The dark matter could be a myth

A galaxy needs to contain a specific mass in order for gravity to hold it together, according to general relativity theory. Nevertheless, gravity maintains many galaxies in the universe intact even though scientists are unable to detect enough visible mass in them. What makes this possible at all?

This is where the idea of dark matter becomes relevant. According to scientific theory, invisible mass exists in galaxies in the form of matter that is inert to light. This invisible mass is the reason for the gravity that holds these galaxies together.

This rationale has been used for decades to bolster the case for the possibility of dark matter. But a recent study suggests that gravity can exist independently of mass, which could mean that dark matter is not necessary at all.

Richard Lieu, the study’s author and a distinguished professor of physics and astronomy at the University of Alabama in Huntsville (UAH), stated that his enthusiasm for this novel theory is motivated by his dissatisfaction with the status quo, specifically the idea that dark matter exists despite the lack of any direct evidence for a century.

Gravity can also originate from topological defects.

According to Lieu, “shell-like topological defects” may be the source of the gravity required to hold some galaxies or clusters together. “.

Topological defects are distinctive, highly densely packed structures in space.

Phase transition, an occurrence in which matter undergoes a significant physical change throughout the universe, is most likely when these defects initially appeared in the early universe.

The defects in question may manifest as either flat, shell-like structures or as long, linear formations known as cosmic strings.

“The shells in my paper are made up of a thin, positive-mass inner layer and a thin, negative-mass outer layer. The total mass of both layers is exactly zero, as far as mass measurements go, but when a star is lying on this shell, it feels a strong gravitational pull toward the center of the shell,” Lieu said.

It is comparable to the way that photons, which are massless particles, nevertheless feel gravity as a result of large astronomical objects. This is due to the fact that gravity interacts with everything inside the curvature, regardless of mass, when it warps space and time.

the dark matter illusion.

Light bends as it travels along the spacetime curvature through massive astronomical objects rather than traveling straight through them. This phenomenon is known as gravitational bending, and it provides circumstantial evidence for the existence of mass and the general relativity-described effects of gravity on an object.

Until recently, scientists assumed that the invisible dark matter was responsible for any gravitational bending they observed in galaxy or galactic cluster cases where no visible mass was present.

Lieu, however, contends that the invisible mass of the galaxies and clusters is actually made up of a number of shell-like topological defects. Light is slightly drawn inward toward the center of these structures as it travels through each shell.

A discernible bend results from light passing through several shells, which is comparable to the effect of a significant amount of dark matter, much as dark matter appears to have an impact on the orbital velocity of stars.

The present study, however, rules out the existence of dark matter and concludes that the topological defects are the only cause of the gravitational bending.

According to Lieu, “it is currently unclear what precise form of phase transition in the universe could give rise to topological defects of this sort.”.

The present theory is the first indication that gravity can exist without mass, he continued, but it is “not by itself sufficient to discredit the dark matter hypothesis—it could be an interesting mathematical exercise at best.”.

The research has been published in the Royal Astronomical Society’s Monthly Notices journal.