GUWAHATI, April 9 - The eighth foundation day lecture of the Physics Academy of North East (PANE) was delivered by Prof KD Krori on the topic, �General Relativity and Gravitational Waves,� in the Department of Physics of Gauhati University on Thursday.
Prof Krori elucidated the Theory of Relativity from the concept of relative motion. He explained that uniform relative motion leads to the Theory of Special Relativity and relative non-uniform motion leads to the Theory of General Relativity. He elaborated how the principle of relativity and the universal constancy of the speed of light in vacuum have to be accepted as two essential postulates for the Special Theory of Relativity.
Prof Krori showed why tensor calculus was an essential tool for General Relativity and why General Relativity was intimately linked to a new theory of gravitation according to which gravitation manifests itself as curvature of space time. He narrated some phenomena predicted by this theory of gravitation and later confirmed from observations, the latest of them being gravitational waves detected in February 2016 � 100 years after Einstein�s prediction.
Prof Krori also discussed in detail the gravitational waves, which were the ripples in the fabric of space time and the basic principles of LIGO (Laser Interferometer Gravitational Observatory) which detected such feeble waves in a unique way.
�It took 100 years to detect gravitational waves after Einstein predicted them in 1916. Since the gravitational waves created by the collision of two super-massive black holes situated at 1.3 billion light years away is extremely weak, a lot of trial and error was necessary to design and devise a unique detector which will have a high degree of precision to detect such a small signal and ultimately, LIGO did that work perfectly. Thanks to the creative genius of Einstein!� Prof Krori said.
The audience comprised faculty members of the Gauhati University as well as other institutions, research scholars, postgraduate students, a large number of PANE life members and students from various other institutions.