4,038 research outputs found
An entropic approach to local realism and noncontextuality
For any Bell locality scenario (or Kochen-Specker noncontextuality scenario),
the joint Shannon entropies of local (or noncontextual) models define a convex
cone for which the non-trivial facets are tight entropic Bell (or
contextuality) inequalities. In this paper we explore this entropic approach
and derive tight entropic inequalities for various scenarios. One advantage of
entropic inequalities is that they easily adapt to situations like bilocality
scenarios, which have additional independence requirements that are non-linear
on the level of probabilities, but linear on the level of entropies. Another
advantage is that, despite the nonlinearity, taking detection inefficiencies
into account turns out to be very simple. When joint measurements are conducted
by a single detector only, the detector efficiency for witnessing quantum
contextuality can be arbitrarily low.Comment: 12 pages, 8 figures, minor mistakes correcte
WebProt\'eg\'e: A Cloud-Based Ontology Editor
We present WebProt\'eg\'e, a tool to develop ontologies represented in the
Web Ontology Language (OWL). WebProt\'eg\'e is a cloud-based application that
allows users to collaboratively edit OWL ontologies, and it is available for
use at https://webprotege.stanford.edu. WebProt\'ege\'e currently hosts more
than 68,000 OWL ontology projects and has over 50,000 user accounts. In this
paper, we detail the main new features of the latest version of WebProt\'eg\'e
Fractional-Spin Integrals of Motion for the Boundary Sine-Gordon Model at the Free Fermion Point
We construct integrals of motion (IM) for the sine-Gordon model with boundary
at the free Fermion point which correctly determine the boundary S matrix. The
algebra of these IM (``boundary quantum group'' at q=1) is a one-parameter
family of infinite-dimensional subalgebras of twisted affine sl(2). We also
propose the structure of the fractional-spin IM away from the free Fermion
point.Comment: 19 pages, LaTeX, no figure
The friendship paradox in scale-free networks
Our friends have more friends than we do. That is the basis of the friendship
paradox. In mathematical terms, the mean number of friends of friends is higher
than the mean number of friends. In the present study, we analyzed the
relationship between the mean degree of vertices (individuals), , and the
mean number of friends of friends, , in scale-free networks with degrees
ranging from a minimum degree (k_min) to a maximum degree (k_max). We deduced
an expression for - for scale-free networks following a power-law
distribution with a given scaling parameter (alpha). Based on this expression,
we can quantify how the degree distribution of a scale-free network affects the
mean number of friends of friends.Comment: 9 pages, 2 figure
Feasibility of loophole-free nonlocality tests with a single photon
Recently much interest has been directed towards designing setups that
achieve realistic loss thresholds for decisive tests of local realism, in
particular in the optical regime. We analyse the feasibility of such Bell tests
based on a W-state shared between multiple parties, which can be realised for
example by a single photon shared between spatial modes. We develop a general
error model to obtain thresholds on the efficiencies required to violate local
realism, and also consider two concrete optical measurement schemes.Comment: 8 pages, 5 figure
Mathematical modeling of recombinant Escherichia coli aerobic batch fermentations
In this work, three competing unstructured mathematical models for the biomass
growth by recombinant E. coli strains with different acetate inhibition kinetics terms
were evaluated for batch processes at constant temperature and pH.
The models considered the dynamics of biomass growth, acetate accumulation,
substrate consumption, Green Fluorescence Protein (GFP) production and three
metabolic pathways for E. coli. Parameter estimation and model validation was carried
out using the Systems Biology toolbox for Matlab (The Mathworks) with different initial
glucose concentrations (5g/kg to 25g/kg) in a 5dm3 bioreactor. Model discrimination was
based on the two model selection criterion (Akaike’s information criterion and
normalized quadratic difference between the simulated and experimental data
criterion). The first model described by Jerusalimsky approach is an approximation to
the non-competitive substrate inhibition. Cockshott approach describes the inhibition at
high acetate levels and Levenspiel considers the critical inhibitory acetate
concentration that limits growth. Within the studied experimental range, Jerusalimsky
model provided a good approximation between real and simulated values and should
be favored. The model describes the experimental data satisfactorily well
Model reduction based on dynamic sensitivity analysis : a systems biology case of study
Fundação para a Ciência e a Tecnologia (FCT
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