Monster Black Holes at the Edge of the Universe

Thu Feb 15, 2024, 7:00PM ET

Zoltan Haiman, Professor of Physics and Astronomy, Columbia University

Black holes as massive as several billion solar masses appeared within a billion years after the Big Bang. The origin of these objects remains a mystery. I will present state-of-the art speculations on how such massive black holes may have formed in the early universe from black hole remnants of the first stars, via rapid gas accretion, or via successive mergers. Observations with the recently launched James Webb Space Telescope (JWST) and with the space-based gravitational-wave detector called Laser Interferometer Space Antenna (LISA) will help us understand the origin of massive black holes, as well as their subsequent growth through gas accretion and mergers.

Photo caption: When two black holes orbit one another in the nucleus of a galaxy, they stir the surrounding material into unique patterns. This can help push the black holes together to collide and merge.

Ice Fishing in Antarctica for Astrophysical Neutrinos

Thu Mar 21, 2024, 7:00PM ET

Ibrahim Safa, Post-doctoral Research Scientist, Columbia University

Neutrinos, elusive weakly interacting fundamental particles, were only discovered in the latter half of the 20th century. Since then, they have turned up surprises at every junction. With their unusual properties, neutrinos challenge our current understanding of particle physics and hold potential to unravel new paradigms. In 2010, construction was completed to instrument one billion tons of ice at the geographic South Pole to search for high-energy neutrinos coming from the vicinities of supermassive black holes.

My talk will describe this unusual fishing expedition. I will discuss why neutrinos are a great astronomical messenger, and what information they carry from their sources billions of light years away. I will explain why it was necessary to go to the South Pole to capture these particles, and discuss the construction and operation of the IceCube experiment. I will highlight some of the major discoveries made since IceCube’s inception, and briefly touch on the future potential of neutrino astronomy in the next generation of experiments.

At the Speed of Volcanic Eruptions

Thu Apr 11, 2024, 7:00PM ET

Terry Plank, Arthur D. Storke Memorial Professor of Geochemistry, Columbia University

What happens under volcanoes in the months, days and minutes leading up to eruption? How does magma prepare for an eruption? And why are some eruptions more explosive than others? Volcanic crystals are providing answers to these questions. This talk will examine new constraints on the precursors and dynamics of volcanic eruptions.

Programmable Quantum Materials

Thu May 16, 2024, 7:00PM ET

Dmitri Basov, Professor of Physics, Columbia University

The term “quantum technology” embodies the vast portfolio of phenomena in which quantum mechanics is manifest on the macroscopic scale. Developments now on the horizon include entirely novel information processing approaches enabling practical artificial intelligence, secure communication networks and entirely novel sensors. A broad consensus has emerged that quantum technology will have a disruptive impact on the economy and on society. The impact is likely to be on par with that of the first “quantum revolution” of the 1960s that resulted in such world-changing inventions as the laser (devised by Charles Townes at Columbia).

Among the many challenges in this vibrant area of research is the development of solid state materials capable of hosting quantum effects and on-demand programmable properties. I will discuss the current effort and progress in this line of research at Columbia.