Science is a field of human activity aimed at developing and systematizing objective knowledge about reality.
It would seem that there are no unresolved questions left for mankind, but despite the latest discoveries in various fields of science, scientists are still trying to find answers to many questions.
Our review contains ten still unsolved mysteries of science.
1. Why is matter more than antimatter
According to the modern understanding of particle physics, matter and antimatter are identical, but opposite. When they meet, they completely destroy each other and a large amount of energy is released. Most of these annihilations should have happened when the universe was just being born. Yet enough matter is left in it to create billions of galaxies, stars, planets and everything else.
Most of the discussion is around B mesons, subatomic particles with a short half-life that are composed of a quark and an antiquark. Decay of B-mesons is slower than decay of anti-B-mesons, due to which enough B-mesons could appear to form everything in the Universe. In addition, B-, D- and K-mesons can vibrate and become antiparticles and vice versa constituent particles. According to one hypothesis, mesons, in all likelihood, assume an ordinary state, which is quite possible, since there are still more ordinary particles than antiparticles.
2. Where did all the lithium go?
At the beginning of the birth of the universe, when the temperature was incredibly high, isotopes of helium, hydrogen and lithium were synthesized in huge quantities. In the Universe even now, the proportion of hydrogen and helium is very high, but the isotope of lithium-7 was found only about a third of the level predicted by modeling. There are many different explanations for why this happened, including hypotheses with hypothetical bosons known as axions. It is also speculated that they ended up in the core of stars that our current telescopes and instruments cannot detect. But a clear theory of why this happened does not yet exist.
3. Why do we sleep
Although we know that circadian rhythms (biological clocks) are responsible for wakefulness and sleep, we do not yet know the essence of this phenomenon. A person's sleep consists of several 90-minute cycles of brain activity. Each of these cycles consists of a gradual, slow immersion in a deeper sleep, and then an abrupt transition to the phase of dreams - the so-called REM or paradoxical sleep. At the end of REM sleep, the cycle either ends and we wake up, or a new cycle begins. The structure of the human brain is such that in the first half of the night, deep slow-wave sleep prevails, and by the morning the fast phase of sleep increases.
Apart from warm-blooded animals (mammals and birds), none of the living creatures have these forms of sleep. In cold-blooded vertebrates and invertebrates, the sleep period is monotonous. However, according to a number of signs, the form of sleep with different phases is very ancient. Most likely, this form of sleep provides some kind of survival advantage, since it has become entrenched in the course of evolution. But what this advantage consists in is still completely unclear.
4. What is gravity
We all know that the gravity of the moon causes the ebb and flow, the gravity of the earth keeps us on the earth's surface, the gravity of the sun keeps our planet in orbit, but how well do we understand this? Gravity affects the fact that large objects have the ability to attract smaller ones to themselves. But why does gravity exist? Why is there so much empty space in atoms? Why is the force that holds together the constituent parts of an atom different from gravity? Do particles of gravity exist? We cannot answer these questions at the current level of development of science.
5. Are we alone in the universe
The size of the universe we see is 92 billion light years, filled with billions of galaxies with stars and planets. But the only proof of life is only here on planet Earth. The likelihood that we are the only form of life in the Universe is impossibly small, but why have we not contacted anyone until now? This is called the Fermi paradox. Many suggestions have been made as to why this did not happen, and many of them seem quite plausible.
There are many scenarios, perhaps we simply do not notice the signals, perhaps they have been here for a long time, but we do not know about it, maybe they do not want to communicate with us. Or, in the most disappointing scenario, Earth is truly the only habitable planet in the universe.
6. What does dark matter consist of?
About 80% of the matter in the universe is dark matter. Dark matter is a rather strange thing as it doesn't emit any light. Although first talked about its existence about 60 years ago, there is still no evidence to support this theory.
The most natural assumption seems to be that dark matter consists of ordinary, baryonic matter, for some reason weakly interacting in an electromagnetic way and therefore not detectable in the study, for example, of emission and absorption lines. There are other candidates for the role of the composition of dark matter - these are axions, neutrinos and supersymmetric particles. But a conversation about significant candidates can be conducted on the basis of some facts obtained on the basis of observations, but there are no such facts.
7. Where are we from
Where did life on Earth come from? How did it come about? Supporters of the Primary Soup theory believe that at the dawn of its development, our fertile planet itself formed more and more complex molecules, which later gave rise to life. This could happen in the depths of the ocean, under the ice and in the craters of volcanoes. Although DNA is the predominant basis of life on Earth today, it has been suggested that RNA may have dominated early life forms.
In addition, the question arises whether other nucleic acids existed besides RNA or DNA. Did life arise only once, or did it once begin, then was destroyed and then reappeared? Some believe in pansermia, the hypothesis that life was brought to Earth with meteorites or comets in the form of microbes.
8. How plate tectonics works
It may seem surprising, but the theory of plate tectonics, moving continents and causing earthquakes, volcanic eruptions and even forming mountains, has become widely known not so long ago. Although for the first time the hypothesis that all continents could once have been a single whole was put forward as early as 1500, this idea became widespread only in the 1960s, when the theory of ocean floor spreading, based on physical evidence, appeared, according to which the blocks of the lithosphere of the oceanic crust move apart and the released space is filled with magma generated in the Earth's mantle. The mystery, however, is what exactly causes these plates to move.
9. How is the migration of animals
Many animals and insects migrate throughout the year, trying to avoid seasonal changes in temperature and the disappearance of vital food resources, or in search of a pair. Some people overcome thousands of kilometers for this and then easily find their way back. Different animals use different methods of navigation, including those that allow them to use the capabilities of the Earth's magnetic field and the internal compass. However, scientists still cannot understand the whole mechanism of these abilities, how animals know exactly where to go year after year.
10. What is dark energy
Of all the unsolved mysteries of science, dark energy may be the most mysterious. While dark matter makes up roughly 80% of the mass of the universe, dark energy is a hypothetical form of energy that scientists believe makes up 70% of the entire contents of the universe, and because of this energy, our universe continues to accelerate. So far, scientists have more questions than answers. What does it consist of? Is dark energy permanent, or can there be any changes in it? Is it possible to reconcile dark energy data with Einstein's theory of gravity, or will it need to be revised?
Back at the beginning of the 20th century, scientists believed that they had learned everything about the world order. However, this opinion was erroneous. And even now, when scientific progress has advanced far ahead, much remains far beyond the bounds of understanding.