Einstein's Theory holds up on extreme gravity test
New Delhi : Galileo, the father of modern science once concluded hundreds of years ago that all objects released together fall at the same rate, regardless of mass. Even Einstein’s theory of relativity proves that our planet Earth and the heavenly Moon “fall” in the same way toward the Sun as they orbit each other. But does this principle hold true for objects with extreme gravity?
An international team of astronomers experimented with this question by studying three stars orbiting each other about 4,200 light years from Earth.
The findings gave approval to the aforesaid theory and the paper is published by the journal Nature
Test subject PSR J0337+1715 is a triple star system, with one neutron star in a 1.6-day orbit with a white dwarf, both of which are in a 327-day orbit with another, more distant white dwarf.
Small and dense, the white dwarf is, well, dwarfed in substantiality by the neutron star, the smallest and densest of the celestial bodies. A pulsar, the neutron star emits radio waves measurable on Earth.
“It rotates 366 times per second, and beams of radio waves rotate along,” Anne Archibald, the paper’s first author at the Netherlands Institute for Radio Astronomy (ASTRON) and the University of Amsterdam.
“They sweep over the Earth at regular intervals, like a cosmic lighthouse,” she explained. “We have used these radio pulses to track the position of the neutron star.”
Astronomers said that they followed the neutron star for six years, tracking it via the Westerbork Synthesis Radio Telescope in the Netherlands, the Green Bank Telescope in West Virginia, and the Arecibo Observatory in Puerto Rico. They found that something is making the pulsar move.
And if, Einstein theory is to be believed, “it has to be the gravity of the white dwarf it’s circling,” according to David Kaplan, an associate professor of physics at the University of Wisconsin-Milwaukee and a co-author on the paper.
Also, if the neutron star fell differently from the white dwarf, researchers would have found a tremble in their measurements. But they didn’t.
“We’ve done better with this system than previous tests by a factor of 10,” Kaplan said in a statement. “But it’s not an ironclad answer. Reconciling gravity with quantum mechanics is still unresolved.”
Scientists believe that there is a long way to go. They are forever trying to understand how the universe works. Fortunately, the advancements in radio telescopes assure more chances at finding the “perfect” triple system to test.
“Among these yet undiscovered systems may lurk even more powerful tools for understanding the universe,” Jason Hessels, an associate professor at ASTRON and the University of Amsterdam, suggested. “Perhaps one of these may provide our first peek at a theory beyond Einstein’s.”
Albert Einstein’s idea of gravitational microlensing was first proven in 1919, when astronomers observed background stars were displaced by the eclipsed sun. And, later after 100 years, his theory of relativity has been confirmed, again.
