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Science

What is Quantum mechanics?

Quantum mechanics is the physics of the very small — atoms and particles — where matter behaves in strange ways: existing in multiple states at once, jumping between energy levels, and acting as both particle and wave.

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Key things to understand

  • 1Particles can exist in a 'superposition' of states until measured.
  • 2Energy comes in discrete packets called quanta, not a smooth flow.
  • 3Light and matter show both wave-like and particle-like behavior.
  • 4It's astonishingly accurate and underpins lasers, transistors, and MRI.

Frequently asked questions

What is superposition?
The ability of a quantum system to be in multiple states at once until it's measured, which collapses it to one.
Is quantum mechanics proven?
Yes — it's among the most precisely tested theories in science, despite being deeply counterintuitive.
What is wave-particle duality?
The finding that light and matter behave as both waves and particles depending on how you observe them.

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