Primordial naked singularities may offer insights into quantum gravity
by Kiran Ladka
New Delhi (SPX) Jan 13, 2025
Two Indian physicists have introduced a novel theoretical perspective that could reshape our understanding of the universe's composition and offer potential avenues to explore quantum gravity. Professor Pankaj Joshi of Ahmedabad University, India, and Professor Sudip Bhattacharyya of the Tata Institute of Fundamental Research (TIFR), have proposed that the gravitational collapse of matter in the early universe may have produced extraordinarily dense, point-like objects known as visible or naked singularities. This groundbreaking research is set to appear in the Journal of Cosmology and Astroparticle Physics (JCAP).

The origins of the universe, rooted in the explosive Big Bang Singularity, presented extreme conditions with temperatures and densities far beyond current comprehension. Stephen Hawking, building on earlier work by Yakov Zeldovich and Igor Novikov in the 1960s, suggested that quantum fluctuations in the early universe could trigger the gravitational collapse of high-density matter. This process was hypothesized to form primordial black holes (PBHs), theorized to comprise a significant portion of dark matter.

Black holes, as predicted by Einstein's General Relativity, are enigmatic objects without a solid surface, containing matter compressed into near-infinite density. Their defining feature is the event horizon, an invisible boundary beyond which nothing, not even light, can escape, rendering the singularity within unobservable.

While primordial black holes have long been studied for their potential role in dark matter, a crucial component of the universe accounting for five times more mass than visible matter, the precise nature of dark matter remains elusive. Scientists worldwide continue to investigate PBHs and their implications for this enduring mystery.

In their recent research, Joshi and Bhattacharyya propose an alternative outcome of early-universe gravitational collapse - primordial naked singularities (PNaSs). Unlike black holes, PNaSs lack an event horizon, making their singularities observable. These phenomena offer a rare and valuable opportunity to study the extreme conditions of ultra-strong gravity, potentially unlocking new insights into quantum gravity.

Quantum gravity seeks to reconcile the two monumental advancements of 20th-century physics - quantum theory and Einstein's theory of gravity. The observable nature of PNaSs positions them as natural laboratories to explore quantum gravity effects and test theoretical models. If these singularities constitute a significant fraction of dark matter, they could dramatically alter our understanding of the universe, offering a tangible means to investigate its fundamental properties.

The discovery of PNaSs also suggests that a substantial portion of the cosmos might consist of accessible, near-infinitely dense point-like objects. These ancient entities, as old as the universe itself, could transform our perspective on the universe's evolution and provide unprecedented access to the physics of regions previously thought beyond reach.

Research Report:Primordial naked singularities

Related Links
Tata Institute of Fundamental Research
The Physics of Time and Space