Triviality of a Trace on the Space of Commuting Trace-class Self-adjoint Operators
نویسنده
چکیده
In the present article, we investigate a possibility of a real-valued map on the space of tuples of commuting trace-class self-adjoint operators, which behaves like the usual trace map on the space of trace-class linear operators. It turns out that such maps are related with continuous group homomorphisms from the Milnor’s K-group of the real numbers into the additive group of real numbers. Using this connection, it is shown that any such trace map must be trivial.
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