We consider the inclusion and equivalence problem for unambiguous Büchi automata. We show that for a strong version of unambiguity introduced by Carton and Michel these two problems are solvable in polynomial time. We generalize this to Büchi automata with a fixed finite degree of ambiguity in the strong sense. We also discuss the problems that arise when considering the decision problems for t...

We generalize the concept of a strong inclusion on a biframe [Sch93] to that of a proximity on a biframe, which is related to the concept of a strong bi-inclusion on a frame introduced in [PP12b]. We also generalize the concept of a bi-compactification of a biframe [Sch93] to that of a compactification of a biframe, and prove that the poset of compactifications of a biframe L is isomorphic to t...

Let p be a prime k|p−1, t = (p−1)/k and γ(k, p) be the minimal value of s such that every number is a sum of s k-th powers (mod p). We prove Heilbronn’s conjecture that γ(k, p) k1/2 for t > 2. More generally we show that for any positive integer q, γ(k, p) ≤ C(q)k1/q for φ(t) ≥ q. A comparable lower bound is also given. We also establish exact values for γ(k, p) when φ(t) = 2. For instance, whe...

Although the basic building blocks for working with strong encryption have become fairly widespread in the last few years, experience has shown that implementers frequently misuse them in a manner that voids their security properties. At least some of the blame lies with the tools themselves, which often make it unnecessarily easy to get things wrong. Just as no chainsaw manufacturer would thin...

ABSTRACT In this paper, we investigate the limitations of capacity-based random code constructions for the wiretap channel, i.e., constructions that associate to each confidential message a subcode whose rate approaches the capacity of the eavesdropper’s channel. Generalizing a previous result for binary symmetric channels, we show that random capacity-based codes do not achieve the strong secr...

We prove a version of Hrushovski's 1989 results on almost orthogonal regular types in the context of simple and superstable nitary abstract elementary classes: from a certain expression of `non-orthogonality' we can conclude the existence of a group acting on the geometry obtained on the set of realizations of a regular Lascar strong type, and if we rule out the presence of a non-classical grou...

We present recent and new results for observables related to heavy quarks from a strong-coupling energy loss model that includes fluctuations in the energy loss. We find that the inclusion of these next-to-leading order fluctuations yields results consistent with all measured data. Correlation measurements and bottom decays to electrons are potential future measurements that can distinguish bet...