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Bifurcation measure as the limiting root measure

Determine whether the bifurcation measure ν_bif constructed from the Lyapunov exponent of the Burau representation of random positive 3-braids gives the limiting distribution of roots of Alexander polynomials for closures of such braids; i.e., prove that ν_bif equals the almost-sure weak limit of ν_{w_n} as n→∞.

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Background

The authors define a Lyapunov exponent λ(t) for the random products of Burau matrices evaluated at t and introduce a bifurcation measure ν_bif via χ(t)=max{λ(t),log+|t|}. They then prove equidistribution of roots toward ν_bif on a subset U of the plane and conjecture ν_bif coincides with the full limiting measure of roots.

Establishing ν_bif as the global limiting measure would unify dynamical properties of the Burau representation with the statistical distribution of Alexander polynomial roots and fully resolve Conjecture 1 with an explicit candidate for ν∞.

References

In the spirit of Deroin and Dujardin, we conjecture that the bifurcation measure gives the limiting measure for such roots, and prove this on a region with positive limiting mass.

Roots of Alexander polynomials of random positive 3-braids (2402.06771 - Dunfield et al., 9 Feb 2024) in Abstract; also Subsection “Lyapunov exponents and bifurcation measures” in the Introduction