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Implications of Gravitational Particle Creation Advances in High Energy Physics Implications of Gravitational Particle Creation Lead Guest Editor: Subhajit Saha Guest Editors: Kazuharu Bamba and Martiros Khurshudyan Implications of Gravitational Particle Creation Advances in High Energy Physics Implications of Gravitational Particle Creation Lead Guest Editor: Subhajit Saha Guest Editors: Kazuharu Bamba and Martiros Khurshudyan Copyright © 2019 Hindawi. All rights reserved. This is a special issue published in “Advances in High Energy Physics.” All articles are open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Editorial Board Antonio J. Accioly, Brazil Chao-Qiang Geng, Taiwan Anastasios Petkou, Greece Giovanni Amelino-Camelia, Italy Philippe Gras, France Alexey A. Petrov, USA Luis A. Anchordoqui, USA Xiaochun He, USA Thomas Rössler, Sweden Michele Arzano, Italy Luis Herrera, Spain Diego Saez-Chillon Gomez, Spain T. Asselmeyer-Maluga, Germany Filipe R. Joaquim, Portugal Takao Sakaguchi, USA Alessandro Baldini, Italy Aurelio Juste, Spain Juan José Sanz-Cillero, Spain Marco Battaglia, Switzerland Theocharis Kosmas, Greece Edward Sarkisyan-Grinbaum, USA Lorenzo Bianchini, Switzerland Ming Liu, USA Sally Seidel, USA Roelof Bijker, Mexico Enrico Lunghi, USA George Siopsis, USA Burak Bilki, USA Salvatore Mignemi, Italy Luca Stanco, Italy Rong-Gen Cai, China Omar G. Miranda, Mexico Jouni Suhonen, Finland Anna Cimmino, France Grégory Moreau, France Mariam Tórtola, Spain Osvaldo Civitarese, Argentina Piero Nicolini, Germany Smarajit Triambak, South Africa Andrea Coccaro, Italy Carlos Pajares, Spain Jose M. Udías, Spain Shi-Hai Dong, Mexico Sergio Palomares-Ruiz, Spain Elias C. Vagenas, Kuwait Mariana Frank, Canada Giovanni Pauletta, Italy Sunny Vagnozzi, UK Ricardo G. Felipe, Portugal Yvonne Peters, UK YauW.Wah,USA Contents Implications of Gravitational Particle Creation Subhajit Saha , Kazuharu Bamba, and Martiros Khurshudyan Editorial (2 pages), Article ID 1307167,Volume 2019 (2019) Particle Production via Dirac Dipole Moments in the Magnetized and Nonmagnetized Exponentially Expanding Universe Semra Gurtas Dogan, Ganim Gecim, and Yusuf Sucu Research Article (7 pages), Article ID 5208712, Volume 2019 (2019) Broken Lifshitz Invariance, Spin Waves, and Hydrodynamics Dibakar Roychowdhury Research Article (12 pages), Article ID 5356121, Volume 2019 (2019) Dark Energy in Spherically Symmetric Universe Coupled with Brans-Dicke Scalar Field Koijam Manihar Singh and Gauranga C. Samanta Research Article (11 pages), Article ID 5234014, Volume 2019 (2019) Reissner-Nordström Black Holes Statistical Ensembles and First-Order Thermodynamic Phase Transition Hossein Ghaffarnejad and Mohammad Farsam Research Article (15 pages), Article ID 2539217, Volume 2019 (2019) A New Mechanism for Generating Particle Number Asymmetry through Interactions Takuya Morozumi, Keiko I. Nagao, Apriadi Salim Adam , and Hiroyuki Takata Research Article (28 pages), Article ID 6825104, Volume 2019 (2019) Heun-Type Solutions of the Klein-Gordon and Dirac Equations in the Garfinkle-Horowitz-Strominger Dilaton Black Hole Background Marina-Aura Dariescu , Ciprian Dariescu, and Cristian Stelea Research Article (8 pages), Article ID 5769564, Volume 2019 (2019) Models of Anisotropic Self-Gravitating Source in Einstein-Gauss-Bonnet Gravity G. Abbas and M. Tahir Research Article (12 pages), Article ID 7420546, Volume 2018 (2019) Dynamics of Dissipative Viscous Cylindrical Collapse with Full Causal Approach in () Gravity G. Abbas and H. Nazar Research Article (13 pages), Article ID 9250786, Volume 2018 (2019) Hindawi Advances in High Energy Physics Volume 2019, Article ID 1307167, 2 pages https://doi.org/10.1155/2019/1307167 Editorial Implications of Gravitational Particle Creation Subhajit Saha ,1 Kazuharu Bamba,2 and Martiros Khurshudyan 3 1 Department of Mathematics, Panihati Mahavidyalaya, Kolkata 700110, India 2Division of Human Support System, Faculty of Symbiotic Systems Science, Fukushima University, Fukushima 960-1296, Japan 3CAS Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China, Hefei 230026, China Correspondence should be addressed to Subhajit Saha; [email protected] Received 25 July 2019; Accepted 25 July 2019; Published 5 August 2019 Copyright © Subhajit Saha et al. is 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. L. Parker discovered in the early sixties that the expansion origin of DE which is considered to have exotic properties of the Universe can lead to creation of particles out of the such as a huge negative pressure. e Cosmological Constant, vacuum. He pulled together quantum mechanics and general which is supported by most observations as the driving force relativity and found that the expansion of the Universe, or, behind the late time cosmic acceleration, is also plagued in general, a time-variant gravitational field can lead to an by serious problems such as the Cosmological Constant impromptus production of (quantum) particles. e Cosmic problem and coincidence problem. At this juncture, the Microwave Background (CMB) was discovered by Penzias natural process of gravitational particle creation is speculated andWilsonaroundthesametime,whichbroughtnew to explain not only the presently observed accelerated epoch insights into Cosmology and which provided the strongest of the Universe but also the inflationary phase in the early support to the Big-Bang eory. In , the COBE (Cosmic Universe as prophesied by Alan Guth in . In fact, there Background Explorer) satellite detected small fluctuations have been several studies which have confirmed that this in the average temperature of the CMB for the first time. process is well equipped to explain the evolutionary stages of is has later been confirmed by many other experiments, the Universe and is also thermodynamically stable. However, including the Planck satellite. Quantum field theory in curved there are several drawbacks too, the most important one spacetime and, in particular, gravitational particle creation among them is that the exact rate of particle creation has provides the mechanism driving primitive fluctuations which still not been determined. Consequently, researchers mostly created the tiny perturbations in the CMB temperature. e resort to phenomenological considerations to tackle this creation of galaxies and galactic clusters by clumping of problem. Moreover, there have been a very few obser- matter can also be explained by this mechanism. Parker’s vational studies in this direction and more such studies formalism led Hawking to realize that black holes also create are needed to understand this mechanism at a deeper particles, in a way consistent with the laws of thermo- level. dynamics. Hawking’s beautiful result was very influential. In this special issue, we have devoted our attention to It revealed that the second law of thermodynamics was understanding the significance of the gravitationally induced valid for systems that included black holes. is established particle creation mechanism in the context of Cosmology. a deep connection between thermodynamics and general Several authors have made their contributions to this Spe- relativity. cial Issue. We hope that the readers find these articles In recent years, gravitational particle creation is being useful for furthering their research and also gain insights considered as a viable alternative to Dark Energy (DE) models into this very important and rapidly emerging research due to difficulties in identifying the true nature as well as the field. Advances in High Energy Physics Conflicts of Interest All the Guest Editors declare that there is no conflict of interests regarding the publication of this paper. Subhajit Saha Kazuharu Bamba Martiros Khurshudyan Hindawi Advances in High Energy Physics Volume 2019, Article ID 5208712, 7 pages https://doi.org/10.1155/2019/5208712 Research Article Particle Production via Dirac Dipole Moments in the Magnetized and Nonmagnetized Exponentially Expanding Universe Semra Gurtas Dogan,1 Ganim Gecim,2 and Yusuf Sucu 1 1 Department of Physics, Faculty of Science, Akdeniz University, 07058 Antalya, Turkey 2Department of Astronomy and Astrophysics, Faculty of Science, Ataturk¨ Univ., 25240 Erzurum, Turkey Correspondence should be addressed to Yusuf Sucu; [email protected] Received 5 April 2019; Revised 25 June 2019; Accepted 7 July 2019; Published 22 July 2019 Academic Editor: Kazuharu Bamba Copyright © 2019 Semra Gurtas Dogan et al. 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. Te publication of this article was funded by SCOAP3. In the present paper, we solve the Dirac equation in the 2+1 dimensional exponentially expanding magnetized by uniform magnetic feld and nonmagnetized universes, separately. Asymptotic behaviors of the solutions are determined. Using these results we discuss the current of a Dirac particle to discuss the polarization densities and the magnetization density in the context of Gordon decomposition method. In this work we also calculate the total polarization and magnetization, to investigate
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