대한수학회보 (Bulletin of the Korean Mathematical Society)

  • 제62권1호
  • /
  • Pages.71-80
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  • 2025
  • /
  • 1015-8634(pISSN)
  • /
  • 2234-3016(eISSN)
대한수학회 (Korean Mathematical Society)
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THE EULER CHARACTERISTIC OF THE FIBER PRODUCT OF MORSE FUNCTIONS

  • Yasuhiko Kamiyama (Department of Mathematical Sciences Faculty of Science University of the Ryukyus)
  • 투고 : 2024.01.21
  • 심사 : 2024.08.29
  • 발행 : 2025.01.31
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초록

For a Morse function f : M → ℝ on a connected closed manifold M, we denote by C(f) the fiber product of two copies of f. We prove a formula which describes χ(C(f)). As an application, we consider two Morse functions on U(n). We obtain the result that χ(C(f)) is (-2)n or a certain number which originated in dynamics.

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과제정보

The author would like to thank the referee and reviewer for carefully reading the manuscript and for valuable comments to improve it.

참고문헌

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