The double-slit experiment is a classic demonstration of wave-particle duality in physics. Here’s a simplified explanation:

1. Setup: Imagine a light source, a screen with two parallel slits, and a detection screen behind the slits.
2. Experiment: When light passes through the slits, it creates an interference pattern on the detection screen, indicating wave-like behavior. The light waves passing through the slits interact, resulting in regions of constructive and destructive interference.
3. Particle behavior: If you try to observe the light as it passes through the slits by shining a separate light on the slits, the interference pattern disappears, and two distinct patterns emerge, indicating particle-like behavior (like bullets passing through the slits).
4. Observer effect: The act of observation itself determines whether light exhibits wave-like or particle-like behavior. If unobserved, light behaves like a wave; if observed, it behaves like particles (photons).
5. Quantum implications: This experiment demonstrates the principles of quantum mechanics, including wave-particle duality, superposition, and the observer effect. It shows that, at the atomic and subatomic level, particles can exhibit both wave-like and particle-like properties depending on how they’re observed.

The double-slit experiment has been performed with various particles, including electrons, neutrons, and even atoms, consistently demonstrating the strange implications of quantum mechanics.