35 research outputs found
Bound non-locality and activation
We investigate non-locality distillation using measures of non-locality based
on the Elitzur-Popescu-Rohrlich decomposition. For a certain number of copies
of a given non-local correlation, we define two quantities of interest: (i) the
non-local cost, and (ii) the distillable non-locality. We find that there exist
correlations whose distillable non-locality is strictly smaller than their
non-local cost. Thus non-locality displays a form of irreversibility which we
term bound non-locality. Finally we show that non-local distillability can be
activated.Comment: 4 pages, 1 figur
Bell inequalities from multilinear contractions
We provide a framework for Bell inequalities which is based on multilinear
contractions. The derivation of the inequalities allows for an intuitive
geometric depiction and their violation within quantum mechanics can be seen as
a direct consequence of non-vanishing commutators. The approach is motivated by
generalizing recent work on non-linear inequalities which was based on the
moduli of complex numbers, quaternions and octonions. We extend results on
Peres conjecture about the validity of Bell inequalities for quantum states
with positive partial transposes. Moreover, we show the possibility of
obtaining unbounded quantum violations albeit we also prove that quantum
mechanics can only violate the derived inequalities if three or more parties
are involved.Comment: Published versio
Analyzing the Spread of Chagas Disease with Mobile Phone Data
We use mobile phone records for the analysis of mobility patterns and the
detection of possible risk zones of Chagas disease in two Latin American
countries. We show that geolocalized call records are rich in social and
individual information, which can be used to infer whether an individual has
lived in an endemic area. We present two case studies, in Argentina and in
Mexico, using data provided by mobile phone companies from each country. The
risk maps that we generate can be used by health campaign managers to target
specific areas and allocate resources more effectively.Comment: 6 pages, 6 figure
Scalability of GHZ and random-state entanglement in the presence of decoherence
We derive analytical upper bounds for the entanglement of generalized
Greenberger-Horne-Zeilinger states coupled to locally depolarizing and
dephasing environments, and for local thermal baths of arbitrary temperature.
These bounds apply for any convex quantifier of entanglement, and exponential
entanglement decay with the number of constituent particles is found. The
bounds are tight for depolarizing and dephasing channels. We also show that
randomly generated initial states tend to violate these bounds, and that this
discrepancy grows with the number of particles.Comment: 9 pages, 3 figure
Uncovering the Spread of an Infectious Disease with Mobile Phone Data
We use mobile phone records for the analysis of mobility patterns and the detection of possible risk zones of Chagas disease in two Latin American countries. We show that geolocalized call records are rich in social and individual information, which can be used to infer whether an individual has lived in an endemic area. We present two case studies, in Argentina and in Mexico, using data provided by mobile phone companies from each country. The risk maps that we generate can be used by health campaign managers to target specific areas and allocate resources more effectively. Finally, we show the value of mobile phone records to predict long-term migrations, which play a crucial role in the spread of Chagas disease.Sociedad Argentina de Informática e Investigación Operativa (SADIO
Uncovering the Spread of an Infectious Disease with Mobile Phone Data
We use mobile phone records for the analysis of mobility patterns and the detection of possible risk zones of Chagas disease in two Latin American countries. We show that geolocalized call records are rich in social and individual information, which can be used to infer whether an individual has lived in an endemic area. We present two case studies, in Argentina and in Mexico, using data provided by mobile phone companies from each country. The risk maps that we generate can be used by health campaign managers to target specific areas and allocate resources more effectively. Finally, we show the value of mobile phone records to predict long-term migrations, which play a crucial role in the spread of Chagas disease.Sociedad Argentina de Informática e Investigación Operativa (SADIO
Factoring the brain signatures of anesthesia concentration and level of arousal across individuals.
Combining resting-state functional magnetic resonance imaging (fMRI) connectivity and behavioral analysis during sedation, we factored out general effects of the anesthetic drug propofol and a specific index of conscious report, participants' level of responsiveness. The factorial analysis shows that increasing concentration of propofol in blood specifically decreases the connectivity strength of fronto-parietal cortical loops. In contrast, loss of responsiveness is indexed by a functional disconnection between the thalamus and the frontal cortex, balanced by an increase in connectivity strength of the thalamus to the occipital and temporal regions of the cortex