Apocalypse: Universe could start shrinking 'significantly soon'

For more than 13 billion years, the universe has been constantly expanding, but that's about to change. According to a new research paper published in the Proceedings of the National Academy of Sciences, after nearly 13.8 billion years of continuous expansion, the universe could reach a path of progression. clogged, then begins to slowly shrink.

Since the 1990s, scientists have realised that the expansion of the universe is accelerating; The distance between galaxies is expanding faster now than it was billions of years ago.

Scientists have dubbed the mysterious source of this acceleration dark energy - an invisible entity that appears to work against gravity, pushing the massive objects in the universe apart rather than bunched together.

Although dark energy makes up nearly 70% of the universe's total energy, its properties remain a total mystery.

In the new paper, three scientists attempt to model the nature of dark energy - a mysterious force that appears to be causing the universe to expand faster - based on previous observations of cosmic expansion.

In the team's model, dark energy is not a constant force of nature. The researchers found that although the expansion of the universe has accelerated for billions of years, the repulsive force of dark energy may be weakening.

According to their model, the acceleration of the universe could end rapidly within the next 65 million years — then, in 100 million years, the universe could stop completely, and instead could enter an era of slow contraction that ends billions of years from now with death or perhaps re-establishment. The birth of time and place.

"The question we ask in this paper is, should this acceleration continue forever?" said study co-author Paul Steinhardt, director of the Princeton Centre for Theoretical Science at Princeton University in New Jersey. “And if not, what are the alternatives, and when might things change soon?”, “All of this can happen remarkably quickly.”

However, because the model relies on previous observations of expansion alone - and because the current nature of dark energy in the universe is a mystery - it is currently impossible to test the predictions in this study. For now, they can remain just theories.

Astrophysicist Dr. Jonathan Jiang, who works at NASA's Jet Propulsion Laboratory in California, revealed that he and his fellow scientists are considering sending images in the form of binary codes and codes that aliens can interpret, so that the symbols show the form of a completely naked man and woman, showing the details of their bodies, and they decided to attach the pictures With a message that explains to the aliens the mathematical sequences, in order to show them more pictures, in addition to more information about planet Earth, a representation of our solar system, and other images of the structure of human DNA.

An updated, binary-coded message has been developed for transmission to extraterrestrial intelligence in the Milky Way.

The proposed thesis includes basic mathematical and physical concepts, with the aim of creating a global means of communication between humans and aliens, as well as information on the biochemical composition of life on Earth, the chronological position of the Solar System in the Milky Way relative to globular star clusters, as well as digital imaging of the Solar System. and the earth's surface. The scientists decided to conclude the message with a digital anthropomorphic human figure, and to invite any of the aliens to respond to this message.

Regarding the means of delivering the message, Jiang and his companions suggested transmitting the message through the Chinese FAST telescope; a 500-meter telescope that China will use for space exploration, or perhaps via the SETI Allen Telescope Array in Northern California; It is an array of radio telescopes dedicated to astronomical observations and the search for extraterrestrial intelligence.

NASA justified this message that it needed compelling content to interest the recipient (the aliens), in addition to the need for a scientific basis to understand the message. It is worth noting that this message is an update of the so-called "Arecibo message" dating back to 1974, the Arecibo was sent into space as evidence of the technological achievements of man on Earth, and was not an attempt to enter into correspondence with an alien civilisation, as the new message is now.