# The most essential problem of the universe, what is mass?

2020-09-02 | Science Beauty Boy Original |

What exactly is quality?

Newton's quality

Description of Newton's first law:

Any object must maintain a uniform linear motion or a static state until the external force forces it to change its motion state.

Description of Newton's second law:

The acceleration of the object is proportional to the force and inversely proportional to the mass of the object, ie F=ma, a=F/m

The two sentences are translated. Suppose there is a planet in the universe that is not affected by any force. It floats in the universe at an initial speed. If it has not been affected by any force, then the planet will move along.Moving at a uniform speed in the initial direction, the only external force that can change it. If you install an engine like the three-body engine on the planet, when the engine continues to give the planet a constant force, the effect of the force will be reflected in the speed change, The greater the force, the greater the acceleration a, and if the same force acts on a planet with a smaller mass, the acceleration will be greater. Therefore, according to Newton’s description, mass is a quantity of matter, which determines matterWhen receiving an external force, the degree of change in the state of motion, the mass maintains the original "habitual" state of matter, so the first law is also called the law of inertia. After talking for so long, Newton actually did not explain what mass is?how did it get here?

Einstein said that mass is energy

In 1905, Einstein successively published many papers on the pinnacle of Genesis, Yang Zhenning recalled:

Einstein initiated the three revolutions of the basic concepts of the physical world-time, space, energy, light, and matter.

One of the papers gave us a new understanding of quality. The title of the paper was "Is the inertia of an object related to the energy it contains?". In the paper, he himself gave an affirmative answer: The inertial mass of an object is determined by the energy contained in the object, and mass is energy. The relationship between energy and mass is the well-known mass-energy equivalent equation:

E is energy, m is mass, c is the speed of light is about 300,000 kilometers per second, which indicates that tiny mass can release huge energy. Below is the first hydrogen bomb "Mike" of mankind, tested on the islandIn the picture, the energy of this hydrogen bomb explosion is only about 500 grams of material converted into pure energy.

The composition of the substance

Actually, it is more rigorous to say that mass should be another form of energy. The equivalence of mass and energy stems from Einstein's derivation of the relationship between mass and speed in the Special Theory of Relativity, which is a result of physics and mathematics, Describes what mass is, but it has not been clear why mass is energy and what energy comes from. Therefore, we need to disassemble matter to see what is happening in the deepest part of matter.

Water is composed of water molecules, molecules are composed of atoms, and atoms are composed of nuclei and extranuclear electrons. When we continue to deepen, we will find that most of the results of atoms are empty. At the microscopic level, electrons are very far away from the nucleus.The mass is too small to be negligible. Due to the appearance of the collider, humans have discovered that although the protons and neutrons in the nucleus occupy most of the mass of matter, they are also composed of smaller particles.

Picture: Standard physical model of particles, where particles constitute everything in the universe

With the continuous progress of science and technology, more and more particles are discovered by human beings. In 2012, we discovered the Higgs boson, the source of the mass of all things.

Four Vigorous

These particles all abide by their own rules, and they will interact with the particles that they are connected to. This is the source of most of the energy of matter.

Electromagnetic interaction electromagnetic force, this is what we are most familiar with. Electrons are negatively charged and protons are positively charged. Maxwell unified electromagnetics and described that changing electromagnetics will produce changing magnetic fields, and changing magnetic fields will produce changes.Electric field, electricity and magnetism generate electromagnetic waves. Electromagnetic waves are light in a broad sense. According to the wave-particle duality, light is both a wave and a particle. Therefore, we can regard electromagnetic force as the photon in the atom being thrown around.Transmission of electromagnetic force. The main force in our daily life is electromagnetic force.

Strong interaction strong force, as we mentioned above, neutrons and protons are not the smallest particles. Each proton neutron is composed of three quarks. There is a particle that stabilizes the three quarks like glue.It is neither too close nor too far away. Electromagnetism is also called electrodynamics, and the strong interaction comes from the quantum chromodynamics between gluons and quarks, which is simply understood as quarks taking gluonsThrow it around, and then change its color when throwing gluons. This is due to the intrinsic properties of quarks. I won’t go deep here. Because of the strong force, the positively charged protons can be bundled together, and the effect is greater than the interaction between them.Repulsion, so we call it strong.

Gravity, the particles that transmit gravity-human beings are still struggling to find gravitons. You can think of gravitons as matter like two people sitting on different boats with their backs facing each other, throwing a boomerang, each timeThe effect of the dart will approach the opponent.

Weak interaction weak force. We are more familiar with weak force, which is nuclear radiation. Atoms are neutral. As many protons are positively charged, there must be as many electrons as the nucleus. When there are many atoms,The more difficult it is to confine the electrons outside the nucleus, the atom will decay. One of these decays is called beta decay. The process is that the nucleus captures the extranuclear electrons and causes a proton to change through the color of a quark and become a neutron, or a neutron releases electrons.The formation of protons requires the transfer of energy through bosons.

It can be seen that all the soldiers here are very cumbersome and laborious. Scientists think so too. Therefore, they also wonder whether they can describe the four major forces in one way, and the scientists found that the quality problem is notThese four powers are perfectly resolved.

The repulsion and adhesion between the four major interactions give everything a combined framework to form matter, but scientists use the collider to obtain the energy between the forces and convert the energy through E=mc^2When the mass is formed, it is found that the mass between the strong interactions is 1% higher, then there can only be some kind of energy in the quark, that is, the quark itself has 1% mass, then who gave this mass?

Higgs mechanism

The concept of "field" originated from the mathematician Weyl, this is the theory that was entrusted to the unified four forces, so it is called "gauge field". It can directly explain the electromagnetic field.

Yang Zhenning and Mills included the weak interaction by fine-tuning the gauge field, which is called the Yang Mills theory, and there is also a weak force field. Gellman saw the Yang Mills theory, and the inspiration flashed here.Young Mills further fine-tuned on the basis of the theory, including the strong force, and has a gluon field.

At this time, only gravitons are still described by "General Relativity", and there is a very important point. At first, everyone thought that all elementary particles are massless, and the mass comes from the field formed by fermions in bosons.In sports.

The appearance of the mass of quarks made scientists realize that particles have their own mass, and they also found that electrons and the W and Z bosons that transmit weak forces also have mass, so scientists began to think that in different fieldsIn the middle, there must be a large field continuously giving the particles mass, but it has a mechanism that makes some particles have mass and some have no mass. This mechanism is the Higgs mechanism.

In 2012, CERN discovered the Higgs boson in the collider. The simple understanding of the Higgs mechanism is like the entire universe is like the ocean full of Higgs "sea water" HiggsField, the impact of sea water gives the particles a certain amount of energy. The greater the impact the particle receives, the greater the energy obtained by the particle, and the greater the mass reflected. The photons and gluons are not affected by the sea.Therefore, photons can transmit energy and information at the most extreme speed in the universe, and their effect and size depend on the internal spin and angular momentum of the particle. Finally, mankind has found the last piece of the puzzle of the mass of all things, explaining that mass comes from energy, and energy comes fromThe particles move in the field.

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