Julien Sedro

I am a post-doc at LPSM. I am part of the ERC project SOS , lead by Viviane Baladi.
From 2015 to 2018, I did my PhD at the Laboratoire Mathématique d'Orsay, under the supervision of Hans Henrik Rugh.
For further information, you may consult my resume.

Research interests

My area of research is ergodic theory, the probabilistic study of chaotic dynamical systems. More precisely, I am concerned with response problems, which is the study of the stability of statistical properties of dynamical systems, i.e. the regularity of particular invariant measures w.r.t parameters, and the computation of their derivatives, whether in an autonomous or nonautonomous context.

I also developed an interest in limit theorems for random dynamical systems.

Works and Publications

• Pre-threshold fractional susceptibility function: holomorphy and response formula. Preprint.
• Quenched linear response for expanding on average cocycles. Joint with D. Dragicevic and P. Giulietti. Submitted.
• A vector-valued almost sure invariance principle for random expanding on average cocycles. Joint with D. Dragicevic and Y. Hafouta. Submitted.
• Quenched limit theorems for expanding on average cocycles. Joint with D. Dragicevic. Submitted.
• Pre-threshold fractional susceptibility functions at Misiurewicz parameters. Nonlinearity 34 7174 (2021).
• Statistical stability and linear response for random hyperbolic dynamics. Joint with D. Dragicevic. Ergodic Theory and Dynamical Systems, 1-30 (2021).
• Regularity of characteristic exponents and linear response for transfer operator cocycles. Joint with H.H Rugh. Communications in Mathematical Physics 383(2), 1243-1289 (2021).
• Quadratic response of random and deterministic dynamical systems. Joint with S. Galatolo. Chaos: An Interdisciplinary Journal of Nonlinear Science 30 (2), 023113 (2020).
• Arnold maps with noise: Differentiability and non-monotonicity of the rotation number. Joint with A. DiGarbo, S. Galatolo, M. Ghil and L. Marangio. Journal of Statistical Physics 179, 1594–1624 (2020).
• Regularity of the spectrum for expanding maps. Preprint.
• A regularity result for fixed points, with applications to linear response. Nonlinearity 31 1417 (2018).
• My thesis manuscript, defended September 27th, 2018 at Orsay.

Contact: last name "at" lpsm "dot" paris
Office 129, Corridor 16-26, Sorbonne Université, 4 place Jussieu, 75005 Paris France.