3,982 research outputs found
An Introduction to Quantum Complexity Theory
We give a basic overview of computational complexity, query complexity, and
communication complexity, with quantum information incorporated into each of
these scenarios. The aim is to provide simple but clear definitions, and to
highlight the interplay between the three scenarios and currently-known quantum
algorithms.Comment: 28 pages, LaTeX, 11 figures within the text, to appear in "Collected
Papers on Quantum Computation and Quantum Information Theory", edited by C.
Macchiavello, G.M. Palma, and A. Zeilinger (World Scientific
Does Suppositional Reasoning Solve the Bootstrapping Problem?
In a 2002 article Stewart Cohen advances the “bootstrapping problem” for what he calls “basic justification theories,” and in a 2010 followup he offers a solution to the problem, exploiting the idea that suppositional reasoning may be used with defeasible as well as with deductive inference rules. To curtail the form of bootstrapping permitted by basic justification theories, Cohen insists that subjects must know their perceptual faculties are reliable before perception can give them knowledge. But how is such knowledge of reliability to be acquired if not through perception itself? Cohen proposes that such knowledge may be acquired a priori through suppositional reasoning. I argue that his strategy runs afoul of a plausible view about how epistemic principles function; in brief, I argue that one must actually satisfy the antecedent of an epistemic principle, not merely suppose that one does, to acquire any justification by its means – even justification for a merely conditional proposition
Pathways to social evolution: reciprocity, relatedness, and synergy
Many organisms live in populations structured by space and by class, exhibit
plastic responses to their social partners, and are subject to non-additive
ecological and fitness effects. Social evolution theory has long recognized
that all of these factors can lead to different selection pressures but has
only recently attempted to synthesize how these factors interact. Using models
for both discrete and continuous phenotypes, we show that analyzing these
factors in a consistent framework reveals that they interact with one another
in ways previously overlooked. Specifically, behavioral responses
(reciprocity), genetic relatedness, and synergy interact in non-trivial ways
that cannot be easily captured by simple summary indices of assortment. We
demonstrate the importance of these interactions by showing how they have been
neglected in previous synthetic models of social behavior both within and
between species. These interactions also affect the level of behavioral
responses that can evolve in the long run; proximate biological mechanisms are
evolutionarily stable when they generate enough responsiveness relative to the
level of responsiveness that exactly balances the ecological costs and
benefits. Given the richness of social behavior across taxa, these interactions
should be a boon for empirical research as they are likely crucial for
describing the complex relationship linking ecology, demography, and social
behavior.Comment: 4 figure
Entanglement-Resistant Two-Prover Interactive Proof Systems and Non-Adaptive Private Information Retrieval Systems
We show that, for any language in NP, there is an entanglement-resistant
constant-bit two-prover interactive proof system with a constant completeness
vs. soundness gap. The previously proposed classical two-prover constant-bit
interactive proof systems are known not to be entanglement-resistant. This is
currently the strongest expressive power of any known constant-bit answer
multi-prover interactive proof system that achieves a constant gap. Our result
is based on an "oracularizing" property of certain private information
retrieval systems, which may be of independent interest.Comment: 8 page
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