New Answer to Cosmic Acceleration Challenges Dark Vitality Paradigm

Physicists from the Center of Applied Space Technology and Microgravity on the University of Bremen and the Transylvanian University of Brașov have unveiled a brand new theoretical framework that might rewrite how we perceive the accelerating growth of the Universe — and doubtlessly render the mysterious darkish power out of date. They’ve proposed that the acceleration could also be a basic function of spacetime geometry itself, moderately than the product of an unknown cosmic power.

This artist’s impression reveals the evolution of the Universe starting with the Big Bang on the left adopted by the looks of the Cosmic Microwave Background. The formation of the primary stars ends the cosmic darkish ages, adopted by the formation of galaxies. Image credit score: M. Weiss / Harvard-Smithsonian Center for Astrophysics.

For greater than a quarter-century, scientists have grappled with a startling remark: fairly opposite to expectations, the growth of the Universe is just not slowing below gravity’s pull however rushing up.

In the Nineteen Nineties, astronomers inferred this acceleration by observing distant Type Ia supernovae, a discovery that led to the widespread postulation of darkish power — a pervasive, unseen element thought to drive cosmic acceleration.

Yet regardless of its central function within the Standard Model, darkish power’s bodily nature stays elusive.

In their new work, Dr. Christian Pfeifer and his colleagues argue that the growth of the Universe may very well be defined, at the very least partly, by modifying the underlying geometric framework used to explain gravity.

At the center of contemporary cosmology lies Einstein’s basic principle of relativity, which describes how matter and power form spacetime.

The evolution of the Universe itself is modeled utilizing the Friedmann equations, derived from Einstein’s principle.

The workforce’s new resolution builds on an extension of Einstein’s principle often known as Finsler gravity.

Developed over current years, the framework generalizes the geometry of spacetime itself, permitting for a extra detailed description of how matter — particularly gases — behaves below gravity.

Unlike basic relativity, which depends on a selected geometric construction, Finsler gravity permits a richer and extra versatile spacetime geometry.

Using this method, the examine authors recalculated the equations that govern the Universe’s growth.

When expressed throughout the Finsler framework, the modified Friedmann equations naturally predict an accelerated growth of the Universe — even in a vacuum, and with out introducing any further darkish power element.

In different phrases, the acceleration emerges from the geometry of spacetime itself.

“This is an exciting indication that we may be able to explain the accelerated expansion of the Universe, at least in parts, without dark energy, on the basis of a generalized spacetime geometry,” Dr. Pfeifer mentioned.

The thought doesn’t declare to get rid of darkish power totally, nor does it instantly overturn the Standard Model.

Instead, it means that at the very least a number of the results attributed to darkish power may come up from a deeper and extra nuanced description of gravity.

“This new geometric point of view on the dark energy problem opens up new possibilities for better understanding the laws of nature in the cosmos,” Dr. Pfeifer mentioned.

The workforce’s paper was printed within the Journal of Cosmology and Astroparticle Physics.

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Christian Pfeifer et al. 2025. From kinetic gases to an exponentially increasing Universe — the Finsler-Friedmann equation. JCAP 10: 050; doi: 10.1088/1475-7516/2025/10/050