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Gravitational Waves: What? Why? How?

- Wits University

Wits physicists to explain the significance, relevance and impact of the discovery of Gravitational Waves.

About 100 years after Albert Einstein's prediction – based on his Theory of General Relativity – Gravitational Waves were detected for the first time on September 14, 2015 by the international LIGO collaboration. The discovery was announced on the 11th of February 2016 and was immediately celebrated as a groundbreaking achievement in the field of Physics.

This is a major achievement combining advanced detection technology and theoretical predictions, which will have a profound impact on future astronomical research.

Three Wits experts in physics, Professors Andreas Faltenbacher, Andrew Forbes and Kevin Goldstein will give a public talk, illuminating this discovery from different perspectives. They will explain the relevance, importance and impact of the discovery of Gravitational Waves, and what it means for South Africa. This lecture is expected to be a highly informative, educational and interactive.

What are Gravitational Waves? 

Gravitational Waves are ripples in the curvature of spacetime, which propagate as waves, travelling outward from the source (massive events such as the collisions of black holes). Gravitational Waves were predicted by Albert Einstein in 1916 and the announcement of the discovery was made in February 2016. The announcement caused a social ripple effect with roughly 17 million tweets that followed it. 

The waves came from two black holes that spent aeons circling each other, hurtling closer and closer, before they eventually collided, releasing great shudders of gravitational energy. Those waves — whose  power output briefly exceeded that of all the visible stars in the universe combined — traveled for 1.3 billion years until they washed over the Earth, changing the length of the 4km arms of the LIGO detector by just one-ten-thousandth the diameter of a proton. Scientists believe that this discovery will open a whole new field of study in astronomy and physics.

The talk will be held on 16 March at 17:30 at the Wits Science Stadium, Auditorium 2.