335,331 research outputs found
The modal logic of set-theoretic potentialism and the potentialist maximality principles
We analyze the precise modal commitments of several natural varieties of
set-theoretic potentialism, using tools we develop for a general
model-theoretic account of potentialism, building on those of Hamkins, Leibman
and L\"owe, including the use of buttons, switches, dials and ratchets. Among
the potentialist conceptions we consider are: rank potentialism (true in all
larger ); Grothendieck-Zermelo potentialism (true in all larger
for inaccessible cardinals ); transitive-set potentialism
(true in all larger transitive sets); forcing potentialism (true in all forcing
extensions); countable-transitive-model potentialism (true in all larger
countable transitive models of ZFC); countable-model potentialism (true in all
larger countable models of ZFC); and others. In each case, we identify lower
bounds for the modal validities, which are generally either S4.2 or S4.3, and
an upper bound of S5, proving in each case that these bounds are optimal. The
validity of S5 in a world is a potentialist maximality principle, an
interesting set-theoretic principle of its own. The results can be viewed as
providing an analysis of the modal commitments of the various set-theoretic
multiverse conceptions corresponding to each potentialist account.Comment: 36 pages. Commentary can be made about this article at
http://jdh.hamkins.org/set-theoretic-potentialism. Minor revisions in v2;
further minor revisions in v
Automatic generation of hardware/software interfaces
Enabling new applications for mobile devices often requires the use of specialized hardware to reduce power consumption. Because of time-to-market pressure, current design methodologies for embedded applications require an early partitioning of the design, allowing the hardware and software to be developed simultaneously, each adhering to a rigid interface contract. This approach is problematic for two reasons: (1) a detailed hardware-software interface is difficult to specify until one is deep into the design process, and (2) it prevents the later migration of functionality across the interface motivated by efficiency concerns or the addition of features. We address this problem using the Bluespec Codesign Language~(BCL) which permits the designer to specify the hardware-software partition in the source code, allowing the compiler to synthesize efficient software and hardware along with transactors for communication between the partitions. The movement of functionality across the hardware-software boundary is accomplished by simply specifying a new partitioning, and since the compiler automatically generates the desired interface specifications, it eliminates yet another error-prone design task. In this paper we present BCL, an extension of a commercially available hardware design language (Bluespec SystemVerilog), a new software compiling scheme, and preliminary results generated using our compiler for various hardware-software decompositions of an Ogg Vorbis audio decoder, and a ray-tracing application.National Science Foundation (U.S.) (NSF (#CCF-0541164))National Research Foundation of Korea (grant from the Korean Government (MEST) (#R33-10095)
Linear superposition as a core theorem of quantum empiricism
Clarifying the nature of the quantum state is at the root of
the problems with insight into (counterintuitive) quantum postulates. We
provide a direct-and math-axiom free-empirical derivation of this object as an
element of a vector space. Establishing the linearity of this structure-quantum
superposition-is based on a set-theoretic creation of ensemble formations and
invokes the following three principia: quantum statics,
doctrine of a number in the physical theory, and
mathematization of matching the two observations with each
other; quantum invariance.
All of the constructs rest upon a formalization of the minimal experimental
entity: observed micro-event, detector click. This is sufficient for producing
the -numbers, axioms of linear vector space (superposition
principle), statistical mixtures of states, eigenstates and their spectra, and
non-commutativity of observables. No use is required of the concept of time. As
a result, the foundations of theory are liberated to a significant extent from
the issues associated with physical interpretations, philosophical exegeses,
and mathematical reconstruction of the entire quantum edifice.Comment: No figures. 64 pages; 68 pages(+4), overall substantial improvements;
70 pages(+2), further improvement
On the Pursuit of Static and Coherent Weaving
Aspect-oriented programming (AOP) has been shown to be a useful
model for software development. Special care must be taken
when we try to adapt AOP to strongly typed functional languages
which come with features like type inference mechanism, polymorphic
types, higher-order functions and type-scoped pointcuts.
Specifically, it is highly desirable that weaving of aspect-oriented
functional programs can be performed statically and coherently. In
[13], we showed a type-directed weaver which resolves all advice
chainings coherently at static time. The novelty of this paper lies in
the extended framework which supports static and coherent weaving
in the presence of polymorphic recursive functions, advising
advice bodies and higher-order advices
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