Author: Guest Format: TextThe article about positive operators (https://ncatlab.org/nlab/show/positive+operator) defines a positive operator in terms of a positive quadratic form.
But there is no definition of a positive quadratic form. Only of positive *definite* quadratic forms.
This leaves the exactly correct definition of a positive operator UNCLEAR.
The article about positive operators (https://ncatlab.org/nlab/show/positive+operator) defines a positive operator in terms of a positive quadratic form.
But there is no definition of a positive quadratic form. Only of positive *definite* quadratic forms.
This leaves the exactly correct definition of a positive operator UNCLEAR.