Geometric Constraints on the Speed of Sound and Properties of Neutron Stars

Geometric Constraints on the Speed of Sound and Properties of Neutron Stars | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Geometric Constraints on the Speed of Sound and Properties of Neutron Stars M. Bousder, E. Salmani, A. Riadsolh, M. El Belkacemi, H. Ez-Zahraouy This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4006727/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract We investigate solutions to the Tolman-Oppenheimer-Volkoff equations and their implications, deriving an equation of state for the star’s surface as a function of two geometric parameters, λ(r) and ν(r). We find that the parameter λ(r) is essential for explaining fluctuations in the baryon number density and baryonic chemical potential within and outside a neutron star, enabling simulations of regions with varying neutron matter densities. We also highlight the significant role of the ν(r) parameter in illustrating the transition from a neutron star to a black hole, establishing a direct connection between the neutron star’s radius and the event horizon’s radius. The parameter λ(r) is crucial for understanding how the baryon number density and baryonic chemical potential fluctuate inside and outside a neutron star. The core is characterized by λ > 0, and the outer crust is defined by λ < 0. Finally, by analyzing the polytropic equation of state, we find that the neutron stars are composed of two distinct regions: a low-density outer crust and a very high-density core, separated by a sharp boundary. The mixing region between the two layers is known as the inner crust and outer core. Neutron stars black hole neutron matter Polytrope Tolman Oppenheimer Volkoff equations Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4006727","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":276327462,"identity":"578403aa-1a3e-4622-b655-6cb2b7f7285a","order_by":0,"name":"M. 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We find that the parameter λ(r) is essential for explaining fluctuations in the baryon number density and baryonic chemical potential within and outside a neutron star, enabling simulations of regions with varying neutron matter densities. We also highlight the significant role of the ν(r) parameter in illustrating the transition from a neutron star to a black hole, establishing a direct connection between the neutron star’s radius and the event horizon’s radius. The parameter λ(r) is crucial for understanding how the baryon number density and baryonic chemical potential fluctuate inside and outside a neutron star. The core is characterized by λ \u0026gt; 0, and the outer crust is defined by λ \u0026lt; 0. Finally, by analyzing the polytropic equation of state, we find that the neutron stars are composed of two distinct regions: a low-density outer crust and a very high-density core, separated by a sharp boundary. 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