The Arts and Humanities at the Event Horizon: Shep Doeleman on Photographing Black Holes
Date and Time
Location
CELESTIAL SPHERES
Speaker: Shep Doeleman, Harvard University / Smithsonian Astrophysical Observatory
Can you take a photograph of a black hole? What does it mean to have imaged an object whose nature is to remain unseen? Black holes are cosmic objects so small and dense that nothing, not even light, can escape their gravitational pull. Until recently, no one had ever seen what a black hole actually looked like. Einstein's theories predict that a distant observer should see a ring of light encircling the black hole, which forms when radiation emitted by infalling hot gas is lensed by the extreme gravity near the event horizon. The Event Horizon Telescope (EHT) is a global array of radio dishes, linked together by a network of atomic clocks to form an Earth-sized virtual telescope that can resolve the nearest supermassive black holes where this ring feature may be measured. The EHT has now successfully imaged the 6.5 billion solar mass black hole at the center of galaxy M87, and the 4 million solar mass black hole at the center of the Milky Way - both objects exhibiting the predicted strong gravitational lensing that confirms the theory of General Relativity at the boundary of a black hole. This talk will cover how this was accomplished, details of the first results, and future directions. Following the talk, Doeleman will be in conversation with seminar leader Jennifer L. Roberts about how astrophysicists and humanities scholars share approaches to the unknown and unknowable.