New Insights into Supradense Matter from Dissecting Scaled Stellar Structure Equations

Abstract

The strong-field gravity in General Relativity (GR) realized in neutron stars (NSs) renders the Equation of State (EOS) $P(\epsilon )$ of supradense neutron star (NS) matter to be essentially nonlinear and refines the upper bound for $\varphi \equiv P/\epsilon$ to be much smaller than the Special Relativity (SR) requirement with linear EOSs, where $P$ and $\epsilon$ are respectively the pressure and energy density of the system considered. Specifically, a tight bound $\varphi \lesssim 0.374$ is obtained by anatomizing perturbatively the intrinsic structures of the scaled Tolman--Oppenheimer--Volkoff (TOV) equations without using any input nuclear EOS. New insights gained from this novel analysis provide EOS-model independent constraints on properties (e.g., density profiles of the sound speed squared $s^2=\d P/\d\varepsilon$ and trace anomaly $\Delta =1/3-\varphi$) of cold supradense matter in NS cores. Using the gravity-matter duality in theories describing NSs, we investigate the impact of gravity on supradense matter EOS in NSs. In particular, we show that the NS mass $M_{\mathrm{NS}}$, radius $R$ and its compactness $\xi \equiv M_{\mathrm{NS}}/R$ scale with certain combinations of its central pressure and energy density (encapsulating its central EOS). Thus, observational data on these properties of NSs can straightforwardly constrain NS central EOSs without relying on any specific nuclear EOS-model.

Published version with more references

References in corpus (46)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Many-Body Physics with Ultracold Gases
• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• Multi-messenger Observations of a Binary Neutron Star Merger
• Theory of ultracold Fermi gases
• GW190814: Gravitational Waves from the Coalescence of a 23 M${}_{\odot }$ Black Hole with a 2.6 M${}_{\odot }$ Compact Object
• PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter
• A NICER View of PSR J0030+0451: Millisecond Pulsar Parameter Estimation
• Color superconductivity in dense quark matter
• Neutron Star Observations: Prognosis for Equation of State Constraints
• PSR J0952-0607: The Fastest and Heaviest Known Galactic Neutron Star
• GW170817: Joint Constraint on the Neutron Star Equation of State from Multimessenger Observations
• Cold Quark Matter
• A NICER View of the Nearest and Brightest Millisecond Pulsar: PSR J0437$\unicode{x2013}$4715
• Progress in Constraining Nuclear Symmetry Energy Using Neutron Star Observables Since GW170817
• An updated mass-radius analysis of the 2017-2018 NICER data set of PSR J0030+0451
• Towards Understanding Astrophysical Effects of Nuclear Symmetry Energy
• The Radius of the High-mass Pulsar PSR J0740+6620 with 3.6 yr of NICER Data
• Strongly interacting matter exhibits deconfined behavior in massive neutron stars
• Neutron-star Radius from a Population of Binary Neutron Star Mergers
• Constraining the dense matter equation of state with new NICER mass-radius measurements and new chiral effective field theory inputs
• Bayesian Inference of the Symmetry Energy of Super-Dense Neutron-Rich Matter from Future Radius Measurements of Massive Neutron Stars
• Theoretical and Experimental Constraints for the Equation of State of Dense and Hot Matter
• Confronting GW190814 with hyperonization in dense matter and hypernuclear compact stars
• Determination of the Equation of State from Nuclear Experiments and Neutron Star Observations
• Was GW170817 a canonical neutron star merger? Bayesian analysis with a third family of compact stars
• Evidence against a strong first-order phase transition in neutron star cores: impact of new data
• Phase transitions in neutron stars and their links to gravitational waves
• The neutron star mass, distance, and inclination from precision timing of the brilliant millisecond pulsar J0437$-$4715
• Impact of the equation-of-state -- gravity degeneracy on constraining the nuclear symmetry energy from astrophysical observables
• Probing Quarkyonic Matter in Neutron Stars with the Bayesian Nuclear-Physics Multi-Messenger Astrophysics Framework
• Degeneracy in Studying the Supranuclear Equation of State and Modified Gravity with Neutron Stars
• Central Speed of Sound, Trace Anomaly and Observables of Neutron Stars from Perturbative Analyses of Scaled TOV Equations
• Long Range Plan: Dense matter theory for heavy-ion collisions and neutron stars
• Curvature of the energy per particle in neutron stars
• Core States of Neutron Stars from Anatomizing their Scaled Structure Equations
• How the QCD trace anomaly behaves at the core of twin stars?
• The Intrabinary Shock and Companion Star of Redback Pulsar J2215+5135
• Properties of First-Order Hadron-Quark Phase Transition from Inverting Neutron Star Observables
• Constraining neutron star matter from the slope of the mass-radius curves
• Strong Gravity Extruding Peaks in Speed of Sound Profiles of Massive Neutron Stars
• Maximal Mass Neutron Star as a Key to Superdense Matter Physics
• Neutron star equation of state: identifying hadronic matter characteristics
• Reexamining constraints on neutron star properties from perturbative QCD
• Neutron Star vs Quark Star in the Multimessenger Era

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• Unraveling Trace Anomaly of Supradense Matter via Neutron Star Compactness Scaling
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