How to deduce that the universe is a vacuum, and whether the universe is a vacuum?

If you think about it, you can also know: you should always know why the air on the plateau is thinner, the higher you go, the thinner the air becomes, so when you go far into the universe, the air is negligible? In fact, the most essential reason is that the gravitational effect of the earth attracts the gas in the cosmic space to its surroundings, so the earth has an atmosphere, which is also the reason why each celestial body has its own atmosphere, but there is no gas in the cosmic space.

Speaking of which, thank you to Newton! Because it was he who discovered the theory of "universal gravitation", and it was this theory that made people know that the universe is almost vacuum.

Through a variety of detection and observation data.

Learn to make analogies, and you'll find that you can prove a lot of things yourself!

Proof: 1You have been in the car, the faster the car, the stronger the wind in front of you, I believe you should have experienced;

2.The general speed of the car is only tens of kilometers per hour, which is far less than the speed of the earth in the universe of tens of kilometers per second;

3.It is not a vacuum, i.e. the presence of air, that is the condition for the formation of winds on Earth.

With the anyway method: from condition 3, you might as well assume that the universe is not a vacuum, then according to conditions 1 and 2, you can push out that you should be able to feel a very strong wind coming on, but the actual experience tells you that there is no such wind, so the universe is vacuum, at least almost vacuum!

When scientists came up with the idea that the universe was a vacuum, it was uncertain whether anyone had ever been to heaven.

On the contrary, it is precisely because the vacuum cannot transmit sound, and if the sound cannot be heard, it means that it is a vacuum.

The estimated figure for the first floor is too small, and the real figure may be 1,000,000 times his estimate.

The universe is not a pure vacuum. Based on the available data, it is estimated that there are 10 protons to the power of 78 and 10 to the power of 88 photons in the universe.

Because the higher the altitude on Earth, the thinner the air.

Until we find out what the specific matter is in space, we can only say that it is a vacuum.

The spacecraft is lifted off by the thrust of the launch vehicle from the ground to the orbit stage; The spacecraft operates in orbit by inertia; The orbit change of the spacecraft is achieved by starting the orbit change rocket on the spacecraft.

The principle of operation of rockets, whether in the atmosphere or in a vacuum, works according to the "principle of conservation of momentum", that is: mass velocity (of the rear jet) = mass (forward) velocity of the (spacecraft).

Not an absolute vacuum, just an approximate vacuum. Space cannot transmit sound.

In the vast space of the universe, in addition to various stars, there is a lot of matter, and what we call space is not an absolute vacuum. Scientists have observed the presence of gas, dust, and clouds between the stars, collectively known as interstellar matter.

The total mass of interstellar matter accounts for about 10 of the total mass of the Milky Way, which is not small in terms of numbers. However, due to the vastness of the Milky Way, the density of interstellar matter is particularly small, averaging 10-12 grams cm3, which is equivalent to 1 hydrogen atom per cubic centimeter. This density is a high vacuum that is far from being reached in laboratories on Earth, with the highest vacuum currently being 10-12 mm of mercury, equivalent to 10,000 particles per cubic centimeter.

The temperature of interstellar matter varies greatly, with low temperatures of only a few degrees and bases close to absolute zero; The high ones can reach tens of millions of degrees.

Interstellar matter is unevenly distributed within the Milky Way. The density of interstellar matter varies greatly between regions, from interstellar gas and dust to interstellar clouds when they aggregate into a density of more than 10 103 particles per cubic centimeter, and intercloud densities as low as particles per cubic centimeter. Interstellar matter is concentrated in the galactic spiral arms.

Interstellar gases include gaseous atoms, molecules, ions, electrons, etc., and the elemental abundance of interstellar gases is similar to that of the universe, with hydrogen being the most, helium being the second, and other elements being very low. This is related to the origin and evolution of the elements, and also indicates the unity of matter in the universe.

Interstellar dust is solid particles 10-5 10-6 cm in diameter, dispersed in interstellar gas. The total mass of interstellar dust accounts for about 10 of the total mass of interstellar matter. Interstellar dust may be composed of ice-like substances such as water, ammonia, and methane, minerals such as silica, magnesium silicate, and ferric oxide, as well as graphite grains.

Interstellar dust scatters starlight and weakens it, a phenomenon called interstellar extinction. Interstellar dust has a great influence on the formation of interstellar molecules, on the one hand, it prevents the ultraviolet radiation of starlight from dissociating interstellar molecules, and on the other hand, it acts as a catalyst to accelerate the formation of interstellar molecules.

Interstellar matter can be searched for by measurements of the electromagnetic spectrum. Interstellar ions were first discovered in 1904, the presence of interstellar dust was confirmed by the observation of distant stars turning red in 1930, and the presence of 105 107 high-temperature gases was confirmed in 1977.

According to modern theories of stellar evolution, interstellar matter aggregates into early stars, which in turn send matter into interstellar space through explosions, ejections, and loss.

It can be approximated that the universe is vacuum.

From a mechanical point of view, as long as the pressure is less than one standard atmosphere, it is a vacuum. By this definition, the universe must be vacuum.

Moreover, the vacuum of the universe is quite high, and the best instruments on earth cannot reach the vacuum level of the universe.

Most of all the atoms in the universe are vacuums, but vacuums are not really empty. According to the theory of quantum physics, vacuum fluctuations persist after the complete disappearance of light and radio waves in a vacuum. In fact, those vacuum fluctuations are essential to our existence.

Although light is an electromagnetic wave, unlike mechanical waves, it has wave-particle duality, and photons are a kind of particle. Space is not a vacuum, but it is generally considered a vacuum;

Thank you for asking a question [heart].

What is the singularity.

Answering a singularity is usually a point that is called undefined when it is a mathematical object, or when it is so unordered in special circumstances that it appears in a set of exceptions. Such as derivatives. The singularity is a mathematical concept that begins in calculus to refer to the point at which the condition of breaking the continuity of a function.

In physics, it refers to the point at which the curvature of space-time becomes infinity in space-time.

Space is not an absolute vacuum, but an approximate vacuum.

The meaning of vacuum refers to the state of gas with a pressure below one atmosphere in a given space and is a physical phenomenon. In the "void", sound cannot be transmitted because there is no medium, but the transmission of electromagnetic waves is not affected by the vacuum.

In fact, in vacuum technology, vacuum is aimed at the atmosphere, and when part of the matter in a particular space is expelled to make its pressure less than one standard atmosphere, we generally call this space a vacuum or vacuum state. Vacuum is often used as a unit of pressure in Pascal or Torr. In the natural environment, only outer space can be called the closest space to a vacuum.

The overall universe is an organic objective whole, and this objective whole is called "space".

The objective universe is composed of matter, matter is eternal development and change and objectively exists, the movement of objective matter also creates the objectivity and regularity of "time", there is a specific electromagnetic field in the space of a specific star, so in the objective universe, there is absolutely no physical "vacuum".

There are very few atoms or molecules in space, which is one hydrogen atom or molecule per cubic meter. In addition, there are wave substances such as photons and neutrinos.

If some air is released in space, because the main components of the air are nitrogen and oxygen, they are both molecular on Earth. When air is released into space, nitrogen and oxygen molecules in a discrete state quickly disperse. These nitrogen and oxygen molecules will also be decomposed into nitrogen and oxygen atoms or ionized by cosmic rays.

Our vacuum standard is less than one atmosphere. All other claims are rhetorical sophistry. No one has ever said that the universe is an absolute vacuum. Nor does an absolute vacuum exist in present knowledge.

The edge of the universe is an absolute vacuum, like a barrier, and there is not even space, no object can enter, and the density is infinitely small.

Outside the universe is an absolute vacuum.

The standard statement in the physics textbook of the third year of junior high school or the first year of high school: (applicable to all liquids and gases) negative pressure vacuum vacuum suction force = low pressure - high pressure strong;

Positive pressure gauge pressure = high pressure intensity - low pressure intensity;

Sometimes vacuum refers to the thinner degree of liquid or gas, the thinner it is, the lower the pressure, the greater the corresponding vacuum.

No, there are places where an atmosphere will form, and there will be air, and there will be many places in the universe, but we haven't explored it, so we can't be sure.

Not necessarily. This is because there are many unsolved mysteries in the universe, and there are many undetected places, so it is not certain whether they are all in a vacuum.

The whole universe should be in a vacuum, because we don't know much about the universe yet, so the universe should be in a vacuum now.