Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.4
2.2
Journals
Symmetry
Special Issues
Symmetry: Feature Papers 2024
share announcement

Symmetry: Feature Papers 2024

A special issue of Symmetry (ISSN 2073-8994).

Deadline for manuscript submissions: 31 December 2024 | Viewed by 5975

Special Issue Editor

Prof. Dr. Sergei Odintsov

grade E-Mail Website
Guest Editor
ICREA, 08010 Barcelona and Institute of Space Sciences (IEEC-CSIC), C. Can Magrans s/n, 08193 Barcelona, Spain
Interests: cosmology; dark energy and inflation; classical and quantum gravity; extended gravity; quantum fields in curved spacetime
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

As Editor-in-Chief of the journal Symmetry, I am pleased to announce this Special Issue, entitled “Symmetry: Feature Papers 2024”. In recent years, we have collabortaed with excellent scholars and scientific groups and have published several very important high-level studies which have already been cited numerous times according to the data from Web of Science. Our current aim is to present new insights into scientific developments or cutting-edge technology related to the symmetry field which will make great contributions to the community. Thus, we will continue the Special Issue “Symmetry: Feature Papers” series in 2024.

You are welcome to send short proposals for submissions of Feature Papers to our Editorial Office ([email protected]) before submission. After the proposals have been evaluated, papers may be considered for publication free of charge.

These will firstly be evaluated by our Editors. Please note that selected full papers will still be subject to thorough and rigorous peer review.

Prof. Dr. Sergei Odintsov
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Symmetry is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • computer science
  • mathematics
  • physics
  • chemistry: symmetry/asymmetry
  • life sciences
  • engineering and materials

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Related Special Issue

Published Papers (6 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

21 pages, 318 KiB  
Article
Exact Model of Gravitational Waves and Pure Radiation
by Konstantin E. Osetrin, Vladimir Y. Epp and Altair E. Filippov
Symmetry 2024, 16(11), 1456; https://doi.org/10.3390/sym16111456 - 2 Nov 2024
Viewed by 328
Abstract
An exact non-perturbative model of a gravitational wave with pure radiation is constructed. It is shown that the presence of dust matter in this model contradicts Einstein’s field equations. The exact solution to Einstein’s equations for gravitational wave and pure radiation is obtained. [...] Read more.
An exact non-perturbative model of a gravitational wave with pure radiation is constructed. It is shown that the presence of dust matter in this model contradicts Einstein’s field equations. The exact solution to Einstein’s equations for gravitational wave and pure radiation is obtained. The trajectories of propagation and the characteristics of radiation are found. For the considered exact model of a gravitational wave, a retarded time equation for radiation is obtained. The obtained results are used to construct an exact model of gravitational wave and pure radiation for the Bianchi type IV universe. Full article
(This article belongs to the Special Issue Symmetry: Feature Papers 2024)
25 pages, 323 KiB  
Article
Classification of Petrov Homogeneous Spaces
by V. V. Obukhov
Symmetry 2024, 16(10), 1385; https://doi.org/10.3390/sym16101385 - 17 Oct 2024
Viewed by 383
Abstract
In this paper, the final stage of the Petrov classification is carried out. As it is known, the Killing vector fields specify infinitesimal transformations of the group of motions of space V4. In the case where the group of motions [...] Read more.
In this paper, the final stage of the Petrov classification is carried out. As it is known, the Killing vector fields specify infinitesimal transformations of the group of motions of space V4. In the case where the group of motions G3 acts in a simply transitive way in the homogeneous space V4, the geometry of the non-isotropic hypersurface is determined by the geometry of the transitivity space V3 of the group G3. In this case, the metric tensor of the space V3 can be given by a nonholonomic reper consisting of three independent vectors ℓ(a)α, which define the generators of the group G3 of finite transformations in the space V3. The representation of the metric tensor of V4 spaces by means of vector fields ℓ(a)α has a great physical meaning and makes it possible to substantially simplify the equations of mathematical physics in such spaces. Therefore, the Petrov classification should be complemented by the classification of vector fields ℓ(a)α connected to Killing vector fields. For homogeneous spaces, this problem has been largely solved. A complete solution of this problem is presented in the present paper, where I refine the Petrov classification for homogeneous spaces in which the group G3, which belongs to type VIII according to the Petrov classification, acts simply transitively. In addition, this paper provides the complete classification of vector fields ℓ(a)α for space V4 in which the group G3 acts simply transitivity on isotropic hypersurfaces. Full article
(This article belongs to the Special Issue Symmetry: Feature Papers 2024)
29 pages, 967 KiB  
Article
Schwinger–Keldysh Path Integral Formalism for a Quenched Quantum Inverted Oscillator
by Sayantan Choudhury, Suman Dey, Rakshit Mandish Gharat, Saptarshi Mandal and Nilesh Pandey
Symmetry 2024, 16(10), 1308; https://doi.org/10.3390/sym16101308 - 3 Oct 2024
Cited by 2 | Viewed by 1029
Abstract
In this work, we study the time-dependent behavior of quantum correlations of a system of an inverted oscillator governed by out-of-equilibrium dynamics using the well-known Schwinger–Keldysh formalism in the presence of quantum mechanical quench. Considering a generalized structure of a time-dependent Hamiltonian for [...] Read more.
In this work, we study the time-dependent behavior of quantum correlations of a system of an inverted oscillator governed by out-of-equilibrium dynamics using the well-known Schwinger–Keldysh formalism in the presence of quantum mechanical quench. Considering a generalized structure of a time-dependent Hamiltonian for an inverted oscillator system, we use the invariant operator method to obtain its eigenstate and continuous energy eigenvalues. Using the expression for the eigenstate, we further derive the most general expression for the generating function as well as the out-of-time-ordered correlators (OTOCs) for the given system using this formalism. Further, considering the time-dependent coupling and frequency of the quantum inverted oscillator characterized by quench parameters, we comment on the dynamical behavior, specifically the early, intermediate and late time-dependent features of the OTOC for the quenched quantum inverted oscillator. Next, we study a specific case, where the system of an inverted oscillator exhibits chaotic behavior by computing the quantum Lyapunov exponent from the time-dependent behavior of OTOCs in the presence of the given quench profile. Full article
(This article belongs to the Special Issue Symmetry: Feature Papers 2024)
►▼ Show Figures

Figure 1

19 pages, 1291 KiB  
Article
Enhance Stability of Successive Over-Relaxation Method and Orthogonalized Symmetry Successive Over-Relaxation in a Larger Range of Relaxation Parameter
by Chein-Shan Liu and Chih-Wen Chang
Symmetry 2024, 16(7), 907; https://doi.org/10.3390/sym16070907 - 16 Jul 2024
Viewed by 1063
Abstract
The successive over-relaxation method and its symmetric extension to the symmetric successive over-relaxation method inherit the advantages of direct method and iterative method; they are simple iterative algorithms to solve the linear systems. We derive the equivalent forms of successive over-relaxation method and [...] Read more.
The successive over-relaxation method and its symmetric extension to the symmetric successive over-relaxation method inherit the advantages of direct method and iterative method; they are simple iterative algorithms to solve the linear systems. We derive the equivalent forms of successive over-relaxation method and symmetric successive over-relaxation method in terms of residual vector and descent vector. Then a new orthogonalized technique is developed to stabilize the successive over-relaxation and symmetric successive over-relaxation methods. For the orthogonalized successive over-relaxation method, the range of relaxation parameter can be extended, even with a negative value. Based on the maximal projection technique, the sub-optimal value of the relaxation parameter for the orthogonalized successive over-relaxation method is derived to enhance its accuracy; the golden section search algorithm is used to find the minimal point of a derived merit function. The orthogonalized successive over-relaxation and orthogonalized symmetric successive over-relaxation methods show absolute convergence. According to the new form of successive over-relaxation method, a new approach of the accelerated over-relaxation method can be achieved by multiplying the descent vector of the successive over-relaxation method by a stabilization factor. Numerical examples confirm that the orthogonalized successive over-relaxation and orthogonalized symmetric successive over-relaxation methods outperform the successive over-relaxation and symmetric successive over-relaxation methods. Full article
(This article belongs to the Special Issue Symmetry: Feature Papers 2024)
►▼ Show Figures

Figure 1

20 pages, 1192 KiB  
Article
Exploring the Dynamics of Dark and Singular Solitons in Optical Fibers Using Extended Rational Sinh–Cosh and Sine–Cosine Methods
by Annamalai Muniyappan, Kannan Manikandan, Akbota Saparbekova and Nurzhan Serikbayev
Symmetry 2024, 16(5), 561; https://doi.org/10.3390/sym16050561 - 4 May 2024
Cited by 3 | Viewed by 1234
Abstract
This investigation focuses on the construction of novel dark and singular soliton solutions for the Hirota equation, which models the propagation of ultrashort light pulses in optical fibers. Initially, we employ a wave variable transformation to convert the physical model into ordinary differential [...] Read more.
This investigation focuses on the construction of novel dark and singular soliton solutions for the Hirota equation, which models the propagation of ultrashort light pulses in optical fibers. Initially, we employ a wave variable transformation to convert the physical model into ordinary differential equations. Utilizing extended rational sinh–cosh and sine–cosine techniques, we derive an abundant soliton solution for the transformed system. By plugging these explicit solutions back into the wave transformation, we obtain dark and singular soliton solutions for the Hirota equation. The dynamic evolution of dark soliton profiles is then demonstrated, with a focus on varying physically significant parameters such as wave frequency, strength of third-order dispersion, and wave number. Furthermore, a comprehensive analysis is examined to elucidate how the dark and singular soliton profiles undergo deformation in the background influenced by these arbitrary parameters. The findings presented in this study offer valuable insights that could potentially guide experimental manipulation of dark solitons in optical fibers. Full article
(This article belongs to the Special Issue Symmetry: Feature Papers 2024)
►▼ Show Figures

Figure 1

17 pages, 590 KiB  
Article
Tsallis Holographic Dark Energy with Power Law Ansatz Approach
by Oem Trivedi, Maxim Khlopov and Alexander V. Timoshkin
Symmetry 2024, 16(4), 446; https://doi.org/10.3390/sym16040446 - 7 Apr 2024
Cited by 1 | Viewed by 1287
Abstract
Holographic principles have proven to be a very interesting approach towards dealing with the issues of the late-time acceleration of the universe, which has resulted in a great amount of work on holographic dark energy models. We consider one such very interesting holographic [...] Read more.
Holographic principles have proven to be a very interesting approach towards dealing with the issues of the late-time acceleration of the universe, which has resulted in a great amount of work on holographic dark energy models. We consider one such very interesting holographic scenario, namely the Tsallis Holographic dark energy model, and consider an ansatz based approach to such models. We consider three cosmological scenarios in such models, namely those with viscous, non-viscous, and Chaplygin gas scenarios, discussing various crucial aspects related to these models. We discuss various crucial properties of the Tsallis model in such scenarios and see how the phantom divide is crossed in each case, but it is only the Chaplygin gas models which provide a better view on stability issues.The symmetry property of the theory presented in the article is the assumption that space is isotropic. Using bulk viscosity instead of shear viscosity reflects spatial isotropy. Full article
(This article belongs to the Special Issue Symmetry: Feature Papers 2024)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-6
Back to TopTop