Current Science

Rajesh Gopakumar ¹

Affiliations
1 International Centre for Theoretical Sciences-TIFR, Survey No. 151, Shivakote, Hesaraghatta Hobli, Bengaluru 560 089, IN

Abstract

We give a brief survey of the attempts to understand the quantum dynamics of general relativity through the lens of quantum field theory, which has been successfully applied to the other fundamental interactions. This approach began by naively quantizing spin two massless particles but quickly ran into difficulties when considering quantum corrections to the interacting theory. We will describe how the early incarnations of string theory successfully addressed these problems. Then we go on to sketch how one has been able to go beyond this 'perturbative' picture by giving a tight microscopic description of black hole thermodynamics. This in turn has led to the much more subtle holographic description of the quantum dynamics of a large class of spacetimes which has been one of the primary engines of theoretical developments in the last couple of decades.

Keywords

General Relativity, Quantum Dynamics, Quantum Field Theory, String Theory.

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Rajesh Gopakumar ¹, Spenta R. Wadia ¹

Affiliations
1 International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bengaluru 560 089, IN

Abstract

'The gravitational waves were detected on 14 September 2015 at 5:51 a.m. Eastern Daylight Time (09:51 UTC) by both of the twin Laser Interferometer Gravitational-wave Observatory (LIGO) detectors, located in Livingston, Louisiana, and Hanford, Washington, USA.'

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Rajesh Gopakumar ¹, Spenta R. Wadia ¹

Affiliations
1 International Centre for Theoretical Sciences (ICTS-TIFR), Shivakote, Bengaluru 560 089, IN

Abstract

Stephen Hawking, born 8 January 1942, at Oxford in an academic family, had an early aptitude and inclination towards science. He studied physics and chemistry at university in Oxford, though he seems not to have excelled as a student, instead spending much of his time at the college boat club! He went to Cambridge for his Ph D hoping to study cosmology with Fred Hoyle, but instead was assigned to Dennis Sciama who proved to be an important influence on him. It was at this time that Hawking was diagnosed with ALS or Lou Gehrig’s disease – a degenerative motor neuronal disorder. Though he was given only a couple of years to live at age 22 or so, his disease progressed slower than predicted.

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