Dalam matematika, dua operator linear disebut isospektral atau kospektral jika mereka memiliki spektrum yang sama. Secara keseluruhan, mereka memiliki beberapa set dari nilai eigen, saat itu dihitung dengan multiplisita.

Teori operator isospektral bergantung pada tanda yang berbeda pada apakah ruang tersebut adalah dimensi terbatas atau tak terbatas. Dalam dimensi terbatas, hal tersebut secara esensial sejalan dengan matriks-matriks persegi.

Referensi

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