(CN) — European scientists who tested Albert Einstein’s theory of general relativity on the supermassive black hole at the center of the Milky Way galaxy suspect, once again, that Einstein was right: that gravity bends space.
Einstein’s theory suggests that large objects bend the space around them, causing other objects to diverge from the straight lines they would otherwise follow. While previous studies have validate d his theory, it had not been tested on such a gigantic object.
Using data collected by telescopes around the world from the past 20 years, the team analyzed the movements of three stars near Sagittarius A*, a black hole about 4 million times as massive as the sun.
The analysis revealed minor deviations in the orbit of one of the stars, called S2, which may indicate relativistic effects, the team said. If the observations are confirmed, they will show that Einstein’s theory of general relativity applies even under extreme conditions: the strong gravitational field of Sagittarius A*.
The article in the Astrophysical Journal was written by scientists from the Physics Institute in the University of Köln, the Max Planck Institute for Radioastronomy, and the Astronomical Institute at the Academy of Science in Prague.
Most relativity tests have been performed on the sun and nearby stars, which are around one solar mass to a few solar masses, a standard unit of measurement in astronomy equivalent to the mass of the sun. The Laser Interferometer Gravitational-Wave Observatory (LIGO) has also been used recently to test cosmic objects that are a few dozen solar masses: a fraction of the size of Sagittarius A*.
The team applied a novel approach to observational data of the stars, which involved comparing the actual measurements of the cosmic bodies’ orbits to those predicted by both Newtonian gravity, established by Sir Isaac Newton in the 17th century, and general relativity.
The scientists noted that the measurements they analyzed could be more precise. The team hopes that future research can better quantify the stars’ positions. This might be accomplished using better spectrographic measurements, which could track S2’s movements more closely.
Einstein wondered how gravity could work, apparently instantaneously, over immense distances, though according to his theories nothing could move faster than the speed of light. Imagining the universe as a giant sheet with a bowling ball in the center, he saw that a straight line on the sheet would bend; and projecting into three, or four, dimensions, saw that gravity could bend space.