Ultralight Boson Dark Matter and Event Horizon Telescope Observations of M87.

The initial data from the Event Horizon Telescope (EHT) on M87*, the supermassive black hole at the center of the M87 Galaxy, provide direct observational information on its mass, spin, and accretion disk properties. A combination of the EHT data and other constraints provides evidence that M87* has a mass ∼6.5×109 M⊙. EHT also inferred the dimensionless spin parameter |a*|≳0.5 from jet properties; a separate recent analysis using only the light from near M87* as measured by the EHT Collaboration found |a*|=0.9±0.1. These determinations disfavor ultralight bosons of mass μb∈(0.85,4.6)×10-21 eV for spin-one bosons and μb∈(2.9,4.6)×10-21 eV for spin-zero bosons, within the range considered for fuzzy dark matter, invoked to explain dark matter distribution on approximately kiloparsec scales. Future observations of M87* could be expected to strengthen our conclusions. [ABSTRACT FROM AUTHOR]