2,615 research outputs found
Programming with Quantum Communication
This work develops a formal framework for specifying, implementing, and
analysing quantum communication protocols. We provide tools for developing
simple proofs and analysing programs which involve communication, both via
quantum channels and exhibiting the LOCC (local operations, classical
communication) paradigm
Programming Telepathy: Implementing Quantum Non-Locality Games
Quantum pseudo-telepathy is an intriguing phenomenon which results from the
application of quantum information theory to communication complexity. To
demonstrate this phenomenon researchers in the field of quantum communication
complexity devised a number of quantum non-locality games. The setting of these
games is as follows: the players are separated so that no communication between
them is possible and are given a certain computational task. When the players
have access to a quantum resource called entanglement, they can accomplish the
task: something that is impossible in a classical setting. To an observer who
is unfamiliar with the laws of quantum mechanics it seems that the players
employ some sort of telepathy; that is, they somehow exchange information
without sharing a communication channel. This paper provides a formal framework
for specifying, implementing, and analysing quantum non-locality games
12th International Workshop on Termination (WST 2012) : WST 2012, February 19–23, 2012, Obergurgl, Austria / ed. by Georg Moser
This volume contains the proceedings of the 12th International Workshop on Termination (WST 2012), to be held February 19–23, 2012 in Obergurgl, Austria. The goal of the Workshop on Termination is to be a venue for presentation and discussion of all topics in and around termination. In this way, the workshop tries to bridge the gaps between different communities interested and active in research in and around termination. The 12th International Workshop on Termination in Obergurgl continues the successful workshops held in St. Andrews (1993), La Bresse (1995), Ede (1997), Dagstuhl (1999), Utrecht (2001), Valencia (2003), Aachen (2004), Seattle (2006), Paris (2007), Leipzig (2009), and Edinburgh (2010). The 12th International Workshop on Termination did welcome contributions on all aspects of termination and complexity analysis. Contributions from the imperative, constraint, functional, and logic programming communities, and papers investigating applications of complexity or termination (for example in program transformation or theorem proving) were particularly welcome. We did receive 18 submissions which all were accepted. Each paper was assigned two reviewers. In addition to these 18 contributed talks, WST 2012, hosts three invited talks by Alexander Krauss, Martin Hofmann, and Fausto Spoto
Polynomial Path Orders: A Maximal Model
This paper is concerned with the automated complexity analysis of term
rewrite systems (TRSs for short) and the ramification of these in implicit
computational complexity theory (ICC for short). We introduce a novel path
order with multiset status, the polynomial path order POP*. Essentially relying
on the principle of predicative recursion as proposed by Bellantoni and Cook,
its distinct feature is the tight control of resources on compatible TRSs: The
(innermost) runtime complexity of compatible TRSs is polynomially bounded. We
have implemented the technique, as underpinned by our experimental evidence our
approach to the automated runtime complexity analysis is not only feasible, but
compared to existing methods incredibly fast. As an application in the context
of ICC we provide an order-theoretic characterisation of the polytime
computable functions. To be precise, the polytime computable functions are
exactly the functions computable by an orthogonal constructor TRS compatible
with POP*
On the strength of proof-irrelevant type theories
We present a type theory with some proof-irrelevance built into the
conversion rule. We argue that this feature is useful when type theory is used
as the logical formalism underlying a theorem prover. We also show a close
relation with the subset types of the theory of PVS. We show that in these
theories, because of the additional extentionality, the axiom of choice implies
the decidability of equality, that is, almost classical logic. Finally we
describe a simple set-theoretic semantics.Comment: 20 pages, Logical Methods in Computer Science, Long version of IJCAR
2006 pape
Automating Fine Concurrency Control in Object-Oriented Databases
Several propositions were done to provide adapted concurrency control to
object-oriented databases. However, most of these proposals miss the fact that
considering solely read and write access modes on instances may lead to less
parallelism than in relational databases! This paper cope with that issue, and
advantages are numerous: (1) commutativity of methods is determined a priori
and automatically by the compiler, without measurable overhead, (2) run-time
checking of commutativity is as efficient as for compatibility, (3) inverse
operations need not be specified for recovery, (4) this scheme does not
preclude more sophisticated approaches, and, last but not least, (5) relational
and object-oriented concurrency control schemes with read and write access
modes are subsumed under this proposition
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