Realization

Definition (Realization)

Given a mapping T:J×JMp×n(R)T:J\times J\to M_{p\times n}(\mathbb{R}) we say a realization of T is any triple (A,B,C)(A,B,C) s.t. the following holds T(t,τ)=C(t)ΦA(t,τ)B(τ)T(t,\tau)=C(t)\Phi_{A}(t,\tau)B(\tau)

Proposition

For a given Weighting Pattern \exists Realizations that have different (i.e. higher) dimensions.

Definition (Realizable)

Given a mapping T:J×JMp×n(R)T:J\times J\to M_{p\times n}(\mathbb{R}) we say TT is realizable if (A,B,C)\exists(A,B,C) Continuous maps s.t. the following holds T(t,τ)=C(t)ΦA(t,τ)B(τ)T(t,\tau)=C(t)\Phi_{A}(t,\tau)B(\tau)

Theorem (Realizable ⇔ Separable)

A matrix function T:J×JMp×n(R)T:J\times J\to M_{p\times n}(\mathbb{R}) is Realizable if and only if H,G\exists H,G s.t. T(t,τ)=H(t)G(τ)T(t,\tau)=H(t)G(\tau) i.e. our Weighting Pattern is separable in the sense of differential equations.

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