When Einstein developed his General Relativity theory,communicating and broadcasting devices using radio waves didn’t even exist yet. He could not possibly have imagined all of the instruments that scientists would use over the next century to put his theory to test,verify it and prove his predictions. The fact is that even Einstein was not sure about his predictions would one day proved experimentally because they are very difficult to experiment and the results would be of negligible measurements.
Recently a team of researchers confirmed one of the major Einstein’s predictions when they experimentally showed ,a star warping the light which comes a little near. The team lead by the scientist Kailash Sahu from the Space Telescope Science Institute, the resulting values and measurements shows the mass of the that star,along with a new method or scale that astronomers can use for better understanding of stars and galaxies. The research team demonstrated these results at the Meeting of the AAS and in a paper in the Science Journal.
The basic and fundamental idea of General Relativity is that,the mass warps spacetime.
What we feels as gravity is the consequence of this warping and the distortions created in spacetime. Although,Einstein believed most his ideas cannot be tested experimentally,as there was no technology and instruments for that,he suggested a method to prove the bending of light. Observing the bending of sunlight during an Eclipse,which Sir Arthur Eddington, an English scientist experimented during a solar eclipse on May 29, 1919 and proved the theory.
As per Einstein’s predictions, light from a distant source should observe to be bend as it comes from behind the sun ,as it is a massive body and curves space-time. The warping will cause the light from the distant source to appear from a different location than the original one.
Now,Sahu’s team made a Similar but much more perfect and sensitive measurement. With the Hubble Space Telescope, it might be possible to measure Same procedure,Which Eddington Did. Nobody have tried this before,as the results would be much more less. The predictable bending depends many factors such as, how the background source and nearby object align, the mass of the nearby object, and the relative distance between each object and the observer.
After a trial,with nearly 5000 stars at hand,The team set its eyes on Stein 2051 B, a white dwarf star nearly 18 light years away [A white dwarf is what stars like the Sun become after they have exhausted their nuclear fuel. Near the end of its nuclear burning stage, this type of star expels most of its outer material, creating a planetary nebula. Only the hot core of the star remains : NASA]
Our sun will become a white dwarf one day.
Using more advanced technology, perfection of instrumentation and greater precision, the scientists found and charted out the location of Stein 2051 B relative to background light sources,the other stars. Then they made use of Hubble to watch the star many times for almost two years. As it passed between us and a distant background light source. Stein 2051 B is nearly 400 times brighter than this distant star, so calculating the apparent location of the star during the eclipse of Stein 2051 B was a big stuff to control,a real challenge. They finalized it and the results agreed with Einstein’s General Relativity theory.
You may think,this was a big whole thing by a bunch of scientists to prove Einstein’s theory again and again. What a good time pass. But not!
The details of the experiment also provided important information on white dwarfs. The shift in the apparent position of a background star depends on the mass of the nearby object, the researchers Calculated the mass of the Stein 2051 B from their results and data obtained – 0.675 times the mass of our sun. Einstein have already predicted this method, but thought it would be almost impossible in reality. That’s what this group of Scientists cracked.
This mass determination is not a silly matter in this case of for Stein 2051 B. Its mass had been estimated previously using a less reliable method. But this research puts those questions to rest and shows that Stein 2051 B is just a normal, average-mass white dwarf. The mass determination also gave a remarkable prediction in the theory that describes, how the mass and radius of a white dwarf star is mutually related to each other.