Gravitational Test beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole
No Thumbnail Available
Access rights
openAccess
publishedVersion
URL
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
Date
2020-10-01
Major/Subject
Mcode
Degree programme
Language
en
Pages
9
Series
Physical Review Letters, Volume 125, issue 14
Abstract
The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources.Description
Keywords
Other note
Citation
Event Horizon Telescope Collaboration 2020, ' Gravitational Test beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole ', Physical Review Letters, vol. 125, no. 14, 141104 . https://doi.org/10.1103/PhysRevLett.125.141104