Scientists were not entirely sure if electromagnetism is the same across the universe. However, in the recent experiment this notion has finally been brought to light.
Electromagnetism is one of the four forces of nature. It's other famous counterpart is the gravitational force. Then you have the weak force and strong force to complete the list.
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The only way to confirm if electromagnetism is indeed a constant is to be able to measure it.
Astronomers relied on the light from a quasar known as HE 0515-4414 from 8.5 billion years ago. Quasar is the compact ultra bright-light area around a black hole. It emits super massive energy that is defined by the mass of the core of its surrounding galaxy and its black hole's gravity. The quasar light passed through distant galaxies before finally reaching earth.
To understand how quasars work, astronomers have to measure how the distant galaxies absorb certain wavelengths of quasar light that passes through it. Since absorption by these galaxies are electromagnetic in nature. astronomers can study the changes in the spectrum of light as it reaches earth.
Srđan Kotuš of Swinburne University of Technology in Australia and who lead the study said, "The pattern of colors tells us how strong electromagnetism is in this galaxy, and because the quasar is one of the brightest ones known, we were able to make the most precise measurement so far."
Credit to Swineburne University (click to view Youtube video)
He added, "We found electromagnetism in this galaxy was the same as here on Earth within just one part per million – about the width of a human hair compared to the size of a sports stadium."
Now that we get that one cleared about electromagnetism as the same with the other galaxies as with earth's, we are still left with a question - why?
Michael Murphy, co-author of the study ended it off with the statement, "For me, finding that electromagnetism is constant over more than half the Universe’s age just deepens the mystery – why is it that way? We still don’t know. It’s remarkable that distant galaxies provide such a precise probe of such a fundamental question. With even larger telescopes now being built, we’ll be able to test it even better in the near future"
The study is published in Monthly Notices of the Royal Astronomical Society