Physicists predict reverse Big Bang date

If recent discoveries that dark energy is evolving are shown to be true, according to new calculations, the Universe will collapse under its own gravity within a finite time frame.

Based on several recent discoveries about , a new model concludes that the Universe has a total lifespan of just 33.3 billion years. That is, given that we are now 13.8 billion years after the Big Bang, this suggests that the Universe has just under 20 billion years left.

The new research, the results of which were presented in a study recently in Journal of Cosmology and Astroparticle Physicshe also added that, for another 11 billion years, the Universe will continue to expand, before stop and reverse direction, collapsing to the hypothetical Big Crunch.

O Big Crunch it is the opposite of the Big Bang, in which all the matter in the Universe compresses itself again into an infinitely dense singularity.

“Over the last 20 years, it was believed that the cosmological constant was positive and that the Universe will expand forever. However, new data seems to indicate that the cosmological constant is negative and that the Universe will end in a Big Crunch”, he told , Henry Tyefrom Cornell University (USA), who was part of the study.

As the same magazine explains, the cosmological constant that Tye refers to is λ, introduced by Albert Einstein in his theory of general relativity to describe the expansion of the Universe.

If the value of λ is positive, then it acts as a force that constantly pushes outward, contributing to the expansion of the Universe. If λ is negative, it behaves like a constant attraction that never disappears and that can eventually stop and reverse the expansion.

Recent observations suggest that dark energy may be changing over time. In the new model, the authors’ best adjustment corresponds to a small negative λalthough current data do not exclude that λ is equal to 0.

As a negative λ pulls inward, this would hinder, rather than favor, the expansion of the Universe.

Despite this, according to an overwhelming majority of evidence, the Universe is in fact expanding.

However, we can arrive at the observed behavior of the Universe if we combine a small negative λ with a field of ultralight axion which today behaves like dark energy.

As Science Alert describes, axions are ultralight particles that can also be understood as a soft, ethereal field throughout space, proposed for decades as a potential solution to other problems in particle physics.

The new analysis describes the axion as a force that gives the Universe a gentle outward push at first, but which slowly decreases over time.

Right now, the axion’s influence still predominates, pushing the Universe outward at an accelerating rate as gravity weakens between bodies moving further apart — so the Universe is still accelerating today in this scenario.

However, within about 11 billion yearsthe axion’s momentum will weaken enough for the negative λ pull to take over, causing the expansion of the Universe stopsreaching a maximum size of about 1.7 times its current size.

Afterwards, the Universe will begin to contract again — rushing into a Big Crunch in just 8 billion years.