“When Galaxies Were Born: The Quest for Cosmic Dawn” with Professor Richard Ellis

When Galaxies Were Born book Review on Bridging the Gaps

Looking for the earliest galaxies is like travelling back in time. Something that astronomers do all the time. Astronomers use huge and powerful telescopes to see not only farther and deeper into space, but also back in time. The hunt for the oldest galaxies using observational astronomy needs not only a thorough grasp of the physics and chemistry of the early cosmos, but also the human ingenuity of building large size telescopes and designing innovative instrumentation. Large and complicated telescopes, as well as supporting processes, techniques, and devices, allow astronomers to make more clear and accurate observations in their search for the first galaxies. In his new book “When Galaxies Were Born: The Quest for Cosmic Dawn” professor Richard Ellis presents a firsthand narrative of how a pioneering group of scientists used the world’s greatest telescopes to unravel the history of the universe and witness cosmic dawn, when starlight first illuminated the cosmos and galaxies formed from darkness. The book also gives a narrative of a golden age of astronomy, outlining many achievements and disappointments, and discussing rivalries with competing teams. This is also an account of professor Elis’s remarkable career spanning more than forty years. In this episode of Bridging the Gaps I speak with professor Richard Ellis. We discuss amazing progres that astronomers have made in building ever larger and more powerful telescopes; we also dig deep on the fascinating research on the birth of galaxies and our quest for the cosmic dawn.

Richard S. Ellis is professor of astrophysics at University College London and a world-renowned observational astronomer who has made numerous discoveries about the nature and evolution of the universe.

We start off discussing the human aspects of observational astronomy where teams from all over the world first compete for participating in constructing large telescopes and then compete for securing blocks of time to make observations. We review the taxonomy of large and most powerful ground based telescopes and discuss effectiveness and contribution of space telescopes towards observational astronomy. First light in the universe and the assembly of galaxies in the early universe are among the four main areas that the James Webb Space Telescope will focus on. We dig deep on these points, and what expectations researchers have from this new space telescope. We then discuss how human ingenuity has led to the development of techniques such as adaptive mirrors and application of gravitational lensing to improve our observations. We then focus on the cutting edge research on the quest for cosmic dawn and dig deep on the physics and chemistry of the early universe. We discuss the role dark matter might have played in the formation of early galaxies. We also touch upon the origin of life in the universe, and briefly debate the question “are we alone”. This has been a fun discussion that is highly informative.

Complement this discussion with Exploring the Mysteries of Our Universe’s First Seconds” with Dr Dan Hooper and then listen to “The End of Everything (Astrophysically Speaking)” with Dr Katie Mack.

By |January 29th, 2023|Cosmology, Physics, Podcasts, Technology|

“The End of Astronauts”, Robotic Space Exploration and Our Future on Earth and Beyond with Professor Martin Rees

Human space exploration is challenging as well as fascinating. However, the excitement of space flight for astronauts comes at a high cost and is riddled with danger. As our robot explorers become more capable, governments and corporations must consider whether the ambition to send astronauts to the Moon and Mars is worth the cost and risk. In this episode of Bridging the Gaps, I speak with professor Martin Rees who is one of the authors of “The End of Astronauts: Why Robots Are the Future of Exploration”. The book makes the provocative argument for space exploration without astronauts and suggests that beyond low-Earth orbit, space exploration should proceed without humans. In this discussion, we also touch upon some intriguing points the professor Martin Rees discusses in one of his previous books “On the Future: Prospects for Humanity”.

Martin Rees is an emeritus professor of Cosmology and Astrophysics at the University of Cambridge. He is the UK’s Astronomer Royal, a fellow of Trinity College and a co-founder of the Centre for the Study of Existential Risks at Cambridge University (CSER).

We start by discussing our fascination with human space journeys and exploration. We discuss the title of the book “The End of Astronauts” which seems a bit strong. We then discuss the progress in developing better and smarter robots for robotic space exploration. We discuss the progress made by private space companies in reducing the cost for space missions. Professor Rees emphasise the point that space is hostile and difficult environment and we should avoid using terms as space tourism, instead you should call it space adventures.

We then discuss the book “On the Future: Prospects for Humanity” and touch upon topics such as colonisations of Mars, post human era; genetic engineering and our future on earth and beyond.

Complement this discussion by listening to Everything a Curious Mind Should Know About Planetary Ring Systems with Dr Mark Showalter and then listen to More Things in the Heavens”” with NASA’s Spitzer Project Scientist Michael Werner

By |March 31st, 2022|Cosmology, Future, Physics, Podcasts|

Time, Space and Nature of Reality through the Lens of Quantum Theory with Dr Carlo Rovelli

What is time? Is time real or just an illusion? Time is an enigma, a mystery that never ceases to perplex us. Philosophers, poets, painters and thinkers have long debated its significance, while scientists have discovered that its structure differs from our intuitive understanding of it. Our view of time has changed dramatically throughout the years, from Boltzmann to quantum theory, and from Einstein to loop quantum gravity. In the huge cosmos, time moves at various speeds in different places, the past and future differ considerably less than we might assume, and the whole concept of the present vanishes. In this episode of Bridging the Gaps I discuss with Dr Carlo Rovelli the nature of time, the nature of space, and the fundamental nature of reality through the lens of quantum mechanics.

Carlo Rovelli is professor of physics at Aix-Marseille University, where he is director of the quantum gravity group at the Center for Theoretical Physics. He is one of the founders of loop quantum gravity theory and is one of the world’s biggest experts in this field.

In his books and in his presentations Rovelli says time is not what we think it is. He also says that space is not what we think it is. I open our conversation by asking him to unpack these statements for us. We then discuss the “impossibility of now”. In physics, from one moment to the next, the only concept that gives some notion of continuity is the flow of heat; it is the concept of entropy. We discuss how entropy plays an important role in this perceived continuity. Along the way we touch upon the concepts of past, present and future that we hold in our minds. Dr Rovelli’s new book, Helgoland begins with a detailed description of the development of quantum theory in 1925; we discuss the main observations and discoveries that led to the development of quantum theory. We then discuss the fundamental nature of reality by unpacking the statement in one of his books “if the backdrop of space has disappeared, time has disappeared, classic particles have disappeared, along with the class fields, so then what is the world made of?” And finally we discuss the efforts to develop models and theories to reconcile general relativity with quantum theory. We discuss how loop quantum gravity theory attempts to reconcile general relativity with quantum theory.

Complement this conversion with fascinating discussion with Dr Katie Mack on “The End of Everything” and then list to at: Dr Dan Hooper on “Our Universe’s First Few Seconds”

By |June 13th, 2021|Cosmology, Physics, Podcasts|