Sharp diameter bound on the spectral gap for quantum graphs
نویسندگان
چکیده
We establish an upper bound on the spectral gap for compact quantum graphs which depends only diameter and total number of vertices. This is asymptotically sharp pumpkin chains with edges tending to infinity.
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 2021
ISSN: ['2330-1511']
DOI: https://doi.org/10.1090/proc/15090