Quantum World


Diagram of electrons orbiting protons and neutrons.

What is quantum physics? You might have heard the phrase used in a TV show or movie before. It's not just science fiction, however. Quantum physics is a real scientific field that has existed for over 100 years. There are a few things you need to know before learning about quantum physics.

Subatomic Particles

All matter in the universe is made of tiny particles called atoms. Atoms themselves are made of protons, neutrons, and electrons. These are called subatomic particles, "subatomic" meaning smaller than an atom.

Classical Mechanics

Diagram of a ball flying from point A to point B.

Scientists describe motion in our world with a theory called classical mechanics. Imagine tossing a ball through the air. Using classical mechanics, you can know where the ball is and how fast it's going at any time. This makes perfect sense: you can watch the ball go all the way from point A to point B. Classical mechanics applies to everything from the tiniest speck of dust to entire planets and galaxies.

When it comes to subatomic particles, things are different. Imagine tossing a ball...and having no idea where it is before it lands! These tiny particles break the most basic rules of classical mechanics. To describe how subatomic particles work, scientists came up with a new theory: quantum mechanics. Quantum mechanics is also known as quantum physics.

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