Research

Physical Sciences

Title :

Investigating tidal interaction between white dwarfs and intermediate-mass black holes as an astrophysical tool to test modified gravity theories.

Area of research :

Physical Sciences

Principal Investigator :

Dr. Pritam Banerjee, Indian Institute Of Technology (IIT) Kharagpur, West Bengal

Timeline Start Year :

2023

Timeline End Year :

2025

Contact info :

Details

Executive Summary :

Tidal fields, resulting from the inhomogeneity of gravity, can cause tidal deformation and disruption of stars. Observation of luminous flares emitted from disrupted materials during accretion processes can help infer properties of the disrupted stellar object, such as mass, compactness, equation of state, and the mass and spin of the central black hole. Tidal deformation during the inspiral motion of compact binaries determines their orbital dynamics and gravitational wave signature. Intermediate-mass black hole (IMBH) and white dwarf (WD) interactions are important in this regard, as they can produce both gravitational wave and electromagnetic signals due to tidal disruptions or tidal stripping of WDs. IMBHs are important seeds to explain the presence of supermassive black holes (SMBH), but evidence of IMBHs is elusive. The tidal interaction of a WD is important in this context, as IMBHs can disrupt WDs not disrupted by SMBHs. The presence of modified gravity changes the mass-radius relation of a WD by a significant amount, which can impact gravitational interactions of astrophysical objects. If modified gravity can weaken or strengthen internal gravity inside astrophysical objects, it can impact gravitational interactions, such as tidal interactions and gravitational wave emissions. To find answers to these questions, modified gravity influences the tidal radius of an IMBH-WD interaction, which increases proportionally with WD radius. This information can provide information about the mass and radius of the white dwarf that is necessary to generate observed luminosity and GW signal, verifying the influence of modified gravity on the expected WD properties.

Organizations involved