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Could gravity exist without mass, thus reducing the need for the hypothetical dark matter

Scientists claim that circular systems of topological defects in the structures common throughout the universe may be the source of the "excess" gravity needed to hold a galaxy or cluster together

An illustration of gravity. Illustration: depositphotos.com
An illustration of gravity. Illustration: depositphotos.com


According to general relativity, dark matter, a hypothetical type of matter, cannot be explained unless there is a greater amount of matter in the universe than we see.
The dark matter hypothesis was first proposed by the Dutch astronomer Jan Ort in 1932, and was created to explain the so-called "missing mass" needed to form galaxies. This theory has not been fully explained almost since it was created.

Researchers at the University of Alabama at Huntsville (UAH) have shown for the first time how gravity can exist without mass, and offer an alternative explanation that could reduce the theoretical need for dark matter.

The scientists drew inspiration from a search for an alternative solution to the gravitational field equations of general relativity. This alternative solution, known as the Poisson equation, provides a finite gravitational force in the absence of any detectable mass and is applied to the state of galaxies and galaxy clusters.

Dr. Richard Liu, professor of physics and astronomy at UAH, part of the University of Alabama system, notes that "this initiative stems from my frustration with the current situation, namely the idea of ​​the existence of dark matter despite the lack of any direct evidence for a whole century."

The scientists claim that circular systems of topological defects in the structures common throughout the universe may be the source of the "excess" gravity needed to hold a galaxy or cluster together. These defects were probably created during the evolution of the early universe when a cosmological phase transition occurred, a physical process in which a state The general matter changes simultaneously throughout the universe.

Liu adds, "It is currently unclear what exact type of phase transition in the universe could give rise to these types of topological defects. Topological effects are very compact regions of space with a very high density of matter, usually in the form of linear structures known as cosmic threads, although two-dimensional structures such as spherical shells are also possible."

"The shells in my article consist of a thin inner layer of positive mass and a thin outer layer of negative mass; The total mass of the two layers is exactly zero, but when a star is on this shell, it experiences a strong gravitational force pulling it toward the center of the shell."

Gravity allows all objects, massless or massed, to interact with each other, because it fundamentally includes the distortion of space-time itself. For example, astronomical objects have been shown to exert a gravitational force on massless photons.

"Gravitational bending of light by a system of circular shells that make up a galaxy or cluster results from a light beam being deflected slightly inward—that is, toward the center of the large-scale structure, or system of shells—as it passes through one shell," Liu notes.

"The overall effect of passing through many shells is a finite and measurable shift that mimics the presence of a large amount of dark matter that similarly affects the speed of stars in their orbits."

"The bending of light and the speed of the stars' orbits are the only means by which it is possible to estimate the strength of the gravitational field in a large-scale structure, whether it is a galaxy or a cluster of galaxies. My paper claims that at least the shells it suggests are massless. There is no need to continue the seemingly endless search for dark matter.”

"Questions for future research will probably focus on how a galaxy or cluster was formed by aligning these shells, as well as how the development of the structures occurs" concludes Liu.

for the scientific article

More of the topic in Hayadan:

8 תגובות

  1. Yehuda
    What is the different source of these two forces?
    And if this source is so weak that we cannot discover it - then how is the idea scientific (as you say)?

  2. According to the theory of general relativity, gravitation is actually an expression of the geometrical properties of space and in particular its curvature. A model in which there is a contribution to the curvature of space that is not a result of the presence of mass, could perhaps explain the observed phenomena that led to the conception of the dark mass in the first place. Such a mechanism is actually already known and is described in the Casimir effect where it is possible to measure a force of attraction between close parallel plates that is not caused by a valve but by the difference in energy density between the plates compared to their outer side. It is interesting whether the existing differences in energy density across galaxies can explain the observed increase in the curvature of space in those regions.

  3. The key phrase in this article: "may be".
    For 50 years they say may be. When there will be a toast, meanwhile cosmology is in crisis.

  4. Another strange idea, there is another mass in the world that carries the force of gravity and light...epola

  5. Every article used to have a very interesting discussion in the comments.
    But today the responses are buried in an endless tangle of never-ending advertisements. just sad

  6. The main (scientific) mistake in this article is regarding gravitation as the force that activates most of the sources of rotation in the cosmos.
    There is no reason why gravitation, which is responsible for the rotation of the planets around the sun, at a distance of several tens of astronomical units, about a thousand light years, should also be the reason for the rotation of the entire galaxy, (thousands, or millions of light years)!!!!!

    For example, solution options,
    The existence of two different forces:-

    A. A force acting inversely proportional to the square of the distance (approximately) in the case of the planets - for example, gravitation,
    B. A force acting inversely proportional to the distance (approximately), in the case of the rotation of the galaxies.
    Without the need for dark matter, and dark energy.

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