According to popular belief, a vacuum is absolute emptiness. This is not a misunderstanding, this is the strictest definition of the term, according to which a vacuum is a region of space where matter is completely absent. The problem is that this is an ideal vacuum state, which he only strives to reach in theory. It can't exist in the real world. Even artificially, scientists cannot create such conditions in the laboratory.
In the scientific world, a vacuum usually means an empty area of space. Some of them may indeed be close to absolute emptiness. In this case, there may be only one molecule or one atom in one cubic kilometer of interstellar space.
If you look at a vacuum through the prism of quantum physics, then in the vacuum it is no longer space, but becomes a state with minimal (not completely absent) energy. This basic theory of physics assumes that in any space there are virtual particles or photons due to the uncertainty principle (even in an absolute vacuum without any waves, the electric and magnetic fields cannot be exactly zero at the same time).
They manifest as electromagnetic noise. They differ from real particles in that the connection between the energy and momentum of the virtual particles is disconnected. As a result, they have a short lifespan and disappear soon after birth. Virtual particles were invented to explain the fundamental interactions between real particles. The essence of this interaction is the exchange of virtual particles. This has helped scientists explain a number of effects, including what Hawking called black hole evaporation.
Even if we completely empty or block any space, the virtual particles will not disappear. The birth of the pairing of charged particles with antiparticles is not excluded. But if the external field around it affects the vacuum with its energy, then a true particle will appear. When interacting with vacuum, they change charge and mass. Then the vacuum itself becomes the ** of the new particle. Scientists call this phenomenon vacuum boiling and are studying it in the field of high-energy physics.
Due to the continuous birth and death of virtual particles, there will be brief energy level fluctuations in space-time. This phenomenon is called quantum vacuum fluctuations. Physicists have documented and confirmed that even in an absolute vacuum, there are oscillations of magnetic or electric fields (as a result of the uncertainty principle).
These vibrations can also be referred to as the zero-point energy of the vacuum. It is not yet possible to completely eliminate oscillations in a vacuum and the particles that produce them because they exist for an extremely short period of time – 1 femtosecond (one millionth of a billionth of a second). And they are also very small.
Achieving an absolute vacuum would not only call into question the foundations of quantum mechanics and classical physics, but would also destroy our universe. If the zero energy of the vacuum drops, the energy of the particles increases many times and causes a thermal surge**.
The cosmic vacuum will always be at its minimum. There will be no real particles or energy in it. But space-time and its inherent laws of physics will continue to exist. If you take them away, what's left?Unfortunately, there is no definition of this in physics yet.
It transcends the "nothingness" that exists in the universe and becomes a more philosophical, absolute "nothingness". It is simply not known if it has a physical meaning. Therefore, the complete removal of matter from a vacuum undermines the foundations of modern science and requires further research and understanding.