A new theory of gravity passed it’s first major test this week. Professor Erik Verlinde, a specialist in string theory at the University of Amsterdam and the Delta Institute for Theoretical Physics, has developed a new theory of gravity that could replace aspects of Albert Einstein’s general theory of relativity and change our understanding of dark matter.
Verlinde first introduced his controversial new theory back in 2010. This week, a team of physicists led by astronomer Margot Brouwer of the Leiden Observatory in the Netherlands concluded that Verlinde’s theory appears to accurately account for the disproportionately strong gravitational lenses created by massive objects such as galaxy clusters. Einstein’s theory fails to fully explain this phenomenon.
“While general relativity says a strong source of gravity — like the sun — will warp the fabric of space, bend light from a distant object, and magnify it to an observer, very big objects like galaxies and galaxy clusters make gravitational lenses that are theoretically too strong,” a new Phys.org article explains. “General relativity also can’t fully explain the spinning motions of galaxies and their stars.”
Verlinde’s 2010 paper, in which he first introduced his ideas, “surprised the world with a completely new theory of gravity,” according to an earlier Phys.org report from November.
“The outer regions of galaxies, like our own Milky Way, rotate much faster around the center than can be accounted for by the quantity of ordinary matter like stars, planets and interstellar gasses,” according to Phys.org. “Something else has to produce the required amount of gravitational force, so physicists proposed the existence of dark matter.”
Popular at EarthSky… 1st test of new theory of gravity https://t.co/XFLZ9LTCY0
An alternative to Einstein’s theory… pic.twitter.com/0CrISiCtLV
— EarthSky (@earthskyscience) December 18, 2016
Some physicists estimate that up to 80 percent of the universe is comprised of dark matter, which would make it by far the most dominant form of matter in the universe. However, dark matter particles have never been observed or proven to exist by any of the research attempting to verify their presence.
Erik Verlinde argues that his theory answers the questions of unexplainably strong gravitational lenses and the disproportionate acceleration of the outer regions of galaxies without having to rely on the presumption of dark matter.
“According to Verlinde, gravity is not a fundamental force of nature, but an emergent phenomenon. In the same way that temperature arises from the movement of microscopic particles, gravity emerges from the changes of fundamental bits of information, stored in the very structure of spacetime,” the Phys.org report from November reads. “In his 2010 article (On the origin of gravity and the laws of Newton), Verlinde showed how Newton’s famous second law, which describes how apples fall from trees and satellites stay in orbit, can be derived from these underlying microscopic building blocks. Extending his previous work and work done by others, Verlinde now shows how to understand the curious behaviour of stars in galaxies without adding the puzzling dark matter.”
Business Insider‘s Dave Mosher suggests that this provides a much simpler explanation of gravity than the one we currently rely on.
“Put another way, gravity may just be nature trying to fill a void with chaos, much like air rushing to fill a vacuum, or the heat of your body escaping into the space around you — no exotic, invisible, force-carrying particles required,” Mosher says.
Brouwer and her team tested Verlinde’s theory of gravity by measuring the the gravity surrounding more than 33,000 galaxies. They concluded that the new theory “agrees well” with the distribution of gravity around those galaxies. The results of their research will be published in the British journal Monthly Notices of the Royal Astronomical Society.
“The question now is how the theory develops, and how it can be further tested. But the result of this first test definitely looks interesting,” Brouwer said.
— Business Insider (@businessinsider) December 17, 2016
Verlinde is quick to distinguish his theory of gravity from Modified Newtonian Dynamics (MOND) and other modified theories of gravity. He argues that MOND simply adjusts observations to correspond to general relativity, whereas he approaches gravity from “a totally different starting point.”
Indeed, Verlinde’s theory does rise from a somewhat different foundation than Einstein’s.
“One of the ingredients in Verlinde’s theory is an adaptation of the holographic principle, introduced by his tutor Gerard ‘t Hooft (Nobel Prize 1999, Utrecht University) and Leonard Susskind (Stanford University),” Phys.org explains. “According to the holographic principle, all the information in the entire universe can be described on a giant imaginary sphere around it. Verlinde now shows that this idea is not quite correct—part of the information in our universe is contained in space itself.”
Verlinde is convinced his new theory of gravity fills in some of the gaps in Einstein’s theory.
“We have evidence that this new view of gravity actually agrees with the observations, ” says Verlinde. “At large scales, it seems, gravity just doesn’t behave the way Einstein’s theory predicts.”
[Featured Image by NASA/Getty Images]