How do bees fly? Why do some corals pulsate? What is ball lightning? Answers to these questions have already been received (or at least for the most part). It may seem to you that we know well how all the familiar things work, without exception, in the end, we encounter them every day. However, it is not.
Duct tape
If you unfold an adhesive tape (ordinary tape) in a vacuum, it will produce short flashes of X-rays. A group of scientists at the University of California for the first time noted this strange fact in 2008, although long before them, Soviet scientists observed something similar (the production of high-energy electrons, rather than x-rays) in the 50s. Then nobody found the value and did not believe it. How can duct tape produce high-energy electrons? Since then, many other scientists have repeated the focus with X-rays, so the phenomenon has gained solid ground.
We know that unrolling the ribbon increases the charge, just as a static charge accumulates if you scratch your cat with a credit card. This is called the triboelectric effect. After the charge (and the associated electric field) becomes large enough, it dramatically discharges, and the flash of electrons scatters so fast that when it enters the matter, it radiates X-rays. The problem is that we do not understand why electrons are so accelerated. The 2008 document concluded that “the energy limits and flare widths are outside of the modern theories of tribology”.
Protons
Objects familiar to us consist of atoms, and each atom consists of one or more protons. The simplest atom - the hydrogen atom - consists of one proton and one electron. A proton can be modeled as a tiny ball with a constant radius. Using data from experiments with hydrogen, scientists have calculated the radius of the proton. Currently, the most accurate estimate (the value of 2010) is 0.8775 femtometers with an accuracy of plus or minus 0.0051 femtometers. A femtometer is one quadrillion meter.
Scientists wanted to achieve less error than 0.0051, so Randolph Paul and his colleagues conducted a series of experiments with an exotic form of hydrogen called muonic hydrogen. This hydrogen is similar to normal, except that the electron is replaced by a muon, a particle that is similar to an electron, but with a much larger mass. As expected, Paul and colleagues reduced the error to 0.00067 fm, and further experiments reduced the value to an even smaller one. But what was their surprise when the final value was less than the radius of the proton itself.
Here is an analogy. Imagine that you have taken a cheap centimeter and are trying to measure them with a giant ball with a diameter of one meter with an accuracy of 0.1 meters. Now, let's say you took a giant caliper and measure it with a diameter of 0.5 meters with an error of 0.01 meters. The ball should not change the radius, depending on what you measure it. Nevertheless, this is exactly what happens with the measurement of the proton radius.
Perhaps the stated uncertainty in the 2010 CODATA value is too small? Or maybe this is a phenomenon unknown to us that has yet to be discovered?
Women
Men take the X chromosome from the mother, and the Y chromosome from the father. Women take the X chromosome from the mother and the (other) X chromosome from the father (there are other combinations, but XY and XX are the most common). In each cell of the female body there are copies of both X-chromosomes. Since 1949, the sequence of discoveries has led to the realization that one of these X chromosomes is always inactive — most of the genetic information in this X chromosome is ignored.
Suppose we have a woman's cell in which the X chromosome from her mother is inactive, and the X chromosome from her father is active. Let's call it "cage-dad." Another option would be a “mommy cell”. How does a cell decide whether to become its mom or dad cell? At first, scientists decided that the choice was completely random - almost tossing a coin was decided. But recent experiments with mice have shown that the entire body (the eye, for example) can consist mainly of mum cells or dad cells. This is not by chance. The riddle is how a cell is determined with a choice.
Animal magnetoperception
Birds do it, bees do it, even sharks in the ocean - they all sense magnetic fields. This phenomenon is known as magnetoperception (or magnetoreception). How do they do it? There are two leading hypotheses.
The first (and oldest) hypothesis is that some animals have tiny bar magnets in some of their cages. The idea is that these bar magnets line up with the earth’s magnetic field, like a compass needle, and their orientation is transmitted to the brain. And this is not a crazy idea: tiny magnets have been found in pigeon beaks. Unfortunately, they turned out to be cells of the immune system that were not able to communicate with the brain of the pigeon.
The second in the list is the hypothesis that there is a protein in the eye, which, under the action of blue light, splits into two parts that are sensitive to a magnetic field. It is possible that some animals use both mechanisms. It is also possible that there are other mechanisms. The science of animal magnetoreception is still young.
Blush
A blush is an involuntary reddening of the face associated with strong emotions or stress. It is well known that redness is associated with dilation of blood vessels (vasodilation), but what causes dilation of blood vessels?
The first guesses appeared in 1982, when Dr. Mellander discovered that facial veins have beta-adrenoreceptors in addition to the usual alpha-adrenoreceptors. These receptors can be activated by adrenaline and similar molecules associated with an emotional response. Maybe beta-adrenoreceptors in the facial veins cause blush?
In the 1990s, Peter Drummond, a professor of psychology at Murdoch University, conducted several experiments to find out. Some of his subjects took medications to block alpha-adrenoreceptors, while others were given drugs to block beta-adrenoreceptors. The doctor then subjected the subjects to stress, detested them, forced them to sing or do things that usually caused a blush. As expected, blocking alpha adrenoreceptors did not affect the redness. The blocking of beta-adrenoreceptors caused a decrease in the level of blush, but did not remove it completely. There is something else. But what?
Glass
In everyday life, glass is found everywhere: on the screens of smartphones, in bottles with water, in coffee cups, in kitchen windows. Of course, scientists and engineers are well acquainted with it. But in reality, the glass remains deeply mysterious.
The secret is in how glass is formed. You can make glass by heating a glass forming substance like silica until it melts and then let it cool. Unlike salt, for example, which transitions from a liquid to a crystalline form at a certain temperature, glass becomes more and more viscous as it cools. If the temperature is low enough, the glass will become so viscous that it hardens, although its molecules will lie far out of order. In 2007, American physicist James Langer wrote: “We do not know how transformations occur when a liquid becomes glass. We do not know whether this ordinary change of state will be a normal thermodynamic phase transition like condensation or crystallization or something completely different. ” Mysterious "glass transition" is still the subject of active research.
Allergy
In recent years, the number of children around the world with various types of allergies has increased significantly. The peanut allergy in the western hemisphere has reached a special scale - in the USA, Great Britain, Canada and in part Australia. Why?
The most common idea is the hygiene hypothesis. Some modern children grow up in a very clean environment, completely unaffected by bacteria, fungi, pollen, viruses, and other things, like children of past times. The hypothesis is that the immune system of modern "gentle" children develops differently and otherwise reacts to allergens.
Perhaps modern children do not get enough vitamin D. There are many assumptions, there are no answers.
Poison of the black widow
Black widows - spiders - are found all over the world. When they bite people, the poison often causes terrible pains all over the body, and fluctuations in blood pressure can last for a day. According to experts, "some victims even tried to kill themselves in order to stop the pain." How does poison work? Unknown.
“The dose of poison contains only a few molecules of neurotoxin, which has a fairly high molecular weight - in fact, these molecules are large enough to be seen under a conventional microscope. How can these few molecules affect an animal's body weighing hundreds or even thousands of kilograms? There is simply no concrete explanation for this mechanism. ”
Anyway, the neurotoxin must fool the body and make it harm itself. Understanding how this happens can provide answers to autoimmune disorders and other issues in which the body attacks itself.
Ice
Ice hockey players and skaters slide on ice because it is very slippery. But why is he so slippery? The same skates will not slide on the asphalt, glass or steel plate either.
The old answer indicates that the skates are putting pressure on the ice. Increased pressure reduces the melting point of ice, causing it to melt and create a thin layer of liquid water that will be slippery. The problem is that the pressure is not enough to explain the observed slip.
They offered two other answers. First, the ice melts friction. Secondly, on the border between ice and air there is always a thin layer of liquid water. There are experimental proofs of both of these answers; therefore, the participation of two of these options at once is permissible, but the relative contribution of each of them is not known for certain. Other mechanisms may be involved. Slippery ice is not the only one of the strange properties of water, there are others. For example, it has an extremely high melting point.
Substance predominance
Almost everything around us is made up of matter, but not antimatter. When antimatter is still able to be produced (with radioactive decay of certain atoms, for example, or during some thunderstorms), it usually encounters ordinary matter and quickly disappears in a flash of high-energy gamma rays.
The problem is that the best of the modern models of fundamental particle physics, the Standard Model, predicts that an equal amount of matter and antimatter should have appeared in the process of the Big Bang. However, the substance is still more. Why?
One option is that the Standard Model needs to be revised, and the already revised version will be based on the predominance of matter over antimatter. Another option - The standard model is good, but the matter and anti-matter after the explosion were separated by empty space. But what divided them? Gravity was supposed to bring them together, not to separate them.
This problem is known as the baryon asymmetry of the Universe. It remains one of the largest unsolved mysteries of modern physics.
Based on listverse.com
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