Anum Fayyaz , G. Abbas , Awatef Abidi , Arafa A. Yagob
{"title":"带洛伦兹对称性破缺的带电卡尔布-拉蒙黑洞周围弦的混沌动力学","authors":"Anum Fayyaz , G. Abbas , Awatef Abidi , Arafa A. Yagob","doi":"10.1016/j.dark.2025.102125","DOIUrl":null,"url":null,"abstract":"<div><div>The dynamics of a relativistic string close to a charged Kalb-Ramond black hole’s boundary is examined in this article. We show that the development of the string is extremely chaotic and often surpasses the Maldacena–Shenker–Stanford constraint, using the Lyapunov exponent as a diagnostic instrument. Our study also shows that the string’s energy and rotational momentum are crucial in determining its dynamic properties. By increasing the Lorentz symmetry-breaking parameter, the event horizon radius decreases, while the surface gravity increases. Furthermore, when all other parameters are fixed and the angular momentum <span><math><mi>L</mi></math></span> is varied, it is observed that for inner points, increasing <span><math><mi>L</mi></math></span> leads to a decrease in the values of <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> , whereas for outer points, increasing <span><math><mi>L</mi></math></span> results in an increase in <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> . Similarly, when <span><math><mi>L</mi></math></span> and other parameters are kept constant and the energy <span><math><mi>E</mi></math></span> is varied, the behavior differs: for inner points, increasing <span><math><mi>E</mi></math></span> causes <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> to rise, indicating stronger chaotic behavior; in contrast, for outer points, increasing <span><math><mi>E</mi></math></span> leads to a decrease in <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> , suggesting a tendency toward satisfying the Maldacena–Shenker–Stanford bound. Furthermore, we find that a higher energy in the case of outer points suppresses chaotic behavior, as evidenced by a decreasing Lyapunov exponent. These findings contribute to a deeper understanding of chaotic geodesics and the role of Lorentz-symmetry violation in modified gravity frameworks.</div></div>","PeriodicalId":48774,"journal":{"name":"Physics of the Dark Universe","volume":"50 ","pages":"Article 102125"},"PeriodicalIF":6.4000,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Chaotic dynamics of string around a charged Kalb–Ramond black hole with Lorentz symmetry breaking\",\"authors\":\"Anum Fayyaz , G. Abbas , Awatef Abidi , Arafa A. Yagob\",\"doi\":\"10.1016/j.dark.2025.102125\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The dynamics of a relativistic string close to a charged Kalb-Ramond black hole’s boundary is examined in this article. We show that the development of the string is extremely chaotic and often surpasses the Maldacena–Shenker–Stanford constraint, using the Lyapunov exponent as a diagnostic instrument. Our study also shows that the string’s energy and rotational momentum are crucial in determining its dynamic properties. By increasing the Lorentz symmetry-breaking parameter, the event horizon radius decreases, while the surface gravity increases. Furthermore, when all other parameters are fixed and the angular momentum <span><math><mi>L</mi></math></span> is varied, it is observed that for inner points, increasing <span><math><mi>L</mi></math></span> leads to a decrease in the values of <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> , whereas for outer points, increasing <span><math><mi>L</mi></math></span> results in an increase in <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> . Similarly, when <span><math><mi>L</mi></math></span> and other parameters are kept constant and the energy <span><math><mi>E</mi></math></span> is varied, the behavior differs: for inner points, increasing <span><math><mi>E</mi></math></span> causes <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> to rise, indicating stronger chaotic behavior; in contrast, for outer points, increasing <span><math><mi>E</mi></math></span> leads to a decrease in <span><math><mrow><msup><mrow><mi>λ</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>−</mo><msup><mrow><mi>κ</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> , suggesting a tendency toward satisfying the Maldacena–Shenker–Stanford bound. Furthermore, we find that a higher energy in the case of outer points suppresses chaotic behavior, as evidenced by a decreasing Lyapunov exponent. These findings contribute to a deeper understanding of chaotic geodesics and the role of Lorentz-symmetry violation in modified gravity frameworks.</div></div>\",\"PeriodicalId\":48774,\"journal\":{\"name\":\"Physics of the Dark Universe\",\"volume\":\"50 \",\"pages\":\"Article 102125\"},\"PeriodicalIF\":6.4000,\"publicationDate\":\"2025-10-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physics of the Dark Universe\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2212686425003188\",\"RegionNum\":2,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics of the Dark Universe","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2212686425003188","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
Chaotic dynamics of string around a charged Kalb–Ramond black hole with Lorentz symmetry breaking
The dynamics of a relativistic string close to a charged Kalb-Ramond black hole’s boundary is examined in this article. We show that the development of the string is extremely chaotic and often surpasses the Maldacena–Shenker–Stanford constraint, using the Lyapunov exponent as a diagnostic instrument. Our study also shows that the string’s energy and rotational momentum are crucial in determining its dynamic properties. By increasing the Lorentz symmetry-breaking parameter, the event horizon radius decreases, while the surface gravity increases. Furthermore, when all other parameters are fixed and the angular momentum is varied, it is observed that for inner points, increasing leads to a decrease in the values of , whereas for outer points, increasing results in an increase in . Similarly, when and other parameters are kept constant and the energy is varied, the behavior differs: for inner points, increasing causes to rise, indicating stronger chaotic behavior; in contrast, for outer points, increasing leads to a decrease in , suggesting a tendency toward satisfying the Maldacena–Shenker–Stanford bound. Furthermore, we find that a higher energy in the case of outer points suppresses chaotic behavior, as evidenced by a decreasing Lyapunov exponent. These findings contribute to a deeper understanding of chaotic geodesics and the role of Lorentz-symmetry violation in modified gravity frameworks.
期刊介绍:
Physics of the Dark Universe is an innovative online-only journal that offers rapid publication of peer-reviewed, original research articles considered of high scientific impact.
The journal is focused on the understanding of Dark Matter, Dark Energy, Early Universe, gravitational waves and neutrinos, covering all theoretical, experimental and phenomenological aspects.