November 20, 2015
Work in particle physics and General Relativity (GR) has established that deep connections exist between acoustics and GR. Most remarkable is the fact that acoustic wave propagation in fluids is governed by an effective Lorentzian spacetime geometry: Acoustic waves follow the geodesics of a (curved) acoustic metric. This provides an entirely new way of looking at acoustic propagation, and in principle provides valuable theoretical tools since much of the machinery developed by the GR community over the past several decades can be directly applied to acoustic systems expressed in this framework. Notably, supersonic liquid flows are predicted to have completely analogous properties to spacetime regions near (gravitational) black holes. I will present the status of a research program at NRL designed to begin exploring these connections via laboratory experiments, numerical simulations, and theoretical development. [Work supported by the Office of Naval Research.]
David Goldstein received the Ph.D. degree in physics from the University of California, Los Angeles, CA, USA, in 2004, where his research involved measuring the properties of top quarks at the Fermi National Accelerator Laboratory. As a Postdoctoral Researcher with the Department of Physics at University of California, Irvine, during 2004–2008, he worked on the ANITA and ARIANNA experiments, which employ radio techniques to search for ultrahigh-energy neutrinos interacting in the Antarctic ice sheets and Ross ice shelf. Since 2008, he has been a Research Physicist with the Acoustics Division, Naval Research Laboratory, Washington, DC, USA, where he conducts basic research in the acoustics of supersonic liquid flows, solid-state physics, optical communications, and the coherence of underwater sound. Dr. Goldstein is a member of the Acoustical Society of America and the American Physical Society.