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Mathematics

Inner Product Space

Quick fact

The most famous inner product space is ℝⁿ with the dot product, but the concept extends to infinite-dimensional spaces such as L², the space of square-integrable functions, which underpins quantum mechanics.

Why this is interesting

You know the dot product from basic geometry—it measures how two arrows align. But what if you need to measure lengths and angles in a space with infinitely many dimensions, like a space of functions? That's exactly what an inner product space does.