Characteristic class

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Notion

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Science and technology

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What Wikipedia says

In mathematics, a characteristic class is a way of associating to each principal bundle of a topological space X a cohomology class of X. The cohomology class measures the extent to which the bundle is "twisted" and whether it possesses sections.

Excerpt from the Wikipedia article “Characteristic class”, under the CC BY-SA 4.0 license. Read the article on Wikipedia