We show that RL ⊆ L/O(n), i.e., any language computable in randomized logarithmic space can be computed in deterministic logarithmic space with a linear amount of non-uniform advice. To prove our result we use an ultra-low space walk on the Gabber-Galil expander graph due to Gutfreund and Viola. ∗Work done while at TTI-Chicago.

Ecohydrology in Mediterranean areas: a numerical model to describe growing seasons out of phase with precipitations D. Pumo, F. Viola, and L. V. Noto Dipartimento di Ingegneria Idraulica ed Applicazioni Ambientali, University of Palermo, Viale delle Scienze, 90128 – Palermo, Italy Received: 3 August 2007 – Accepted: 20 August 2007 – Published: 4 September 2007 Correspondence to: D. Pumo (pumo@i...