<p>While Einstein’s theory about the existence of gravitational waves has been proven through the now popular LIGO project, a theory proposed by a Bengaluru scientist about ‘quasi-normal modes’ or scattered waves from the black holes 45 years ago, has also come true through the discovery.<br /><br /></p>.<p>Years ago, even before the term ‘black holes’ was in common parlance among astrophysicists and cosmologists, Prof C V Vishveswara, a black-hole physicist, started his work on the subject from around 1968 onwards, making major contributions to the nature and structure of the black holes.<br /><br />“Back then, everything was pure theory and there was no possibility of experiments like now. When I wrote my first paper, even the term had not been used properly. John Wheeler (noted theoretical physicist), who was my guru’s guru, popularised the term and it caught on. I myself used the term while writing my third paper on the scattering of gravitational waves,” he said.<br /><br />He spoke to Deccan Herald on the sidelines of a programme in the City.<br /><br />The LIGO project, while discovering the gravitational waves, also detected quasi-normal modes, something Prof Vishveswara had written about in the scientific journal ‘Nature’ in 1970. Prof Bala Iyer, a theoretical physicist at the Raman Research Institute, who is also a member of the LIGO Scientific Collaboration and chairperson of the IndiGO consortium, the gravitational wave community in India, said: <br /><br />“The understanding is that nothing comes out of a black hole. So, how do you know about its existence? He (Vishveswara) had the idea that if there is a black hole, there will be some signatures of the black hole.” While the discovery of the gravitational waves is referred to as a “chirp”, <br /><br />Prof Iyer said quasi-normal modes were more like the ringing of the bell with a certain frequency and decay. “He (Vishveswara) was one of the first persons who prophesied that by looking at quasi-normal modes, one can say something about the properties of the black holes. This has also been mentioned in the study about gravitational waves,” he said.<br /></p>
<p>While Einstein’s theory about the existence of gravitational waves has been proven through the now popular LIGO project, a theory proposed by a Bengaluru scientist about ‘quasi-normal modes’ or scattered waves from the black holes 45 years ago, has also come true through the discovery.<br /><br /></p>.<p>Years ago, even before the term ‘black holes’ was in common parlance among astrophysicists and cosmologists, Prof C V Vishveswara, a black-hole physicist, started his work on the subject from around 1968 onwards, making major contributions to the nature and structure of the black holes.<br /><br />“Back then, everything was pure theory and there was no possibility of experiments like now. When I wrote my first paper, even the term had not been used properly. John Wheeler (noted theoretical physicist), who was my guru’s guru, popularised the term and it caught on. I myself used the term while writing my third paper on the scattering of gravitational waves,” he said.<br /><br />He spoke to Deccan Herald on the sidelines of a programme in the City.<br /><br />The LIGO project, while discovering the gravitational waves, also detected quasi-normal modes, something Prof Vishveswara had written about in the scientific journal ‘Nature’ in 1970. Prof Bala Iyer, a theoretical physicist at the Raman Research Institute, who is also a member of the LIGO Scientific Collaboration and chairperson of the IndiGO consortium, the gravitational wave community in India, said: <br /><br />“The understanding is that nothing comes out of a black hole. So, how do you know about its existence? He (Vishveswara) had the idea that if there is a black hole, there will be some signatures of the black hole.” While the discovery of the gravitational waves is referred to as a “chirp”, <br /><br />Prof Iyer said quasi-normal modes were more like the ringing of the bell with a certain frequency and decay. “He (Vishveswara) was one of the first persons who prophesied that by looking at quasi-normal modes, one can say something about the properties of the black holes. This has also been mentioned in the study about gravitational waves,” he said.<br /></p>
