Andrés Aceña, Bruno Cardin Guntsche, Iván Gentile de Austria
{"title":"Revisiting Relativistic Electrically Charged Polytropic Spheres","authors":"Andrés Aceña, Bruno Cardin Guntsche, Iván Gentile de Austria","doi":"10.1002/andp.202400145","DOIUrl":"10.1002/andp.202400145","url":null,"abstract":"<p>The problem of the structure and physical properties of electrically charged static spherically symmetric solutions of the Einstein-Maxwell system of equations is revisited, where the matter model is a polytropic gas. A relativistic polytrope equation of state (EOS) is considered and the electric charge density is assumed to be proportional to the rest mass density. Families of solutions corresponding to various sets of parameters are constructed and analyzed their stability and compliance with the causality requirement, emphasizing the possibility of obtaining black hole mimickers. Concretely, this study wants to test how much electric charge a given object can hold and how compact it can be. It is concluded that there is a microscopic bound on the charge density to rest mass density ratio coincident with the macroscopic bound regarding the extremal Reissner-Nordström (ERN) black hole. The macroscopic charge to mass ratio for the object can exceed the corresponding microscopic ratio if the object is non-extremal. Crucially, the only way to construct a black hole mimicker is by taking a subtle limit in which an electrically counterpoised dust (ECD) solution is attained.</p>","PeriodicalId":7896,"journal":{"name":"Annalen der Physik","volume":"536 12","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Heralded and Complete Interconversion Between W State and Knill–Laflamme–Milburn State via State-Selective Reflection with Robust Fidelity","authors":"Xue-Mei Ren, Jing Guo, Fang-Fang Du","doi":"10.1002/andp.202400215","DOIUrl":"10.1002/andp.202400215","url":null,"abstract":"<p>The interconversion of different types of entangled states not only can realize the information transmission but also play a significant role in quantum information technologies, including increasing scalability and computational power, and reducing error rates. Here, two protocols for achieving a complete interconversion between W state and Knill–Laflamme–Milburn state assisted by the quantum dot (QD)-cavity systems and common quantum control gates are proposed. In particular, the protocols employ a heralded approach strategically designed to predict potential failures and facilitate seamless interaction between the QD-cavity system and photons with the help of a single photon detectors, enhancing experimental accessibility. Through extensive analyzes and evaluations of two protocols, the proposed two protocols achieve remarkable utilization rates of photons (i.e., unit in principle) and achieve near-unit fidelities and high efficiencies in principle.</p>","PeriodicalId":7896,"journal":{"name":"Annalen der Physik","volume":"536 10","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Power Law \u0000 \u0000 \u0000 f\u0000 (\u0000 Q\u0000 )\u0000 \u0000 $f(Q)$\u0000 Cosmology with Bulk Viscous Fluid","authors":"Dheeraj Singh Rana, Raja Solanki, P. K. Sahoo","doi":"10.1002/andp.202400072","DOIUrl":"10.1002/andp.202400072","url":null,"abstract":"<p>In this work, a power law <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>f</mi>\u0000 <mo>(</mo>\u0000 <mi>Q</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$f(Q)$</annotation>\u0000 </semantics></math> model is explored, specifically, <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>f</mi>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mi>Q</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <mo>=</mo>\u0000 <mi>α</mi>\u0000 <msup>\u0000 <mi>Q</mi>\u0000 <mi>n</mi>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$f(Q)= alpha Q^n$</annotation>\u0000 </semantics></math>, along with viscous matter fluid having transport coefficient <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ζ</mi>\u0000 <mo>=</mo>\u0000 <msub>\u0000 <mi>ζ</mi>\u0000 <mn>0</mn>\u0000 </msub>\u0000 <msqrt>\u0000 <mi>Ω</mi>\u0000 </msqrt>\u0000 <mo>+</mo>\u0000 <msub>\u0000 <mi>ζ</mi>\u0000 <mn>1</mn>\u0000 </msub>\u0000 <mi>Ω</mi>\u0000 <mi>H</mi>\u0000 </mrow>\u0000 <annotation>$zeta = zeta _0 sqrt {Omega } + zeta _1 Omega H$</annotation>\u0000 </semantics></math>. The corresponding analytical solution is derived and then confronted with recent cosmic data. The Markov Chain Monte Carlo (MCMC) sampling technique is utilized to estimate the mean value of arbitrary parameters, by incorporating Cosmic Chronometers and recently published Pantheon+Analysis samples. In addition, some cosmological parameters are reconstructed by resampling the chains obtained by emcee, incorporating 6000 samples. It is found that the matter-energy density depicts the expected positive behavior, whereas the effective pressure indicates the negative behavior that is leading the accelerating expansion, which is further predicted in the effective EoS parameter. Further, the asymptotic nature of the assumed model is investigated by invoking phase-space analysis. It is concluded that the assumed viscous <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>f</mi>\u0000 <mo>(</mo>\u0000 <mi>Q</mi>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 <annotation>$f(Q)$</annotation>\u0000 </semantics></math> model successfully predicts an evolution of the universe from decelerated epoch to stable accelerated de-Sitter epoch.</p>","PeriodicalId":7896,"journal":{"name":"Annalen der Physik","volume":"536 11","pages":""},"PeriodicalIF":2.2,"publicationDate":"2024-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142182172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}