In a groundbreaking collaboration, the  Indian Institute of Technology Guwahati and the University of Stellenbosch, South Africa, are investigating one of the most profound mysteries in physics — the quantum nature of gravity.

 

Led by Dr. Bibhas Ranjan Majhi, Associate Professor, Dept. of Physics at IIT Guwahati, and Dr. Partha Nandi of the University of Stellenbosch, South Africa, the research focuses on gravity-induced entanglement (GIE). The scientists are investigating how gravity behaves at incredibly small scales, such as those of atoms and subatomic particles, where existing theories start to unravel.

Physics currently operates under two separate frameworks. Albert Einstein’s general relativity explains how gravity works for massive objects like planets and stars, describing gravity as the curvature of space and time around these objects. On the other hand, quantum mechanics governs the behavior of particles on the atomic and subatomic levels.

 

Both theories fail to align when it comes to explaining how gravity functions at the quantum level. This disconnect the researchers hope to address through the pursuit of quantum gravity.

 

Dr. Majhi and Dr. Nandi are studying how gravity might lead to entanglement, a phenomenon in quantum mechanics where two particles become linked, such that the state of one affects the other, regardless of the distance between them. The concept of gravity-induced entanglement proposes that under certain conditions, gravitational forces may create this quantum connection, revealing a quantum aspect of gravity.

 

In a statement issued here, Dr. Majhi explained, “We have developed a theoretical framework that connects a two-dimensional quantum harmonic oscillator with gravitational waves—ripples in space-time caused by massive objects like black holes. This approach bypasses the limitations of classical communication methods and explores whether quantized gravitational waves can induce entanglement. Our findings show that while classical gravitational waves do not generate entanglement, the quantum version of these waves does, at the second order of gravitational perturbation.”

 

This research has far-reaching implications. If gravity-induced entanglement can be detected using gravitational wave detectors, it could provide the evidence that gravity operates at a quantum level. Such a discovery could unlock other cosmic mysteries, such as the nature of dark matter and dark energy — two enigmatic components that make up most of the universe but are still poorly understood.