Astronomy and Astrophysics - An Introductory Survey, A lecture series by Prof. G. Srinivasan - Lecture 41 - Eternal Inflation and Multiverse

AstroPHYSICS with Srini (https://www.youtube.com/@astrophysicswithsrini1094) The newly launched youtube channel of Prof. Srinivasan. WATCH it, SUBSCRIBE to it, and bring it to the attention of your friends! And here is why. The present course of introductory lectures will end with the 41st lecture. There are many topics in basic physics, as well as astrophysics, that you encountered in this course that deserves a 'revisit'. Prof. Srinivasan plans to make new videos on these topics and upload them to this channel. This will start to happen after the last lecture of this series has been released. Meanwhile, this channel is up. Currently, the PLAYLIST contains the 40 lectures that he delivered at the International Centre for Theoretical Sciences, a few years ago. You are welcome to contact Prof. Srinivasan at [email protected] if you have suggestions for topics, or if you have questions. -------------------------------------------------------------------------------- It’s hard to build models of inflation that don't lead to a multiverse. It’s not impossible, so I think there’s still certainly research that needs to be done. But most models of inflation do lead to a multiverse, and evidence for inflation will be pushing us in the direction of taking [the idea of a] multiverse seriously. ― Alan H. Guth ABOUT THE LECTURE In 1983, Andrei Linde forcefully argued that inflation (exponential expansion) does not require a cosmological phase transition or any contrived potential. Rather, it is a ‘generic cosmological regime’. If one accepts this, then one of the possibilities is that “inflation is eternal” and the universe constantly “reproduces itself”. This is the concept of the MULTIVERSE – an infinitely large number of universes. This raises many questions such as the following. Will the ‘laws of physics' be the same in all the universes? Will the fundamental constants of nature have the same values in all the universes? Was there a beginning to the universe? If so, how did this “creation” happen, and what was there before the beginning? In this final lecture of this series, I shall discuss many of these fascinating but speculative ideas. ABOUT THE LECTURE SERIES This lecture series is organized by the Astronomical Society of India as a part of its Golden Jubilee celebrations. Aimed at undergraduate and graduate students, this series of talks by renowned astrophysicist and teacher, Prof G. Srinivasan, starts from the first principles of Physics and builds up the subject rigorously to the present state of our understanding. Series website: https://astron-soc.in/srini-ana The website hosts a question bank as well as a list of suggested reading for each lecture (prepared by Dr Sushan Konar) ABOUT THE SPEAKER Professor G. Srinivasan In a research career spanning more than five decades, his interests have spanned many aspects of physics and astrophysics. He is a passionate teacher and has authored two outstanding Astronomy texts titled ‘What Are The Stars?’ and ‘Can Stars Find Peace?’ He is a Past President of the Astronomical Society of India, and a Past President of the Division on Space and High Energy Astrophysics of the International Astronomical Union. In his distinguished career he has worked at the University of Chicago, USA; the IBM Research Laboratory in Zurich, Switzerland; Chalmers University of Technology, Goteborg, Sweden; the Cavendish Laboratory, University of Cambridge, England and the Raman Research Institute, Bengaluru Follow us on social media at https://twitter.com/asipoec https://www.facebook.com/asi.poec/ This series is also supported by the IAU OAE Centre in India https://twitter.com/astro4edu_India https://www.facebook.com/OAE-Center-India-105698322030674