ISU Algebra Seminar
Open Presentation by L.M. Ionescu, 11/08/2007

Rota-Baxter Algebras IV: Splitting an RBA

1. "Derived Products"
- Definition: L/R -actions of A on A+/-
- Interpretation: "vector fields" on a bundle
- RBAs, graded case: RBA <=> Im(R) subalgebra <=> A=A+ ⊕ A-. proof. ...

2. The χ map ("straightening" the direct sum decomposition)
- Theorem ∀(A,R) complete filtered RBA ∃!   χ:A1->A1 "complementing" the BCH-deformation.
    proof. ...

3. Comparing + and ⊕ (the generic star-product)
- BCH-formula is a deformation via transfer of structure, of the abelian "product" on g=A1
- The deformed convolution ∗
- Corollary (New): chi=(R⁺*R^-)^-1
- Interpretation: 1) tranzition function, 2) R-'s failure of being the convolution inverse of R+

                    (to be continued)

- Conjecture about RB-groups (factorizable groups): (A,R) complete RBA => (G=1+g, Cexp(Rχ)) is an RB-group pf. ...

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IML 11/07/2007