852 research outputs found
On the mathematical synthesis of equational logics
We provide a mathematical theory and methodology for synthesising equational
logics from algebraic metatheories. We illustrate our methodology by means of
two applications: a rational reconstruction of Birkhoff's Equational Logic and
a new equational logic for reasoning about algebraic structure with
name-binding operators.Comment: Final version for publication in Logical Methods in Computer Scienc
Hipster: Integrating Theory Exploration in a Proof Assistant
This paper describes Hipster, a system integrating theory exploration with
the proof assistant Isabelle/HOL. Theory exploration is a technique for
automatically discovering new interesting lemmas in a given theory development.
Hipster can be used in two main modes. The first is exploratory mode, used for
automatically generating basic lemmas about a given set of datatypes and
functions in a new theory development. The second is proof mode, used in a
particular proof attempt, trying to discover the missing lemmas which would
allow the current goal to be proved. Hipster's proof mode complements and
boosts existing proof automation techniques that rely on automatically
selecting existing lemmas, by inventing new lemmas that need induction to be
proved. We show example uses of both modes
Architecture Diagrams: A Graphical Language for Architecture Style Specification
Architecture styles characterise families of architectures sharing common
characteristics. We have recently proposed configuration logics for
architecture style specification. In this paper, we study a graphical notation
to enhance readability and easiness of expression. We study simple architecture
diagrams and a more expressive extension, interval architecture diagrams. For
each type of diagrams, we present its semantics, a set of necessary and
sufficient consistency conditions and a method that allows to characterise
compositionally the specified architectures. We provide several examples
illustrating the application of the results. We also present a polynomial-time
algorithm for checking that a given architecture conforms to the architecture
style specified by a diagram.Comment: In Proceedings ICE 2016, arXiv:1608.0313
Modeling Adversaries in a Logic for Security Protocol Analysis
Logics for security protocol analysis require the formalization of an
adversary model that specifies the capabilities of adversaries. A common model
is the Dolev-Yao model, which considers only adversaries that can compose and
replay messages, and decipher them with known keys. The Dolev-Yao model is a
useful abstraction, but it suffers from some drawbacks: it cannot handle the
adversary knowing protocol-specific information, and it cannot handle
probabilistic notions, such as the adversary attempting to guess the keys. We
show how we can analyze security protocols under different adversary models by
using a logic with a notion of algorithmic knowledge. Roughly speaking,
adversaries are assumed to use algorithms to compute their knowledge; adversary
capabilities are captured by suitable restrictions on the algorithms used. We
show how we can model the standard Dolev-Yao adversary in this setting, and how
we can capture more general capabilities including protocol-specific knowledge
and guesses.Comment: 23 pages. A preliminary version appeared in the proceedings of
FaSec'0
Strategic Issues, Problems and Challenges in Inductive Theorem Proving
Abstract(Automated) Inductive Theorem Proving (ITP) is a challenging field in automated reasoning and theorem proving. Typically, (Automated) Theorem Proving (TP) refers to methods, techniques and tools for automatically proving general (most often first-order) theorems. Nowadays, the field of TP has reached a certain degree of maturity and powerful TP systems are widely available and used. The situation with ITP is strikingly different, in the sense that proving inductive theorems in an essentially automatic way still is a very challenging task, even for the most advanced existing ITP systems. Both in general TP and in ITP, strategies for guiding the proof search process are of fundamental importance, in automated as well as in interactive or mixed settings. In the paper we will analyze and discuss the most important strategic and proof search issues in ITP, compare ITP with TP, and argue why ITP is in a sense much more challenging. More generally, we will systematically isolate, investigate and classify the main problems and challenges in ITP w.r.t. automation, on different levels and from different points of views. Finally, based on this analysis we will present some theses about the state of the art in the field, possible criteria for what could be considered as substantial progress, and promising lines of research for the future, towards (more) automated ITP
Process Algebras
Process Algebras are mathematically rigorous languages with well defined semantics that permit describing and verifying properties of concurrent communicating systems.
They can be seen as models of processes, regarded as agents that act and interact continuously with other similar agents and with their common environment. The agents may be real-world objects (even people), or they may be artifacts, embodied perhaps in computer hardware or software systems.
Many different approaches (operational, denotational, algebraic) are taken for describing the meaning of processes. However, the operational approach is the reference one. By relying on the so called Structural Operational Semantics (SOS), labelled transition systems are built and composed by using the different operators of the many different process algebras. Behavioral equivalences are used to abstract from unwanted details and identify those systems that react similarly to external
experiments
Tarski's influence on computer science
The influence of Alfred Tarski on computer science was indirect but
significant in a number of directions and was in certain respects fundamental.
Here surveyed is the work of Tarski on the decision procedure for algebra and
geometry, the method of elimination of quantifiers, the semantics of formal
languages, modeltheoretic preservation theorems, and algebraic logic; various
connections of each with computer science are taken up
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