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    I am an astronomer, cosmologist, and data scientist, currently a NSF funded Assistant Research Scientist at the UC San Diego Center for Astrophysics & Space Sciences (CASS) and a Research Affiliate in the MIT STS Program. I work on several theoretical and observational projects to devise and implement fun experiments that leverage cosmology to test fundamental physics, including novel tests of quantum theory using with astronomical observations, searches for exotic new physics with optical polarization studies of distant galaxies, as well as Infrared and Optical studies of Supernovae with ground and space based telescopes to measure the expansion history of the universe, cosmic acceleration, and dark energy. I enjoy exploring fascinating scientific questions at the intersection between observational astronomy, astrophysics, data analysis, and the philosophy of science through research, science writing, art, animation, public outreach, and science media engagement. For more, see my Bio, Resume, and CV.
Astroparticle Physics
   At UCSD CASS, I am leading a new Astroparticle Physics project with UCSD CASS Faculty, including Professors Brian Keating and David Tytler. We are collaborating with Astronomer Gary Cole, an expert in robotic polarimetry automation and instrumentation, to observe several AGN using a small telescope system maintained and operated by Cole.

   Astronomical observations of cosmological sources are increasing becoming useful tools to learn about new physics beyond the Standard-Model of Particle Physics, complementary to Earth-bound particle accelerators. One particular phenomenon that could manifest if fundamental symmetries like Lorentz Invariance and Charge-Parity-Time (CPT) symmetry are violated in the new physics, is called ``vacuum birefringence'', which could cause light from distant sources traveling over cosmological distances through empty space to have its polarization altered ever so slightly in a cumulative fashion as it travels to us. Polarization measurements of extragalactic sources, including astrophysical tests with optical polarization measurements of cosmological sources, including Active Galactic Nuclei (AGN), can therefore be used to place interesting and useful limits on such new physics. Lower energy optical polarization measurements, which are routinely done with ground-based telescopes, can play an important role in constraining effects like vacuum birefringence, in comparison to baloon-borne or space-based higher energy x-ray/gamma-ray polarization measurements of distant source like Gamma-ray bursts, which are much more difficult and expensive to perform.
Papers
Standard-Model Extension Constraints on Lorentz and CPT Violation From Optical Polarimetry of Active Galactic Nuclei, Friedman, A.S., Leon, D., Gerasimov, R., Crowley, K.D., Broudy, I. Melkani, Y., Stephens, W., Johnson, D., Teply, G., Tytler, D., Keating, B.G., and Cole, G.M. 2019, World Scientific Publishing, Proceedings of the Eighth Meeting on CPT and Lorentz Symmetry (CPT'19), Indiana University, Bloomington, May 12-16, 2019 (arXiv:1906.07301 | PDF)
Constraints on Lorentz Invariance and CPT Violation using Optical Photometry and Polarimetry of Active Galaxies BL Lacertae and S5 B0716+714, Friedman, A.S., Leon, D., Crowley, K.D., Johnson, D., Teply, G., Tytler, D., Keating, B.G., and Cole, G.M. 2019, Physical Review D, Vol. 99, Issue 3, id. 035045 (arXiv:1809.08356 | PDF) (DOI)
Talks
Constraints on Lorentz Invariance and CPT Violation using Optical Polarimetry of Active Galaxies, CPT'19: 8th Meeting on CPT and Lorentz Symmetry, University of Indiana, Bloomington, Physics Department (May 15 2019)

Constraints on Lorentz Invariance and CPT Violation using Optical Polarimetry of Active Galaxies, University of California, San Diego (UCSD), Center for Astrophysics and Space Sciences (CASS) (May 10 2019)

Gary M. Cole, APPOL and the Quest for Rho, University of California, San Diego (UCSD), Center for Astrophysics and Space Sciences (CASS) (Jun 3 2019)
Astronomer Gary Cole presents his telescope designs for MULTIPOL, an automated polarimetry system of small telescopes that can observe simultaneously in multiple optical bandpasses. The goal is to use polarimetric observations of distant galaxies to constrain potential new physics beyond the Standard-Model of Particle Physics. The project is coordinated via the Ax Center for Experimental Cosmology and the UCSD Cosmology group at the UCSD Center for Astrophysics and Space Sciences in collaboration with Professor Brian Keating and Assistant Research Scientist Andrew Friedman. A relevant recent paper by the collaboration used observations from an earlier version of Cole's robotic telescope system, the Array Photo Polarimeter (APPOL), which MULTIPOL is a recent upgrade to. APPOL observations were used for our recent paper, Constraints on Lorentz invariance and CPT violation using optical photometry and polarimetry of active galaxies BL Lacertae and S5 B0716+714, Andrew S. Friedman, David Leon, Kevin D. Crowley, Delwin Johnson, Grant Teply, David Tytler, Brian G. Keating, and Gary M. Cole, Physical Review D, 99, 035045 (2019). Also see a recent Conference Proceedings about the project, which was presented at the Eighth Meeting on CPT and Lorentz Symmetry (CPT'19), Indiana University, Bloomington (May 12-16, 2019).
University of California, San Diego UCSD Center for Astrophysics & Space Sciences Massachusetts Institute of Technology MIT Center for Theoretical Physics Institute for Quantum Optics and Quantum Information, Vienna Harvard University Astronomy Harvard-Smithsonian Center for Astrophysics UC Berkeley Astronomy National Science Foundation National Aernautics & Space Administration
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Last Updated: Andrew Samuel Friedman, 6/2017

University of California, San Diego, 9500 Gilman Drive
CASS, M/C 0424, SERF Bldg. 334, La Jolla, CA 92093-0424, USA (858) 534-5416


This material is based upon work supported by the National Science Foundation under NSF Award #1056580 (2012-2014) through an NSF Science, Technology, and Society Postdoctoral Fellowship at MIT and the NSF INSPIRE program via NSF Award #1541160 (2015-2019).

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