Superposition is a fundamental principle in quantum mechanics. It means a quantum system can exist in multiple states simultaneously until measured. For example, a qubit can be both 0 and 1 simultaneously.
 |
| Image Source: A depiction of overlapping states and interference patterns of qubit | Generated by AI |
Superposition is a fundamental rule of the Quantum world.
The concept of superposition may seem eerie and weird. It might not manifest too often in our surroundings. However, in the tiny world of atoms and the even tinier particles that make the atoms, it is quite obvious. And it is more possible for these tiny particles to exist in multiple states - like that spinning coin.
An electron, for example, can be in multiple locations or have different energies simultaneously. It's not in one definite place or with one definite energy until we measure it. Even when we measure it, its energy or state might change in the other instant. The measuring forces it to choose one state, just like the coin finally landing on heads or tails. Now, if the coin is let to spin in the air, and the force of gravity pulling it down is removed, it remains in the spinning state of superposition, indicating both head and tail at once, until it is stopped by something to measure.
Examples:
- Qubits in Quantum Computers: A qubit can be 0, 1, or both.
- Schrödinger's Cat: A thought experiment where a cat is both alive and dead until observed.