Lefschetz Fixed-point Theorem - Relation To The Brouwer Fixed Point Theorem

Relation To The Brouwer Fixed Point Theorem

The Lefschetz fixed point theorem generalizes the Brouwer fixed point theorem, which states that every continuous map from the n-dimensional closed unit disk Dn to Dn must have at least one fixed point.

This can be seen as follows: Dn is compact and triangulable, all its homology groups except H0 are 0, and every continuous map f : Dn → Dn induces a non-zero homomorphism f* : H0(Dn, Q) → H0(Dn, Q); all this together implies that Λf is non-zero for any continuous map f : Dn → Dn.

Read more about this topic:  Lefschetz Fixed-point Theorem

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