Albert Einstein's insights into gravity hold true even in one of the most extreme scenarios the universe can offer, according to a study.
Einstein's understanding of gravity, as outlined in his general theory of relativity, predicts that all objects fall at the same rate, regardless of their mass or composition.
This theory has passed test after test here on Earth, but scientists have wondered whether it still holds true for some of the most massive and dense objects in the known universe, an aspect of nature known as the Strong Equivalence Principle.
The new findings, published in the journal 'Nature', show that Einstein's insights into gravity still hold sway, even in one of the most extreme scenario.
To date, Einstein's equations have passed all tests, from careful laboratory studies to observations of planets in our solar system.
However, alternatives to Einstein's general theory of relativity predict that compact objects with extremely strong gravity, like neutron stars, fall a little differently than objects of lesser mass.
That difference, these alternate theories predict, would be due to a compact object's so-called gravitational binding energy - the gravitational energy that holds it together.