Facility for Rare Isotope Beams

Massive stars are important metal factories in the Universe because through their winds and explosive deaths as supernovae they provide radiative, kinematic, and chemical feedback to their surroundings. However, stellar evolution models currently contain large theoretical uncertainties for physical mechanisms at work in the deep interiors of massive stars. The uncertainties associated with rotation, chemical mixing, magnetic fields, and angular momentum transport propagate throughout stellar evolution making it difficult to accurately determine stellar masses and ages. The analysis of pulsation frequencies in massive stars allows one to break model degeneracies, uniquely probe stellar interiors, and constrain uncalibrated physical processes within our models. In this seminar, I discuss the recent advances in our understanding of massive stars by means of asteroseismology – the study of stellar pulsations. Modern space telescopes have revealed diverse variability mechanisms in massive stars across different evolutionary stages, which includes the main sequence through to blue supergiant stars. This provides us with the opportunity to perform a data-driven calibration of evolution models for some of the most massive and short-lived stars in the Universe.

Quantum entanglement represents a classically forbidden form of correlation shared between separate local subsystems. The atomic nucleus serves as an ideal platform for exploring quantum entanglement at subatomic scales. A key characteristic of quantum entanglement is its scaling behavior with respect to subsystem size. Motivated by a recent study [Gu et al., Phys. Rev. C 108, 054309 (2023)], I investigate the scaling behavior of orbital entanglement in nuclear shell model. The results show that the average orbital entanglement entropy follows a Page-like curve, consistent with volume law scaling, for both ground and excited states. This finding suggests the absence of an entanglement crossover from area law to volume law in the nuclear shell model, distinguishing it from typical condensed matter systems. Additionally, the influence of angular momentum conservation on orbital entanglement is examined.

TBD

Life on Earth is wonderfully diverse, with a multitude of life forms, structures and evolutionary mechanisms. However, there are two aspects of life that are universal - shared by all known organisms. These are the genetic code, which governs how DNA is converted into the proteins making up your body, and the unexpected left-handedness of the amino acids in your body. One would expect that your amino acids were a mixture of left and right-handed molecules, but none are right handed! In this talk, I describe how these universal aspects of biology can be understood as arising from evolution, but generalized to an era where genes, species and individuality had not yet emerged. I will also discuss to what extent one can find general principles of biology that can apply to all life in the universe, and what this would mean for the nascent field of astrobiology. Prof. Nigel Goldenfeld holds the Chancellor's Distinguished Professorship in Physics and joined UCSD in Fall 2021 after 36 years at the University of Illinois at Urbana-Champaign (UIUC). His research spans condensed matter theory, the theory of living systems, hydrodynamics and non-equilibrium statistical physics. He received his Ph.D in theoretical physics from the University of Cambridge (UK) in 1982, and for the years 1982-1985 was a postdoctoral fellow at the Institute for Theoretical Physics, University of California at Santa Barbara, where his work on the dynamics of snowflake growth helped launch the modern theory of pattern formation in nature. He joined the condensed matter theory group at the Department of Physics, UIUC in 1985, where his work was instrumental to the discovery of d-wave pairing in high temperature superconductors. In 1996, he co-founded NumeriX, a company that develops high-performance software for pricing and risk managing derivative securities. His interests in biology include microbial ecology, evolution and systems biology. He was a founding member of the Institute for Genomic Biology at UIUC, where he led the Biocomplexity Group and directed the NASA Astrobiology Institute for Universal Biology. During the COVID-19 pandemic, he pivoted from his experience in mathematical modeling of bacteria and viruses to computational epidemiology, advising the Governor of Illinois, and helping devise, set up and run the COVID saliva testing system at UIUC, which provided ~12 hour turnaround of PCR tests to the 50,000 people in the campus community and eventually to over 1700 schools and other institutions in Illinois and beyond. He has served on the editorial boards of several journals, including The Philosophical Transactions of the Royal Society, Physical Biology and the International Journal of Theoretical and Applied Finance. Selected honours include: Alfred P. Sloan Foundation Fellow, University Scholar of the University of Illinois, the Xerox Award for research, the A. Nordsieck award for excellence in graduate teaching and the American Physical Society's Leo P. Kadanoff Prize 2020. He is a Fellow of the American Physical Society, a Fellow of the American Academy of Arts and Sciences, a Fellow of the Royal Society (UK) and a Member of the US National Academy of Sciences.