Quantum Atom

An atom is not a tiny solar system. Quantum mechanics predicts probabilities for measurement results, not little planets on fixed tracks. This is a mathematical visualization, not a photograph. Dots map possible results for one electron, not a swarm of electrons. A denser cloud means greater probability.

• A flat cut through the 3D probability density. Dark gaps reveal nodes where the probability density is zero.
• Each dot is one position measurement on a newly prepared atom. The white ring marks the latest result.
• The cloud has no hard edge. Colours show wavefunction signs, not electric charges or visible colours. Slice brightness is nonlinear to reveal faint regions. Switching orbitals selects a prepared state; it does not simulate an excitation. The model neglects spin, relativity and interactions with other atoms. 1 a₀ ≈ 0.0529 nm.

1. 1The lowest-energy cloud is spherical. Turn on the same-scale option and compare 1s with the larger excited states.
2. 2Use the centre slice to find the dark nodes. Opposite wave signs are not opposite charges: the electron is always negatively charged.

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