Theoretical problems Wikipedia entry. Psychedelic - August 2013 Below is a list of unsolved problems in modern physics. Some of these problems are theoretical, which means that existing theories fail to explain certain

CHAPTER 14 SOLUTION FINDING A PROBLEM OR MANY PROBLEMS WITH THE SAME SOLUTION? LASER APPLICATIONS In 1898, Wells imagined in his book The War of the Worlds that the Martians would take over the Earth, using death rays that could easily pass through bricks, burn forests, and

II. social side Problems This side of the problem is, without a doubt, the most important and most interesting. In view of her great complexity we confine ourselves here to only the most general considerations.1. Changes in world economic geography. As we saw above, the cost

1.2. Astronomical Aspect of the ACH Problem The issue of assessing the significance of the asteroid-comet hazard is connected, first of all, with our knowledge of the population of the Solar System by small bodies, especially those that can collide with the Earth. Such knowledge is provided by astronomy.

New Problems of Cosmology Let us return to the paradoxes of nonrelativistic cosmology. Recall that the reason for the gravitational paradox is that either there are not enough equations to uniquely determine the gravitational effect, or there is no way to correctly set

CHAPTER 9 The Problems of Unification In 1947, fresh graduate student Bryce DeWitt met Wolfgang Pauli and told him that he was working on quantization. gravitational field. Devitt did not understand why the two great concepts of the 20th century - quantum physics and general theory

Can gravitational waves be detected?

Some observatories are busy looking for evidence of gravitational waves. If such waves can be found, these fluctuations in the space-time structure itself will indicate cataclysms occurring in the Universe such as supernova explosions, black hole collisions, and possibly still unknown events. For details, see W. Waite Gibbs' article "Space-Time Ripples".

What is the lifetime of a proton?

Some theories outside the Standard Model (see Chapter 2) predict the decay of the proton, and several detectors have been built to detect such decay. Although the decay itself has not yet been observed, the lower limit of the half-life of the proton is estimated at 10 32 years (significantly exceeding the age of the Universe). With the advent of more sensitive sensors, it may be possible to detect the decay of the proton, or it may be necessary to move the lower limit of its half-life.

Are superconductors possible at high temperatures?

Superconductivity occurs when the electrical resistance of a metal drops to zero. Under such conditions, the electric current established in the conductor flows without losses, which are characteristic of ordinary current when passing through conductors such as copper wire. The phenomenon of superconductivity was first observed at extremely low temperatures (just above absolute zero, -273 °C). In 1986, scientists succeeded in making materials superconducting at the boiling point of liquid nitrogen (-196 °C), which already allowed the creation of industrial products. The mechanism of this phenomenon is not yet fully understood, but researchers are trying to achieve superconductivity at room temperature, which will reduce energy losses.

How does the composition of a molecule determine its appearance?

Knowing the orbital structure of atoms in simple molecules makes it fairly easy to determine the appearance of a molecule. However, theoretical studies of the appearance of complex molecules, especially biologically important ones, have not yet been carried out. One aspect of this problem is protein folding, which is discussed in Idea List 8.

What are the chemical processes in cancer?

Biological factors such as heredity and external environment are probably playing big role in the development of cancer. Knowing what happens in cancer cells chemical reactions it may be possible to create molecules to interrupt these reactions and develop cancer resistance in cells.

How do molecules provide communication in living cells?

Molecules are used to alert cells desired shape, when through the "fitting" in the form of complementarity, the message is transmitted. Protein molecules are the most important, so the way they fold determines their appearance [conformation]. Therefore, a deeper knowledge of the protein fold will help resolve the issue of communication.

Where on molecular level is cell aging determined?

Another biochemical problem of aging may be related to the DNA and proteins involved in repairing DNA that is truncated during repeated replication (see: List of Ideas, 9. Genetic Technologies).

How does a whole organism develop from a single fertilized egg?

This question seems to be answered as soon as the main problem of Chap. 4: what is the structure and purpose of the proteome? Of course, each organism has its own characteristics in the organization of proteins and their purpose, but it will certainly be possible to find a lot in common.

What causes mass extinctions?

Over the past 500 million years, the complete extinction of species has occurred five times. Science continues to search for the reasons for this. The last extinction, which happened 65 million years ago, at the turn of the Cretaceous and Tertiary periods, is associated with the disappearance of dinosaurs. As David Rope poses the question in Extinction: Genes or Luck? (See: Sources for in-depth study), whether the extinction of most of the organisms living at that time was caused genetic factors Or some kind of cataclysm? According to the hypothesis put forward by the father and son, Luis and Walter, Alvarez, 65 million years ago, a huge meteorite fell to Earth (about 10 km in diameter). The impact he made raised huge clouds of dust, which became a hindrance to photosynthesis, which led to the death of many plants, and therefore, those that make up one food chain animals, down to the huge but vulnerable dinosaurs. Confirmation of this hypothesis is a large meteorite crater discovered in the southern part of the Gulf of Mexico in 1993. Is it possible that previous extinctions were the result of similar collisions? Research and debate continues.

Were dinosaurs warm-blooded or cold-blooded?

British anatomy professor Richard Owen coined the concept of "dinosaur" (which means "terrible lizards") in 1841, when only three incomplete skeletons were found. The British animal artist and sculptor Benjamin Waterhouse Hawkins took up the reconstruction of the appearance of extinct animals. Since the first specimens found had iguana-like teeth, his stuffed animals looked like huge iguanas, causing quite a stir among visitors.

But lizards are cold-blooded reptiles, and therefore at first they decided that dinosaurs were the same. Then several scientists suggested that at least some dinosaurs were warm-blooded animals. There was no evidence until 2000, when a fossilized dinosaur heart was discovered in South Dakota. Having a four-chambered device, this heart confirms the assumption of warm-blooded dinosaurs, since there are only three chambers in the heart of lizards. However, more evidence is needed to convince the rest of the world of this assumption.

What is the basis of human consciousness?

Being a subject of study of the humanities, this issue is far beyond the scope of this book, but many of our scientific colleagues undertake to study it.

As one would expect, there are several approaches to the interpretation of human consciousness. Reductionists argue that the brain is great multitude interacting molecules and that in the end we will unravel the rules of their work (see the article by Crick and Koch "The problem of consciousness" [In the world of science. 1992. No. 11–12]).

Another approach goes back to quantum mechanics. According to him, we are not able to comprehend the nonlinearity and unpredictability of the brain until we understand the connection between the atomic and macroscopic levels of the behavior of matter (see the book by Roger Penrose The New Mind of the King: On Computers, Thinking and the Laws of Physics [M., 2003]; a See also Shadows of the Mind: In Search of a Science of Consciousness [M., 2003]).

According to a long-standing approach, the human mind has a mystical component that is inaccessible to scientific explanation, so that science is not able to comprehend the human consciousness at all.

In connection with Stephen Wolfram's recent work on creating ordered images by constantly using the same simple rules(see ch. 5) should not be surprised that this approach used in relation to human consciousness; this will give you another point of view.

What causes big changes in the Earth's climate, like global warming and ice ages?

Ice ages, characteristic of the Earth for the last 35 million years, occurred approximately every 100 thousand years. Glaciers are advancing and receding across the northern temperate zone, leaving memorable signs in the form of rivers, lakes and seas. 30 million years ago, when dinosaurs roamed the Earth, the climate was much warmer than today, so trees grew even close to North Pole. As already mentioned in Chap. 5, the temperature of the earth's surface depends on equilibrium state incoming and outgoing energies. Many factors affect this balance, including the energy radiated by the Sun, the debris in space that the Earth makes its way between, incident radiation, changes in the Earth's orbit, atmospheric changes, and fluctuations in the amount of energy radiated by the Earth (albedo).

This is the direction in which research is being conducted, especially in view of the recent times controversy over the greenhouse effect. There are many theories, but there is still no true understanding of what is happening.

Is it possible to predict volcanic eruptions or earthquakes?

Some volcanic eruptions are predictable, such as the recent (1991) eruption of Mount Pinatubo in the Philippines, but others are inaccessible to modern means, still taking volcanologists by surprise (such as the eruption of Mount St. Helens, Washington, May 18, 1980). Many factors cause volcanic eruptions. There is no single theoretical approach that would be true for all volcanoes.

Earthquakes are even harder to predict than volcanic eruptions. Some well-known geologists even doubt the ability to make a reliable forecast (see: List of ideas, 13. Earthquake prediction).

What happens in the earth's core?

The two lower shells of the Earth, the outer and inner core, are inaccessible to us due to their deep occurrence and high pressure, which excludes direct measurements. Geologists obtain all information about the earth's cores on the basis of observations of the surface and the overall density, composition and magnetic properties, as well as research using seismic waves. It also helps to study iron meteorites due to the similarity of the process of their formation with the earth. Recent results obtained using seismic waves have revealed different speed waves in north-south and east-west directions, indicating a layered solid inner core.

Are we alone in the universe?

Despite the absence of any experimental evidence of the existence of extraterrestrial life, theories in this regard are plentiful, as well as attempts to detect news from distant civilizations.

How do galaxies evolve?

As already mentioned in ch. 6, Edwin Hubble classified everything known galaxies according to their appearance. Despite the careful description of their current state, this approach does not allow us to understand the evolution of galaxies. Several theories have been put forward to explain the formation of spiral, elliptical, and irregular galaxies. These theories are based on the physics of gas clouds that preceded galaxies. Supercomputer simulations have made it possible to understand something, but have not yet led to a unified theory of galaxy formation. The creation of such a theory requires additional research.

Are Earth-like planets common?

Mathematical models predict the existence of Earth-like planets from units to millions within the Milky Way. Powerful telescopes have discovered more than 70 planets outside the solar system, but most of them are Jupiter-sized or larger. As telescopes improve, it will be possible to find other planets, which will help determine which of the mathematical models more true to reality.

What is the source of the Y bursts?

About once a day, the strongest γ-radiation is observed, which often turns out to be more powerful than all the others taken together (γ-rays are similar to visible light, but they have a much higher frequency and energy). This phenomenon first recorded in the late 1960s but not reported until the 1970s as all sensors were used to monitor compliance with the ban on holding nuclear testing.

At first, astronomers believed that the sources of these emissions were within the Milky Way. The high intensity of the radiation caused an assumption about the proximity of its sources. But as data accumulated, it became obvious that these ejections came from everywhere, and were not concentrated in the plane of the Milky Way.

A flare recorded in 1997 by the Hubble Space Telescope indicated that it was coming from the periphery of a faintly glowing galaxy several billion light-years away. Because the source was far from the center of the galaxy, it was unlikely to be a black hole. These bursts of γ-radiation are believed to come from ordinary stars contained in the disk of the galaxy, possibly due to the collision of neutron stars or other celestial bodies still unknown to us.

Why is Pluto so strikingly different from all other planets?

The four inner planets - Mercury, Venus, Earth and Mars - are relatively small, rocky and close to the Sun. The four outer planets - Jupiter, Saturn, Uranus and Neptune - are large, gaseous, and distant from the Sun. Now about Pluto. Pluto is small (like the inner planets) and distant from the Sun (like outer planets). In this sense, Pluto falls out of general series. It orbits the Sun near a region called the Kuiper Belt, which contains many bodies similar to Pluto (some astronomers call them Plutino).

Recently, several museums have decided to remove Pluto's planetary status. Until more other Kuiper belt bodies can be mapped, the controversy surrounding Pluto's status will not subside.

What is the age of the universe?

The age of the universe can be estimated in several ways. In one way, the age of chemical elements in the composition of the Milky Way is estimated from the results radioactive decay elements with known half-lives based on the assumption that elements are synthesized (inside supernovae of large stars) at a constant rate. According to this method, the age of the Universe is determined to be 14.5±3 billion years.

Another method involves estimating the age star clusters based on some assumptions about the behavior and removal of clusters. The age of the most ancient clusters is estimated at 11.5 ± 1.3 billion years, and for the Universe - 11–14 billion years.

The age of the Universe, determined by the rate of its expansion and the distance to the most distant objects, is 13–14 billion years. The recent discovery of the accelerated expansion of the universe (see Chapter 6) makes this quantity more uncertain.

Another method has recently been developed. space telescope Hubble, working at the limit of its capabilities, measured the temperature of the oldest white dwarfs in the M4 globular cluster. (This method is similar to estimating the time elapsed after the burning of a fire, according to the temperature of the ash.) It turned out that the age of the oldest white dwarfs is 12–13 billion years. If we assume that the first stars were formed no earlier than 1 billion years after " big bang”, the age of the Universe is 13–14 billion years, and the estimate serves as a test of indicators obtained by other methods.

In February 2003, data were obtained from the Wilkinson Microwave Anisotropy Probe (WMAP), which made it possible to most accurately calculate the age of the Universe: 13.7 ± 0.2 billion years.

Are there multiple universes?

According to one possible solution discussed in Chap. 6 of the problem of the accelerated expansion of the Universe, a set of universes is obtained, inhabiting isolated "branes" (multidimensional membranes). For all its speculation this idea gives a wide scope for all sorts of conjectures. More details about multiple universes can be found in Martin Rees's book Our Cosmic Home.

When is the Earth's next encounter with an asteroid?

Space debris is constantly hitting the Earth. And that is why it is so important to know what size celestial bodies fall on us and how often. Bodies with a diameter of 1 m enter the Earth's atmosphere several times a month. They often explode at high altitude, releasing the energy of a small atomic bomb. Approximately once a century, a body 100 m across flies to us, leaving behind great memory(noticeable impact). After the explosion of such a celestial body in 1908 over the Siberian taiga, in the basin of the Podkamennaya Tunguska River [Krasnoyarsk Territory], trees were felled over an area of ​​about 2 thousand km 2 .

The impact of a celestial body with a diameter of 1 km, which happens once every million years, can lead to enormous destruction and even cause climate change. A collision with a celestial body 10 km across probably led to the extinction of dinosaurs at the turn of the Cretaceous and Tertiary epochs 65 million years ago. While a body of this size might only appear once every 100 million years, steps are already being taken on Earth to avoid being caught off guard. The Near-Earth Objects (NEOs) and the Near-Earth Asteroid Observation (NEAT) projects are being developed to track 90% of asteroids larger than 1 km by 2010, total number which, according to various estimates, is in the range of 500-1000. Another program, Spacewatch, run by the University of Arizona, is monitoring the sky for possible Earth impact candidates.

For more information, please visit the World Wide Web: http://neat.jpl . nasa. gov, http://neo.jpl.nasa.gov and http://apacewatch.Ipl. arizona. edu/

What happened before the Big Bang?

Since time and space trace back to the "big bang", the concept of "before" does not make any sense. This is tantamount to asking what is north of the North Pole. Or, as the American writer Gertrude Stein would put it, there is no "then" next. But such difficulties do not stop theorists. Perhaps before the "big bang" time was imaginary; probably there was nothing at all, and the Universe arose from a vacuum fluctuation; or there was a collision with another "brane" (see the question about multiple universes raised earlier). Such theories are hard to come by. experimental confirmation, because the huge temperature of the initial fireball did not allow the creation of any atomic or subatomic formations that could exist before the beginning of the expansion of the Universe.

Notes:

Occam's razor - the principle that everything should be sought for the simplest interpretation; most often this principle is formulated as follows: "Unnecessarily one should not affirm much" (pluralitas non est ponenda sine necessitate) or: "What can be explained by less should not be expressed by more" (frustra fit per plura quod potest fieri per pauciora ). The wording “Entities should not be multiplied unnecessarily” (entia non sunt multiplicandasine necessitate), usually cited by historians, is not found in the writings of Ockham (these are the words of Duran from Saint-Pourcin, c. 1270–1334 - a French theologian and a Dominican monk; a very similar expression for the first time found in the French Franciscan friar Odo Rigaud, circa 1205–1275).

The so-called topological tunnels. Other names for these hypothetical objects are Einstein-Rosen bridges (1909–1995), Podolsky (1896–1966), Schwarzschild throats (1873–1916). Tunnels can connect both separate, arbitrarily distant regions of the space of our Universe, and regions with different moments of the beginning of its inflation. Currently, the discussion continues about the feasibility of tunnels, about their patency and evolution.

Kuiper Gerard Peter (1905–1973) – Dutch and American astronomer The satellite of Uranus - Miranda (1948), the satellite of Neptune - Nereid (1949), carbon dioxide in the atmosphere of Mars, the atmosphere of Saturn's satellite Titan were discovered. Compiled several detailed atlases of photographs of the moon. Revealed a lot double stars and white dwarfs.

A satellite named in memory of the initiator of this experiment - astrophysicist David T. Wilkinson. Weight 840 kg. Byt was launched in June 2001 into a near-solar orbit, to the Lagrange point L2 (1.5 million km from the Earth), where gravitational forces The Earth and the Sun are equal to each other and the conditions for precision observations of the entire sky are the most favorable. From the Sun, the Earth and the Moon (the closest sources of thermal noise) the receiving equipment is protected by a large round screen, on the illuminated side of which are placed solar panels. This orientation is maintained throughout the flight. Two receiving mirrors with an area of ​​1.4x1.6 m, placed "back to back", scan the sky away from the orientation axis. As a result of the rotation of the station around own axis 30% viewed per day celestial sphere. WMAP resolution is 30 times higher than the previous COBE (Cosmic Background Explorer) satellite, launched by NASA in 1989. The size of the measured cell in the sky is 0.2x0.2°, which immediately affected the accuracy heavenly cards. The sensitivity of the receiving equipment has also increased many times over. For example, an array of COBE data obtained over 4 years is collected in a new experiment in just 10 days.

For several seconds, a dazzling bright fireball was observed moving across the sky from the southeast to the northwest. On the path of the car, which was visible over a vast area Eastern Siberia(within a radius of up to 800 km), a powerful dust trail remained, which persisted for several hours. After the light phenomena, an explosion was heard at a distance of over 1000 km. In many villages, the shaking of the soil and buildings was felt, similar to an earthquake, window panes were shattered, household utensils fell from the shelves, hanging objects swayed, etc. Many people, as well as domestic animals, were knocked down by an air wave. Seismographs in Irkutsk and in a number of places in Western Europe registered seismic wave. aerial blast wave was recorded on barograms obtained at many Siberian meteorological stations, in St. Petersburg and a number of meteorological stations in Great Britain. These phenomena are most fully explained by the comet hypothesis, according to which they were caused by an invasion of earth's atmosphere a small comet moving from space speed. According to modern concepts, comets consist of frozen water and various gases with admixtures of inclusions of nickel iron and rocky matter. G. I. Petrov in 1975 determined that the "Tunguska body" was very loose and no more than 10 times the air density at the Earth's surface. It was a loose snowball with a radius of 300 m and a density of less than 0.01 g/cm. At an altitude of about 10 km, the body turned into a gas that dissipated in the atmosphere, which explains the unusual bright nights in Western Siberia and in Europe after this event. Fallen to the ground shock wave caused the forest to fall.

Stein Gertrude (1874–1946) – American writer, literary theorist!. Modernist. Formally - experimental prose ("Becoming Americans", 1906-1908, published 1925) in line with literature! "stream of consciousness". Biographical book The Autobiography of Alice B. Toklas (1933). Stein owns the expression "lost generation" (in Russian: Stein G. Autobiography of Alice B. Toklas. St. Petersburg, 2000; Stein G. Autobiography of Alice B. Toklas. Picasso. Lectures in America. M., 2001).

A hint of the words there is no there, there from chapter 4! 1936 story (published 1937) Biography of Everyone, a sequel to her famous novel The Autobiography of Alice B. Toklas.

Below is a list unsolved problems of modern physics. Some of these problems are theoretical. This means that existing theories are unable to explain certain observed phenomena or experimental results. Other problems are experimental, which means that there are difficulties in creating an experiment to test a proposed theory or to study a phenomenon in more detail. The following problems are either fundamental theoretical problems or theoretical ideas for which there is no experimental evidence. Some of these issues are closely related. For example, extra dimensions or supersymmetry can solve the hierarchy problem. It is believed that full theory quantum gravity is able to answer most of the above questions (except for the problem of the island of stability).

• 1. quantum gravity. Can quantum mechanics and general relativity be combined into a single self-consistent theory (perhaps this is quantum field theory)? Is spacetime continuous or is it discrete? Will a self-consistent theory use a hypothetical graviton, or will it be entirely a product of the discrete structure of space-time (as in loop quantum gravity)? Are there deviations from the predictions of general relativity for very small scales, very large scales, or other extreme circumstances that follow from the theory of quantum gravity?
• 2. Black holes, disappearance of information in a black hole, Hawking radiation. Do black holes produce thermal radiation how does the theory predict? Does this radiation contain information about their internal structure, as suggested by the gravity-gauge invariance duality, or not, as follows from Hawking's original calculation? If not, and black holes can continuously evaporate, then what happens to the information stored in them (quantum mechanics does not provide for the destruction of information)? Or will the radiation stop at some point when there is little left of the black hole? Is there any other way to research them internal structure if such a structure even exists? Does the law of conservation of baryon charge hold inside a black hole? The proof of the principle of cosmic censorship is unknown, as well as the exact formulation of the conditions under which it is fulfilled. There is no complete and complete theory of the magnetosphere of black holes. The exact formula for calculating the number is unknown different states a system whose collapse leads to the formation of a black hole with a given mass, angular momentum, and charge. The proof in the general case of the "no-hair theorem" for a black hole is unknown.
• 3. Dimension of space-time. Are there additional dimensions of space-time in nature, in addition to the four known to us? If yes, what is their number? Is the dimension "3+1" (or higher) an a priori property of the universe, or is it the result of other physical processes, as suggested, for example, by the theory of causal dynamic triangulation? Can we experimentally "observe" higher spatial dimensions? Is the holographic principle correct, according to which the physics of our "3 + 1" -dimensional space-time is equivalent to the physics on a hypersurface with a dimension of "2 + 1"?
• 4. Inflationary model of the Universe. Is the cosmic inflation theory correct, and if so, what are the details of this stage? What is the hypothetical inflaton field responsible for rising inflation? If inflation occurred at one point, is this the beginning of a self-sustaining process due to the inflation of quantum mechanical oscillations, which will continue in a completely different place, remote from this point?
• 5. Multiverse. Are there physical reasons for the existence of other universes that are fundamentally unobservable? For example: are there quantum mechanical " alternate histories or "many worlds"? Are there "other" universes with physical laws resulting from alternative ways violations of the apparent symmetry of physical forces at high energies, located perhaps incredibly far away due to cosmic inflation? Could other universes influence ours, causing, for example, anomalies in the temperature distribution relic radiation? Is it justified to use the anthropic principle to solve global cosmological dilemmas?
• 6. The principle of cosmic censorship and the hypothesis of protection of chronology. Can singularities not hidden behind the event horizon, known as "naked singularities", arise from realistic initial conditions, or can one prove some version of Roger Penrose's "cosmic censorship hypothesis" that suggests this is impossible? Recently, facts have appeared in favor of the inconsistency of the cosmic censorship hypothesis, which means that bare singularities should occur much more often than just as extreme solutions of the Kerr-Newman equations, however, conclusive evidence for this has not yet been presented. Similarly, will there be closed timelike curves that arise in some solutions of the equations general theory relativity (and which involve the possibility of time travel in the opposite direction) are excluded by the theory of quantum gravity, which combines general relativity with quantum mechanics, as Stephen Hawking's "Chronology Defense Hypothesis" suggests?
• 7. Axis of time. What can tell us about the nature of time phenomena that differ from each other by going forward and backward in time? How is time different from space? Why are violations of CP invariance observed only in some weak interactions and nowhere else? Are violations of CP invariance a consequence of the second law of thermodynamics, or are they a separate time axis? Are there exceptions to the causality principle? Is the past the only possible one? Is the present moment physically different from the past and the future, or is it simply the result of the peculiarities of consciousness? How did people learn to negotiate what is the present moment? (See also below Entropy (time axis)).
• 8. Locality. Are there nonlocal phenomena in quantum physics? If they exist, do they have limitations in transmitting information, or: can energy and matter also move along a non-local path? Under what conditions are non-local phenomena observed? What does the presence or absence of non-local phenomena imply for the fundamental structure of space-time? How does this relate to quantum entanglement? How to interpret it from the point of view of the correct interpretation fundamental nature quantum physics?
• 9. Future of the Universe. Is the Universe heading towards a Big Freeze, Big Rip, Big Crunch or Big Rebound? Is our universe part of an endlessly repeating cyclical pattern?
• 10. Hierarchy problem. Why is gravity like this weak force? It becomes large only on the Planck scale, for particles with an energy of the order of 10 19 GeV, which is much higher than the electroweak scale (in low energy physics, an energy of 100 GeV is dominant). Why are these scales so different from each other? What prevents quantities on the electroweak scale, such as the mass of the Higgs boson, from getting quantum corrections on scales of the order of Planck's? Is supersymmetry, extra dimensions, or just anthropic fine-tuning the solution to this problem?
• 11. Magnetic monopole. Did particles exist - carriers? magnetic charge» to any past epochs with higher energies? If so, are there any to date? (Paul Dirac showed that the presence of certain types magnetic monopoles could explain charge quantization.)
• 12. The decay of the proton and the Grand Unification. How can three different quantum mechanical fundamental interactions be combined quantum theory fields? Why is the lightest baryon, which is a proton, absolutely stable? If the proton is unstable, then what is its half-life?
• 13. Supersymmetry. Is the supersymmetry of space realized in nature? If so, what is the mechanism of supersymmetry breaking? Does supersymmetry stabilize the electroweak scale, preventing high quantum corrections? Does dark matter consist of light supersymmetric particles?
• 14. Generations of matter. Is there more three generations quarks and leptons? Is the number of generations related to the dimension of space? Why do generations even exist? Is there a theory that could explain the presence of mass in some quarks and leptons in individual generations on the basis of first principles (Yukawa's theory of interaction)?
• 15. Fundamental symmetry and neutrinos. What is the nature of neutrinos, what is their mass, and how did they shape the evolution of the Universe? Why is there more matter than antimatter in the universe now? What invisible forces were present at the dawn of the universe, but disappeared from view in the process of the development of the universe?
• 16. Quantum field theory. Are the principles of relativistic local quantum field theory compatible with the existence of a nontrivial scattering matrix?
• 17. massless particles. Why don't massless particles without spin exist in nature?
• 18. Quantum chromodynamics. What are the phase states of strongly interacting matter and what role do they play in space? What is internal organization nucleons? What properties of strongly interacting matter does QCD predict? What governs the transition of quarks and gluons into pi-mesons and nucleons? What is the role of gluons and gluon interaction in nucleons and nuclei? What determines the key features of QCD and what is their relationship to the nature of gravity and spacetime?
• 19. atomic nucleus and nuclear astrophysics. What is the nature of nuclear forces that binds protons and neutrons into stable nuclei and rare isotopes? What is the reason for the connection simple particles into complex nuclei? What is the nature of neutron stars and dense nuclear matter? What is the origin of the elements in space? What are the nuclear reactions that move stars and cause them to explode?
• 20. Island of stability. What is the heaviest stable or metastable nucleus that can exist?
• 21. Quantum mechanics and the correspondence principle (sometimes called quantum chaos). Are there any preferred interpretations of quantum mechanics? How does a quantum description of reality, which includes elements such as quantum superposition of states and wavefunction collapse or quantum decoherence, lead to the reality we see? The same can be stated with the measurement problem: what is the "dimension" that causes the wave function to fall into a certain state?
• 22. physical information. Are there physical phenomena such as black holes or wave function collapse that irretrievably destroy information about their previous states?
• 23. Theory of everything ("Great Unification Theories"). Is there a theory that explains the meaning of all fundamental physical constants? Is there a theory that explains why the standard model's gauge invariance is the way it is, why the observed spacetime has 3 + 1 dimensions, and why the laws of physics are the way they are? Do “fundamental physical constants” change over time? Are any of the particles in the standard model of particle physics actually made up of other particles so strongly bound that they cannot be observed at current experimental energies? Are there fundamental particles that have not yet been observed, and if so, what are they and what are their properties? Are there unobservable fundamental forces that the theory suggests that explain other unsolved problems in physics?
• 24. Gauge invariance. Are there really non-Abelian gauge theories with a gap in the mass spectrum?
• 25. CP symmetry. Why is CP symmetry not preserved? Why does it persist in most observed processes?
• 26. Physics of semiconductors. The quantum theory of semiconductors cannot accurately calculate any of the semiconductor constants.
• 27. The quantum physics. The exact solution of the Schrödinger equation for multielectron atoms is unknown.
• 28. When solving the problem of scattering of two beams by one obstacle, the scattering cross section is infinitely large.
• 29. Feynmanium: What will happen to chemical element, whose atomic number will be higher than 137, as a result of which the 1s 1 -electron will have to move at a speed exceeding the speed of light (according to the Bohr model of the atom)? Is "Feynmanium" the last chemical element capable of existing physically? The problem may show up around element 137, where the expansion of the nuclear charge distribution reaches its final point. See article Extended periodic table elements and the Relativistic effects section.
• 30. Statistical physics. No systematic theory irreversible processes, which makes it possible to carry out quantitative calculations for any given physical process.
• 31. Quantum electrodynamics. Are there gravitational effects, caused by zero oscillations of the electromagnetic field? It is not known how when calculating quantum electrodynamics in the high-frequency region, simultaneously fulfill the conditions for the finiteness of the result, relativistic invariance, and the sum of all alternative probabilities equal to one.
• 32. Biophysics. There is no quantitative theory for the kinetics of conformational relaxation of protein macromolecules and their complexes. There is no complete theory of electron transfer in biological structures.
• 33. Superconductivity. It is impossible to theoretically predict, knowing the structure and composition of matter, whether it will pass into the superconducting state with decreasing temperature.

Actual problems mean important for this time. Once upon a time, the relevance of the problems of physics was quite different. Questions such as “why it gets dark at night”, “why the wind blows” or “why the water is wet” were solved. Let's see what scientists are racking their brains over these days.

Although we can explain more fully and in more detail the world more and more questions over time. Scientists direct their thoughts and devices into the depths of the Universe and the jungle of atoms, finding there such things that still defy explanation.

Unsolved problems in physics

Some of the topical and unresolved issues of modern physics are purely theoretical. Some problems theoretical physics simply impossible to test experimentally. Another part is questions related to experiments.

For example, the experiment does not agree with the previously developed theory. There are also applied tasks. Example: environmental problems of physics related to the search for new energy sources. Finally, the fourth group is purely philosophical problems modern science, looking for an answer to " main question the meaning of life, the universe and all that."

Dark energy and the future of the universe

According to today's ideas, the Universe is expanding. Moreover, according to the analysis of relic radiation and supernova radiation, it expands with acceleration. The expansion is driven by dark energy. dark energy is an indefinite form of energy that was introduced into the model of the universe to explain the accelerated expansion. Dark energy doesn't interact with matter in ways we know of, and its nature is a big mystery. There are two ideas about dark energy:

• According to the first one, it fills the Universe evenly, that is, it is a cosmological constant and has a constant energy density.
• According to the second, the dynamic density of dark energy varies in space and time.

Depending on which of the ideas about dark energy is correct, one can assume the future fate of the Universe. If the density of dark energy grows, then we are waiting for big gap in which all matter falls apart.

Another option - Big squeeze, when the gravitational forces win, the expansion will stop and be replaced by contraction. In such a scenario, everything that was in the Universe first collapses into separate black holes, and then collapses into one common singularity.

Many unanswered questions are related to black holes and their radiation. Read a separate one about these mysterious objects.

Matter and antimatter

Everything we see around us matter, consisting of particles. antimatter is a substance composed of antiparticles. An antiparticle is the counterpart of a particle. The only difference between a particle and an antiparticle is the charge. For example, the charge of an electron is negative, while its counterpart from the world of antiparticles, the positron, has the same magnitude. positive charge. You can get antiparticles in particle accelerators, but no one has met them in nature.

When interacting (collising), matter and antimatter annihilate, resulting in the formation of photons. Why it is matter that prevails in the Universe is a big question of modern physics. It is assumed that this asymmetry arose in the first fractions of a second after the Big Bang.

After all, if matter and antimatter were equal, all particles would annihilate, leaving only photons as a result. There are suggestions that distant and completely unexplored regions of the Universe are filled with antimatter. But whether this is so remains to be seen, having done a lot of brain work.

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Theory of everything

Is there a theory that can explain absolutely everything physical phenomena at the elementary level? Maybe there's. Another question is whether we can think of it. Theory of everything, or the Grand Unified Theory is a theory that explains the values ​​of all known physical constants and unifies 5 fundamental interactions:

• strong interaction;
• weak interaction;
• electromagnetic interaction;
• gravitational interaction;
• Higgs field.

By the way, you can read about what it is and why it is so important in our blog.

Among the many proposed theories, not one has passed experimental verification. One of the most promising directions in this matter is the unification of quantum mechanics and general relativity in theory of quantum gravity. However, these theories have different fields of application, and so far all attempts to combine them lead to a divergence that cannot be removed.

How many dimensions are there?

We are accustomed to the three-dimensional world. We can move forward and backward, up and down in the three dimensions we know, feeling comfortable. However, there is M-theory, according to which there is already 11 measurements, only 3 of which are available to us.

It's hard enough, if not impossible, to imagine. True, for such cases there is a mathematical apparatus that helps to cope with the problem. In order not to blow our minds and you, we will not give mathematical calculations from M-theory. Here is a quote from the physicist Stephen Hawking:

We are just advanced apes on a small planet with an unremarkable star. But we have a chance to comprehend the Universe. This is what makes us special.

What to say about distant space, when we know far from everything about our home. For example, there is still no clear explanation for the origin and periodic inversion of its poles.

There are many mysteries and puzzles. There are similar unsolved problems in chemistry, astronomy, biology, mathematics, and philosophy. Solving one mystery, we get two in return. This is the joy of knowing. Recall that with any task, no matter how difficult it is, they will help you cope. The problems of teaching physics, like any other science, are much easier to solve than fundamental scientific questions.