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The field of physics has always strived to discover the truth lying behind the complicated yet smooth functioning of nature. It has always brought to light some amazing explanations, theories and proven them beautifully in many cases. The discovery of positron is also one of the great achievements that inspire innovative theories and thinking continually, and is a lot beyond the reception of human senses.

What Exactly Is a Positron?

We exist in a world made up of matter. We define matter as something that has mass and occupies space. But truly speaking, that isn’t the best definition, especially when we bring into the picture what we call “Antimatter.” Antimatter, just like matter, has mass and also occupies space. We have an antimatter counterpart for every matter we see around, or more specifically speaking, for the fundamental particles that make up the material world around us. To note, a positron is the antimatter of electron.

Then how do we distinguish between a matter and its corresponding antimatter, or more particularly, between an electron and a positron? Do they have different mass? No, antimatter of a given fundamental particle has exactly the same mass as the fundamental particle itself. So, an electron and a proton have the same mass. Their charges, however, differ in sign. Also, they are like the mirror images of each other.

Thus, positron is a positively charged mirror image of an electron. It has the same mass as the electron. But does this similarity actually make a difference? Is it something really too far in relation with an electron? The existence of antimatter is as much logical as the existence of matter. Going back to the complete basics, we find that the sign of charges was just a convention. Also, being the mirror image of a particle won’t contribute much to the difference between the behaviour of the two, electron and positron. This makes “matter” and “antimatter” just a convention to differentiate two (almost) identical twins by different names. It’s like, there could entirely exist a world made of antimatter and the people there might just be wondering about their antimatter, which is matter for us.

If you put a positron in an electric field, it would move in the direction opposite to that an electron would have. A positron also has wave-particle duality. The best of all facts is perhaps that when an electron comes in contact with positrons, they annihilate, i.e. they completely get converted into energy. There remains no more electron or positron anymore. Annihilation is a process common for all matter-antimatter pairs – matter comes closer to corresponding antimatter, both blast out giving out gamma rays as energy. Wonderful, isn’t it?

Positron, predicted by Dirac in 1928, and discovered by Carl D. Anderson in 1932, is sometimes generated naturally and can be produced artificially, by radioactive decay of certain isotopes like carbon-11, potassium-40, aluminium-26, iodine-121, etc. After Anderson discovered positrons in cosmic rays, Frederic and Irene Joliot-Curie discovered, observed them when they bombarded Aluminium with alpha particles. The couple also won a Noble Prize for it.

The antimatter for heavier particles like proton is not much spoken of. Higher mass certainly means too much of energy required to produce them. Also, they are short-lived because of the matter world around us – they would easily annihilate. Particles with too low mass are expected to have relatively stable antimatter and indeed, positrons, antineutrino, etc. have been discovered well. They are; thus, expected to span and predict a wide possibility of antimatter world.

We hope the above article must have bolstered your interest in physics. Here’s some more for you: Top 5 discoveries in Physics that will blow your mind. Enjoy 🙂

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