Constraining parity violation in gravity with measurements of neutron-star moments of inertia

Journal Article · Mon Mar 15 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.064020· OSTI ID:21409408

Yunes, Nicolas ^[1]; Psaltis, Dimitrios; Oezel, Feryal ^[2]; Loeb, Abraham ^[3]

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1. Department of Physics, Princeton University, Princeton, New Jersey 08544 (United States)
2. Department of Astronomy, University of Arizona, Tucson, Arizona 85721 (United States)
3. Institute for Theory and Computation (ITC), Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States)

Neutron stars are sensitive laboratories for testing general relativity, especially when considering deviations where velocities are relativistic and gravitational fields are strong. One such deviation is described by dynamical, Chern-Simons modified gravity, where the Einstein-Hilbert action is modified through the addition of the gravitational parity-violating Pontryagin density coupled to a field. This four-dimensional effective theory arises naturally both in perturbative and nonperturbative string theory, loop quantum gravity, and generic effective field theory expansions. We calculate here Chern-Simons modifications to the properties and gravitational fields of slowly spinning neutron stars. We find that the Chern-Simons correction affects only the gravitomagnetic sector of the metric to leading order, thus introducing modifications to the moment-of-inertia but not to the mass-radius relation. We show that an observational determination of the moment-of-inertia to an accuracy of 10%, as is expected from near-future observations of the double pulsar, will place a constraint on the Chern-Simons coupling constant of {xi}{sup 1/4} < or approx. 5 km, which is at least three-orders of magnitude stronger than the previous strongest bound.

• OSTI ID: 21409408
• Journal Information: Physical Review. D, Particles Fields, Vol. 81, Issue 6; Other Information: DOI: 10.1103/PhysRevD.81.064020; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCURACY
CORRECTIONS
COUPLING CONSTANTS
DENSITY
EXPANSION
FOUR-DIMENSIONAL CALCULATIONS
GENERAL RELATIVITY THEORY
GRAVITATIONAL FIELDS
MASS
METRICS
MOMENT OF INERTIA
NEUTRON STARS
PARITY
PULSARS
QUANTUM FIELD THEORY
QUANTUM GRAVITY
RELATIVISTIC RANGE
STRING MODELS
COMPOSITE MODELS
COSMIC RADIO SOURCES
ENERGY RANGE
EXTENDED PARTICLE MODEL
FIELD THEORIES
MATHEMATICAL MODELS
PARTICLE MODELS
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
QUARK MODEL
RELATIVITY THEORY
STARS