdisciplinarity and cross-fertilization of ideas between different disciplines addressing fundamental physics. 1 Introduction While different fields each face a distinct set of field-specific challenges in the coming decade, a significant set of commonalities has emerged in the technical nature of some of these challenges, or are underlying the fundamental concepts involved. A Grand Unified Theory should in principle reveal this underlying relationship. -
Deconfinement and Freezeout Boundaries in Equilibrium Thermal Models
Hindawi Advances in High Energy Physics Volume 2020, Article ID 2453476, 8 pages https://doi.org/10.1155/2020/2453476 Research Article Deconfinement and Freezeout Boundaries in Equilibrium Thermal Models Abdel Nasser Tawfik ,1,2 Muhammad Maher,3 A. H. El-Kateb,3 and Sara Abdelaziz3 1Nile University, Egyptian Center for Theoretical Physics (ECTP), Juhayna Square of 26th-July-Corridor, 12588 Giza, Egypt 2Goethe University, Institute for Theoretical Physics (ITP), Max-von-Laue-Str. 1, D-60438 Frankfurt am Main, Germany 3Faculty of Science, Physics Department, Helwan University, 11795 Ain Helwan, Egypt Correspondence should be addressed to Abdel Nasser Tawfik; atawfi[email protected] Received 9 October 2019; Accepted 28 January 2020; Published 24 February 2020 Guest Editor: Jajati K. Nayak Copyright © 2020 Abdel Nasser Tawfik et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The publication of this article was funded by SCOAP3. In different approaches, the temperature-baryon density plane of QCD matter is studied for deconfinement and chemical freezeout boundaries. Results from various heavy-ion experiments are compared with the recent lattice simulations, the effective QCD-like Polyakov linear-sigma model, and the equilibrium thermal models. Along the entire freezeout boundary, there is an excellent agreement between the thermal model calculations and the experiments. Also, the thermal model calculations agree well with the estimations deduced from the Polyakov linear-sigma model (PLSM). At low baryonic density or high energies, both deconfinement and chemical freezeout boundaries are likely coincident, and therefore, the agreement with the lattice simulations becomes excellent as well, while at large baryonic density, the two boundaries become distinguishable forming a phase where hadrons and quark-gluon plasma likely coexist. -
Chiral Magnetic Properties of QCD Phase-Diagram
Eur. Phys. J. A (2021) 57:200 https://doi.org/10.1140/epja/s10050-021-00501-z Regular Article - Theoretical Physics Chiral magnetic properties of QCD phase-diagram Abdel Nasser Tawfik1,2 ,a , Abdel Magied Diab3 1 Present address: Institute for Theoretical Physics (ITP), Goethe University, Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany 2 Egyptian Center for Theoretical Physics (ECTP), Juhayna Square of 26th-July-Corridor, Giza 12588, Egypt 3 Faculty of Engineering, Modern University for Technology and Information (MTI), Cairo 11571, Egypt Received: 5 March 2021 / Accepted: 18 May 2021 / Published online: 21 June 2021 © The Author(s) 2021 Communicated by Carsten Urbach Abstract The QCD phase-diagram is studied, at finite mag- diagram could be drawn. The first prediction of end of the netic field. Our calculations are based on the QCD effective hadron domain, at high temperatures, was fomulated long model, the SU(3) Polyakov linear-sigma model (PLSM), in time before the invention of QCD, where the partons are which the chiral symmetry is integrated in the hadron phase assumed as the effective degrees-of-freedom (dof), at tem- and in the parton phase, the up-, down- and strange-quark peratures larger than the Hagedorn temperature TH [1,2]. degrees of freedom are incorporated besides the inclusion of The hadron matter forms fireballs of new particles, which Polyakov loop potentials in the pure gauge limit, which are can again produce new fireballs. In 1975, Cabibbo pro- motivated by various underlying QCD symmetries. The Lan- posed a QCD phase diagram in T − n B plane [3], where dau quantization and the magnetic catalysis are implemented. -
Quark-Hadron Phase Structure of QCD Matter from SU(4) Polyakov Linear Sigma Model
EPJ Web of Conferences 177, 09005 (2018) https://doi.org/10.1051/epjconf/201817709005 AYSS-2017 Quark-hadron phase structure of QCD matter from SU(4) Polyakov linear sigma model Abdel Magied Abdel Aal DIAB1,2,⋆ and Abdel Nasser TAWFIK 1,2,⋆⋆ 1Egyptian Center for Theoretical Physics (ECTP), MTI University, 11571 Cairo, Egypt. 2World Laboratory for Cosmology And Particle Physics (WLCAPP), Cairo, Egypt Abstract. The SU(4) Polyakov linear sigma model (PLSM) is extended towards charac- terizing the chiral condensates, σl, σs and σc of light, strange and charm quarks, respec- tively and the deconfinement order-parameters φ and φ¯ at finite temperatures and densi- ties (chemical potentials). The PLSM is considered to study the QCD equation of state in the presence of the chiral condensate of charm for different finite chemical potentials. The PLSM results are in a good agreement with the recent lattice QCD simulations. We conclude that, the charm condensate is likely not affected by the QCD phase-transition, where the corresponding critical temperature is greater than that of the light and strange quark condensates. 1 Introduction Quantum Chromodynamics (QCD) is a fundamental theory of the strong interaction acting upon quarks and gluons. Nowadays, the experimental and theoretical studies of charm physics turns to be a very active field in hadronic physics [1]. It was shown that the PLSM model, which is a QCD- like model, describes very successfully the phenomenology of the SU(3) quark-hadron structure in thermal and dense medium and also at finite magnetic field [2–10]. At low densities or as the temper- ature decreases, the quark gluon plasma (QGP), where the degrees of freedom of quark flavors, N f , are dominated, is conjectured to confine forming hadrons. -
Planck-Scale Corrections to Friedmann Equation
Cent. Eur. J. Phys. • 12(4) • 2014 • 245-255 DOI: 10.2478/s11534-014-0441-3 Central European Journal of Physics Planck-scale corrections to Friedmann equation Research Article Adel Awad∗1,2,3, Ahmed Farag Ali† 1,4 1 Centre for Fundamental Physics, Zewail City of Science and Technology Sheikh Zayed, 12588, Giza, Egypt 2 Department of Physics, Faculty of Science, Ain Shams University, Cairo, 11566, Egypt 3 Center for Theoretical Physics, British University of Egypt, Sherouk City 11837, P.O. Box 43, Egypt 4 Department of Physics, Faculty of Science, Benha University, Benha 13518, Egypt Received 16 November 2013; accepted 18 January 2014 Abstract: Recently, Verlinde proposed that gravity is an emergent phenomenon which originates from an entropic force. In this work, we extend Verlinde’s proposal to accommodate generalized uncertainty principles (GUP), which are suggested by some approaches to quantum gravity such as string theory, black hole physics and doubly special relativity (DSR). Using Verlinde’s proposal and two known models of GUPs, we obtain modifications to Newton’s law of gravitation as well as the Friedmann equation. Our modification to the Friedmann equation includes higher powers of the Hubble parameter which is used to obtain a cor- responding Raychaudhuri equation. Solving this equation, we obtain a leading Planck-scale correction to Friedmann-Robertson-Walker (FRW) solutions for the p = ωρ equation of state. PACS (2008): 04.60.Bc;04.60.Cf;04.70.Dy Keywords: quantum gravity • entropic force • thermodynamics • black holes © Versita sp. z o.o. 1. Introduction mutation relations between position coordinates and mo- menta [1–8]. -
Here Is a Direct Connection Between the Two Formalisms
TALK CONTRIBUTIONS Author: Francesco Becattini (University of Florence & FIAS Frankfurt) Title: Chemical equilibrium and chemical freeze-out Abstract: I will present a reanalysis of hadron production in relativistic nuclear collisions in view of recent measurements of proton and antiproton multiplicities at SPS and LHC. The low values of such multiplicities with respect to statistical model predictions can be accounted for by inelastic rescattering after hadronization. This phenomenon implies a correction to the concept of equilibrium chemical freeze-out. Using corrections from transport models, such as UrQMD, it is possible to reconstruct the primordial hadronization conditions, which occur at chemical equilibrium and nicely overlap with lattice QCD extrapolations at finite µB. NOTES: 1 Author: Sanjin Benić (University of Zagreb) Title: Hybrid stars from lattice constrained non-local PNJL model Abstract: Existing lattice data on the QCD phase diagram in the finite chemical potential region suggests that a strong vector channel interaction is present between quarks in the medium. This leads to a dramatic change of the cold quark Equation of State, in the sense that quark matter always appears as a state of lower pressure for a range of modern nuclear Equations of State. We will present some results of an ongoing study to reconcile this peculiar property in favor of quark matter at high densities, as is required by the property of asymptotic freedom. This will allow us to build hybrid Equations of State and test the model against new observations of heavy neutron stars. NOTES: 2 Author: Georg Bergner (ITP University Frankfurt) Title: Finite temperature analysis with effective Polyakov loop actions derived from a strong coupling expansion Abstract: Effective Polyakov loop models are a useful tool for an investigation of pure Yang-Mills theory and full QCD. -
Curriculum Vitae SAURYA DAS
Curriculum Vitae SAURYA DAS Personal details Date of birth: 30 June 1970 Nationalites: Canadian, Indian Languages: English, Bengali, Hindi (fluent), French (fair) Current position Professor of Physics, Department of Physics and Astronomy University of Lethbridge, Alberta, Canada Contact information Department of Physics and Astronomy, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta T1K 3M4, Canada E-mail: [email protected] Telephone: +1-403-329-2689 http://directory.uleth.ca/users/saurya.das http://scholar.ulethbridge.ca/sauryadas http://www.researchgate.net/profile/Saurya Das Other/previous positions • Affiliate Member, Perimeter Institute of Theoretical Physics, Waterloo, Canada. • Theme Leader, Quantum Foundations and Quantum Gravity, Quantum Alberta (Universities of Alberta, Calgary and Lethbridge). • 2008 - 2013: Associate Professor of Physics (tenured), University of Lethbridge, Alberta, Canada. Became a Full Professor in 2013. • 2003 - 2008: Assistant Professor of Physics, University of Lethbridge, Alberta, CANADA. • 2002 - 2003: Postdoctoral Fellow at University of New Brunswick, Fredericton, Canada. • 2000 - 2002: Postdoctoral Fellow at The University of Winnipeg & Winnipeg Institute for Theoretical Physics, Winnipeg, CANADA. • 1998 - 2000: Postdoctoral Fellow at The Center for Gravitational Physics and Geometry, The Pennsylvania State University, U.S.A. • 1994 - 1998: Research Fellow at The Institute of Mathematical Sciences, Chennai, India. Education and awards • Ph.D. in Theoretical Physics from The Institute of Mathematical Sciences, Chennai, India (1999). • First class in M.Sc. (by research) in Theoretical Physics from Anna University, Chennai, India (1994). • First class in B.Sc. (Physics Honours) from Presidency College, University of Calcutta, Kolkata, India (1992) - ranked second in the University. • Awards: Best Ph.D Thesis Award. Honorable Mention in the Gravity Research Foundation Essay Competitions - 2001, 2007, 2014, 2015, 2016. -
Curriculum Vitae SAURYA DAS
Curriculum Vitae SAURYA DAS Personal details Date of birth: 30 June 1970 Citizenship: Canadian Languages: English, Bengali, Hindi (fluent), French (functional) Current position Professor of Physics, Department of Physics and Astronomy University of Lethbridge, Alberta, Canada Contact information Department of Physics and Astronomy, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta T1K 3M4, Canada E-mail: [email protected] Telephone: +1-403-329-2689 http://directory.uleth.ca/users/saurya.das http://scholar.ulethbridge.ca/sauryadas http://www.researchgate.net/profile/Saurya Das Other/previous positions • Affiliate Member, Perimeter Institute of Theoretical Physics, Waterloo, Canada. • Theme Leader, Quantum Foundations and Quantum Gravity, Quantum Alberta (Universities of Alberta, Calgary and Lethbridge). • Full Professor of Physics University of Lethbridge, Alberta, Canada. • 2008 - 2013: Associate Professor of Physics (tenured), University of Lethbridge, Alberta, Canada. • 2003 - 2008: Assistant Professor of Physics, University of Lethbridge, Alberta, CANADA. • 2002 - 2003: Postdoctoral Fellow at University of New Brunswick, Fredericton, Canada. • 2000 - 2002: Postdoctoral Fellow at The University of Winnipeg & Winnipeg Institute for Theoretical Physics, Winnipeg, CANADA. • 1998 - 2000: Postdoctoral Fellow at The Center for Gravitational Physics and Geometry, The Pennsylvania State University, U.S.A. • 1994 - 1998: Research Fellow at The Institute of Mathematical Sciences, Chennai, India. Education and awards • Ph.D. in Theoretical Physics from The Institute of Mathematical Sciences, Chennai, India (1999). • First class in M.Sc. (by research) in Theoretical Physics from Anna University, Chennai, India (1994). • First class in B.Sc. (Physics Honours) from Presidency College, University of Calcutta, Kolkata, India (1992) - ranked second in the University. 1 • Awards: Best Ph.D Thesis Award. -
QCD-Like Approach (Lσm) for Heavy-Ion Collisions
QCD-like Approach (LM) for Heavy-Ion Collisions Abdel Nasser Tawfik Egyptian Center for Theoretical Physics (ECTP), World Laboratory for Cosmology And Particle Physics (WLCAPP) Modern University for Technology and Information (MTI Univ.) Cairo, September 25, 2014 http://atawfik.net/ Roots Sigma-Model is a Physical system with the Lagrangian The fields φi represent map from a base manifold called worldsheet (spacetime) to a target (Riemannian) manifold of the scalars linked together by internal symmetries. The scalars gij determines linear and non-linear properties. It was introduced by Gell-Mann and Levy in 1960. The name σ- model comes from a field in their model corresponding to a spinless meson σ, a scalar introduced earlier by Schwinger. Symmetries • Pisarski and Wilczek discussed the order of the chiral transition using renormalization group arguments in the framework of LM. • LM is the effective theory for the low-energy degrees of freedom of QCD and incorporates the global SU(Nf)r × SU(Nf)ℓ × U(1)A symmetry, but not the local SU(3)c color symmetry. • They found that, for Nf = 2 flavors of massless quarks, the transition can be of second order, if the U(1)A symmetry is explicitly broken by instantons. • It is driven first order by fluctuations, if the U(1)A symmetry is restored at Tc. • For Nf = 3 massless flavors, the transition is always first order. In this case, the term which breaks the U(1)A symmetry explicitly is a cubic invariant, and consequently drives the transition first order. • In the absence of explicit U(1)A symmetry breaking, the transition is fluctuation-induced of first order. -
Chapter 16.Pdf
CHAPTER SIXTEEN ENERGY PARTICLE-PHYSICS: THE EFFORTS OF ABDEL NASSER TAWFIK Musa Abdulwaheed, Ahmad F. Ismail Fac. ofEng., International Islamic Univ. Malaysia (HUM), Jalan Gombak, 53100 Kuala Lumpur, Malaysia. 16.1 INTRODUCTION Particle physics kas impacted the philosophy of science greatly. It is a branch of physics that studies the existence and interactions of particles that are the constituents of what is usually referred to as matter or radiation. Abdel Nasser Tawfik, Egyptian-born German particle physicist has made his mark in this field. He has the award ofWho's Who in Science and Engineering and aims at simplifying scientific issues for public and fmding nexus between science and religion. Dr. Tawfik has been providing seminars on various scientific issues. The objective of this chapter is to discuss his contribution to energy particle specifically in the area of Quantum Chromo-Dynamics (QCD). It is of note that the significance of this chapter is appreciating efforts of Islamic Thinkers and Scientists like Tawfik and his QCD phase diagram contribution to the field of energy particle physics. The method ofresearch adopted is based on library materials, internet sources and academic discussions. The theory and the research framework are limited to focusing mainly on reviewing the person of Abdel Nasser Tawfik, energy particle physics and the Tawfik's outstanding contribution. 16.2 THE WORLD OF ABDEL NASSER TAWFIK Born in Egypt on 22ndJune, 1967, Abdel Nasser Tawfik graduated from Assiut University in 1989. He obtained his Master Degree (M.Sc) in Theoretical Physics from the same University before his change to the University ofMarburg, Germany for his Ph.D.