In the realm of energy research, understanding the fundamental properties of compact objects like black holes can have significant implications for our comprehension of energy dynamics in the universe. Researchers Benedetta Russo and Alfredo Urbano, affiliated with the University of Rome Tor Vergata, have delved into the intriguing characteristics of exotic compact objects (ECOs) and their potential applications in the solar and sub-solar mass range.
In their recent study, Russo and Urbano have identified a lower limit on the tidal deformability parameter, a measure of how easily an object can be deformed by tidal forces, which is dictated by the principles of relativistic causality. Causality in this context refers to the idea that effects cannot precede their causes, a fundamental concept in the theory of relativity. By also considering the upper bound on compactness, which is a measure of how much mass is concentrated in a given volume, the researchers have mapped out a region in the parameter space where physically motivated ECOs could exist.
The study reveals a notable gap, termed the “tidal gap,” between black holes, which have zero tidal deformability, and these physically plausible ECOs. This discovery prompts the investigation into whether a population of highly compact exotic objects, described by a linear equation of state (EoS), could inhabit both the lower mass gap and the sub-solar region. These objects could mimic primordial black holes but distinguish themselves by their non-zero tidal deformability.
To further explore this concept, the researchers consider solitonic boson stars as proxies for ECOs with a linear EoS. They find that it is possible to reduce the lower limit on the tidal deformability parameter if the strong energy condition is violated, although not the dominant energy condition, which ensures causality is maintained.
The practical applications of this research for the energy sector are still largely theoretical. However, a deeper understanding of the properties and behaviors of compact objects can contribute to our knowledge of energy dynamics in extreme environments, potentially informing future energy technologies and theoretical models. The study was published in the journal Physical Review D, a peer-reviewed publication that covers topics in particle physics, field theory, gravitation, and cosmology.
This article is based on research available at arXiv.