© 2024
Local NPR for the Cape, Coast & Islands 90.1 91.1 94.3
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

Chameleon Theory Challenges Einstein's Ideas About Gravity

A new theory of gravity has been shown to form spiral-shaped galaxies in a computer simulation. This image is the night sky above Paranal taken by astronomer Yuri Beletsky in 2007. The laser points to the galactic center of the Milky Way galaxy.
Yuri Beletsky, https://tinyurl.com/y6nnetk6
A new theory of gravity has been shown to form spiral-shaped galaxies in a computer simulation. This image is the night sky above Paranal taken by astronomer Yuri Beletsky in 2007. The laser points to the galactic center of the Milky Way galaxy.

Einstein's theory of general relativity was revolutionary when it was introduced. Over the past century, aspects of the theory have been proven in experiment after experiment and much of it has become an assumed underpinning of daily life, even for non-scientists.

Take Einstein’s description of gravity.

Gravity is gravity, right? How strong it is depends on the mass of the objects involved. Or maybe not.

Scientists have been struggling to account for the majority of mass and energy in the universe. Decades of searching have so far failed to turn up a new particle to fill the void of so-called dark matter.

A new idea called chameleon theory takes a different approach.

“In chameleon theory, the strength of gravity changes both over time and within space,” Christian Arnold told Living Lab Radio. Arnold is physicist at Durham University in England who has been developing the theory.

In a less-dense region of the universe, say, a cosmic void, the forces described in chameleon theory are stronger compared to those described by general relativity. Meanwhile, in our solar system, the forces in chameleon theory work the same way as they do in general relativity.

“So, in this way, the theory changes its behavior or its color like a chameleon,” Arnold said.

Arnold and his colleagues ran supercomputer simulations of the evolution of the universe to test if realistic galaxies could form using chameleon theory. It worked.

“What we found was that galaxies like our Milky Way—so spiral galaxies, the spiral arms and a disk like shape in the stellar structure—can actually form,” he said.

Does that mean Einstein was wrong?

“It's very possible that we find out in a couple of years our theory is actually wrong and Einstein's works much better,” Arnold said.

“But I think, as a physicist, you have to constantly keep challenging theories and ideas and think in new ways. Otherwise you won't make any progress.”

--

Web content produced by Elsa Partan.

Stay Connected
Elsa Partan is a producer and newscaster with CAI. She first came to the station in 2002 as an intern and fell in love with radio. She is a graduate of Bryn Mawr College and the Columbia University Graduate School of Journalism. From 2006 to 2009, she covered the state of Wyoming for the NPR member station Wyoming Public Media in Laramie. She was a newspaper reporter at The Mashpee Enterprise from 2010 to 2013. She lives in Falmouth with her husband and two daughters.