I didn't see a topology forum, so I thought I'd post this question here. Can anyone give any pointers on using van Kampen's theorem? I understand the basic way it works, decompose a space X into open, path-connected sets, say U and V.(adsbygoogle = window.adsbygoogle || []).push({});

Then pi1(U) * pi1(V) = pi1(X)/N, where N is a normal subgroup. The N is what gives me trouble. How do calculate what the normal subgroup is?

Any help is appreciated!

**Physics Forums - The Fusion of Science and Community**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Van Kampen's theorem and fundamental groups

Loading...

Similar Threads - Kampen's theorem fundamental | Date |
---|---|

A Cubic quartets? | Feb 15, 2018 |

B Fermat's Last Theorem; unacceptable proof, why? | Feb 15, 2018 |

A Newton's Generalized Binomial Theorem | Sep 29, 2017 |

I Fundamental elements transformation | May 29, 2017 |

I Question about the Fundamental Theorem of Algebra | May 20, 2017 |

**Physics Forums - The Fusion of Science and Community**