Positive eigenvalues and two-letter generalized words
نویسندگان
چکیده
A generalized word in two letters A and B is an expression of the form W = Aα1Bβ1Aα2Bβ2 · · ·AαNBβN in which the exponents are nonzero real numbers. When independent positive definite matrices are substituted for A and B, it is of interest whether W necessarily has positive eigenvalues. This is known to be the case when N = 1 and has been studied in case all exponents are positive by two of the authors. When the exponent signs are mixed, however, the situation is quite different (even for 2-by-2 matrices), and this is the focus of the present work.
منابع مشابه
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تاریخ انتشار 2002