2,166 research outputs found
Distilling Non-Locality
Two parts of an entangled quantum state can have a correlation in their joint
behavior under measurements that is unexplainable by shared classical
information. Such correlations are called non-local and have proven to be an
interesting resource for information processing. Since non-local correlations
are more useful if they are stronger, it is natural to ask whether weak
non-locality can be amplified. We give an affirmative answer by presenting the
first protocol for distilling non-locality in the framework of generalized
non-signaling theories. Our protocol works for both quantum and non-quantum
correlations. This shows that in many contexts, the extent to which a single
instance of a correlation can violate a CHSH inequality is not a good measure
for the usefulness of non-locality. A more meaningful measure follows from our
results.Comment: Revised abstract, introduction and conclusion. Accepted by PR
Sensors for detecting analytes in fluids
Chemical sensors for detecting analytes in fluids comprise first and second conductive elements (e.g., electrical leads) electrically coupled to and separated by a chemically sensitive resistor which provides an electrical path between the conductive elements. The resistor comprises a plurality of alternating nonconductive regions (comprising a nonconductive organic polymer) and conductive regions (comprising a conductive material) transverse to the electrical path. The resistor provides a difference in resistance between the conductive elements when contacted with a fluid comprising a chemical analyte at a first concentration, than when contacted with a fluid comprising the chemical analyte at a second different concentration. Arrays of such sensors are constructed with at least two sensors having different chemically sensitive resistors providing dissimilar such differences in resistance. Variability in chemical sensitivity from sensor to sensor is provided by qualitatively or quantitatively varying the composition of the conductive and/or nonconductive regions. An electronic nose for detecting an analyte in a fluid may be constructed by using such arrays in conjunction with an electrical measuring device electrically connected to the conductive elements of each sensor
Sensors for detecting analytes in fluids
Chemical sensors for detecting analytes in fluids comprise first and second conductive elements (e.g., electrical leads) electrically coupled to and separated by a chemically sensitive resistor which provides an electrical path between the conductive elements. The resistor comprises a plurality of alternating nonconductive regions (comprising a nonconductive organic polymer) and conductive regions (comprising a conductive material) transverse to the electrical path. The resistor provides a difference in resistance between the conductive elements when contacted with a fluid comprising a chemical analyte at a first concentration, than when contacted with a fluid comprising the chemical analyte at a second different concentration. Arrays of such sensors are constructed with at least two sensors having different chemically sensitive resistors providing dissimilar such differences in resistance. Variability in chemical sensitivity from sensor to sensor is provided by qualitatively or quantitatively varying the composition of the conductive and/or nonconductive regions. An electronic nose for detecting an analyte in a fluid may be constructed by using such arrays in conjunction with an electrical measuring device electrically connected to the conductive elements of each sensor
Higher Geometric Structures on Manifolds and the Gauge Theory of Deligne Cohomology
We study smooth higher symmetry groups and moduli -stacks of generic
higher geometric structures on manifolds. Symmetries are automorphisms which
cover non-trivial diffeomorphisms of the base manifold. We construct the smooth
higher symmetry group of any geometric structure on and show that this
completely classifies, via a universal property, equivariant structures on the
higher geometry. We construct moduli stacks of higher geometric data as
-categorical quotients by the action of the higher symmetries, extract
information about the homotopy types of these moduli -stacks, and prove
a helpful sufficient criterion for when two such higher moduli stacks are
equivalent.
In the second part of the paper we study higher -connections.
First, we observe that higher connections come organised into higher groupoids,
which further carry affine actions by Baez-Crans-type higher vector spaces. We
compute a presentation of the higher gauge actions for -gerbes with
-connection, comment on the relation to higher-form symmetries, and present
a new String group model. We construct smooth moduli -stacks of higher
Maxwell and Einstein-Maxwell solutions, correcting previous such considerations
in the literature, and compute the homotopy groups of several moduli
-stacks of higher - connections. Finally, we show that a
discrepancy between two approaches to the differential geometry of NSNS
supergravity (via generalised and higher geometry, respectively) vanishes at
the level of moduli -stacks of NSNS supergravity solutions.Comment: 102 pages; comments welcom
Temperature induced phase averaging in one-dimensional mesoscopic systems
We analyse phase averaging in one-dimensional interacting mesoscopic systems
with several barriers and show that for incommensurate positions an independent
average over several phases can be induced by finite temperature. For three
strong barriers with conductances G_i and mutual distances larger than the
thermal length, we obtain G ~ sqrt{G_1 G_2 G_3} for the total conductance G.
For an interacting wire, this implies power laws in G(T) with novel exponents,
which we propose as an experimental fingerprint to distinguish temperature
induced phase averaging from dephasing.Comment: 6 pages, 5 figures; added one figure; slightly extende
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