Agenda:
7:00 - 7:15 General Meeting & Announcements 7:15 - 7:30 Short topic presentation by a club member
7:30 - 7:45 Refreshment break
7:45 - Public Presentation
Speaker: Dr. Zachary Slepian - UF
Title: How Does the Universe Look in the Mirror?
Abstract:
Nature has a few fundamental symmetries, one of which is mirror symmetry (except for neutrinos). But is that really so? I will outline how we can use sets of four galaxies at a time, which form tetrahedrons, to probe whether the Universe looks the same in the mirror. I will show how this can be done with million to ten-million galaxy datasets such as that from Sloan Digital Sky Survey (SDSS) and Dark Energy Spectroscopic Instrument (DESI), and present recent results by my group that argue the Universe may not be so symmetric in the mirror, at high significance! I will discuss the implications of this—-new physics during the very earliest moments of the Universe (inflation), and maybe an explanation for why there is something rather than nothing (baryogenesis).
About the Speaker:
Originally from Fairfield, Connecticut, an early interest in philosophy led to his current interest in cosmology. He attended public high school, received a BA summa cum laude from Princeton (2011), working with J. Richard Gott, III on his senior thesis, an MSt in philosophy of physics at Oxford (2012), and a PhD in Astrophysics (2016) from Harvard, advised by Daniel J. Eisenstein. During his PhD, he focused on Baryon Acoustic Oscillations (BAO) in the 2-point and 3-point correlation function (3PCF) of galaxies, constraining a possible systematic sourced by high-redshift baryon-dark matter relative velocities using the 3PCF. This entailed developing a transformatively fast 3PCF algorithm, enabling the first high-significance detection of BAO in the 3PCF and a measurement of the cosmic distance scale six billion years ago to percent precision. Post-PhD, he spent one year as a Chamberlain Fellow and one year as an Einstein Fellow at Lawrence Berkeley National Laboratory, where highlights included an implementation of the 3PCF algorithm capable of computing the 3PCF for the entire observable Universe in 20-hours on NERSC’s Cori supercomputer, application of the 3PCF to MHD turbulence, and novel analytic solutions for the Friedmann equation in the presence of neutrinos or warm dark matter.
Research Interests:
Dark energy, dark matter, structure formation, large surveys, analytic methods, star formation. His current research follows three broad paths: creating theoretical models for large-scale structure, designing fast algorithms to measure it, and applying them to datasets such as BOSS, eBOSS, and DESI. Cutting across these areas are a strong attraction to analytic methods and excitement about effective use of high-performance computing.
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Member's Corner Speaker: Dean Covey
Topic: Observing the Universe with a 20-Meter Telescope
Speaker: Jessica Li - UF Astronomy
Title: UV Emissions Surrounding Galaxies
The circumgalactic medium (CGM) and intergalactic medium (IGM), the tenuous gas surrounding galaxies represent a significant portion of matter in the universe as indicated by both theoretical and observational studies. This faint and diffuse gas is not well studied since it is very challenging to observe. Studying the CGM is essential for understanding astrophysical principles that govern the formation and evolution of stars and galaxies throughout the universe. It is believed to be the reservoir of gas and material that is both the source and regulator of star-forming fuel, controlling the exchange between the intergalactic medium (IGM) between galaxies and interstellar medium (ISM) within galaxies. We advance our understanding of these processes through ultraviolet (UV) spectroscopic CGM emission line observations in high redshift galaxies in addition to instrumentation work for balloon-borne and space telescopes that target low redshift galaxies. I present four distinct but interrelated projects that combine observational astronomy, instrument building, and technology development. This includes quasar observations from the Palomar Cosmic Web Imager (PCWI), instrument work on FIREBall-2 (Faint Intergalactic-medium Redshifted Balloon) telescope and Aspera SmallSat mission, and technology development of UV reflective gratings.
Jess received her B.Eng. with a triple major in physics, astronomy, and mechanical engineering in 2015, and her M.S. in mechanical engineering in 2016 from Stony Brook University. At Brookhaven National Laboratory, she worked as a mechanical design engineer for the Large Synoptic Survey Telescope, Deep Underground Neutrino Experiment, and the Short Baseline Near Detector. Jess graduated with a Ph.D. in Physics and worked on a combination of UV astrophysics and instrumentation. Her thesis projects included: 1) analyzing Palomar Cosmic Web Imager data to understand the circumgalactic medium around quasars, 2) developing the Faint Intergalactic Medium Redshifted Balloon Telescope calibration system, 3) working on the Aspera SmallSat mission's grating characterization testing, and 4) measuring novel small-scale gratings manufactured with electron beam lithography for technology development in UV spectroscopy (collaboration with UIowa). She is continuing to work in UV astrophysics and instrumentation here as a postdoc with Keri Hoadley.
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Member's Corner Speaker: Warren Schmitt
Topic: My Work with Skylab
7:00 - 7:15 General Meeting & Announcements 7:15 - 7:30 Members Corner:
Speaker: James Albury, Planetarium Director and host of the YouTube Series "The Sky Above Us"
Topic: TBD
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Member's Corner Speaker: Rich Russin
Topic: H.H. Ninninger, Master of Meteorites
