Year: 2018
Type: article
Abstract: Gravitational waves from spin-precessing binaries exhibit amplitude oscillations that provide an invaluable method to extract the spins of the inspiraling compact objects. The spin-spin and spin-orbit interactions that cause this effect are sensitive to the fundamental nature of gravity, which will allow us to constrain modified theories of gravity using gravitational wave observations of precessing binaries. We here consider precessing black hole binaries in dynamical Chern-Simons gravity, an effective theory of gravity that enhances parity violating interactions. We model the black holes as modified point particles using effective field theory, and derive the spin-precession equations for a binary system by working within the post-Newtonian formalism. We find that the spin-spin and quadrupole-monopole interactions of general relativity are modified due to an interaction between the scalar dipoles of the two black holes and the modified black hole quadrupole as a result of the violation of the no hair theorems. These modifications enter the precession equations at leading post-Newtonian order. We further show that these precession equations admit seven constants of motion when neglecting radiation reaction, with only the mass-weighted effective spin being modified from general relativity. We discuss how these may be used to reduce the precession equations to quadrature and the possibility of constructing analytic Fourier domain waveforms for generic spin-precessing binaries in dCS gravity.
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: CAREER: Gravitational Waves from Compact Binaries as Probes of the Universe, G192509961, G2276001160, Theoretical foundation of higher order cosmological perturbation, G2652818788, THIS PROPOSAL IS FOCUSED ON (I) NUCLEAR PHYSICS IN EXTREME GRAVITY (II) EXPERIMENTAL RELATIVITY IN EXTREME GRAVITY AND (III) MULTIMESSENGER ASTROPHYSICS IN EXTREME GRAVITY. REGARDING (I) WE PROPOSE TO IMPROVE AND DEVELOP NEW TOOLS TO EXTRACT THE MOST ASTROPHYSICS FROM X-RAY DATA OBTAINED WITH NASA'S NEUTRON STAR INTERIOR COMPOSITION EXPLORER (NICER). THESE TOOLS WILL ALLOW FOR PRECISE CONSTRAINTS ON THE NEUTRON STAR EQUATION OF STATE THROUGH MEASUREMENTS OF THEIR MASS AND RADIUS. REGARDING (II) WE PROPOSE TO CREATE A FRAMEWORK THROUGH WHICH TO TEST GENERAL RELATIVITY WITH BOTH GRAVITATIONAL WAVE DATA FROM THE LASER INTERFEROMETER SPACE ANTENNA (LISA) AND X-RAY DATA FROM NICER IN A ROBUST AND MODEL-INDEPENDENT FASHION. THIS FRAMEWORK WILL ALLOW FOR CONSISTENCY CHECKS OF EINSTEIN'S THEORY AND THE SEARCH FOR MODIFIED GRAVITY ANOMALIES WITH NEUTRON STARS AND BLACK HOLES. REGARDING (III) WE PROPOSE TO LEARN ABOUT NUCLEAR PHYSICS AND GENERAL RELATIVITY BY COMBINING X-RAY INFORMATION FROM NICER GAMMA-RAY INFORMATION FROM NASA'S FERMI AND SWIFT TELESCOPES AND GRAVITATIONAL WAVE INFORMATION FROM ADVANCED LIGO. THE PROPOSED WORK IS OF DIRECT RELEVANCE TO NASA'S STRATEGIC MISSION TO BETTER UNDERSTAND THE UNIVERSE THROUGH OBSERVATION AND NASA'S MISSION OF DISCOVERY AND KNOWLEDGE. THE REGION OF THE UNIVERSE WHERE GRAVITY IS UNBEARABLY STRONG AND DYNAMICALLY CHANGING (THE EXTREME GRAVITY UNIVERSE) IS ONE OF THE LAST UNTURNED STONES. THIS IS IN PART BECAUSE EXTREME GRAVITY OBJECTS LIKE NEUTRON STARS AND BLACK HOLES ARE DIFFICULT TO RESOLVE DUE TO THEIR SIZE AND DISTANCE FROM EARTH. NASA'S INVESTMENTS IN NEUTRON STAR ASTROPHYSICS AND IN SPACE-BORNE GRAVITATIONAL WAVE ASTROPHYSICS ARE AIMED AT RESOLVING SUCH OBJECTS AND FOR THE FIRST TIME EXPLORING THE EXTREME GRAVITY UNIVERSE IN DETAIL. THE FOCUS OF THIS PROPOSAL IS TO AID IN THIS ENDEAVOR BY DEVELOPING THE TOOLS AND THE UNDERSTANDING NEEDED TO EXTRACT THE MOST INFORMATION FROM THE DATA., EAPSI: Investigating Spinning Black Holes in a Modified Theory of Gravity, G4174527812, A SPACE BASED GRAVITATIONAL WAVE DETECTOR WILL OPEN UP THE SOURCE RICH LOW FREQUENCY PORTION OF THE SPECTRUM THAT CAN NOT BE ACCESSED FROM THE GROUND, Construction of bread board model of space gravitational wave interferometer DECIGO, G8010103073, G8157362042
OpenAlex ID: W2604337690