Gravitational waves that move the cosmic fabric, known as spacetime, are now a reality verified by the Laser Interferometer Gravitational-Wave Observatory (LIGO). But until 2015, they were only a hypothetical part of Albert Einstein’s Theory of Relativity and had, in fact, been called into question. But now that LIGO has once again proved the German physicist right; scientists are using these kinds of ripples to learn about the beginnings of the universe.
What Are Gravitational Waves?
Albert Einstein revolutionized physics forever with the introduction of the concept of ‘spacetime,’ which is a fabric that permeates the universe and through which light travels. It warps and bends due to the gravitational fields of the bodies that inhabit it, so the physicist believed that it experiences ripples from massive events in the cosmos that propagate through spacetime.
Einstein himself believed that these kinds of movements resulting from large collisions in the cosmos were so imperceptible that we would never be able to detect them. But that changed in 2015 when LIGO was able to detect the ripples in space-time, proving the existence of gravitational waves.
A Glimpse into the Cosmic Past
Knowing about the origin of the universe has represented a real puzzle for cosmologists since it is impossible to look directly into a primitive cosmos and know what conditions were like at the beginning. This is why other means have been sought to learn about the evolution of the universe, and gravitational waves could help in the process.
“We can’t see the early universe directly, but we may be able to see it indirectly by looking at how the gravitational waves of that time have affected the matter and radiation we can observe today,” explains Deepen Garg, lead author of the paper published in the Journal of Cosmology and Astroparticle Physics. Garg is a graduate student in the U.S. Department of Energy’s Princeton Program in Plasma Physics.
[Photo: Rezoalla, L. Koppitz, M.]
How Are Fusion Energy and Gravitational Waves Similar?
Garg and his advisor, Ilya Dodin, found a way to adapt the technique of fusion energy research to gravitational waves. Nuclear fusion is the energy that powers stars and that scientists are using in state-of-the-art reactors to obtain exorbitant amounts of energy without radioactive contamination and carbon emissions.
Nuclear physicists calculate how electromagnetic waves move through plasma, the electron soup, and atomic nuclei that power fusion reactors known as tokamaks and stellarators. And strangely this process resembles the movement of gravitational waves through spacetime and matter. So Garg and Dodin used the nuclear fusion measurement to cosmic ripples. “Basically, we put the plasma wave machinery to work on a gravitational wave problem,” Garg said.
More measurements remain to be analyzed shortly to obtain significant results; however, the research is pioneering in its field and has opened a window into the past of the Universe using gravitational waves as evidence of a young cosmos.
Story originally published in Spanish in Ecoosfera
