Results for "Stephanie L. Olson"

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Earth: Atmospheric Evolution of a Habitable PlanetMar 15 2018Our present-day atmosphere is often used as an analog for potentially habitable exoplanets, but Earth's atmosphere has changed dramatically throughout its 4.5 billion year history. For example, molecular oxygen is abundant in the atmosphere today but ... More
A limited habitable zone for complex lifeFeb 13 2019The habitable zone (HZ) is defined as the range of distances from a host star within which liquid water, a key requirement for life, may exist at a planet's surface. Substantially more CO2 than present in Earth's modern atmosphere is required to maintain ... More
Atmospheric Seasonality as an Exoplanet BiosignatureJun 12 2018Current investigations of exoplanet biosignatures have focused on static evidence of life, such as the presence of biogenic gases like O2 or CH4. However, the expected diversity of terrestrial planet atmospheres and the likelihood of both false positives ... More
Rethinking CO Antibiosignatures in the Search for Life Beyond the Solar SystemMar 18 2019Some atmospheric gases have been proposed as counter indicators to the presence of life on an exoplanet if remotely detectable at sufficient abundance (i.e., antibiosignatures), informing the search for biosignatures and potentially fingerprinting uninhabited ... More
The Importance of UV Capabilities for Identifying Inhabited Exoplanets with Next Generation Space TelescopesJan 09 2018The strongest remotely detectable signature of life on our planet today is the photosynthetically produced oxygen (O2) in our atmosphere. However, recent studies of Earth's geochemical proxy record suggest that for all but the last ~500 million years, ... More
Disequilibrium biosignatures over Earth history and implications for detecting exoplanet lifeJan 24 2018Chemical disequilibrium in planetary atmospheres has been proposed as a generalized method for detecting life on exoplanets through remote spectroscopy. Among solar system planets with substantial atmospheres, the modern Earth has the largest thermodynamic ... More
The remote detectability of Earth's biosphere through time and the importance of UV capability for characterizing habitable exoplanetsMar 13 2019Thousands of planets beyond our solar system have been discovered to date, dozens of which are rocky in composition and are orbiting within the circumstellar habitable zone of their host star. The next frontier in life detection beyond our solar system ... More
Learning Unitary Operators with Help From u(n)Jul 17 2016A major challenge in the training of recurrent neural networks is the so-called vanishing or exploding gradient problem. The use of a norm-preserving transition operator can address this issue, but parametrization is challenging. In this work we focus ... More
Gas Stripping in Simulated Galaxies with a Multiphase ISMJan 14 2009Cluster galaxies moving through the intracluster medium (ICM) are expected to lose some of their interstellar medium (ISM) through ISM-ICM interactions. We perform high resolution (40 pc) three-dimensional hydrodynamical simulations of a galaxy undergoing ... More
Star Formation in Ram Pressure Stripped TailsMar 01 2012We investigate the impact of star formation and feedback on ram pressure stripping using high-resolution adaptive mesh simulations, building on a previous series of papers that systematically investigated stripping using a realistic model for the interstellar ... More
The Tail of the Stripped Gas that Cooled: HI, Halpha and X-ray Observational Signatures of Ram Pressure StrippingSep 17 2009Galaxies moving through the intracluster medium (ICM) of a cluster of galaxies can lose gas via ram pressure stripping. This stripped gas forms a tail behind the galaxy which is potentially observable. In this paper, we carry out hydrodynamical simulations ... More
Learning Unitary Operators with Help From u(n)Jul 17 2016Jan 10 2017A major challenge in the training of recurrent neural networks is the so-called vanishing or exploding gradient problem. The use of a norm-preserving transition operator can address this issue, but parametrization is challenging. In this work we focus ... More
How To Light It Up: Simulating Ram-Pressure Stripped X-ray Bright TailsMar 16 2011Some tails of ram-pressure stripped galaxies are detected in HI, some in Halpha, and some in X-ray (but never all three so far). We use numerical simulations to probe the conditions for the production of X-ray bright tails, demonstrating that the primary ... More
Lorentz and semi-Riemannian spaces with Alexandrov curvature boundsApr 15 2008A semi-Riemannian manifold is said to satisfy $R\ge K$ (or $R\le K$) if spacelike sectional curvatures are $\ge K$ and timelike ones are $\le K$ (or the reverse). Such spaces are abundant, as warped product constructions show; they include, in particular, ... More
Warped products admitting a curvature boundSep 01 2015Sep 12 2016This paper completes a fundamental construction in Alexandrov geometry. Previously we gave a new construction of metric spaces with curvature bounds either above or below, namely warped products with intrinsic metric space base and fiber, and with possibly ... More
Exoplanet Biosignatures: A Review of Remotely Detectable Signs of LifeMay 16 2017Jun 25 2018In the coming years and decades, advanced space- and ground-based observatories will allow an unprecedented opportunity to probe the atmospheres and surfaces of potentially habitable exoplanets for signatures of life. Life on Earth, through its gaseous ... More
A Generative Model of Words and Relationships from Multiple SourcesOct 01 2015Dec 03 2015Neural language models are a powerful tool to embed words into semantic vector spaces. However, learning such models generally relies on the availability of abundant and diverse training examples. In highly specialised domains this requirement may not ... More
Real-valued (Medical) Time Series Generation with Recurrent Conditional GANsJun 08 2017Dec 04 2017Generative Adversarial Networks (GANs) have shown remarkable success as a framework for training models to produce realistic-looking data. In this work, we propose a Recurrent GAN (RGAN) and Recurrent Conditional GAN (RCGAN) to produce realistic real-valued ... More
Knowledge Transfer with Medical Language EmbeddingsFeb 10 2016Identifying relationships between concepts is a key aspect of scientific knowledge synthesis. Finding these links often requires a researcher to laboriously search through scien- tific papers and databases, as the size of these resources grows ever larger. ... More
New Constraints on Models for Circumgalactic Gas Inflow: How Do Galaxies Get Their Gas at Low Redshift?Jan 31 2019We constrain gas inflow speeds in several star-forming galaxies having color gradients consistent with inside-out disk growth. Our method combines new measurements of disk orientation with previously described circumgalactic absorption in background quasar ... More
How Gas Accretion Feeds Galactic DisksMar 15 2019Numerous observations indicate that galaxies need a continuous gas supply to fuel star formation and explain the star formation history. However, direct observational evidence of gas accretion remains rare. Using the EAGLE cosmological hydrodynamic simulation ... More
Effects of Load-Based Frequency Regulation on Distribution Network OperationJul 09 2018This paper examines the operation of distribution networks that have large aggregations of thermostatically controlled loads (TCLs) providing secondary frequency regulation to the bulk power system. Specifically, we assess the prevalence of distribution ... More
Neural Document Embeddings for Intensive Care Patient Mortality PredictionDec 01 2016We present an automatic mortality prediction scheme based on the unstructured textual content of clinical notes. Proposing a convolutional document embedding approach, our empirical investigation using the MIMIC-III intensive care database shows significant ... More
Simulating the Coronal Evolution of AR 11437 using SDO/HMI MagnetogramsDec 01 2017The coronal magnetic field evolution of AR 11437 is simulated by applying the magnetofrictional relaxation technique of Mackay et al. (2011). A sequence of photospheric line-of-sight magnetograms produced by SDO/HMI are used to drive the simulation and ... More
False negatives for remote life detection on ocean-bearing planets: Lessons from the early EarthFeb 03 2017Ocean-atmosphere chemistry on Earth has undergone dramatic evolutionary changes through its long history, with potentially significant ramifications for the emergence and long-term stability of atmospheric biosignatures. Though a great deal of work has ... More
Effect of FET geometry on charge ordering of transition metal oxidesNov 27 2002We examine the effect of an FET geometry on the charge ordering phase diagram of transition metal oxides using numerical simulations of a semiclassical model including long-range Coulomb fields, resulting in nanoscale pattern formation. We find that the ... More
Life Beyond the Solar System: Remotely Detectable BiosignaturesJan 20 2018For the first time in human history, we will soon be able to apply the scientific method to the question "Are We Alone?" The rapid advance of exoplanet discovery, planetary systems science, and telescope technology will soon allow scientists to search ... More
A Statistical Comparative Planetology Approach to Maximize the Scientific Return of Future Exoplanet Characterization EffortsMar 12 2019Provided that sufficient resources are deployed, we can look forward to an extraordinary future in which we will characterize potentially habitable planets. Until now, we have had to base interpretations of observations on habitability hypotheses that ... More
Pinning, Flux Diodes, and Ratchets for Vortices Interacting with Conformal Pinning ArraysFeb 11 2016A conformal pinning array can be created by conformally transforming a uniform triangular pinning lattice to produces a new structure in which the six-fold ordering of the original lattice is conserved but where there is a spatial gradient in the density ... More
Ultrafast entangling gates between nuclear spins using photo-excited triplet statesJan 23 2012The representation of information within the spins of electrons and nuclei has been powerful in the ongoing development of quantum computers. Although nuclear spins are advantageous as quantum bits (qubits) due to their long coherence lifetimes (exceeding ... More
Weierstrass points on $X_0^+(p)$ and supersingular $j$-invariantsFeb 16 2017We study the arithmetic properties of Weierstrass points on the modular curves $X_0^+(p)$ for primes $p$. In particular, we obtain a relationship between the Weierstrass points on $X_0^+(p)$ and the $j$-invariants of supersingular elliptic curves in characteristic ... More
E_n-cohomology with coefficients as functor cohomologyDec 18 2014Feb 19 2015Building on work of Livernet and Richter, we prove that E_n-homology and E_n-cohomology of a commutative algebra with coefficients in a symmetric bimodule can be interpreted as functor homology and cohomology. Furthermore we show that the associated Yoneda ... More
A Two Stage Vehicle Routing Algorithm Applied to Disaster Relief Logistics after the 2015 Nepal EarthquakeSep 01 2017After the April 2015 Nepal Earthquake, the Himalayan Disaster Relief Volunteer Group distributed supplies to affected areas. We model HDRVG's operations as a vehicle routing problem using Fisher and Jaikumar's two stage method, which allocates locations ... More
A Mordell Inequality for Lattices over Maximal OrdersOct 14 2008Jul 30 2010In this paper we prove an analogue of Mordell's inequality for lattices in finite-dimensional complex or quaternionic Hermitian space that are modules over a maximal order in an imaginary quadratic number field or a totally definite rational quaternion ... More
Quiver $\mathscr{D}$-modules and the Riemann-Hilbert correspondenceMay 19 2015May 20 2015In this paper, we show that every regular singular $\mathscr{D}$-module in $\mathbb{C}^n$ whose singular locus is a normal crossing is isomorphic to a quiver $\mathscr{D}$-module - a $\mathscr{D}$-module whose definition is based on certain representations ... More
The Journey Counts: The Importance of Including Orbits when Simulating Ram Pressure StrippingMar 19 2019We investigate the importance of varying the ram pressure to more realistically mimic the infall of a cluster satellite galaxy when comparing ram pressure stripping simulations to observations. We examine the gas disk and tail properties of stripped cluster ... More
Effective Field Theory Treatment of Monopole Production by Drell-Yan and Photon Fusion for Various SpinsMay 22 2019A resolution over the existence of magnetic charges has eluded the high energy physics community for centuries, and their search has gained momentum as recent models predict these may be observable at current colliders. They appear in field theories in ... More
Charged-Higgs effects in B --> (D) tau nu decaysOct 20 2008We update and compare the capabilities of the purely leptonic mode B --> tau nu and the semileptonic mode B --> D tau nu in the search for a charged Higgs boson.
Kaon-Scatter Introduced Backgrounds in the KOTO ExperimentOct 02 2017The KOTO experiment is a particle physics experiment located in J-PARC, Japan, aiming to explore physics beyond the Standard Model by measuring the branching ratio of the $K_L\rightarrow\pi^{0}\nu\bar{\nu}$ decay. This decay has not yet been observed. ... More
Improving Clinical Predictions through Unsupervised Time Series Representation LearningDec 02 2018In this work, we investigate unsupervised representation learning on medical time series, which bears the promise of leveraging copious amounts of existing unlabeled data in order to eventually assist clinical decision making. By evaluating on the prediction ... More
Evolution of magnetic properties in the normal spinel solid solution Mg(1-x)Cu(x)Cr2O4Oct 07 2011We examine the evolution of magnetic properties in the normal spinel oxides Mg(1-x)Cu(x)Cr2O4 using magnetization and heat capacity measurements. The end-member compounds of the solid solution series have been studied in some detail because of their very ... More
Quasars Probing Galaxies: I. Signatures of Gas Accretion at Redshift Approximately 0.2Nov 14 2016Feb 09 2017We describe the kinematics of circumgalactic gas near the galactic plane, combining new measurements of galaxy rotation curves and spectroscopy of background quasars. The sightlines pass within 19--93 kpc of the target galaxy and generally detect Mg II ... More
Physical Properties of Local Star-Forming Analogues to z~5 Lyman Break GalaxiesMar 23 2016Intense, compact, star-forming galaxies are rare in the local Universe but ubiquitous at high redshift. We interpret the 0.1-22 um spectral energy distributions (SED) of a sample of 180 galaxies at 0.05<z<0.25 selected for extremely high surface densities ... More
Regularity and Locality of Point Defects in MultilatticesAug 31 2016We formulate a model for a point defect embedded in a homogeneous multilattice crystal with an empirical interatomic potential interaction. Under a natural, phonon stability assumption we quantify the decay of the long-range elastic fields with increasing ... More
Rational Right Triangles of a Given AreaJun 19 2017Starting from any given rational-sided, right triangle, for example the $(3,4,5)$-triangle with area $6$, we use Euclidean geometry to show that there are infinitely many other rational-sided, right triangles of the same area. We show further that the ... More
Improved sphere packing lower bounds from Hurwitz latticesMay 19 2011In this paper we prove an asymptotic lower bound for the sphere packing density in dimensions divisible by four. This asymptotic lower bound improves on previous asymptotic bounds by a constant factor and improves not just lower bounds for the sphere ... More
Long-term implications of observing an expanding cosmological civilizationAug 26 2016May 20 2017Suppose that advanced civilizations, separated by a cosmological distance and time, wish to maximize their access to cosmic resources by rapidly expanding into the universe. How does the presence of one limit the expansionistic ambitions of another, and ... More
Homogeneous cosmology with aggressively expanding civilizationsNov 17 2014Oct 20 2015In the context of a homogeneous universe, we note that the appearance of aggressively expanding advanced life is geometrically similar to the process of nucleation and bubble growth in a first-order cosmological phase transition. We exploit this similarity ... More
Uncovering Obscured Active Galactic Nuclei in Homogeneously Selected Samples of Seyfert 2 GalaxiesJan 04 2011We have analyzed archival \textit{Chandra} and \textit{XMM-Newton} data for two nearly complete homogeneously selected samples of type 2 Seyfert galaxies (Sy2s). These samples were selected based on intrinsic Active Galactic Nuclei (AGN) flux proxies: ... More
Kinematics of Circumgalactic Gas: Feeding Galaxies and FeedbackJan 26 2019Apr 25 2019We present observations of 50 pairs of redshift z ~ 0.2 star-forming galaxies and background quasars. These sightlines probe the circumgalactic medium (CGM) out to half the virial radius, and we describe the circumgalactic gas kinematics relative to the ... More
Magnetic field sensors using 13-spin cat statesJul 09 2009Nov 24 2010Measurement devices could benefit from entangled correlations to yield a measurement sensitivity approaching the physical Heisenberg limit. Building upon previous magnetometric work using pseudo-entangled spin states in solution-state NMR, we present ... More
Exploring the Role of Sub-micron Sized Dust Grains in the Atmospheres of Red L0 - L6 DwarfsJun 24 2016We examine the hypothesis that the red near-infrared colors of some L dwarfs could be explained by a "dust haze" of small particles in their upper atmospheres. This dust haze would exist in conjunction with the clouds found in dwarfs with more typical ... More
Experimental n-Hexane-Air Expanding Spherical FlamesOct 23 2018The effects of initial pressure and temperature on the laminar burning speed of n-hexane-air mixtures were investigated experimentally and numerically. The spherically expanding flame technique with a nonlinear extrapolation procedure was employed to ... More
Optical measurements of strong microwave fields with Rydberg atoms in a vapor cellJan 11 2016We present a spectral analysis of Rydberg atoms in strong microwave fields using electromagnetically induced transparency (EIT) as an all-optical readout. The measured spectroscopic response enables optical, atom-based electric field measurements of high-power ... More
$^{29}$Si nuclear spins as a resource for donor spin qubits in siliconMay 08 2015Nuclear spin registers in the vicinity of electron spins in solid state systems offer a powerful resource to address the challenge of scalability in quantum architectures. We investigate here the properties of $^{29}$Si nuclear spins surrounding donor ... More
Are Starspots and Plages Co-Located on Active G and K Stars?Sep 12 2018We explore the connection between starspots and plages of three main-sequence stars by studying the chromospheric and photospheric activity over several rotation periods. We present simultaneous photometry and high-resolution ($R\sim 31,500$) spectroscopy ... More
Emergent three-dimensional sperm motility: Coupling calcium dynamics and preferred curvature in a Kirchhoff rod modelApr 12 2018Changes in calcium concentration along the sperm flagellum regulates sperm motility and hyperactivation, characterized by an increased flagellar bend amplitude and beat asymmetry, enabling the sperm to reach and penetrate the ovum (egg). The signaling ... More
Radio observations confirm young stellar populations in local analogues to $z\sim5$ Lyman break galaxiesMay 22 2017We present radio observations at 1.5 GHz of 32 local objects selected to reproduce the physical properties of $z\sim5$ star-forming galaxies. We also report non-detections of five such sources in the sub-millimetre. We find a radio-derived star formation ... More
Unsupervised Classification in Hyperspectral Imagery with Nonlocal Total Variation and Primal-Dual Hybrid Gradient AlgorithmApr 27 2016Feb 13 2017In this paper, a graph-based nonlocal total variation method (NLTV) is proposed for unsupervised classification of hyperspectral images (HSI). The variational problem is solved by the primal-dual hybrid gradient (PDHG) algorithm. By squaring the labeling ... More
An Optical and Infrared Time-Domain Study of the Supergiant Fast X-ray Transient Candidate IC 10 X-2Dec 15 2017We present an optical and infrared (IR) study of IC 10 X-2, a high-mass X-ray binary in the galaxy IC 10. Previous optical and X-ray studies suggest X-2 is a Supergiant Fast X-ray Transient: a large-amplitude (factor of $\sim$ 100), short-duration (hours ... More
Contact-less measurements of Shubnikov-de Haas oscillations in the magnetically ordered state of CeAgSb$_2$ and SmAgSb$_2$ single crystalsMay 22 2006May 24 2006Shubnikov - de Haas oscillations were measured in single crystals of highly metallic antiferromagnetic SmAgSb$_{2}$ and ferromagnetic CeAgSb$_{2}$ using a tunnel diode resonator. Resistivity oscillations as a function of applied magnetic field were observed ... More
X-ray Cluster Associated with the z=1.063 CSS Quasar 3C 186: The Jet is NOT FrustratedJun 16 2005We report the Chandra discovery of an X-ray cluster at redshift z = 1.063 associated with the Compact Steep Spectrum radio loud quasar 3C 186 (Q0740+380). Diffuse X-ray emission is detected out to ~120 kpc from the quasar and contains 741+/-40 net counts. ... More
Broadband Rydberg Atom-Based Electric-Field Probe: From Self-Calibrated Measurements to Sub-Wavelength ImagingMay 27 2014We discuss a fundamentally new approach for the measurement of electric (E) fields that will lead to the development of a broadband, direct SI-traceable, compact, self-calibrating E-field probe (sensor). This approach is based on the interaction of radio ... More
ARPES Line Shapes in FL and non-FL Quasi-Low-Dimensional Inorganic MetalsMar 22 2001Quasi-low-dimensional (quasi-low-D) inorganic materials are not only ideally suited for angle resolved photoemission spectroscopy (ARPES) but also they offer a rich ground for studying key concepts for the emerging paradigm of non-Fermi liquid (non-FL) ... More
ARPES Study of X-Point Band Overlaps in LaB$_6$ and SmB$_6$ - Contrast to SrB$_6$ and EuB$_6$Jul 10 2001In contrast to our recent finding of an X-point band gap in divalent hexaborides, we report here that angle resolved photoemission spectroscopy (ARPES) data shows that the gap is absent for trivalent LaB$_6$ and is absent or nearly so for mixed valent ... More
RG flows in d dimensions, the dilaton effective action, and the a-theoremSep 15 2012Jul 15 2013Motivated by the recent dilaton-based proof of the 4d a-theorem, we study the dilaton effective action for RG flows in d dimensions. When d is even, the action consists of a Wess-Zumino (WZ) term, whose Weyl-variation encodes the trace-anomaly, plus all ... More
A hybrid cellular automaton model of cartilage regeneration capturing the interactions between cellular dynamics and scaffold porosityAug 29 2018To accelerate the development of strategies for cartilage tissue engineering, models are necessary to study the interactions between cellular dynamics and scaffold (SC) porosity. In experiments, cells are seeded in a porous SC where over a month, the ... More
A pilot study using deep infrared imaging to constrain the star formation history of the XUV stellar populations in NGC 4625Sep 02 2014In a LCDM universe, disk galaxies' outer regions are the last to form. Characterizing their contents is critical for understanding the ongoing process of disk formation, but observing outer disk stellar populations is challenging due to their low surface ... More
Enhanced star formation in both disks and ram pressure stripped tails of GASP jellyfish galaxiesOct 11 2018Exploiting the data from the GAs Stripping Phenomena in galaxies with MUSE (GASP) program, we compare the integrated Star Formation Rate- Mass relation (SFR-M_ast) relation of 42 cluster galaxies undergoing ram pressure stripping ("stripping galaxies") ... More
The Energetics of Molecular Adaptation in Transcriptional RegulationMay 15 2019Mutation is a critical mechanism by which evolution explores the functional landscape of proteins. Despite our ability to experimentally inflict mutations at will, it remains difficult to link sequence-level perturbations to systems-level responses. Here, ... More
Hydrodynamical Adaptive Mesh Refinement Simulations of Disk GalaxiesAug 05 2008Aug 30 2008To date, fully cosmological hydrodynamic disk simulations to redshift zero have only been undertaken with particle-based codes, such as GADGET, Gasoline, or GCD+. In light of the (supposed) limitations of traditional implementations of smoothed particle ... More
Predicting evolutionary site variability from structure in viral proteins: buriedness, packing, flexibility, and designApr 29 2014Jul 21 2014Several recent works have shown that protein structure can predict site-specific evolutionary sequence variation. In particular, sites that are buried and/or have many contacts with other sites in a structure have been shown to evolve more slowly, on ... More
Sub-Wavelength Imaging and Field Mapping via EIT and Autler-Townes Splitting In Rydberg AtomsApr 01 2014We present a technique for measuring radio-frequency (RF) electric field strengths with sub-wavelength resolution. We use Rydberg states of rubidium atoms to probe the RF field. The RF field causes an energy splitting of the Rydberg states via the Autler-Townes ... More
First Data Release of the All-sky NOAO Source CatalogJan 05 2018Jul 26 2018Most of the sky has been imaged with NOAO's telescopes from both hemispheres. While the large majority of these data were obtained for PI-led projects and almost all of the images are publicly available, only a small fraction have been released to the ... More
Tuning transcriptional regulation through signaling: A predictive theory of allosteric inductionFeb 24 2017Jun 21 2017Allosteric regulation is found across all domains of life, yet we still lack simple, predictive theories that directly link the experimentally tunable parameters of a system to its input-output response. To that end, we present a general theory of allosteric ... More
Millimeter Wave Detection via Autler-Townes Splitting in Rubidium Rydberg AtomsJun 11 2014In this paper we demonstrate the detection of millimeter waves via Autler-Townes splitting in 85Rb Rydberg atoms. This method may provide an independent, atom-based, SI-traceable method for measuring mm-wave electric fields, which addresses a gap in current ... More
Device-independent two-party cryptography secure against sequential attacksJan 25 2016May 09 2016The goal of two-party cryptography is to enable two parties, Alice and Bob, to solve common tasks without the need for mutual trust. Examples of such tasks are private access to a database, and secure identification. Quantum communication enables security ... More
(Nearly) optimal P-values for all Bell inequalitiesOct 25 2015Mar 15 2016A key objective in conducting a Bell test is to quantify the statistical evidence against a local-hidden variable model (LHVM) given that we can collect only a finite number of trials in any experiment. The notion of statistical evidence is thereby formulated ... More
Computability limits non-local correlationsMay 07 2012Jan 28 2013If the no-signalling principle was the only limit to the strength of non-local correlations, we would expect that any form of no-signalling correlation can indeed be realized. That is, there exists a state and measurements that remote parties can implement ... More
Does ignorance of the whole imply ignorance of the parts? - Large violations of non-contextuality in quantum theoryNov 30 2010May 04 2011A central question in our understanding of the physical world is how our knowledge of the whole relates to our knowledge of the individual parts. One aspect of this question is the following: to what extent does ignorance about a whole preclude knowledge ... More
More non-locality with less entanglementNov 23 2010Dec 08 2010We provide an explicit example of a Bell inequality with 3 settings and 2 outcomes per site for which the largest violation is not obtained by the maximally entangled state, even if its dimension is allowed to be arbitrarily large. This complements recent ... More
Tautological pairings on moduli spaces of curvesFeb 14 2009Feb 26 2009We discuss analogs of Faber's conjecture for two nested sequences of partial compactifications of the moduli space of smooth curves. We show that their tautological rings are one-dimensional in top degree but do not satisfy Poincare duality.
Social Networks Analysis in Discovering the Narrative Structure of Literary FictionAug 21 2016In our paper we would like to make a cross-disciplinary leap and use the tools of network theory to understand and explore narrative structure in literary fiction, an approach that is still underestimated. However, the systems in fiction are sensitive ... More
Rigorous results for the distribution of money on connected graphsJan 01 2018This paper is concerned with general spatially explicit versions of three stochastic models for the dynamics of money that have been introduced and studied numerically by statistical physicists: the uniform reshuffling model, the immediate exchange model ... More
A violation of the uncertainty principle implies a violation of the second law of thermodynamicsMay 31 2012Uncertainty relations state that there exist certain incompatible measurements, to which the outcomes cannot be simultaneously predicted. While the exact incompatibility of quantum measurements dictated by such uncertainty relations can be inferred from ... More
Electric dipole moment searches: reexamination of frequency shifts for particles in trapsJan 03 2012May 02 2012In experiments searching for a nonzero electric dipole moment of trapped particles, frequency shifts correlated with an applied electric field can be interpreted as a false signal. One such effect, referred to as the geometric phase effect, is known to ... More
CurvedLand: An Applet for Illustrating Curved Geometry without EmbeddingOct 07 2010We have written a Java applet to illustrate the meaning of curved geometry. The applet provides a mapping interface similar to MapQuest or Google Maps; features include the ability to navigate through a space and place permanent point objects and/or shapes ... More
Long distance two-party quantum cryptography made simpleAug 02 2010Any two-party cryptographic primitive can be implemented using quantum communication under the assumption that it is difficult to store a large number of quantum states perfectly. However, achieving reliable quantum communication over long distances remains ... More
On the Reversal of SFR-Density Relation at z=1: Insights from SimulationsMay 05 2014Recent large surveys have found a reversal of the star formation rate (SFR)-density relation at z=1 from that at z=0 (e.g. Elbaz et al.; Cooper et al.), while the sign of the slope of the color-density relation remains unchanged (e.g. Cucciati et al.; ... More
A spectral sequence for the homology of a finite algebraic deloopingFeb 04 2013Oct 29 2015In the world of chain complexes E_n-algebras are the analogues of based n-fold loop spaces in the category of topological spaces. Fresse showed that operadic E_n-homology of an E_n-algebra computes the homology of an n-fold algebraic delooping. The aim ... More
Nanotube bundles and tube-tube orientation: A van der Waals Density Functional StudyJul 19 2012We study the binding energy, intertube distance and electronic structure of bundles consisting of single walled carbon nanotubes of the same chirality. We model various nanotube structures (chiralities) and orientations with van der Waals density functional ... More
Almost All Quantum States Have Low Entropy Rates for Any Coupling to the EnvironmentSep 03 2011Mar 23 2012The joint state of a system that is in contact with an environment is called lazy, if the entropy rate of the system under any coupling to the environment is zero. Necessary and sufficient conditions have recently been established for a state to be lazy ... More
SimulaQron - A simulator for developing quantum internet softwareDec 21 2017Jul 14 2018We introduce a simulator for a quantum internet with the specific goal to support software development. A quantum internet consists of local quantum processors, which are interconnected by quantum communication channels that enable the transmission of ... More
Finite blocklength converse bounds for quantum channelsOct 17 2012Jun 27 2014We derive upper bounds on the rate of transmission of classical information over quantum channels by block codes with a given blocklength and error probability, for both entanglement-assisted and unassisted codes, in terms of a unifying framework of quantum ... More
Achieving the physical limits of the bounded-storage modelSep 08 2010May 04 2011Secure two-party cryptography is possible if the adversary's quantum storage device suffers imperfections. For example, security can be achieved if the adversary can store strictly less then half of the qubits transmitted during the protocol. This special ... More
Entropic uncertainty relations - A surveyJul 21 2009Uncertainty relations play a central role in quantum mechanics. Entropic uncertainty relations in particular have gained significant importance within quantum information, providing the foundation for the security of many quantum cryptographic protocols. ... More
Lowering qubit requirements for quantum simulations of fermionic systemsDec 19 2017Oct 11 2018The mapping of fermionic states onto qubit states, as well as the mapping of fermionic Hamiltonian into quantum gates enables us to simulate electronic systems with a quantum computer. Benefiting the understanding of many-body systems in chemistry and ... More
Asynchronous reference frame agreement in a quantum networkMay 11 2015Mar 30 2016An efficient implementation of many multiparty protocols for quantum networks requires that all the nodes in the network share a common reference frame. Establishing such a reference frame from scratch is especially challenging in an asynchronous network ... More
Signature of Cooper Pairs in the Non-Superconducting Phases of Amorphous Superconducting Tantalum FilmsFeb 11 2015We have studied the magnetic field or disorder induced insulating and metallic phases in amorphous Ta superconducting thin films. The evolution of the nonlinear transport in the insulating phase exhibits a non-monotonic behavior as the magnetic field ... More
Chirality-Dependent Growth Rate of Carbon Nanotubes - A Theoretical StudyJul 19 2012We consider geometric constraints for the addition of carbon atoms to the rim of a growing nanotube. The growth of a tube proceeds through the conversion of dangling bonds from armchair to zigzag and vice versa. We find that the growth rate depends on ... More