"spectral theory" meaning in English

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  "lang_code": "en",
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        "Those theories extending the eigenvalue and eigenvector theory of a single square matrix to a much broader theory of the structure of operators in a variety of mathematical spaces."
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        [
          "mathematics",
          "mathematics"
        ],
        [
          "eigenvalue",
          "eigenvalue"
        ],
        [
          "eigenvector",
          "eigenvector"
        ],
        [
          "square matrix",
          "square matrix"
        ],
        [
          "operator",
          "operator"
        ]
      ],
      "raw_glosses": [
        "(mathematics) Those theories extending the eigenvalue and eigenvector theory of a single square matrix to a much broader theory of the structure of operators in a variety of mathematical spaces."
      ],
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        "mathematics",
        "sciences"
      ]
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  "word": "spectral theory"
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        "Those theories extending the eigenvalue and eigenvector theory of a single square matrix to a much broader theory of the structure of operators in a variety of mathematical spaces."
      ],
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          "mathematics",
          "mathematics"
        ],
        [
          "eigenvalue",
          "eigenvalue"
        ],
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          "eigenvector"
        ],
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          "square matrix",
          "square matrix"
        ],
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          "operator",
          "operator"
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        "(mathematics) Those theories extending the eigenvalue and eigenvector theory of a single square matrix to a much broader theory of the structure of operators in a variety of mathematical spaces."
      ],
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        "mathematics",
        "sciences"
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