What is matter and antimatter asymmetry and what happens when matter and antimatter collide?

Humans can discover many things regards the origins and existence of our universe. Whenever we find an answer, more questions are raising. So, scientists throughout history had to put such an effort to uncover the secrets of the universe. But still, mysteries are present like the antimatter and the matter asymmetry.

What is Matter?

The matter is what forms the basis of objective phenomena together with energy. Matter make The observable universe. Matter forms with elementary particles known as quarks and leptons. Electrons, protons, and neutrons are upper level to quarks and leptons. Those made the atom. A large number of elements and molecules are together to make the bulk matter that we see in everyday life.

Matter has three different phases. Solids, liquids, and gas are the main phases. Other than that, there are also plasmas, foams, and clusters that don’t define clearly. Each phase has different types of matter. For example, there are crystalline or amorphous structured solids.

Regardless of phase, all matter has the property of inertia. Inertia is the resistance to velocity. Sir Isaac newton’s three laws of motion formulate and explain what Inertia is.

What is Antimatter?

Antimatter and matter have the same mass. Magnitudes for electric charge and magnetic movement are the same but opposite in sign. Each subatomic particle has corresponding antimatter.

The idea of antimatter first comes to light in theoretical analysis of the duality between the positive and negative charge. P.A.M. Dirac was the founder of antimatter. Antimatter and matter have the same mass. Magnitudes for electric charge and magnetic movement are the same but opposite in sign. Each subatomic particle has corresponding antimatter.

  • Electron: – Positron
  • Proton: – Antiproton
  • Neutron: – Antineutron

Elementary particles also have corresponding antimatters. Scientists believe that antiparticles and particles are created in equal amounts from energy. This is a theoretically claim and experiments support it. But they can’t co-exist in close range.

Scientists had to bombard protons with protons to create antiprotons. Referring to the E = mc2 formula, an incident proton should have 5.6 gigaelectron volts minimum kinetic energy for extra particles of proton mass to appear. That kind of energy wasn’t available until the 1950s. A team of scientists including some smartest physicists led by Owen Chamberlain and Emilio Segrè created antiproton. It was possible thanks to the Bevatron particle accelerator at Berkely, California.

CERN (European Council for Nuclear Research) created an antiatom for the first time in 1995. It contains an antiproton and positron orbiting around it. So, it is an antihydrogen atom.

Image of a liner accelerator
Image of a liner accelerator

What happens when matter and antimatter collide?

When antiparticles and particles are in close range, in a fraction of a second, they collide. Then a reaction called annihilate happens. A positron (e) and an electron (e+) annihilate and create Gamma (ϒ) rays. Scientists create matter and antimatter by the inverse reaction. We can apply newton’s famous equation E = mc2 for this reaction.

Antimatter created by inverse reaction can’t exist for a long time. If positrons are not moving very fast, they will be an electron and both particles will disappear creating energy. However, some scientists manage to keep positrons for 1000 seconds.

Great mysteries of the universe

If matter and antimatter were created in equal amounts why almost no antimatter can be found in our observable universe. Scientists believe that the milky way is all made of matter. This remains a puzzle in science. There are several theories explaining this mystery.

Like matter contains protons energy contains photons. Protons and photons exist in a 1:1B ratio in the universe. So, we can say a large amount of matter and antimatter collide with and are annihilated. A small number of matters left and the universe we know today was created from them. This imbalance is called antimatter and matter asymmetry. If that true big bang created an unequal amount of antimatter and matter.

Another theory says something destroys existing antimatter in the universe. It could be a cosmic accident or maybe antimatter is unstable and couldn’t last long in our universe.

If we assume antimatter and matter in an equilibrium equation, it is possible to have an imbalance between them. Like an equilibrium between 2 phases of matter. Factors like temperature decide the amounts in most cases. But the problem is almost no antimatter exist in the known universe.

Now researchers have observed certain laws of nature don’t apply to antimatter as it to matter. Scientists are encouraged to find why. Maybe oscillating particles decay into the matter more than antimatter.

Imaging spin coins. 50:50 chance for both sides. So, if billions of coins have spun theoretically 500 million heads and 500 million tails should be obtained. But if some interruptions like a marble rolling through the table while coins are spinning can add a little imbalance. This could have happened in the beginning with oscillating particles.


Antiparticles and particles are equal in terms of magnitude but opposite in sign. They disappear by colliding together and creating energy. The inverse is also possible. The existence of our universe shows the imbalance of matter and antimatter which is called asymmetry.

I hope you got to know a new thing. Stay with us to read more about science.

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