Amplituhedron-like geometries

A bstract We consider amplituhedron-like geometries which are defined in a similar way to the intrinsic definition of amplituhedron but with non-maximal winding number. propose that for cases minimal number points canonical form these corresponds product parity conjugate amplitudes at tree as well loop level. The superspace lifts star bosonised we give precise of. an alternative geometries, analogous original definition, and also characterisation sum over pairs on-shell diagrams use prove conjecture union all has very simple given by only physical inequalities. Although such does not positive geometry, natural extension standard form, globally oriented acts on this gives square amplitude.