Cup product on relative bounded cohomology
2
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
In this paper, we define cup product on relative bounded cohomology, and study its basic properties. Then, by extending it to a more generalized formula, we prove that all cup products of bounded cohomology classes of an amalgamated free product \( G_{1}\ast_{A}G_{2} \) are zero for every positive degree, assuming that free factors \( G_i \) are amenable and amalgamated subgroup \( A \) is normal in both of them. As its consequences, we show that all cup products of bounded cohomology classes of the groups \( \mathbb{Z} \ast \mathbb{Z} \) and \( \mathbb{Z}_{n} \ast_{\mathbb{Z}_{d}}\mathbb{Z}_m \), where \( d \) is the greatest common divisor of \( n \) and \( m \), are zero for every positive degree.
Abstract
In this paper, we define cup product on relative bounded cohomology, and study its basic properties. Then, by extending it to a more generalized formula, we prove that all cup products of bounded cohomology classes of an amalgamated free product \( G_{1}\ast_{A}G_{2} \) are zero for every positive degree, assuming that free factors \( G_i \) are amenable and amalgamated subgroup \( A \) is normal in both of them. As its consequences, we show that all cup products of bounded cohomology classes of the groups \( \mathbb{Z} \ast \mathbb{Z} \) and \( \mathbb{Z}_{n} \ast_{\mathbb{Z}_{d}}\mathbb{Z}_m \), where \( d \) is the greatest common divisor of \( n \) and \( m \), are zero for every positive degree.
참고문헌 (8)
- G. E. Bredon, "Topology and Geometry" (1993), Springer
- K. S. Brown, "Cohomology of Groups" (1994), Springer
- R. I. Grigorchuk, "Combinatorial and geometric group theory (Edinburgh, 1993)", pp.111~163 (1995), Cambridge Univ. Press
- M. Gromov, "Volume and bounded cohomology", Publ. Math. IHES, 56, pp.5~99 (1982)
- A. E. Hatcher, "Algebraic Topology" (2002), Cambridge Univ. Press
- N. Heuer, "Cup product in bounded cohomology of the free group", Ann. Sc. Norm. Super. Pisa Cl. Sci, 21(5), pp.1~26 (2020)
- N. Ivanov, "Foundations of the theory of bounded cohomology", J. Sov. Math, 37, pp.1090~1114 (1987)
- H. S. Park, "Relative bounded cohomology", Topology Appl, 131(3), pp.203~234 (2003)[DOI]
