Documentation

MIPRE.Background.Repetition.CommutingRepetition.Tracial.CStarLayer

The C*-envelope: the norm closure of the left representation's range in B(L²(M)).

Equations
Instances For

    The trace-vector state on all of B(L²(M)): φ(T) = ⟪Ω_τ, T Ω_τ⟫. On the envelope it extends M.τ.

    Equations
    Instances For

      The trace-vector state is positive: φ(T*T) = ‖T Ω‖² ≥ 0.

      Traciality on the envelope (density + continuity): for T, S ∈ envAlg, φ(TS) = φ(ST).

      The trace inequality (the boundedness engine for the right regular representation): for U, T in the envelope, ‖(U T) Ω‖ ≤ ‖T‖ · ‖U Ω‖. Traciality moves the T-square to the other side (φ(T* U*U T) = φ(U*U · TT*)), the C*-gap ‖TT*‖·1 − TT* has a CFC.sqrt in the envelope (cfc_mem on the closed star subalgebra), and positivity of the state on envelope squares finishes.

      Evaluation at the trace vector, as a linear map on B(L²(M)).

      Equations
      Instances For

        The envelope orbit of the trace vector: {S Ω ∣ S ∈ envAlg}, a dense submodule of L²(M) (it contains the range of M.ι).

        Equations
        Instances For
          theorem CommutingRepetition.StdTracialAlgebra.rightMul_welldef (M : StdTracialAlgebra) {P Q T : M.H →L[] M.H} (hP : P M.envAlg) (hQ : Q M.envAlg) (hT : T M.envAlg) (hPQ : P M.traceVector = Q M.traceVector) :
          (P * T) M.traceVector = (Q * T) M.traceVector

          Well-definedness of right multiplication on the orbit: if two envelope elements agree at the trace vector, so do their right translates (the trace inequality applied to the difference).

          A representative of an orbit element: an envelope operator whose value at the trace vector is the given vector (choice; unique up to rightMul_welldef).

          Equations
          Instances For

            Right translation on the orbit: S Ω ↦ (S T) Ω, well-defined by rightMul_welldef and bounded by the trace inequality.

            Equations
            Instances For

              The right regular representation of the envelope: the unique bounded extension of S Ω ↦ (S T) Ω along the dense orbit.

              Equations
              Instances For

                The defining property of envRight on the orbit.

                Two operators agreeing on the dense orbit are equal.

                The envelope model (Stage B, WP-B4): the C*-envelope of the left representation as a standard tracial algebra on the same GNS space. Its elements are norm limits of left multiplications, its trace is the trace-vector state (tracial by density), its ι is evaluation at the trace vector (dense by M.ι_dense), its left representation is the subalgebra inclusion, and its right representation is the extended right regular representation envRight. Continuous functional calculus operates on its elements through B(L²(M)) with cfc_mem keeping outputs in the envelope — the algebra in which the resolver-corner construction (nodes 1.2.5.x) runs.

                Equations
                • One or more equations did not get rendered due to their size.
                Instances For

                  The envelope trace extends the original trace through the left representation.