Cosmology in theories with spontaneous scalarization of neutron stars

Abstract

In a model of spontaneous scalarization of neutron stars proposed by Damour and Esposite-Farese, a general relativistic branch becomes unstable to trigger tachyonic growth of a scalar field $\varphi$ toward a scalarized branch. Applying this scenario to cosmology, there is fatal tachyonic instability of $\varphi$ during inflation and matter dominance being incompatible with solar-system constraints on today's field value ${\varphi }_0$. In the presence of a four-point coupling $g^2{\varphi }^2{\chi }^2/2$ between $\varphi$ and an inflaton field $\chi$, it was argued by Anson et al. that a positive mass squared heavier than the square of a Hubble expansion rate leads to the exponential suppression of $\varphi$ during inflation and that ${\varphi }_0$ can remain small even with the growth of $\varphi$ after the radiation-dominated epoch. For several inflaton potentials approximated as $V(\chi )=m^2{\chi }^2/2$ about the potential minimum, we study the dynamics of $\varphi$ during reheating as well as other cosmological epochs in detail. For certain ranges of the coupling $g$, the homogeneous field $\varphi$ can be amplified by parametric resonance during a coherent oscillation of the inflaton. Incorporating the backreaction of created particles under a Hartree approximation, the maximum values of $\varphi$ reached during preheating are significantly smaller than those obtained without the backreaction. We also find that the minimum values of $g$ consistent with solar system bounds on $\varphi$ at the end of reheating are of order $10^{-5}$ and hence there is a wide range of acceptable values of $g$. Thus, the scenario proposed by Anson et al. naturally leads to the viable cosmological evolution of $\varphi$ consistent with local gravity constraints, without modifying the property of scalarized neutron stars.

arXiv comment15 pages, 8 figures

References in corpus (59)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Dynamics of dark energy
• Modified Gravity and Cosmology
• The Confrontation between General Relativity and Experiment
• f(R) theories
• Planck 2018 results. X. Constraints on inflation
• Towards the Theory of Reheating After Inflation
• Reheating after Inflation
• Chameleon Cosmology
• GW190425: Observation of a Compact Binary Coalescence with Total Mass $\sim 3.4M_{\odot }$
• Testing General Relativity with Present and Future Astrophysical Observations
• Beyond the Cosmological Standard Model
• Generalized G-inflation: Inflation with the most general second-order field equations
• From k-essence to generalised Galileons
• Inflation Dynamics and Reheating
• Universe Reheating after Inflation
• Black holes, gravitational waves and fundamental physics: a roadmap
• Superconformal Inflationary $\alpha$-Attractors
• Tensor-scalar gravity and binary-pulsar experiments
• The relativistic pulsar-white dwarf binary PSR J1738+0333 II. The most stringent test of scalar-tensor gravity
• What is the lowest possible reheating temperature?
• General second order scalar-tensor theory, self tuning, and the Fab Four
• A systematic approach to generalisations of General Relativity and their cosmological implications
• MeV-scale reheating temperature and thermalization of oscillating neutrinos by radiative and hadronic decays of massive particles
• Neutron-star mergers in scalar-tensor theories of gravity
• Extreme Gravity Tests with Gravitational Waves from Compact Binary Coalescences: (I) Inspiral-Merger
• Constraints on Perturbative f(R) Gravity via Neutron Stars
• Dark energy in Horndeski theories after GW170817: A review
• Lattice study of classical inflaton decay
• Neutron Stars in f(R) Gravity with Perturbative Constraints
• Constraints on scalar-tensor models of dark energy from observational and local gravity tests
• The Universe after inflation: the wide resonance case
• Resonant decay of Bose condensates
• Neutron stars in scalar-tensor theories of gravity and catastrophe theory
• On neutron stars in f(R) theories: small radii, large masses and large energy emitted in a merger
• Post-Inflation Reheating in an Expanding Universe
• Probing Strong-Field Scalar-Tensor Gravity with Gravitational Wave Asteroseismology
• Constraining nonperturbative strong-field effects in scalar-tensor gravity by combining pulsar timing and laser-interferometer gravitational-wave detectors
• Structure of neutron stars in R-squared gravity
• Neutron star transition to strong-scalar-field state in tensor scalar gravity
• The Novel Probes Project -- Tests of Gravity on Astrophysical Scales
• Super-horizon perturbations and preheating
• Resonant particle production with non-minimally coupled scalar fields in preheating after inflation
• The Effect of Cosmological Evolution on Solar System Constraints and on the Scalarization of Neutron Stars in Massless Scalar-Tensor Theories
• On Metric Preheating
• When can preheating affect the CMB?
• Binary Pulsar constraints on massless scalar-tensor theories using Bayesian statistics
• Constraining scalar-tensor theories by neutron star-balck hole gravitational wave events
• Neutron stars with a generalized Proca hair and spontaneous vectorization
• Compact object scalarization with general relativity as a cosmic attractor
• Neutron stars in $f(R)$ gravity and scalar-tensor theories
• On generation of metric perturbations during preheating
• Cosmological instability of scalar-Gauss-Bonnet theories exhibiting scalarization
• Stability of relativistic stars with scalar hairs
• Reconciling spontaneous scalarization with cosmology
• Cosmology with subdominant Horndeski scalar field
• Cosmological attractors to general relativity and spontaneous scalarization with disformal coupling
• Inflation with mixed helicities and its observational imprint on CMB

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