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Space (mathematics)

math Maturity 7-9 Next article →

In mathematics, a space is more than just an empty area. It is a collection of objects that we call points.

Mathematical implication diagram-alt-large-print
Mathematical implication diagram-alt-large-print

These points can be many things, like numbers or even whole functions. What really matters is the structure of the space. Structure is the set of rules that defines how points relate to each other. If two spaces have the exact same relationships between their points, they are considered identical. This idea is called an isomorphism. Even if the points look different, the underlying pattern is what counts.

Spaces arrows
Spaces arrows

To understand how a space works, think about the rules you choose to follow. In one space, you might measure the exact distance between two points. In another space, like a projective space, distance might not even exist.

Spaces affine etc
Spaces affine etc

You can even have a subspace, which is a smaller part of a larger space. This smaller part must follow the same rules as the parent space. Some spaces are built to handle shapes, while others handle probability. By changing the rules, mathematicians can create entirely new worlds to study. The relationships are the most essential part of the whole thing.

For a long time, people thought space was just a way to describe the real world. Around 300 BC, a mathematician named Euclid wrote down rules for three-dimensional space.

Homothety
Homothety

He used these rules, or axioms, to build all of mathematics. Later, in 1637, René Descartes introduced a new way to use coordinates. For centuries, people believed Euclid's rules were absolute truths about our universe. They thought these rules were obvious and could not be changed. Geometry was seen as a perfect way to measure the earth.

Spaces metric etc
Spaces metric etc

Everything changed in the 1800s when mathematicians found new kinds of spaces. In 1829, Nikolai Lobachevsky explored non-Euclidean hyperbolic geometry. Around the same time, János Bolyai and Carl Friedrich Gauss also worked on these ideas.

Spaces Hilbert etc
Spaces Hilbert etc

They discovered that in some spaces, the angles of a triangle do not add up to 180 degrees. This proved that Euclid's rules were not the only way to build a space. These rules are actually hypotheses, which are ideas we test to see if they work. This discovery showed that math does not have to match our physical reality to be true.

Today, we use spaces as a powerful language to organize many different ideas. We no longer think of space as just the room around us. Instead, we see it as a mathematical structure used in many branches of math.

Spaces smooth etc
Spaces smooth etc

You might encounter Euclidean spaces, which feel like the world we know. You might also study topological spaces, which look at how things connect. Even complex ideas like infinite-dimensional function spaces use this same concept. Math uses these structures to turn hard problems into organized patterns. It is a way to find order in a huge universe of ideas.

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🖼️ Images & Media (11)
File:Mathematical implication diagram-alt-large-print.svg
Mathematical implication...
File:Homothety.svg
Homothety.svg
File:Spaces arrows.svg
Spaces arrows.svg
File:Spaces linear etc.svg
Spaces linear etc.svg
File:Spaces affine etc.svg
Spaces affine etc.svg
File:Spaces metric etc.svg
Spaces metric etc.svg
File:Spaces Hilbert etc.svg
Spaces Hilbert etc.svg
File:Spaces smooth etc.svg
Spaces smooth etc.svg
File:Spaces measurable etc.svg
Spaces measurable etc.svg
File:Spaces schemes etc.svg
Spaces schemes etc.svg
File:Spaces topoi etc.svg
Spaces topoi etc.svg
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