Gaussian Width
The normal density bell with an animated standard deviation — it widens and flattens as the spread grows, and spikes as it shrinks.
The normal (Gaussian) distribution centered at zero is the bell-shaped density \frac{1}{s\sqrt{2\pi}} e^{-x^2/(2s^2)} , where the standard deviation s sets the spread. Here s animates between 0.3 and 2 : as it grows the bell widens and its peak drops — the area underneath stays fixed at 1 — and as it shrinks the curve spikes into a tall, narrow concentration. This single-parameter family underlies the central limit theorem and is the maximum-entropy distribution for a fixed mean and variance; sliding s is the most direct way to feel how variance reshapes a distribution while conserving total probability.
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