ON THE ISOSPECTRA AND THE ISOMETRIES OF THE ALOFF-WALLACH SPACES

  • Joe, Do-Sang (DEPARTMENT OF MATHEMATICS, EWHA WOMAN\'S UNIVERSITY) ;
  • Lee, Yoon-Weon (DEPARTMENT OF MATHEMATICS, INHA UNIVERSITY) ;
  • Park, Jin-Sung (DEPARTMENT OF MATHEMATICS, KOREA INSTITUTE FOR ADVANCED STUDY) ;
  • Ryu, Jeong-Seog (DEPARTMENT OF MATHEMATICS EDUCATION, COLLEGE OF EDUCATION, HONGIK UNIVERSITY)
  • Published : 2001.05.01

Abstract

We use the branching rules on SU(3) to show that if two Aloff-Wallach spaces $M_{k,l}\;and\;M_{k',l'}$ are isospectral for the Laplacian acting on smooth functions, they are isometric. We also show that 1 is the non-zero smallest eigenvalue among all Aloff-Wallach spaces and compute the multiplicities.

Keywords

References

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