This has a counterpart, via the metric g and the Kahler relation, in the unit sphere in the linear space O spanned by the complex structures Yα ; the space O is also said to be a quaternionic structure on M , and if the Yα are unimodular then its unit sphere corresponds to unimodular complex structures in (M , g ) .
Quaternionic integrable systems
So, we introduce the real, 4-dimensional vector space V with its Lorentz metric g and preferred unit timelike vector t, on which the mass function MN becomes a real linear function.
Total Mass-Momentum of Arbitrary Initial-Data Sets in General Relativity
We characterize certain common ob jects in the theory of operator spaces (unitaries, unital operator spaces, operator systems, operator algebras, and so on), in terms which are purely linear-metric, by which we mean that they only use the vector space structure of the space and its matrix norms.
Metric characterizations II
In the present paper we give new linear-metric characterizations of unital operator spaces (or equivalently, of ‘unitaries’ in an operator space).
Metric characterizations II
Section 4) we give new linear-metric characterizations of unital operator spaces (resp. operator systems).
Metric characterizations II
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