In this work, we improve on existing results on the relationship between proof systems obtained from conflict-driven clause-learning SAT solvers and general resolution. Previous contributions such as those by Beame et al (2004), Hertel et al (2008), and Buss et al (2008) demonstrated that variations on conflict-driven clause-learning SAT solvers corresponded to proof systems as powerful as gene...

This work describes the design and implementation of an auction system using secure multiparty computation techniques. Our aim is to produce a system that is practical under actual field constraints on computation, memory, and communication. The underlying protocol is privacy-preserving, that is, the winning bid is determined without information about the losing bids leaking to either the aucti...

Proof complexity is a research area that studies the concept of complexity from the point of view of logic. In proof complexity, an important question is: “how difficult is it to prove a theorem?” There are various ways that one can measure the complexity of a theorem. We can ask what is the length of the shortest proof of a theorem in a given formal system (size of the proofs) or how strong a ...

In this paper, we introduce P-signatures. A P-signature scheme consists of a signature scheme, a commitment scheme, and (1) an interactive protocol for obtaining a signature on a committed value; (2) a non-interactive proof system for proving that the contents of a commitment has been signed; (3) a non-interactive proof system for proving that a pair of commitments are commitments to the same v...

We describe an extension of the Pvs system that provides a reasonably eecient and practical notion of reeection and thus allows for soundly adding formalized and veriied new proof procedures. These proof procedures work on representations of a part of the underlying logic and their correctness is expressed at the object level using a computational reeection function. The implementation of the P...

We present a simple and practical protocol for the solution of a secure multiparty communication task, the secret sharing, and its proof-of-principle experimental realization. In this protocol, a secret is split among several parties in a way that its reconstruction requires the collaboration of the participating parties. In our scheme the parties solve the problem by sequential transformations...

We describe an initial version of a system for mechanically checking the correctness proof of a concurrent system. Input to the system consists of the correctness properties, expressed in TLA (the temporal logic of actions), and their proofs, written in a humanly readable, hierarchically structured form. The system uses a mechanical verifier to check each step of the proof, translating the step...

Proof assistants based on type theories, such as Coq and Lego, allow users to omit subterms on input that can be inferred automatically. While those mechanisms are well known, ad-hoc algorithms are used to suppress subterms on output. As a result, terms might be printed identically although they differ in hidden parts. Such ambiguous representations may confuse users. Additionally, terms might ...

Lemma speculation has long been considered a promising technique to automate the discovery of missing lemmas for inductive proofs. This technique involves speculating a schematic lemma that becomes incrementally instantiated by unification as the proof continues. This synthesis process is known as middle-out reasoning. We have extended lemma speculation, and more generally middle-out reasoning,...

Several proof formats have been used to verify refutations produced by satisfiability (SAT) solvers. Existing formats are either costly to check or hard to implement. This paper presents a practical approach that facilitates checking of unsatisfiability results in a time similar to proof discovery by embedding clause deletion information into clausal proofs. By exploiting this information, the ...