Einstein's Theory Of Relativity Still Works Even Under Extreme Conditions

Albert Einstein is proven right once more as scientists tackle the theory of general relativity — and take it to the stars.

The Theory Of General Relativity

Einstein's famous theory states that all objects fall at the same rate in the same gravitational field, provided there is no air resistance. For example, a bowling ball and a marble falling off the Leaning Tower of Pisa will hit the ground at the exact same time, regardless of the differences in mass and composition.

Until now, though, it hasn't been proven if the theory holds true in extreme gravity situations.

A Starry Experiment

In a new study published in the journal Nature, an international team of scientists focused on a triple star system 4,200 light-years away. This system consists of a neutron star (a pulsar) orbiting a white dwarf, and this pair in turn orbiting another white dwarf.

First, it's important to remember that objects in orbit are simply in free fall, getting pulled by gravity but never touching the surface since it is moving at the same rate as the object pulling it is curving. This is how a satellite orbits the Earth.

The Conversation explains that according to the theory of general relativity, the acceleration of the pulsar and the white dwarf should be the same as they free fall toward the other white dwarf. This is despite their differences in mass, composition, and self-gravity.

Over a six-year observation period, the researchers constructed models of the pair's orbits, trying to see if there's a difference between the two stars' behavior toward the third's gravitational pull.

They found negligible differences, demonstrating how Einstein's theory is still the best existing model of how gravity works.

"If there is a difference, it is no more than three parts in a million," coauthor Nina Gusinskaia, a PhD student at the University of Amsterdam, says in a statement to the University of British Columbia. "Now, anyone with an alternative theory of gravity has an even narrower range of possibilities that their theory has to fit into, in order to match what we have seen."

The Theory Thrives In Another Galaxy, Too

A separate study, published in the journal Science last June, reveals that the theory of general relativity is proven right in an analysis of a nearby galaxy.

One of the hallmarks of the theory is how large mass objects can warp space-time around it, including light, according to Gizmodo. In the study, the team was able to prove the accuracy of general relativity by measuring how much the galaxy ESO 325-G004 is warping the light that's passing around it.