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Independence of the polynomial choice in defining A^{alg}(T) (odd case)

Determine whether the algebraic K-theory class A^{alg}(T) ∈ K_1^{alg}(B M) assigned to an odd summable Fredholm module T via a polynomial function φ satisfying conditions (i)–(iii) is independent of the choice of the polynomial φ at the level of algebraic K-theory.

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Background

In the odd case, the algebraic assembly A{alg}(T) is defined using a polynomial φ applied to a projection P derived from a truncated operator. While different choices of φ yield the same class after passing to topological K-theory or Weibel’s homotopy K-theory (and hence after applying the algebraic Chern character), the independence at the level of algebraic K-theory itself is not established.

Clarifying this independence would strengthen the robustness of A{alg} and remove reliance on passage through comparison maps when working purely in algebraic K-theory.

References

Our construction of Aalg(T) depends on the choice of the polynomial φ, and it is not clear to us whether one can prove that it is independent from this choice.

Transgressing the algebraic coarse character map (2507.10816 - Engel et al., 14 Jul 2025) in Section 6.1 (Definition), Remark under the odd case