{"title":"瑞士奶酪链上的对数膨胀与变化的宇宙常数","authors":"Nasr Ahmed, Anirudh Pradhan","doi":"10.1134/S0202289324700415","DOIUrl":null,"url":null,"abstract":"<p>The existence of Schwarzschild black holes in the structure of a Swiss-cheese brane world has led to the conclusion that this specific brane-world scenario is more realistic than the FLRW branes. In this paper, we show that Logamediate inflation on the Swiss-cheese brane with a time-dependent cosmological constant <span>\\(\\Lambda(H)\\)</span> leads to a positive kinetic term and a negative potential with AdS minimum. The cosmic pressure <span>\\(p\\)</span> is always positive, but the energy density <span>\\(\\rho\\)</span> starts to get negative after finite time. However, there is a time interval where they both are positive. Although this behavior of <span>\\(\\rho\\)</span> can be considered as a drawback of the Swiss-cheese brane, where positive energy dominates the present universe, it has been suggested that the presence of some source of negative energy could have played a significant role in the early cosmic expansion. The model suffers from the eternal inflation problem which appears from the evolution of the first slow-roll parameter <span>\\(\\epsilon\\)</span>. Due to the existence of the <span>\\(\\rho^{2}\\)</span> term, we have tested the new nonlinear energy conditions. The slow-roll parameters have been investigated and compared to Planck 15 results.</p>","PeriodicalId":583,"journal":{"name":"Gravitation and Cosmology","volume":"30 4","pages":"523 - 535"},"PeriodicalIF":1.2000,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Logamediate Inflation on the Swiss-Cheese Brane with Varying Cosmological Constant\",\"authors\":\"Nasr Ahmed, Anirudh Pradhan\",\"doi\":\"10.1134/S0202289324700415\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>The existence of Schwarzschild black holes in the structure of a Swiss-cheese brane world has led to the conclusion that this specific brane-world scenario is more realistic than the FLRW branes. In this paper, we show that Logamediate inflation on the Swiss-cheese brane with a time-dependent cosmological constant <span>\\\\(\\\\Lambda(H)\\\\)</span> leads to a positive kinetic term and a negative potential with AdS minimum. The cosmic pressure <span>\\\\(p\\\\)</span> is always positive, but the energy density <span>\\\\(\\\\rho\\\\)</span> starts to get negative after finite time. However, there is a time interval where they both are positive. Although this behavior of <span>\\\\(\\\\rho\\\\)</span> can be considered as a drawback of the Swiss-cheese brane, where positive energy dominates the present universe, it has been suggested that the presence of some source of negative energy could have played a significant role in the early cosmic expansion. The model suffers from the eternal inflation problem which appears from the evolution of the first slow-roll parameter <span>\\\\(\\\\epsilon\\\\)</span>. Due to the existence of the <span>\\\\(\\\\rho^{2}\\\\)</span> term, we have tested the new nonlinear energy conditions. The slow-roll parameters have been investigated and compared to Planck 15 results.</p>\",\"PeriodicalId\":583,\"journal\":{\"name\":\"Gravitation and Cosmology\",\"volume\":\"30 4\",\"pages\":\"523 - 535\"},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2024-11-22\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Gravitation and Cosmology\",\"FirstCategoryId\":\"4\",\"ListUrlMain\":\"https://link.springer.com/article/10.1134/S0202289324700415\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Gravitation and Cosmology","FirstCategoryId":"4","ListUrlMain":"https://link.springer.com/article/10.1134/S0202289324700415","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
Logamediate Inflation on the Swiss-Cheese Brane with Varying Cosmological Constant
The existence of Schwarzschild black holes in the structure of a Swiss-cheese brane world has led to the conclusion that this specific brane-world scenario is more realistic than the FLRW branes. In this paper, we show that Logamediate inflation on the Swiss-cheese brane with a time-dependent cosmological constant \(\Lambda(H)\) leads to a positive kinetic term and a negative potential with AdS minimum. The cosmic pressure \(p\) is always positive, but the energy density \(\rho\) starts to get negative after finite time. However, there is a time interval where they both are positive. Although this behavior of \(\rho\) can be considered as a drawback of the Swiss-cheese brane, where positive energy dominates the present universe, it has been suggested that the presence of some source of negative energy could have played a significant role in the early cosmic expansion. The model suffers from the eternal inflation problem which appears from the evolution of the first slow-roll parameter \(\epsilon\). Due to the existence of the \(\rho^{2}\) term, we have tested the new nonlinear energy conditions. The slow-roll parameters have been investigated and compared to Planck 15 results.
期刊介绍:
Gravitation and Cosmology is a peer-reviewed periodical, dealing with the full range of topics of gravitational physics and relativistic cosmology and published under the auspices of the Russian Gravitation Society and Peoples’ Friendship University of Russia. The journal publishes research papers, review articles and brief communications on the following fields: theoretical (classical and quantum) gravitation; relativistic astrophysics and cosmology, exact solutions and modern mathematical methods in gravitation and cosmology, including Lie groups, geometry and topology; unification theories including gravitation; fundamental physical constants and their possible variations; fundamental gravity experiments on Earth and in space; related topics. It also publishes selected old papers which have not lost their topicality but were previously published only in Russian and were not available to the worldwide research community