Is the universe a bubble? – Scientists have proposed a way to test this

A team led by researchers from Premier University in Canada conducted a computer simulation of the entire universe and actually two universes that collided on a computer, and then calculated what an observer on a planet within these universes would have seen

Scientists are looking for a way to test the Multiverse hypothesis (on Wikipedia “Parallel universe"). It sounds like a fictional story, and beyond the scope of science's investigation. Not to mention the fact that in the big bang everything started from nothing. The void floated with energies (various types of dark energy, void energy, the swelling field or the Higgs field). Like water in a kettle. This high energy began to evaporate and bubbles formed.

Each bubble contained another void inside, whose energy was lower, but still not zero. This energy caused the bubble to expand. Inevitably some of the bubbles collided with each other. Some of them may have formed secondary bubbles. These bubbles may have been few and far between, they may have been dense as foam. But here comes the interesting thing: each of these bubbles was for the universe. In the picture, our universe is one bubble in a teeming sea of ​​bubble universes. This is the multiverse theory at its peak.

This story is not made up, it emerges from our knowledge of cosmic inflation. However, this theory of the inflationary universe is not accepted by all researchers. Most cyclical models of the universe reject the idea. Despite this, inflation is the leading theory of the development of the universe at its very beginning and there is evidence to prove this, although The apparent proof of inflation However, in June 2014, the scientists in the BICEP2 team admitted that it is likely whose results stemmed from a struggle in the Milky Way galaxy.
See here (and thanks to the editors of Scientific American Israel for the link)

According to the theory, in the fraction of a second after the Big Bang, the universe expanded rapidly. So fast that an area that was one nanometer in diameter spread to a size of over a quarter of a billion light years within a trillionth of a trillionth of a trillionth of a second. It's an amazing idea, but it can explain otherwise puzzling astrophysical observations.

Inflation is driven by the inflation field - or the empty field (vacuum) by its other name. Once you start from the assumption that the inflation field exists, it is hard to ignore that it was initially empty. This is where the inflationary universe theory is controversial - when it raises the claim of multiple universes.

Supporters of the multiverse theory claim that it is the next logical step in the story of the inflationary universe. The opponents claim that this is not physics but metaphysics - that is, it is not science because it cannot be tested. After all, physics lives or dies on data that can be collected and predictions that can be tested.
Therefore, a team led by Matthew Johnson from the Premier Institute, together with his friends, including Lois Lehner, also from the Premier Institute, are working to bring the multiverse theory into the realm of testable science.
"We try to find out what the experimental predictions of the theory are, and then go and look for them," Johnson said. In particular he seeks to locate the rare cases where a bubble universe has collided with another bubble universe. "We conducted a computer simulation of the entire universe. We started with a multiverse containing two bubbles, and we caused the bubbles to collide on the computer to see what happened, and then we placed a simulated viewer in several places and asked what the viewer might see from there?"

To simulate the entire universe and more of more than one location seems like a difficult task, but it turns out not to be. "Simulating the universe is an easy thing" says Johnson and explains that computer simulation does not share all the atoms, stars and galaxies. "We only simulate the large scale of the universe" he said. "All I need is gravity and the things that make the bubble inflate. We're now at the point where we have a preferred model of the universe, and I can stick to a computer and tell you what you could see."

That's a small step for computer simulation software, but a giant leap for multiverse cosmology. By developing testable predictions, the multiverse model will straddle the line between a pretty story and real science.

In fact, Johnson says, the software has reached a point where some models of the multiverse can be excluded from it. "We can now say that some models are predicting something that we should have seen, and since we don't see it, we can remove them from the model." For example, a collision between one bubble universe and another may leave what Johnson calls a "disc in the sky" - a kind of wound in the cosmic background radiation. The search for such a disk has so far been unsuccessful and this means that certain collision models are unlikely.

Meanwhile, the team is working to find out what different kinds of evidence the bubble collisions might leave behind. This is the first time, the researchers write in their paper, that anyone has made a series of quantitative predictions for the observed signatures of bubble collisions. Although not a single such signature has been discovered, it is still possible to look for some of them.

The true meaning of the work is proof of capability: it shows that multiverses can be subjected to scientific scrutiny. In other words, if we live in a bubble universe, we may eventually find out.
Video: https://www.youtube.com/watch?v=w0uyR6JPkz4

to the notice of the researchers

In the same topic on the science website:

• Nir Lahav, Genesis was empty - part XNUMX - multiverse
• An Israeli researcher was involved in the development of a simulation of the universe
• The possibilities of life in a multiverse
• An Israeli researcher is looking at CERN for clues to new physics