NASA astrophysicists made an important scientific discovery - they experimentally confirmed the inflationary theory of the evolution of the Universe.
Scientists are convinced that they “touched” events approximately 14,000,000,000 years ago. After three years of continuous observations of the cosmic background in the microwave range, they were able to “catch” the light remaining (relict) from the first moments of the life of the Universe. These discoveries were made using the WMAP (Wilkinson Microwave Anisotropy Probe) apparatus.
Astrophysicists study the Universe at that moment in its existence, when its age was about one trillionth of a second, that is, almost immediately after the Big Bang. It was at this moment that the beginnings of future hundreds of millions of galaxies appeared in the tiny Universe, from which stars and planets subsequently formed over hundreds of millions of years.
The leading postulate of the inflationary theory is this: after the Big Bang, which gave rise to our Universe, in an incredibly short period of time - a trillionth of a second - it turned from a microscopic object into something colossal, many times larger than the entire observable part of space, that is, it underwent inflation.
“The results are in favor of inflation,” said Charles Bennett (Johns Hopkins University), who reported the discovery. "It's amazing that we can say anything at all about what happened in the first trillionth of a second of the universe's existence," he said.
Apparently, in the first trillionths of a second after the Explosion, the expansion rate of the Universe was higher than the speed of light, and the time that passed from the moment the Universe expanded from the size of several atoms to a stable spherical shape is measured in very small quantities. This hypothesis was first put forward in the 80s.
“How do we know what was in the Universe at the time of its creation? The cosmic microwave background is a real treasure trove of information about the past of our Universe. The light radiation that has reached us clearly indicates the facts of the development of the Universe,” says Dr. Gary Hinshaw, employee NASA Goddard Space Center.
The inflation theory itself exists in several versions, astronomer Nikolai Nikolaevich Chugai (Institute of Astronomy RAS) tells NewsInfo.
“There is no complete theory of this, but there are only some assumptions about how this happened. But there is one “prediction” that follows from the fact that quantum fluctuations (from the Latin fluctuatio - oscillation; random deviations of physical quantities from their average values on microscopic scales) predict a certain spectrum of disturbances, that is, the distribution of the amplitude of these disturbances depending on the length of the scale on which this disturbance develops. You can imagine in the figure a wavy line with different wavelengths, and if you have one amplitude for large-scale ones, then for small-scale ones it’s different - you say that the spectrum of these disturbances is not flat,” explains Nikolai Chugai.
Until about the 1970s of the 20th century, there was a standard picture of the Big Bang, according to which our Universe arose from a very dense, hot state. Thermonuclear fusion of helium has occurred - this is one of the confirmations of the model of a hot Universe. In 1964, relict (residual) radiation was discovered, for which the Nobel Prize was received. CMB radiation comes to us from very distant regions. During the expansion process, the radiation filling the larger Universe cools.
“This property is similar to when a balloon bursts and becomes cold,” explains Nikolai Chugai. “The same thing happens when the spray escapes from your balloon, and you can feel the balloon cooling.”
“The discovery of this radiation (it is now cold - only 3 degrees) was decisive evidence of the hot phase of the Universe. But this model is not complete,” says the astronomer. “It does not explain everything. And the main thing is that it does not explain the fact that the Universe is homogeneous on all scales. Wherever we look, we see almost identical galaxies with the same density of these galaxies in units of volume. Everywhere it is approximately the same. Since these distant points of the Universe do not interact, it turns out strange - from the point of view of physics - how they are. do not interact and know nothing about each other, relatively speaking? And, nevertheless, the Universe is structured in the same way at these distant points. And this should mean for a physicist that once these distant parts of the Universe were in contact. were part of a whole in which disturbances spread and these disturbances were smoothed out. That is, once the universe that we see now on large scales was physically unified - signals and disturbances from these distant points managed to pass through and smear the disturbances that arose there."
Today we observe precisely this homogeneity in distant points of the Universe in opposite regions of the sky as completely identical in density - relict radiation, which we observe with absolutely the same intensity and brightness. "No matter where you look," says Dr. Chugai.
“And this means that the Universe was absolutely homogeneous - isotropic. This initial inflationary stage allows us to “prepare” such a homogeneous universe. Another advantage of the inflationary phase is not only that it prepared a homogeneous universe, but also that so-called quantum fluctuations (perturbation of density on microscopic length scales) were associated with the quantum nature of our world (at the level of elementary particles),” concluded Nikolai Chugai.
Listen to the sounds of a simulated Big Bang.
Materials used in the article:
2.Ringside Seat to the Universe's First Split Second 3.Russian media
The Big Bang is confirmed by many facts:
From Einstein's general theory of relativity it follows that the universe cannot be static; it must either expand or contract.
The further away a galaxy is, the faster it moves away from us (Hubble's law). This indicates the expansion of the universe. The expansion of the universe means that in the distant past the universe was small and compact.
The Big Bang model predicts that the cosmic microwave background radiation should appear in all directions, having a black body spectrum and a temperature of about 3°K. We observe the exact spectrum of a black body with a temperature of 2.73°K.
CMB radiation is uniform up to 0.00001. A small unevenness must exist to explain the uneven distribution of matter in the universe today. Such unevenness is also observed in the predicted size.
The Big Bang theory predicts the observed amounts of primordial hydrogen, deuterium, helium, and lithium. No other models can do this.
The Big Bang theory predicts that the universe changes over time. Because the speed of light is finite, observing at long distances allows us to look into the past. Among other changes, we see that when the universe was younger, quasars were more common and stars were bluer.
There are at least 3 ways to determine the age of the Universe. I will describe below:
*Age of chemical elements.
*Age of the oldest globular clusters.
*Age of the oldest white dwarf stars.
*The age of the Universe can also be estimated from cosmological models based on the Hubble Constant, as well as matter and dark energy densities. This model-based age is currently 13.7 ± 0.2 billion years.
Experimental measurements are consistent with the age-based model, which strengthens our confidence in the Big Bang model.
To date, the COBE satellite has mapped the background radiation with its wave-like structures and amplitude fluctuations over several billion light-years from Earth. All these waves are greatly enlarged images of those tiny structures from which the Big Bang began. The size of these structures was even smaller than the size of subatomic particles.
The new MAP (Microwave Anisotropy Probe) satellite, which was sent into space last year, deals with the same problems. Its mission is to collect information about the microwave radiation left over from the Big Bang.
Light coming to Earth from distant stars and galaxies (regardless of their location relative to the Solar System) has a characteristic red shift (Barrow, 1994). This shift is due to the Doppler effect - an increase in the length of light waves as the light source quickly moves away from the observer. Interestingly, this effect is observed in all directions, which means that all distant objects are moving away from the solar system. However, this does not happen because the Earth is the center of the Universe. Rather, the situation can be described using a comparison with a balloon painted with polka dots. As the balloon inflates, the distance between the peas increases. The universe is expanding and has been doing so for a long time. Cosmologists believe that the Universe was formed within one minute 10-20 billion years ago. It “flew out in all directions” from one point where matter was in a state of unimaginable concentration. This event is called the Big Bang.
The decisive evidence in favor of the Big Bang theory was the existence of background cosmic radiation, the so-called cosmic microwave background radiation. This radiation is a residual sign of the energy released at the beginning of the explosion. The CMB was predicted in 1948 and experimentally detected in 1965. It is microwave radiation that can be detected anywhere in space, and creates a background for all other radio waves. The radiation has a temperature of 2.7 degrees Kelvin (Taubes, 1997). The omnipresence of this residual energy confirms not only the fact of the origin (and not the eternal existence) of the Universe, but also that its birth was explosive.
If we assume that the Big Bang occurred 13,500 million years ago (which is supported by several facts), then the first galaxies arose from giant gas accumulations about 12,500 million years ago (Calder, 1983). The stars of these galaxies were microscopic accumulations of highly compressed gas. The strong gravitational pressure in their cores initiated thermonuclear fusion reactions, converting hydrogen into helium with a by-product energy emission (Davies, 1994). As stars aged, the atomic mass of the elements within them increased. In fact, all elements heavier than hydrogen are products of stars. In the hot furnace of the stellar core, heavier and heavier elements were formed. It was in this way that iron and elements with lower atomic mass appeared. When the early stars used up their fuel, they could no longer resist the forces of gravity. The stars collapsed and then exploded as supernovae. During supernova explosions, elements with atomic masses greater than iron appeared. The heterogeneous intrastellar gas left behind by early stars became the building material from which new solar systems could form. The accumulations of this gas and dust formed partly as a result of the mutual attraction of particles. If the mass of the gas cloud reached a certain critical limit, gravitational pressure triggered the process of nuclear fusion and a new one was born from the remains of the old star.
Evidence for the Big Bang model comes from a variety of observed data that are consistent with the Big Bang model. None of this evidence for the Big Bang is conclusive as a scientific theory. Many of these facts are consistent with both the Big Bang and some other cosmological models, but taken together these observations show that the Big Bang model is the best model of the Universe today. These observations include:
The blackness of the night sky - Olber's Paradox.
Hubble's Law - The law of linear dependence of distance on redshift. This data is very accurate today.
Homogeneity is clear data showing that our location in the Universe is not unique.
Space isotropy is very clear data showing that the sky looks the same in all directions to within 1 part in 100,000.
Time dilation in supernova brightness curves.
The observations above are consistent with both the Big Bang and the Steady-State Model, but many observations support the Big Bang better than the Steady-State Model:
Dependence of the number of radio sources and quasars on brightness. It shows that the Universe has evolved.
The existence of black-body cosmic microwave background radiation. This shows that the Universe evolved from a dense, isothermal state.
Change Trelikt. with a change in redshift value. This is a direct observation of the evolution of the Universe.
Contents of Deuterium, 3He, 4He, and 7Li. The abundances of all these light isotopes correspond well to the predicted reactions occurring in the first three minutes.
Finally, the one part per million angular intensity anisotropy of the CMB is consistent with a dark matter-dominated Big Bang model that went through an inflationary stage.
Precise measurements carried out by the COBE satellite confirmed that the cosmic microwave background radiation fills the Universe and has a temperature of 2.7 degrees Kelvin. This radiation is recorded from all directions and is quite uniform. According to the theory, the Universe is expanding and, therefore, it should have been denser in the past. And therefore the radiation temperature at that time should be higher. Now this is an indisputable fact.
Chronology:
* Planck time: 10-43 seconds. Through this gap time, gravity can be considered as a classical background against which particles and fields develop, while obeying the laws of quantum mechanics. The area about 10-33 cm in diameter is homogeneous and isotropic, Temperature T=1032K.
* Inflation. In Linde's chaotic inflation model, inflation begins at Planck time, although it can begin when the temperature drops to the point where the Grand Unified Theory (GUT) symmetry suddenly breaks. This occurs at temperatures between 1027 and 1028K 10-35 seconds after the Big Bang.
* Inflation ends. The time is 10-33 seconds, the temperature is still 1027 - 1028K because the vacuum energy density, which accelerates inflation, is converted into heat. At the end of inflation, the rate of expansion is so great that the apparent age of the Universe is only 10-35 seconds. Thanks to inflation, the homogeneous region from the Planck moment in time has a diameter of at least 100 cm, i.e. has increased more than 1035 times since Planck time. However, quantum fluctuations during inflation create regions of inhomogeneity with low amplitude and random distribution, having the same energy in all ranges.
* Baryogenesis: The slight difference in reaction rates for matter and antimatter results in a mixture containing about 100,000,001 protons for every 100,000,000 antiprotons (and 100,000,000 photons).
* The Universe grows and cools until 0.0001 seconds after the Big Bang and a temperature of about T=1013 K. Antiprotons annihilate with protons, leaving only matter, but with a very large number of photons for each surviving proton and neutron.
* The Universe grows and cools until 1 second after the Big Bang, temperature T = 1010 K. Weak interactions are frozen out at a proton/neutron ratio of about 6. The homogeneous region reaches a size of 1019.5 cm by this moment.
* The universe grows and cools until 100 seconds after the Big Bang. Temperature 1 billion degrees, 109 K. Electrons and positrons annihilate, forming even more photons, while protons and neutrons combine to form deuterium (heavy hydrogen) nuclei. Most of the deuterium nuclei combine to form helium nuclei. Ultimately, the mass is about 3/4 hydrogen, 1/4 helium; the deuterium/proton ratio is 30 ppm. For every proton or neutron, there are about 2 billion photons.
* A month after the BW, the processes that transform the radiation field to the radiation spectrum of a completely black body weaken; now they lag behind the expansion of the Universe, so the spectrum of the cosmic microwave background radiation retains information relating to this time.
*Matter density compared to radiation density 56,000 years after WW. Temperature 9000 K. Inhomogeneities of dark matter may begin to shrink.
* Protons and electrons combine to form neutral hydrogen. The universe becomes transparent. Temperature T=3000 K, time 380,000 years after WW. Ordinary matter can now fall onto dark matter clouds. The CMB travels freely from this time until the present, so the anisotropy of the CMB gives a picture of the Universe at that time.
* 100-200 million years after the BV, the first stars are formed, and with their radiation they again ionize the Universe.
* The first supernovae explode, filling the Universe with carbon, nitrogen, oxygen, silicon, magnesium, iron, and so on, all the way to Uranus.
* As clouds of dark matter, stars and gas gather together, galaxies are formed.
* Clusters of galaxies are formed.
* 4.6 billion years ago the Sun and the Solar System were formed.
* Today: Time 13.7 billion years after the Big Bang, temperature T=2.725 K. The homogeneous area today is at least 1029 cm across, which is larger than the observable part of the Universe.
There was a Big Bang! Here is what, for example, academician Ya.B. wrote about this. Zeldovich in 1983: “The Big Bang theory at the moment does not have any noticeable shortcomings. One might even say that it is as firmly established and true as it is true that the Earth revolves around the Sun. Both theories occupied a central place in the picture of the universe of their time, and both had many opponents who argued that the new ideas contained in them were absurd and contrary to common sense. But such speeches are not able to hinder the success of new theories.”
Radio astronomy data indicate that in the past, distant extragalactic radio sources emitted more radiation than they do now. Consequently, these radio sources are evolving. When we now observe a powerful radio source, we must not forget that we are looking at its distant past (after all, radio telescopes today receive waves that were emitted billions of years ago). The fact that radio galaxies and quasars evolve, and the time of their evolution is commensurate with the time of existence of the Metagalaxy, is also generally considered in favor of the Big Bang theory.
An important confirmation of the “hot Universe” follows from a comparison of the observed abundance of chemical elements with the ratio between the amount of helium and hydrogen (about 1/4 helium and about 3/4 hydrogen) that arose during primordial thermonuclear fusion.
Abundance of light elements
The early Universe was very hot. Even if protons and neutrons combined during a collision and formed heavier nuclei, their lifetime was negligible, because the next time they collided with another heavy and fast particle, the nucleus again disintegrated into elementary components. It turns out that about three minutes had to pass from the moment of the Big Bang before the Universe cooled down enough for the energy of collisions to soften somewhat and elementary particles began to form stable nuclei. In the history of the early Universe, this marked the opening of a window of opportunity for the formation of nuclei of light elements. All nuclei formed in the first three minutes inevitably disintegrated; Subsequently, stable nuclei began to appear.
However, this initial formation of nuclei (the so-called nucleosynthesis) at the early stage of the expansion of the Universe did not last very long. Soon after the first three minutes, the particles flew so far apart that collisions between them became extremely rare, and this marked the closing of the nuclear fusion window. During this brief period of primary nucleosynthesis, the collisions of protons and neutrons produced deuterium (a heavy isotope of hydrogen with one proton and one neutron in the nucleus), helium-3 (two protons and a neutron), helium-4 (two protons and two neutrons) and, in small quantities, lithium-7 (three protons and four neutrons). All heavier elements are formed later - during the formation of stars (see Evolution of stars).
The Big Bang theory allows us to determine the temperature of the early Universe and the frequency of particle collisions in it. As a consequence, we can calculate the ratio of the number of different nuclei of light elements at the primary stage of the development of the Universe. By comparing these predictions with the actual observed ratios of light elements (adjusted for their production in stars), we find an impressive agreement between theory and observations. In my opinion, this is the best confirmation of the Big Bang hypothesis.
In addition to the two evidence given above (microwave background and the ratio of light elements), recent work (see Inflationary stage of expansion of the Universe) has shown that the fusion of Big Bang cosmology and modern theory of elementary particles resolves many cardinal questions of the structure of the Universe. Of course, problems remain: we cannot explain the very root cause of the universe; It is also not clear to us whether the current physical laws were in effect at the moment of its origin. But today there are more than enough convincing arguments in favor of the Big Bang theory.
- Translation
What happened before the Big Bang? The period of inflation (if there actually was one). What do we know about what happened before inflation?
Of course, there is a lot of scientific speculation about what happened before. But there are many of them, they contradict each other, and today we do not have data that could help us know which of these arguments are true. There is not even a leading theory, the probability of which most scientists would assess as greatest. It's just that nothing is known about it. It may even turn out that the inflation process continues to this day, and it continues in most of the Universe, sometimes stopping in small parts of it (large compared to the part of the Universe we observe, but small compared to the Universe as a whole).
And after inflation there was a hot Big Bang. In a previous article clarifying the confusion surrounding the Big Bang, it was explained that the Universe is not expanding “into something”—there is no such thing as “out there.” Now let's take a closer look at the Big Bang itself, which was not really an "explosion" but an expansion of space, despite what countless books, videos, articles and statements often describe. Let's look at the differences between exploding something in space and expanding space itself.
Rice. 1
In Fig. Figure 1 shows the situation before and after the explosion. Initially, in this example, there is a certain space with a seed in the middle, the role of which is played by a bomb, a grenade, a star, or another form of stored energy. Both space and seed exist in advance. Then something happens and the seed explodes. The contents of the seed undergo some transformation - for example, a chemical or nuclear reaction occurs - releasing energy. This creates enormous temperature and pressure inside the seed. Forces associated with compressed temperature and pressure cause the insides of the seed to expand outward in the form of a hot ball of matter. The energy rushes out of it at a high speed, with a temperature initially equal to that of the inside of the seed, and then the pressure and temperature gradually drops as the inside of the seed expands outward into the pre-existing space around it in which it was originally located.
Note that the explosion was caused by a reaction that created extremely high pressure and temperature within a tiny region. It is the imbalance between the enormous pressure and temperature inside the seed and the low pressure and temperature outside that causes the seed to explode outward. And everything that was inside is moving away from its original location at high speed. The speed at which they move away from the starting point cannot exceed the speed of light, so there are limits on how fast they can move away from each other.
In Fig. Figure 2 depicts the process (which, in principle, could have been going on even before the moment shown on the left) of space expansion. Between the image on the left and the image on the right, the space has doubled, as can be seen by the grid lines. Everything that is inside space and held together by powerful forces - chairs, tables, cats and people - does not expand. Only the space in which they all reside expands. In short, there is more space, so there is more room for the objects inside it.
In this case, the objects essentially do not move! They are not pushed away by pressure or temperature, no one kicks them. It's just that the space between them and around them grows, appears out of nowhere, and makes the distance between them greater than before. And this increase is uniform (for uniform expansion). In the right image, the distance between the cat and the table has doubled, as has the distance between the cat and the chair. This is what happens when the Universe doubles in size.
Rice. 2
Such a change in space is possible according to Einstein's theory of gravity, but not according to Newton's older theory. For Einstein, space is not just a place where everything happens; it is a thing in itself, capable of growing, shrinking, deforming, oscillating and changing shape. (More precisely, space and time do all this jointly). The ripples in spacetime are called gravitational waves.
Since space is expanding and objects are not moving, the theory of relativity does not impose restrictions on the rate at which the distance between objects grows, that is, on the rate at which new space appears between them. The distance between two objects can increase faster than the speed of light. There is no contradiction with the theory of relativity.
People often say, in imprecise and general phrases, things like “the theory of relativity states that nothing can travel faster than light.” But the words "nothing" and "move" have multiple meanings, and science tells us that using imprecise words can lead to problems. Einstein's words, if you read them, are also often ambiguous and easy to misunderstand, even though he tried to be precise. But Einstein's equations are not ambiguous. The exact statement of the theory of relativity is that if two objects pass by each other at the same place in space, and an observer moves along with one of them, then the speed of the other object from the point of view of that observer will not be greater than the speed of light. But this does not contradict what I claim: that the distance between two objects located in different places can increase faster. And this will happen in a uniformly expanding Universe if two objects are far enough from each other.
Also note that the expansion of the universe, unlike an explosion, is not caused by temperature or pressure. I specifically drew the normal objects, tables and chairs, so you can see that compared to an explosion that would damage or destroy normal objects, the expansion leaves them intact, they just move away from each other. Expansion can occur in a very hot universe - and it did in the early history of our universe, during the hot Big Bang. But expansion can also occur in a very cold universe. There is a suspicion that this also happened during the period of cosmic inflation. And, of course, our Universe today is quite cold, but it is not just expanding, but expanding at an accelerating rate.
The era of the hot Big Bang, in the final stages of which we are living, began at some point in time as a large region of space filled with a hot, dense soup of particles, which first expanded and cooled very quickly, and then did so more and more slowly, until moment that occurred several billion years ago. It didn't start out as a point object exploding in empty space. We will look at how a hot Big Bang could have started after inflation in future articles.
The Big Bang theory has become almost as widely accepted a cosmological model as the Earth's rotation around the Sun. According to the theory, about 14 billion years ago, spontaneous vibrations in absolute emptiness led to the emergence of the Universe. Something comparable in size to a subatomic particle expanded to unimaginable sizes in a fraction of a second. But there are many problems in this theory that physicists are struggling with, putting forward more and more new hypotheses.
What's wrong with the Big Bang Theory
From the theory it follows that all planets and stars were formed from dust scattered throughout space as a result of an explosion. But what preceded it is unclear: here our mathematical model of space-time stops working. The Universe arose from an initial singular state, to which modern physics cannot be applied. The theory also does not consider the causes of the singularity or the matter and energy for its occurrence. It is believed that the answer to the question of the existence and origin of the initial singularity will be provided by the theory of quantum gravity.
Most cosmological models predict that the complete Universe is much larger than the observable part - a spherical region with a diameter of approximately 90 billion light years. We see only that part of the Universe, the light from which managed to reach the Earth in 13.8 billion years. But telescopes are getting better, we are discovering more and more distant objects, and there is no reason to believe that this process will stop.
Since the Big Bang, the Universe has been expanding at an accelerating rate. The most difficult mystery of modern physics is the question of what causes acceleration. According to the working hypothesis, the Universe contains an invisible component called “dark energy.” The Big Bang theory does not explain whether the Universe will expand indefinitely, and if so, what will this lead to - its disappearance or something else.
Although Newtonian mechanics was supplanted by relativistic physics, it cannot be called erroneous. However, the perception of the world and the models for describing the Universe have completely changed. The Big Bang theory predicted a number of things that were not known before. Thus, if another theory comes to replace it, it should be similar and expand the understanding of the world.
We will focus on the most interesting theories describing alternative models of the Big Bang.
The Universe is like a mirage of a black hole
The Universe arose due to the collapse of a star in a four-dimensional Universe, according to scientists from the Perimeter Institute of Theoretical Physics. The results of their study were published by Scientific American. Niayesh Afshordi, Robert Mann and Razi Pourhasan say that our three-dimensional Universe became a kind of “holographic mirage” when a four-dimensional star collapsed. Unlike the Big Bang theory, which posits that the universe arose from an extremely hot and dense space-time where the standard laws of physics do not apply, the new hypothesis of a four-dimensional universe explains both the origins and its rapid expansion.
According to the scenario formulated by Afshordi and his colleagues, our three-dimensional Universe is a kind of membrane that floats through an even larger universe that already exists in four dimensions. If this four-dimensional space had its own four-dimensional stars, they would also explode, just like the three-dimensional ones in our Universe. The inner layer would become a black hole, and the outer one would be thrown into space.
In our Universe, black holes are surrounded by a sphere called the event horizon. And if in three-dimensional space this boundary is two-dimensional (like a membrane), then in a four-dimensional universe the event horizon will be limited to a sphere that exists in three dimensions. Computer simulations of the collapse of a four-dimensional star have shown that its three-dimensional event horizon will gradually expand. This is exactly what we observe, calling the growth of the 3D membrane the expansion of the Universe, astrophysicists believe.
Big Freeze
An alternative to the Big Bang is the Big Freeze. A team of physicists from the University of Melbourne, led by James Kvatch, presented a model of the birth of the Universe, which is more reminiscent of the gradual process of freezing amorphous energy than its release and expansion in three directions of space.
Formless energy, according to scientists, like water, cooled to crystallization, creating the usual three spatial and one temporal dimensions.
The Big Freeze theory challenges Albert Einstein's currently accepted assertion of the continuity and fluidity of space and time. It is possible that space has components - indivisible building blocks like tiny atoms or pixels in computer graphics. These blocks are so small that they cannot be observed, however, following the new theory, it is possible to detect defects that should refract the flow of other particles. Scientists have calculated such effects using mathematics, and now they will try to detect them experimentally.
Universe without beginning and end
Ahmed Farag Ali from Benha University in Egypt and Saurya Das from the University of Lethbridge in Canada have proposed a new solution to the singularity problem by abandoning the Big Bang. They introduced the ideas of the famous physicist David Bohm into the Friedmann equation describing the expansion of the Universe and the Big Bang. “It's amazing that small adjustments can potentially solve so many issues,” says Das.
The resulting model combined general relativity and quantum theory. It not only denies the singularity that preceded the Big Bang, but also does not admit that the Universe will eventually contract back to its original state. According to the data obtained, the Universe has a finite size and an infinite lifetime. In physical terms, the model describes a Universe filled with a hypothetical quantum fluid, which consists of gravitons - particles that provide gravitational interaction.
The scientists also claim that their findings are consistent with recent measurements of the density of the Universe.
Endless chaotic inflation
The term “inflation” refers to the rapid expansion of the Universe, which occurred exponentially in the first moments after the Big Bang. The inflation theory itself does not disprove the Big Bang theory, but only interprets it differently. This theory solves several fundamental problems in physics.
According to the inflationary model, shortly after its birth, the Universe expanded exponentially for a very short time: its size doubled many times over. Scientists believe that in 10 to -36 seconds, the Universe increased in size by at least 10 to 30 to 50 times, and possibly more. At the end of the inflationary phase, the Universe was filled with superhot plasma of free quarks, gluons, leptons and high-energy quanta.
The concept implies what exists in the world many universes isolated from each other with different device
Physicists have come to the conclusion that the logic of the inflationary model does not contradict the idea of the constant multiple birth of new universes. Quantum fluctuations - the same as those that created our world - can arise in any quantity if the conditions are right for them. It is quite possible that our universe has emerged from the fluctuation zone that formed in the predecessor world. It can also be assumed that someday and somewhere in our Universe a fluctuation will form that will “blow out” a young Universe of a completely different kind. According to this model, daughter universes can bud off continuously. Moreover, it is not at all necessary that the same physical laws are established in new worlds. The concept implies that in the world there are many universes isolated from each other with different structures.
Cyclic theory
Paul Steinhardt, one of the physicists who laid the foundations of inflationary cosmology, decided to develop this theory further. The scientist, who heads the Center for Theoretical Physics at Princeton, together with Neil Turok from the Perimeter Institute for Theoretical Physics, outlined an alternative theory in the book Endless Universe: Beyond the Big Bang ("The Infinite Universe: Beyond the Big Bang"). Their model is based on a generalization of quantum superstring theory known as M-theory. According to it, the physical world has 11 dimensions - ten spatial and one temporal. Spaces of lower dimensions, the so-called branes, “float” in it. (short for "membrane"). Our Universe is simply one of these branes.
The Steinhardt and Turok model states that the Big Bang occurred as a result of the collision of our brane with another brane - an unknown universe. In this scenario, collisions occur endlessly. According to the hypothesis of Steinhardt and Turok, another three-dimensional brane “floats” next to our brane, separated by a tiny distance. It is also expanding, flattening and emptying, but after a trillion years the branes will begin to move closer together and eventually collide. This will release a huge amount of energy, particles and radiation. This cataclysm will trigger another cycle of expansion and cooling of the Universe. From the model of Steinhardt and Turok it follows that these cycles have existed in the past and will certainly repeat in the future. The theory is silent about how these cycles began.
Universe
like a computer
Another hypothesis about the structure of the universe says that our entire world is nothing more than a matrix or a computer program. The idea that the Universe is a digital computer was first put forward by German engineer and computer pioneer Konrad Zuse in his book Calculating Space (“Computational space”). Among those who also considered the Universe as a giant computer are physicists Stephen Wolfram and Gerard 't Hooft.
Digital physics theorists propose that the universe is essentially information, and therefore computable. From these assumptions it follows that the Universe can be considered as the result of a computer program or a digital computing device. This computer could be, for example, a giant cellular automaton or a universal Turing machine.
Indirect evidence virtual nature of the universe called the uncertainty principle in quantum mechanics
According to the theory, every object and event in the physical world comes from asking questions and recording “yes” or “no” answers. That is, behind everything that surrounds us, there is a certain code, similar to the binary code of a computer program. And we are a kind of interface through which access to the data of the “universal Internet” appears. An indirect proof of the virtual nature of the Universe is called the uncertainty principle in quantum mechanics: particles of matter can exist in an unstable form, and are “fixed” in a specific state only when they are observed.
Digital physicist John Archibald Wheeler wrote: “It would not be unreasonable to imagine that information resides in the core of physics as in the core of a computer. Everything is from the bit. In other words, everything that exists - every particle, every force field, even the space-time continuum itself - receives its function, its meaning and, ultimately, its very existence."
Even modern scientists cannot say with certainty what was in the Universe before the Big Bang. There are several hypotheses that lift the veil of secrecy over one of the most complex issues of the universe.
Origin of the material world
Until the 20th century, there were only two supporters of the religious point of view, who believed that the world was created by God. Scientists, on the contrary, refused to acknowledge the man-made nature of the Universe. Physicists and astronomers were supporters of the idea that space has always existed, the world was static and everything will remain the same as billions of years ago.
However, accelerated scientific progress at the turn of the century led to the fact that researchers had opportunities to study extraterrestrial spaces. Some of them were the first to try to answer the question of what was in the Universe before the Big Bang.
Hubble Research
The 20th century destroyed many theories of past eras. In the vacated space, new hypotheses appeared that explained hitherto incomprehensible mysteries. It all started with the fact that scientists established the fact of the expansion of the Universe. This was done by Edwin Hubble. He discovered that distant galaxies differed in their light from those cosmic clusters that were closer to Earth. The discovery of this pattern formed the basis of Edwin Hubble's law of expansion.
The Big Bang and the origin of the Universe were studied when it became clear that all galaxies “escape” from the observer, no matter where he was. How could this be explained? Since galaxies move, it means that they are pushed forward by some kind of energy. In addition, physicists have calculated that all worlds were once located at one point. Due to some push, they began to move in all directions with unimaginable speed.
This phenomenon was called the “Big Bang”. And the origin of the Universe was explained precisely with the help of the theory of this ancient event. When did it happen? Physicists determined the speed of movement of galaxies and derived a formula that they used to calculate when the initial “push” occurred. No one can give exact numbers, but approximately this phenomenon took place about 15 billion years ago.
The emergence of the Big Bang theory
The fact that all galaxies are sources of light means that the Big Bang released a huge amount of energy. It was she who gave birth to the very brightness that the worlds lose as they move away from the epicenter of what happened. The Big Bang theory was first proven by American astronomers Robert Wilson and Arno Penzias. They discovered electromagnetic cosmic microwave background radiation, the temperature of which was three degrees on the Kelvin scale (that is, -270 Celsius). This find supported the idea that the Universe was initially extremely hot.
The Big Bang theory answered many questions formulated in the 19th century. However, now new ones have appeared. For example, what was in the Universe before the Big Bang? Why is it so homogeneous, while with such a huge release of energy the substance should scatter unevenly in all directions? The discoveries of Wilson and Arno cast doubt on classical Euclidean geometry, as it was proven that space has zero curvature.
Inflationary theory
New questions posed showed that the modern theory of the origin of the world is fragmentary and incomplete. However, for a long time it seemed that it would be impossible to advance beyond what was discovered in the 60s. And only very recent research by scientists has made it possible to formulate a new important principle for theoretical physics. This was the phenomenon of ultra-fast inflationary expansion of the Universe. It was studied and described using quantum field theory and Einstein's general theory of relativity.
So what was in the Universe before the Big Bang? Modern science calls this period “inflation.” In the beginning there was only a field that filled all imaginary space. It can be compared to a snowball thrown down the slope of a snowy mountain. The lump will roll down and increase in size. In the same way, the field, due to random fluctuations, changed its structure over an unimaginable time.
When a homogeneous configuration was formed, a reaction occurred. It contains the biggest mysteries of the Universe. What happened before the Big Bang? An inflationary field that was not at all like current matter. After the reaction, the growth of the Universe began. If we continue the analogy with a snowball, then after the first one, other snowballs rolled down, also increasing in size. The moment of the Big Bang in this system can be compared to the second when a huge block fell into the abyss and finally collided with the ground. At that moment, a colossal amount of energy was released. It still can't run out. It is due to the continuation of the reaction from the explosion that our Universe is growing today.
Matter and field
The Universe now consists of an unimaginable number of stars and other cosmic bodies. This aggregate of matter exudes enormous energy, which contradicts the physical law of conservation of energy. What does it say? The essence of this principle comes down to the fact that over an infinite period of time the amount of energy in the system remains unchanged. But how can this fit in with our Universe, which continues to expand?
Inflationary theory was able to answer this question. It is extremely rare that such mysteries of the Universe are solved. What happened before the Big Bang? Inflationary field. After the emergence of the world, matter familiar to us took its place. However, in addition to it, there is also something in the Universe that has negative energy. The properties of these two entities are opposite. This compensates for the energy coming from particles, stars, planets and other matter. This relationship also explains why the Universe has not yet turned into a black hole.
When the Big Bang first happened, the world was too small for anything to collapse. Now, when the Universe has expanded, local black holes have appeared in certain parts of it. Their gravitational field absorbs everything around them. Not even light can get out of it. This is actually why such holes become black.
Expansion of the Universe
Even despite the theoretical justification of the inflationary theory, it is still unclear what the Universe looked like before the Big Bang. The human imagination cannot imagine this picture. The fact is that the inflation field is intangible. It cannot be explained by the usual laws of physics.
When the Big Bang occurred, the inflation field began to expand at a rate that exceeded the speed of light. According to physical indicators, there is nothing material in the Universe that could move faster than this indicator. Light spreads across the existing world with incredible numbers. The inflationary field spread with even greater speed, precisely due to its intangible nature.
Current State of the Universe
The current period in the evolution of the Universe is ideally suited for the existence of life. Scientists find it difficult to determine how long this time period will last. But if anyone undertook such calculations, the resulting figures were no less than hundreds of billions of years. For one human life, such a segment is so large that even in mathematical calculus it has to be written down using powers. The present has been studied much better than the prehistory of the Universe. What happened before the Big Bang will, in any case, remain only the subject of theoretical research and bold calculations.
In the material world, even time remains a relative value. For example, quasars (a type of astronomical object), existing at a distance of 14 billion light years from Earth, are 14 billion light years behind our usual “now”. This time gap is enormous. It is difficult to define even mathematically, not to mention the fact that it is simply impossible to clearly imagine such a thing with the help of human imagination (even the most ardent).
Modern science can theoretically explain to itself the entire life of our material world, starting from the first fractions of seconds of its existence, when the Big Bang just occurred. The complete history of the Universe is still being updated. Astronomers are discovering amazing new facts with the help of modernized and improved research equipment (telescopes, laboratories, etc.).
However, there are also phenomena that are still not understood. Such a white spot, for example, is its dark energy. The essence of this hidden mass continues to excite the consciousness of the most educated and advanced physicists of our time. In addition, no single point of view has emerged about the reasons why there are still more particles in the Universe than antiparticles. Several fundamental theories have been formulated on this matter. Some of these models are the most popular, but none of them has yet been accepted by the international scientific community as
On the scale of universal knowledge and colossal discoveries of the 20th century, these gaps seem quite insignificant. But the history of science shows with enviable regularity that the explanation of such “small” facts and phenomena becomes the basis for humanity’s entire understanding of the discipline as a whole (in this case we are talking about astronomy). Therefore, future generations of scientists will certainly have something to do and something to discover in the field of knowledge of the nature of the Universe.