ABSTRACT
The space that is now simply denoted H n 2 https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9781351045551/4730f38a-3e35-40e9-9674-aa9748370ac3/content/eq2395.tif"/> , first appeared in [24, 40, 41]. In [41], Lubin used this space to produce the first example of a tuple of commuting subnormal operators that does not admit a joint normal extension. Drury’s motivation in [24] was to find the correct multi-operator analogue of the von Neumann inequality for contractions.
