Richard Anantua pictured above with Neil deGrasse Tyson, Bill Nye the Science Guy, Lisa Randall, Brian Greene and Ed Witten.
Postdoc 2 – Harvard-Smithsonian Center for Astrophysics 2019-22
I am a postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics (CfA) – Institute for Theory and Computation (ITC), fellow of the Black Hole Initiative (BHI) and member of the Event Horizon Telescope (EHT) Collaboration. My current research seeks to model emission near supermassive black holes in active galactic nuclei, linking general relativistic magnetohydrodynamic (GRMHD) simulations of ever-increasing dynamical range to astronomical observations of ever-increasing spatiotemporal resolution. In particular, I relate GRMHD variables to the astrophysical plasma physics of equipartition, turbulent heating, current density and velocity shear to generate postprocessed images, spectra and light curves in order to understand and predict multiwavelength observational signatures from Sgr A*, M87 and 3C 279— targets of the EHT. An example GRMHD movie with Sgr A* parameters is shown in Fig. 1.
Figure 1. Movie simulating emitting plasma near the event horizon of Sgr A*. The 4 million solar mass black hole lenses disk and outflow into photon rings and filaments in a turbulent heating model with electron temperature given by
Te/Tsim ≅ 0.5*exp[-(ug/3.0)/(b2/2.0)]
for total gas pressure ug and magnetic field strength b. Lengths and times are measured in a unit M relating to the scale of the black hole.
Postdoc 1 – UC Berkeley 2016-19
As a former high-energy astrophysics postdoctoral fellow in Prof. Eliot Quataert’s group at UC Berkeley, I modeled emission from Sagittarius A* at the Galactic Center. The methodology I developed for “observing” jet (or outflow)/accretion disk/black hole (JAB) simulations directly relates emission to phenomenological processes involving electron heating, equipartition, shear and current density. For example, JAB simulations revealing plasma behavior such as the decreasing of electron temperature with the ratio β of gas-to-magnetic pressure inform semi-analytic calculations of images, as seen in Fig. 2.
Figure 2. Images of an inner accretion disk and polar outflow for electron temperature model
Te/Tsim ≅ f*exp[-((ug/3.0)/(b2/2.0))/βc]
An overall prefactor f in electron-to-ion temperature ratio increases from top to bottom rows and a critical value of β increases from left to right. Intensity (in janskys) is logarithmically scaled.
I also “observed” simulations of relativistic jets– a continuation of my PhD work across the SF Bay at Stanford under Prof. Roger Blandford.
Grad School – Stanford 2011-16
My first year as a graduate student at Stanford featured a combination of coursework and research providing a working knowledge of modern approaches to quantum gravity. Upon gaining background in renormalization and conformal field theory from Quantum Field Theory I, II and III and rotating under Leonard Susskind, Shamit Kachru and Sean Hartnoll of the Stanford Institute for Theoretical Physics (SITP), I focused on using the holographic correspondence to determine whether a Fermi surface (or similar phenomena) exist in strongly coupled field theories with supersymmetry. With Martin et al., I used gauge-gravity duality to find current-current correlators and the associated spectral weight for a superconformal field theory dual to a D3-D5 brane system in the background of type IIB string theory (see Publications).
During my second year, my focus shifted to theoretical physics at lower energy scales relevant to observations. I joined the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) under adviser Roger Blandford (Fellow of the Royal Society and National Academy of Sciences).
Since returning from Harvard to start the third year of my doctorate, I started working towards rendering the output of 3D general relativistic magnetohydrodynamic simulations (e.g., from Jonathan McKinney) of jets from black holes with accretion flows in a manner that mimics or surpasses image resolution from existing or planned astrophysical surveys (e.g., Event Horizon Telescope).
My broad research interests have included: theoretical cosmology, high-energy theoretical astrophysics (e.g., Blandford-Znajek jets from supermassive black holes), high-energy theoretical particle physics (e.g., string theory (esp. AdS/CFT correspondence)), condensed matter theory (e.g., strongly correlated fermionic systems with holographic dual)