TY - JOUR ID - Dudko2024 LB - Dudko2024 AU - Dudko, Anastasia AU - Lesechko, Oleksandr AU - Pivovarchik, Vyacheslav TI - Recovering the shape of an equilateral quantum tree with the Dirichlet conditions at the pendant vertices ST - Recovering the shape of an equilateral quantum tree with the Dirichlet conditions at the pendant vertices JO - Opuscula Math. JA - Opuscula Math. JF - Opuscula Mathematica PY - 2024 VL - 44 IS - 5 SP - 689 EP - 705 DO - https://doi.org/10.7494/OpMath.2024.44.5.689 UR - https://doi.org/10.7494/OpMath.2024.44.5.689 AB - We consider two spectral problems on an equilateral rooted tree with the standard (continuity and Kirchhoff's type) conditions at the interior vertices (except of the root if it is interior) and Dirichlet conditions at the pendant vertices (except of the root if it is pendant). For the first (Neumann) problem we impose the standard conditions (if the root is an interior vertex) or Neumann condition (if the root is a pendant vertex) at the root, while for the second (Dirichlet) problem we impose the Dirichlet condition at the root. We show that for caterpillar trees the spectra of the Neumann problem and of the Dirichlet problem uniquely determine the shape of the tree. Also, we present an example of co-spectral snowflake graphs. KW - Sturm-Liouville equation KW - eigenvalue KW - spectrum KW - equilateral tree KW - caterpillar tree KW - snowflake graph KW - root KW - standard conditions KW - Dirichlet boundary condition KW - Neumann boundary condition SN - 1232-9274 ER -