The parallel worlds hypothesis is very popular among science fiction writers. Thanks to their texts, society has developed an idea of the universe as a set of all kinds of options for our own world. However, physicists believe that the real state of affairs is different from the imagined. And it seems that they have evidence of their own rightness.
OTHER MEASUREMENTS
The idea of the existence of parallel worlds became especially popular after astrophysicists proved that our Universe has a limited size (about 46 billion light years) and a certain age (13.8 billion years). Several questions arise at once. What is beyond the boundaries of the universe? What was before it emerged from the cosmological singularity? How did the cosmological singularity come about? What does the future hold for the universe? The hypothesis of parallel worlds gives a rational answer: in fact, there are many universes, they exist next to ours, are born and die, but we do not observe them, because we are not able to go beyond our three-dimensional space, just like a beetle crawling on one side of a paper leaf, see the beetle next to it, but on the other side of the leaf.
However, it is not enough for scientists to accept a beautiful hypothesis that will streamline our worldview, reducing it to everyday ideas - the presence of parallel worlds should manifest itself in various physical effects. And here a snag arose.
INFLATION THEORY
When the fact of the expansion of the Universe was comprehensively proved, and cosmologists began to build a model of its evolution from the Big Bang to the present, they faced a number of problems.
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The first problem is related to the average density of matter, which determines the curvature of space and, in fact, the future of the world we know. If the density of matter is below critical, then its gravitational effect will be insufficient to reverse the initial expansion caused by the Big Bang, so the universe will expand forever, gradually cooling to absolute zero. If the density is higher than the critical one, then, on the contrary, over time the expansion will turn into compression, the temperature will begin to increase until a fiery superdense object is formed. If the density is equal to the critical one, then the Universe will balance between the two named extreme states. Physicists have calculated the critical density: five hydrogen atoms per cubic meter. This is close to critical, although theoretically it should be much less. The second problem is the observed homogeneity of the universe. The microwave background radiation in areas of space separated by tens of billions of light years looks the same. If space expanded from some super-hot point-singularity, as the Big Bang theory claims, it would be “lumpy,” that is, different intensities of microwave radiation would be observed in different zones.
The third problem is the absence of monopoles, that is, hypothetical elementary particles with a nonzero magnetic charge, the existence of which was predicted by theory.
Trying to explain the discrepancies between the Big Bang theory and real observations, the young American physicist Alan Guth proposed in 1980 an inflationary model of the Universe (from inflatio - "swelling"), according to which at the initial moment of its birth, in the period from 10 ^ -42 seconds to 10 ^ -36 seconds The universe expanded 10 ^ 50 times.
Since the model of instant "bloat" removed the problems of the theory, it was enthusiastically accepted by most cosmologists. Among them was the Soviet scientist Andrei Dmitrievich Linde, who undertook to explain how such a fantastic "swelling" happened. In 1983 he proposed his own version of a model called the "chaotic" theory of inflation. Linde described a kind of infinite proto-universe, the physical conditions in which, unfortunately, we do not know. However, it is filled with a "scalar field", in which "discharges" occur from time to time, as a result of which "bubbles" of universes are formed. "Bubbles" quickly swell, which leads to a sudden increase in potential energy and the emergence of elementary particles, from which matter is then added.
Thus, the inflationary theory provides substantiation for the hypothesis of the existence of parallel worlds - as an infinite set of "bubbles" inflating in an infinite "scalar field".
VARIETY OF WORLDS
If we accept the inflationary theory as a description of the real world order, then new questions arise. Do the parallel worlds described by her differ from ours or are they identical in everything? Is it possible to get from one world to another? What is the evolution of these worlds?
Physicists say there can be an incredible variety of options. If in any of the newborn universes the density of matter is too high, it will collapse very quickly; if, on the contrary, it is too small, then they will expand forever. The opinion is expressed that the notorious "scalar field" is also present inside our Universe in the form of the so-called "dark energy", which continues to push galaxies apart. Therefore, it is possible that a spontaneous "discharge" may occur in our country, after which the Universe will "blossom into a bud", giving rise to new worlds.
The Swedish cosmologist Max Tegmark even put forward the hypothesis of the mathematical universe (also known as the Finite Ensemble), which claims that any mathematically consistent set of physical laws has its own independent, but quite real universe. Although it is unlikely that Tegmark's hypothesis will ever be tested with the help of an experiment, it answers the philosophical question: why are the observed physical laws and the values of fundamental constants exactly what they are? The answer is simple: because they are like that in this universe, and in some neighboring one they are different.
If the physical laws in neighboring universes are different from ours, then the conditions for evolution in them can be very unusual. Let's say there are more stable particles in some universe, such as protons. Then there must be more chemical elements, and life forms are much more complex than here, since compounds like DNA are created from more elements.
Is it possible to get to neighboring universes? Unfortunately no. For this, as physicists say, you need to learn to fly faster than the speed of light, which looks problematic.
NEW EVIDENCE
Although the Guta-Linde inflationary theory is generally accepted today, some scientists continue to criticize it, proposing their own Big Bang models. In addition, the effects predicted by theory have not yet been discovered.
At the same time, the very concept of the existence of parallel worlds, on the contrary, finds more and more supporters. A careful study of the microwave radiation map revealed an anomaly - a "relict cold spot" in the constellation Eridanus with unusually low radiation levels. Professor Laura Mersini-Houghton of the University of North Carolina believes that this is the "imprint" of the neighboring universe, from which ours may have been "inflated" - a kind of cosmological "navel". Another anomaly, dubbed "dark stream", is associated with the motion of galaxies: in 2008, a group of astrophysicists discovered that at least 1,400 galaxy clusters are flying through space in a specific direction under the influence of mass outside the visible part of the universe. One of the explanations proposed by the same Laura Mersini-Houghton,- they are attracted by the neighboring "mother" universe.
So far, such assumptions are considered speculation. But, I think, the day is not far off when physicists will dot all the i's. Or they will offer a beautiful new hypothesis.
Anton Pervushin