The tune of the universe: the role of plasma in tests of strong-field gravity

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab404 ◽

2021 ◽

Author(s):

Vitor Cardoso ◽

Wen-Di Guo ◽

Caio F B Macedo ◽

Paolo Pani

Keyword(s):

Gravitational Wave ◽

Electromagnetic Waves ◽

Degrees Of Freedom ◽

Strong Field ◽

Low Frequency ◽

Electromagnetic Emission ◽

Modified Theories Of Gravity ◽

Black Hole Binaries ◽

Long Baseline ◽

Electromagnetic Probes

Abstract Gravitational-wave astronomy, together with precise pulsar timing and long baseline interferometry, is changing our ability to perform tests of fundamental physics with astrophysical observations. Some of these tests are based on electromagnetic probes or electrically charged bodies, and assume an empty universe. However, the cosmos is filled with plasma, a dilute medium which prevents the propagation of low-frequency, small-amplitude electromagnetic waves. We show that the plasma hinders our ability to perform some strong-field gravity tests, in particular: (i) nonlinear plasma effects dramatically quench plasma-driven superradiant instabilities; (ii) the contribution of electromagnetic emission to the inspiral of charged black hole binaries is strongly suppressed; (iii) electromagnetic-driven secondary modes, although present in the spectrum of charged black holes, are excited to negligible amplitude in the gravitational-wave ringdown signal. The last two effects are relevant also in the case of massive fields that propagate in vacuum and can jeopardize tests of modified theories of gravity containing massive degrees of freedom.

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Principles of Gravitational-Wave Detection with Pulsar Timing Arrays

Symmetry ◽

10.3390/sym13122418 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2418

Author(s):

Michele Maiorano ◽

Francesco De Paolis ◽

Achille A. Nucita

Keyword(s):

Gravitational Wave ◽

Gravitational Waves ◽

Low Frequency ◽

Black Hole Binaries ◽

Pulsar Timing ◽

Time Correlations ◽

Array Detection ◽

Square Kilometer Array ◽

Gravitational Wave Background ◽

Pulsar Timing Array

Pulsar timing uses the highly stable pulsar spin period to investigate many astrophysical topics. In particular, pulsar timing arrays make use of a set of extremely well-timed pulsars and their time correlations as a challenging detector of gravitational waves. It turns out that pulsar timing arrays are particularly sensitive to ultra-low-frequency gravitational waves, which makes them complementary to other gravitational-wave detectors. Here, we summarize the basics, focusing especially on supermassive black-hole binaries and cosmic strings, which have the potential to form a stochastic gravitational-wave background in the pulsar timing array detection band, and the scientific goals on this challenging topic. We also briefly outline the recent interesting results of the main pulsar timing array collaborations, which have found strong evidence of a common-spectrum process compatible with a stochastic gravitational-wave background and mention some new perspectives that are particularly interesting in view of the forthcoming radio observatories such as the Five hundred-meter Aperture Spherical Telescope, the MeerKAT telescope, and the Square Kilometer Array.

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Accuracy and precision of gravitational-wave models of inspiraling neutron star-black hole binaries with spin: Comparison with matter-free numerical relativity in the low-frequency regime

Physical Review D ◽

10.1103/physrevd.92.102001 ◽

2015 ◽

Vol 92 (10) ◽

Cited By ~ 35

Author(s):

Prayush Kumar ◽

Kevin Barkett ◽

Swetha Bhagwat ◽

Nousha Afshari ◽

Duncan A. Brown ◽

...

Keyword(s):

Black Hole ◽

Neutron Star ◽

Gravitational Wave ◽

Numerical Relativity ◽

Low Frequency ◽

Black Hole Binaries ◽

Accuracy And Precision ◽

Frequency Regime ◽

Wave Models

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The gravitational wave signal from close galaxy pairs

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315008054 ◽

2014 ◽

Vol 10 (S312) ◽

pp. 296-297

Author(s):

Jinzhong Liu ◽

Yu Zhang

Keyword(s):

Gravitational Wave ◽

Low Frequency ◽

Sloan Digital Sky Survey ◽

Population Synthesis ◽

Host Galaxies ◽

Black Hole Binaries ◽

Pulsar Timing ◽

Sky Survey ◽

Square Kilometer Array ◽

Pulsar Timing Array

AbstractThe early phase of coalescence of supermassive black hole binaries (SMBHBs) from their host galaxies provides a guaranteed source of low-frequency gravitational wave (GW) radiation by pulsar timing observations. Nowadays, SMBHBs are ubiquitous in the nuclei of galaxies. A latest sample of close galaxy pairs has been released from the Sloan Digital Sky Survey (SDSS) Data. A binary population synthesis (BPS) approach has been applied to study the characteristics of clusters and galaxies. Here we report how BPS, using SDSS results, can be used to determine the GW radiation from SMBHBs. In this study we show numerical results under the assumption that SMBHBs formed through the merger of two galaxies and give the waveform evolution using post-Newtonian approximation methods. Based on the sensitivity of the International Pulsar Timing Array (IPTA) and Square Kilometer Array (SKA) detectors, we show that the value of strain amplitude h can be changed from about 10−14 to 10−15 during the observation of 20 years, which can be considered as a precise evolution.

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FAST COALESCENCE OF MASSIVE BLACK HOLE BINARIES FROM MERGERS OF GALACTIC NUCLEI: IMPLICATIONS FOR LOW-FREQUENCY GRAVITATIONAL-WAVE ASTROPHYSICS

The Astrophysical Journal ◽

10.1088/2041-8205/732/2/l26 ◽

2011 ◽

Vol 732 (2) ◽

pp. L26 ◽

Cited By ~ 104

Author(s):

Miguel Preto ◽

Ingo Berentzen ◽

Peter Berczik ◽

Rainer Spurzem

Keyword(s):

Black Hole ◽

Gravitational Wave ◽

Low Frequency ◽

Galactic Nuclei ◽

Massive Black Hole ◽

Black Hole Binaries

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SCIENTIFIC POTENTIAL OF DECIGO PATHFINDER AND TESTING GR WITH SPACE-BORNE GRAVITATIONAL WAVE INTERFEROMETERS

International Journal of Modern Physics D ◽

10.1142/s0218271813410137 ◽

2013 ◽

Vol 22 (01) ◽

pp. 1341013 ◽

Cited By ~ 34

Author(s):

KENT YAGI

Keyword(s):

Solar System ◽

Gravitational Wave ◽

Strong Field ◽

Alternative Theories Of Gravity ◽

Black Hole Binaries ◽

Future Space ◽

Stringent Constraint ◽

Scientific Potential ◽

Theories Of Gravity ◽

Alternative Theories

Deci-Hertz Interferometer Gravitational Wave Observatory (DECIGO) Pathfinder (DPF) has an ability to detect gravitational waves (GWs) from galactic intermediate mass black hole binaries. If the signal is detected, it would be possible to determine parameters of the binary components. Furthermore, by using future space-borne GW interferometers, it would be possible to test alternative theories of gravity in the strong field regime. In this review paper, we first explain how the detectors like DPF and DECIGO/BBO work and discuss the expected event rates. Then, we review how the observed gravitational waveforms from precessing compact binaries with slightly eccentric orbits can be calculated both in general relativity and in alternative theories of gravity. For the latter, we focus on Brans–Dicke (BD) and massive gravity (MG) theories. After reviewing these theories, we show the results of the parameter estimation with DPF using the Fisher analysis. We also discuss a possible joint search of DPF and ground-based interferometers. Then, we show the results of testing alternative theories of gravity using future space-borne interferometers. DECIGO/BBO would be able to place 4–5 orders of magnitude stronger constraint on BD theory than the solar system experiment. This is still 1–2 orders of magnitude stronger than the future solar system mission such as ASTROD I. On the other hand, LISA should be able to put four orders of magnitude more stringent constraint on the mass of the graviton than the current solar system bound. DPF may be able to place comparable constraint on the MG theories as the solar system bound. We also discuss the prospects of using eLISA and ASTROD-GW in testing alternative theories of gravity. The bounds using eLISA are similar to the LISA ones, but ASTROD-GW performs the best in constraining MG theories among all the GW detectors considered in this paper.

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Taiji program: Gravitational-wave sources

International Journal of Modern Physics A ◽

10.1142/s0217751x2050075x ◽

2020 ◽

Vol 35 (17) ◽

pp. 2050075 ◽

Cited By ~ 20

Author(s):

Wen-Hong Ruan ◽

Zong-Kuan Guo ◽

Rong-Gen Cai ◽

Yuan-Zhong Zhang

Keyword(s):

Black Hole ◽

Parameter Estimation ◽

Gravitational Wave ◽

Low Frequency ◽

Gravitational Wave Detector ◽

Massive Black Hole ◽

Detection Rates ◽

Black Hole Binaries ◽

Wave Detector

We review potential low-frequency gravitational-wave sources, which are expected to be detected by Taiji, a Chinese space-based gravitational-wave detector, estimate the detection rates of these gravitational-wave sources and present the parameter estimation of massive black hole binaries.

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Gravitational Wave (GW) Classification, Space GW Detection Sensitivities and AMIGO (Astrodynamical Middle-frequency Interferometric GW Observatory)

EPJ Web of Conferences ◽

10.1051/epjconf/201816801004 ◽

2018 ◽

Vol 168 ◽

pp. 01004 ◽

Cited By ~ 8

Author(s):

Wei-Tou Ni

Keyword(s):

Black Holes ◽

Black Hole ◽

Gravitational Wave ◽

Frequency Band ◽

Low Frequency ◽

Spectral Classification ◽

Mass Ratio ◽

Intermediate Mass ◽

Black Hole Binaries ◽

Compact Binaries

After first reviewing the gravitational wave (GW) spectral classification. we discuss the sensitivities of GW detection in space aimed at low frequency band (100 nHz–100 mHz) and middle frequency band (100 mHz–10 Hz). The science goals are to detect GWs from (i) Supermassive Black Holes; (ii) Extreme-Mass-Ratio Black Hole Inspirals; (iii) Intermediate-Mass Black Holes; (iv) Galactic Compact Binaries; (v) Stellar-Size Black Hole Binaries; and (vi) Relic GW Background. The detector proposals have arm length ranging from 100 km to 1.35×109 km (9 AU) including (a) Solar orbiting detectors and (b) Earth orbiting detectors. We discuss especially the sensitivities in the frequency band 0.1-10 μHz and the middle frequency band (0.1 Hz–10 Hz). We propose and discuss AMIGO as an Astrodynamical Middlefrequency Interferometric GW Observatory.

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Propagation of Strong-Field Modulated Electromagnetic Waves in Plasmas

Canadian Journal of Physics ◽

10.1139/p71-381 ◽

1971 ◽

Vol 49 (24) ◽

pp. 3208-3220

Author(s):

M. P. Bachynski ◽

B. W. Gibbs

Keyword(s):

Electron Temperature ◽

Electromagnetic Waves ◽

Strong Field ◽

Plane Electromagnetic Wave ◽

Low Frequency ◽

Wave Form ◽

Plasma Properties ◽

Polarized Waves ◽

Effective Collision Frequency ◽

Low Frequency Waves

The distortion of the wave form of a modulated plane electromagnetic wave propagating in an anisotropic plasma has been experimentally investigated over a range of field strengths of the wave and plasma properties. By using right-hand circularly polarized waves, the effective frequency is [Formula: see text] (where ω is the r.f. radian frequency and ωb the cyclotron frequency) and hence the results are also applicable to the propagation of low-frequency waves in an isotropic plasma. Severe "overmodulation" of the wave form transmitted through the plasma is found in the regime [Formula: see text] where ν is the effective collision frequency for momentum transfer. The distortion of the wave form is found to increase with depth of modulation of the incident wave and decrease with increasing modulation frequency.The "demodulation" is in qualitative agreement with theory for an unmodulated wave with a non-Maxwellian (Druyvesteyn) velocity distribution for the electrons. Many of the effects of the modulation frequencies can also be qualitatively predicted by considering the variation of electron temperature in the presence of the strong-field modulated wave. A theory is developed for large changes in electron temperature induced by the incident field which shows that marked distortion of the modulation is possible.

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Scope Out Multiband Gravitational-Wave Observations of GW190521-Like Binary Black Holes with Space Gravitational Wave Antenna B-DECIGO

Universe ◽

10.3390/universe7030053 ◽

2021 ◽

Vol 7 (3) ◽

pp. 53

Author(s):

Hiroyuki Nakano ◽

Ryuichi Fujita ◽

Soichiro Isoyama ◽

Norichika Sago

Keyword(s):

Black Holes ◽

Gravitational Wave ◽

Frequency Band ◽

Strong Field ◽

Signal To Noise Ratio ◽

Low Frequency ◽

Next Generation ◽

Estimation Errors ◽

Tests Of General Relativity ◽

Wave Signal

The gravitational wave event, GW190521, is the most massive binary black hole merger observed by ground-based gravitational wave observatories LIGO/Virgo to date. While the observed gravitational wave signal is mainly in the merger and ringdown phases, the inspiral gravitational wave signal of the GW190521-like binary will be more visible to space-based detectors in the low-frequency band. In addition, the ringdown gravitational wave signal will be louder in the next generation (3G) of ground-based detectors in the high-frequency band, displaying the great potential of multiband gravitational wave observations. In this paper, we explore the scientific potential of multiband observations of GW190521-like binaries with a milli-Hz gravitational wave observatory: LISA; a deci-Hz observatory: B-DECIGO; and (next generation of) hecto-Hz observatories: aLIGO and ET. In the case of quasicircular evolution, the triple-band observations of LISA, B-DECIGO, and ET will provide parameter estimation errors of the masses and spin amplitudes of component black holes at the level of order of 1–10%. This would allow consistency tests of general relativity in the strong field at an unparalleled precision, particularly with the “B-DECIGO + ET” observation. In the case of eccentric evolution, the multiband signal-to-noise ratio found in “B-DECIGO + ET” observation would be larger than 100 for a five-year observation prior to coalescence, even with high final eccentricities.

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