Is $TT^*$ (or $T^*T$) densely defined if $T$ is a densely defined and symmetric linear operator?
I feel this is untrue, but do you have a counterexample?
Thanks
2026-03-29 06:08:03.1774764483
Is $TT^*$ (or $T^*T$) densely defined if $T$ is densely defined and symmetric?
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