Unitary ๐^{๐}-actions with continuous spectrum
Unitary ๐^{๐}-actions with continuous spectrum
For any unitary <inline-formula content-type="math/mathml"> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="double-struck upper Z Superscript d"> <mml:semantics> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mi mathvariant="double-struck">Z</mml:mi> </mml:mrow> <mml:mi>d</mml:mi> </mml:msup> </mml:mrow> <mml:annotation encoding="application/x-tex">{\mathbb {Z}^d}</mml:annotation> </mml:semantics> </mml:math> </inline-formula>-action on a Hilbert space with continuous spectrum weakly wandering vectors are dense. This wandering can be forced to occur along โฆ