Results for "Douglas T. McClure"

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Verifying Multipartite Entangled GHZ States via Multiple Quantum CoherencesMay 14 2019The ability to generate and verify multipartite entanglement is an important benchmark for near-term quantum devices devices. We develop a scalable entanglement metric based on multiple quantum coherences, and demonstrate experimentally on a 20-qubit ... More
On the relation between Unruh and Sokolov--Ternov effectsOct 29 2006May 13 2007We show that the Sokolov--Ternov effect -- the depolarization of particles in storage rings coming from synchrotron radiation due to spin flip transitions -- is physically equivalent to the Unruh effect for circular acceleration if one uses a spin 1/2 ... More
A quantum mechanical approach to establishing the magnetic field orientation from a maser Zeeman profileApr 23 2014Recent comparisons of magnetic field directions derived from maser Zeeman splitting with those derived from continuum source rotation measures have prompted new analysis of the propagation of the Zeeman split components, and the inferred field orientation. ... More
Shot Noise in GrapheneNov 20 2007Feb 21 2008We report measurements of current noise in single- and multi-layer graphene devices. In four single-layer devices, including a p-n junction, the Fano factor remains constant to within +/-10% upon varying carrier type and density, and averages between ... More
MAGMO: Coherent magnetic fields in the star forming regions of the Carina-Sagittarius spiral arm tangentJul 15 2012We present the pilot results of the `MAGMO' project, targeted observations of ground-state hydroxyl masers towards sites of 6.7-GHz methanol maser emission in the Carina-Sagittarius spiral arm tangent, Galactic longitudes 280 degrees to 295 degrees. The ... More
Time-Varying alpha and Particle PhysicsDec 04 2001Jan 09 2002We argue that models in which an observable variation of the fine structure constant is explained by motion of a cosmic scalar field, are not stable under renormalization, and require massive fine tuning that cannot be explained by any known mechanism. ... More
Inflating with the QCD AxionFeb 21 2005Sep 24 2005We show that the QCD axion can drive inflation via a series of tunneling events. For axion models with a softly broken $Z_N$ symmetry, the axion potential has a series of $N$ local minima and may be modeled by a tilted cosine. Chain inflation results ... More
Hawking temperature in the tunneling pictureAug 15 2006Sep 24 2006We examine Hawking radiation from a Schwarzschild black hole in several reference frames using the quasi-classical tunneling picture. It is shown that when one uses, $\Gamma \propto \exp(Im [\oint p dr])$, rather than, $\Gamma \propto \exp(2 Im [\int ... More
Partitioning the Primes and Efficient Non-trivial Factor Generation using the Least Odd Partition Identity in Conjunction with Dirichlet Linear Progressions and the Reduced Residue System Modulo 18Jun 25 2019Jun 27 2019In this work we introduce the numerical constant, LOPI, N LOPI is congruent to LOPI mod 18, equal to the lowest odd partition identity in conjunction with the reduced residue system Modulo 18, a complete disjoint covering residue system when considered ... More
Supershells as Molecular Cloud Factories: Parsec Resolution Observations of HI and 12CO(J=1-0) in GSH 287+04-17 and GSH 277+00+36Dec 24 2010We present parsec-scale resolution observations of the atomic and molecular ISM in two Galactic supershells, GSH 287+04-17 and GSH 277+00+36. HI synthesis images from the Australia Telescope Compact Array are combined with 12CO(J=1-0) data from the NANTEN ... More
The Supershell-Molecular Cloud Connection in the Milky Way and BeyondSep 30 2012The role of large-scale stellar feedback in the formation of molecular clouds has been investigated observationally by examining the relationship between HI and 12CO(J=1-0) in supershells. Detailed parsec-resolution case studies of two Milky Way supershells ... More
HI Absorption Toward HII Regions at Small Galactic LongitudesAug 13 2013We make a comprehensive study of HI absorption toward HII regions located within Galactic longitudes less than 10 degrees. Structures in the extreme inner Galaxy are traced using the longitude-velocity space distribution of this absorption. We find significant ... More
GSH23.0-0.7+117, a neutral hydrogen shell in the inner GalaxyFeb 19 2004GSH23.0-0.7+117 is a well-defined neutral hydrogen shell discovered in the VLA Galactic Plane Survey (VGPS). Only the blueshifted side of the shell was detected. The expansion velocity and systemic velocity were determined through the systematic behavior ... More
Discussion of the Paper SPE-187038-MS: Fracture Closure Stress: Reexamining Field and Laboratory Experiments of Fracture Closure Using Modern Interpretation MethodologiesApr 15 2019In recent years, there has been discussion in the literature regarding methods of estimating the magnitude of the minimum principal stress from subsurface fracture injection tests, commonly called Diagnostic Fracture Injection Tests (DFITs). McClure et ... More
Representational Distance Learning for Deep Neural NetworksNov 12 2015Nov 07 2016Deep neural networks (DNNs) provide useful models of visual representational transformations. We present a method that enables a DNN (student) to learn from the internal representational spaces of a reference model (teacher), which could be another DNN ... More
Intersection homology duality and pairings: singular, PL, and sheaf-theoreticDec 27 2018Feb 05 2019We compare the sheaf-theoretic and singular chain versions of Poincare duality for intersection homology, showing that they are isomorphic via naturally defined maps. Similarly, we demonstrate the existence of canonical isomorphisms between the singular ... More
Observational $5-20μ$m Interstellar Extinction Curves Toward Star-Forming Regions Derived from Spitzer IRS SpectraOct 24 2008Jun 30 2009Using \emph{Spitzer} Infrared Spectrograph observations of G0--M4 III stars behind dark clouds, I construct $5-20\mu$m empirical extinction curves for $0.3\leq A_K<7$, which is equivalent to $A_V$ between $\approx$ 3 and 50. For $A_K<1$ the curve appears ... More
ResFrac Technical WriteupApr 06 2018May 28 2019ResFrac is a combined hydraulic fracturing, reservoir, and hydraulic fracturing simulator. It describes multiphase fluid flow (black oil or compositional), proppant transport, transport of non-Newtonian fluid additives, and thermal transport. It also ... More
On semisimplicial sets satisfying the Kan conditionOct 20 2012A semisimplicial set has face maps but not degeneracies. A basic fact, due to Rourke and Sanderson, is that a semisimplicial set satisfying the Kan condition can be given a simplicial structure. The present paper gives a combinatorial proof of this fact ... More
The Infrared Properties of Submillimeter Galaxies: Clues From Ultra-Deep 70 Micron ImagingDec 19 2006Dec 20 2006We present 70 micron properties of submillimeter galaxies (SMGs) in the Great Observatories Origins Deep Survey (GOODS) North field. Out of thirty submillimeter galaxies (S_850 > 2 mJy) in the central GOODS-N region, we find two with secure 70 micron ... More
The Deep Diffuse Extragalactic Radio Sky at 1.75 GHzAug 18 2014Dec 05 2014We present a study of diffuse extragalactic radio emission at $1.75\,$GHz from part of the ELAIS-S1 field using the Australia Telescope Compact Array. The resulting mosaic is $2.46\,$deg$^2$, with a roughly constant noise region of $0.61\,$deg$^2$ used ... More
Multiplicative properties of Quinn spectraJul 14 2009Mar 10 2011We give a simple sufficient condition for Quinn's "bordism-type spectra" to be weakly equivalent to strictly associative ring spectra. We also show that Poincare bordism and symmetric L-theory are naturally weakly equivalent to monoidal functors. Part ... More
Discovery of a Radio Supernova Remnant and Non-thermal X-rays Coincident with the TeV Source HESS J1813-178May 07 2005Jul 13 2005We present the discovery of non-thermal radio and X-ray emission positionally coincident with the TeV $\gamma$-ray source HESS J1813--178. We demonstrate that the non-thermal radio emission is due to a young shell-type supernova remnant (SNR) G12.8--0.0, ... More
Antisymmetry in the Faraday Rotation Sky Caused by a Nearby Magnetized BubbleNov 01 2010Rotation measures of pulsars and extragalactic point sources have been known to reveal large-scale antisymmetries in the Faraday rotation sky with respect to the Galactic plane and halo that have been interpreted as signatures of the mean magnetic field ... More
Investigating surface loss effects in superconducting transmon qubitsMay 25 2016Superconducting qubits are sensitive to a variety of loss mechanisms including dielectric loss from interfaces. By changing the physical footprint of the qubit it is possible to modulate sensitivity to surface loss. Here we show a systematic study of ... More
Spitzer IRS Spectra and Envelope Models of Class I Protostars in TaurusNov 26 2007We present Spitzer Infrared Spectrograph spectra of 28 Class I protostars in the Taurus star-forming region. The 5 to 36 micron spectra reveal excess emission from the inner regions of the envelope and accretion disk surrounding these predecessors of ... More
Analytical determination of participation in superconducting coplanar architecturesDec 14 2017Jun 18 2018Superconducting qubits are sensitive to a variety of loss mechanisms which include dielectric loss from interfaces. The calculation of participation near the key interfaces of planar designs can be accomplished through an analytical description of the ... More
GASKAP -- The Galactic ASKAP SurveyJul 04 2012A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (HI) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey ... More
Complex Faraday depth structure of Active Galactic Nuclei as revealed by broadband radio polarimetryJan 16 2012Feb 10 2012We present a detailed study of the Faraday depth structure of four bright (> 1 Jy), strongly polarized, unresolved, radio-loud quasars. The Australia Telescope Compact Array (ATCA) was used to observe these sources with 2 GHz of instantaneous bandwidth ... More
Experimental demonstration of a resonator-induced phase gate in a multi-qubit circuit QED systemJun 02 2016The resonator-induced phase (RIP) gate is a multi-qubit entangling gate that allows a high degree of flexibility in qubit frequencies, making it attractive for quantum operations in large-scale architectures. We experimentally realize the RIP gate with ... More
The L-Homology Fundamental Class for IP-Spaces and the Stratified Novikov ConjectureApr 22 2014Oct 23 2018An IP-space is a pseudomanifold whose defining local properties imply that its middle perversity global intersection homology groups satisfy Poincar\'e duality integrally. We show that the symmetric signature induces a map of Quinn spectra from IP bordism ... More
Multivariable cochain operations and little n-cubesJun 04 2001Dec 05 2002This is a revision of a paper first posted June 4, 2001. It will appear in the Journal of the AMS. In this paper we construct a small $E_\infty$ chain operad $\S$ which acts naturally on the normalized cochains $S^*X$ of a topological space. We also construct, ... More
Bulk and surface loss in superconducting transmon qubitsSep 13 2015Decoherence of superconducting transmon qubits is purported to be consistent with surface loss from two-level systems on the substrate surface. Here, we present a study of surface loss in transmon devices, explicitly designed to have varying sensitivities ... More
Cosimplicial Objects and little n-cubes. INov 23 2002Feb 07 2004In this paper we show that if a cosimplicial space or spectrum $X^\bullet$ has a certain kind of combinatorial structure (we call it a $\Xi^n$-structure) then the total space of $X^\b$ has an action of a certain operad which is weakly equivalent to the ... More
Anisotropy in the Hubble constant as observed in the HST Extragalactic Distance Scale Key Project resultsMar 21 2007Based on general relativity, it can be argued that deviations from a uniform Hubble flow should be thought of as variations in the Universe's expansion velocity field, rather than being thought of as peculiar velocities with respect to a uniformly expanding ... More
Operads and cosimplicial objects: an introductionFeb 07 2004This paper is an introduction to a series of papers in which we give combinatorial models for certain important operads (including A-infinity and E-infinity operads, the little n-cubes operads, and the framed little disks operad) and combinatorial conditions ... More
An HI interstellar bubble surrounding WR85 and RCW118Jul 20 2005We analyze the distribution of the interstellar matter in the environs of the Wolf-Rayet star LSS3982 (= WR85, WN6+OB?) linked to the optical ring nebula RCW118. Our study is based on neutral hydrogen 21cm-line data belonging to the Southern Galactic ... More
Constraints on the distance to SGR 1806-20 from HI absorptionMar 08 2005Aug 04 2005The giant flare detected from the magnetar SGR 1806-20 on 2004 December 27 had a fluence more than 100 times higher than the only two other SGR flares ever recorded. Whereas the fluence is independent of distance, an estimate for the luminosity of the ... More
Milky Way Kinematics: Measurements at the Subcentral Point of the Fourth QuadrantAug 07 2007We use atomic hydrogen (HI) data from the Southern Galactic Plane Survey to study the kinematics of the fourth quadrant of the Milky Way. By measuring the terminal velocity as a function of longitude throughout the fourth Galactic quadrant we have derived ... More
Cosmological versions of Vaidya's radiating stellar exterior, an accelerating reference frame, and Kinnersley's photon rocketSep 20 2007Sep 21 2008The spacetimes for Vaidya's radiating stellar exterior and Kinnersley's photon rocket in a cosmological background are obtained by performing the same conformal transformation as is used to obtain the Robertson-Walker metric from Minkowski spacetime. ... More
A solution of Deligne's conjectureOct 24 1999Feb 02 2001Deligne asked in 1993 whether the Hochschild cochain complex of an associative ring has a natural action by the singular chains of the little 2-cubes operad. In this paper we give an affirmative answer to this question. We also show that the topological ... More
GASS: The Parkes Galactic All-Sky Survey. II. Stray-Radiation Correction and Second Data ReleaseJul 05 2010Jul 07 2010The Parkes Galactic All-Sky Survey (GASS) is a survey of Galactic atomic hydrogen (HI) emission in the southern sky observed with the Parkes 64-m Radio Telescope. The first data release was published by McClure-Griffiths et al. (2009). We remove instrumental ... More
GMIMS: The Global Magneto-Ionic Medium SurveyDec 12 2008The Global Magneto-Ionic Medium Survey (GMIMS) is a project to map the diffuse polarized emission over the entire sky, Northern and Southern hemispheres, from 300 MHz to 1.8 GHz. With an angular resolution of 30 - 60 arcmin and a frequency resolution ... More
The Southern HII Region Discovery Survey (SHRDS): Pilot SurveyMay 24 2017The Southern HII Region Discovery Survey (SHRDS) is a survey of the third and fourth quadrants of the Galactic plane that will detect radio recombination line and continuum emission at cm-wavelengths from several hundred HII region candidates using the ... More
The $Spitzer$ infrared spectrograph survey of protoplanetary disks in Orion A: I. disk propertiesApr 27 2016We present our investigation of 319 Class II objects in Orion A observed by $Spitzer$/IRS. We also present the follow-up observation of 120 of these Class II objects in Orion A from IRTF/SpeX. We measure continuum spectral indices, equivalent widths, ... More
A Numerical Formulation for Simulating Free-Surface HydrodynamicsOct 07 2014Cartesian-grid methods in combination with immersed-body and volume-of-fluid methods are ideally suited for simulating breaking waves around ships. A surface panelization of the ship hull is used as input to impose body-boundary conditions on a three-dimensional ... More
Tidal evolution of the Moon from a high-obliquity, high-angular-momentum EarthFeb 09 2018In the giant impact hypothesis for lunar origin, the Moon accreted from an equatorial circum-terrestrial disk; however the current lunar orbital inclination of 5 degrees requires a subsequent dynamical process that is still debated. In addition, the giant ... More
Comparison of VCA and GAEE algorithms for Endmember ExtractionMay 27 2018Endmember Extraction is a critical step in hyperspectral image analysis and classification. It is an useful method to decompose a mixed spectrum into a collection of spectra and their corresponding proportions. In this paper, we solve a linear endmember ... More
Predicting Merger-Induced Gas Motions in Lambda-CDM Galaxy ClustersJul 08 2013Oct 01 2013In the hierarchical structure formation model, clusters of galaxies form through a sequence of mergers and continuous mass accretion, which generate significant random gas motions especially in their outskirts where material is actively accreting. Non-thermal ... More
A Temporary Epoch of Stalled Spin-Down for Low-Mass Stars: Insights from NGC 6811 with Gaia and KeplerMay 16 2019May 25 2019Stellar rotation was proposed as a potential age diagnostic that is precise, simple, and applicable to a broad range of low-mass stars ($\leq$1 $M_\odot$). Unfortunately, rotation period $(P_{\rm rot})$ measurements of low-mass members of open clusters ... More
A search for radius inflation among active M-dwarfs in PraesepeNov 27 2018Rotation periods from Kepler K2 are combined with projected rotation velocities from the WIYN 3.5-m telescope, to determine projected radii for fast-rotating, low-mass ($0.15 \leq M/M_{\odot} \leq 0.6$) members of the Praesepe cluster. A maximum likelihood ... More
Surface Potentials and Layer Charge Distributions in Few-Layer Graphene FilmsJul 10 2008Graphene-derived nanomaterials are emerging as ideal candidates for postsilicon electronics. Elucidating the electronic interaction between an insulating substrate and few-layer graphene (FLG) films is crucial for device applications. Here, we report ... More
Multimodal Sparse Coding for Event DetectionMay 17 2016Unsupervised feature learning methods have proven effective for classification tasks based on a single modality. We present multimodal sparse coding for learning feature representations shared across multiple modalities. The shared representations are ... More
Discovery of Shocked Molecular Clouds Associated with the Shell-Type Supernova Remnant RX J0046.5$-$7308 in the Small Magellanic CloudApr 09 2019Aug 03 2019RX J0046.5$-$7308 is a shell-type supernova remnant (SNR) in the Small Magellanic Cloud (SMC). We carried out new $^{12}$CO($J$ = 1-0, 3-2) observations toward the SNR using Mopra and the Atacama Submillimeter Telescope Experiment. We found eight molecular ... More
Scaling limits of Markov branching trees and Galton-Watson trees conditioned on the number of vertices with out-degree in a given setMay 12 2011Sep 22 2013We generalize recent results of Haas and Miermont to obtain scaling limits of Markov branching trees whose size is specified by the number of nodes whose out-degree lies in a given set. We then show that this implies that the scaling limit of finite variance ... More
Explicit points on the Legendre curve IIIJun 25 2014Nov 24 2014We continue our study of the Legendre elliptic curve y^2=x(x+1)(x+t) over function fields K_d=F_p(\mu_d,t^{1/d}). When d=p^f+1, we have previously exhibited explicit points generating a subgroup V_d of E(K_d) of rank d-2 and of finite, p-power index. ... More
Many-anyon trial statesAug 17 2016The problem of bounding the (abelian) many-anyon ground-state energy from above, with a dependence on the statistics parameter which matches that of currently available lower bounds, is reduced to studying the correlation functions of Moore-Read (Pfaffian) ... More
Topological Electric ChargeJan 10 1997By treating magnetic charge as a gauge symmetry through the introduction of a ``magnetic'' pseudo four-vector potential, it is shown that it is possible, using the 't Hooft-Polyakov construction, to obtain a topological electric charge. The mass of this ... More
Gravitational trapping potential with arbitrary extra dimensionsMar 28 2004Jul 27 2004We extend a recently discovered, non-singular 6 dimensional brane, solution to D=4+n dimensions. As with the previous 6D solution the present solution provides a gravitational trapping mechanism for fields of spin 0, 1/2, 1 and 2. There is an important ... More
Elliptic curves and analogies between number fields and function fieldsMay 22 2003Jun 02 2003The well-known analogies between number fields and function fields have led to the transposition of many problems from one domain to the other. In this paper, we will discuss traffic of this sort, in both directions, in the theory of elliptic curves. ... More
Cardinal Characteristics of Models of Set TheoryNov 13 2018We continue our investigation =of Shelah's interpretability orders $\trianglelefteq^*_\kappa$ as well as the new orders $\trianglelefteq^\times_\kappa$. In particular, we give streamlined proofs of the existence of minimal unstable, unsimple and nonlow ... More
Pseudosaturation and the Interpretability OrdersNov 13 2018We streamline treatments of the interpretability orders $\trianglelefteq^*_\kappa$ of Shelah, the key new notion being that of pseudosaturation. Extending work of Malliaris and Shelah, we classify the interpretability orders on the stable theories. As ... More
L-functions with large analytic rank and abelian varieties with large algebraic rank over function fieldsSep 25 2006The goal of this paper is to explain how a simple but apparently new fact of linear algebra together with the cohomological interpretation of L-functions allows one to produce many examples of L-functions over function fields vanishing to high order at ... More
Geometric extensions of many-particle Hardy inequalitiesJan 13 2011Oct 12 2014Certain many-particle Hardy inequalities are derived in a simple and systematic way using the so-called ground state representation for the Laplacian on a subdomain of $\mathbb{R}^n$. This includes geometric extensions of the standard Hardy inequalities ... More
Weighted Supermembrane Toy ModelApr 29 2009Mar 25 2010A weighted Hilbert space approach to the study of zero-energy states of supersymmetric matrix models is introduced. Applied to a related but technically simpler model, it is shown that the spectrum of the corresponding weighted Hamiltonian simplifies ... More
The evolution of galaxy formationDec 01 2011Our history of understanding galaxy formation could be traced through the development of individual ideas. A cynic might be tempted to suggest that new catchphrases are developed at a faster rate than genuine progress is made.
CMB ANISOTROPIES: AN OVERVIEWFeb 02 1995A brief outline of the current status of CMB anisotropies and what they might mean, heavily biased towards the perspective of Berkeley theorists. Based on a talk presented at the 17th Texas Symposium on Relativistic Astrophysics held in Munich, December ... More
Many-anyon trial statesAug 17 2016Dec 05 2016The problem of bounding the (abelian) many-anyon ground-state energy from above, with a dependence on the statistics parameter which matches that of currently available lower bounds, is reduced to studying the correlation functions of Moore-Read (Pfaffian) ... More
Discovery of Shocked Molecular Clouds Associated with the Shell-Type Supernova Remnant RX J0046.5$-$7308 in the Small Magellanic CloudApr 09 2019Jun 18 2019RX J0046.5$-$7308 is a shell-type supernova remnant (SNR) in the Small Magellanic Cloud (SMC). We carried out new $^{12}$CO($J$ = 1-0, 3-2) observations toward the SNR using Mopra and ASTE. We found eight molecular clouds (A-H) along the X-ray shell of ... More
Discovery of Shocked Molecular Clouds Associated with the Shell-Type Supernova Remnant RX J0046.5$-$7308 in the Small Magellanic CloudApr 09 2019May 31 2019RX J0046.5$-$7308 is a shell-type supernova remnant (SNR) in the Small Magellanic Cloud (SMC). We carried out new $^{12}$CO($J$ = 1-0, 3-2) observations toward the SNR using Mopra and ASTE. We found eight molecular clouds (A-H) along the X-ray shell of ... More
Determinants of Seidel matrices and a conjecture of GhorbaniApr 09 2019Let $G_n$ be a simple graph on $V_n=\{v_1,\dots, v_n\}$. The Seidel matrix $S(G_n)$ of $G_n$ is the $n\times n$ matrix whose $(ij)$'th entry, for $i\neq j$ is $-1$ if $v_i\sim v_j$ and $1$ otherwise, and whose diagonal entries are $0$. We show that the ... More
Elliptic curves with large rank over function fieldsSep 21 2001May 20 2004We produce explicit elliptic curves over \Bbb F_p(t) whose Mordell-Weil groups have arbitrarily large rank. Our method is to prove the conjecture of Birch and Swinnerton-Dyer for these curves (or rather the Tate conjecture for related elliptic surfaces) ... More
Geometric non-vanishingMay 22 2003May 13 2004We consider $L$-functions attached to representations of the Galois group of the function field of a curve over a finite field. Under mild tameness hypotheses, we prove non-vanishing results for twists of these $L$-functions by characters of order prime ... More
K2 rotation periods for low-mass Hyads and a quantitative comparison of the distribution of slow rotators in the Hyades and PraesepeMay 16 2019We analyze K2 light curves for 132 low-mass ($1\ \gtrsim\ M_*\ \gtrsim\ 0.1$~${M_{\odot}}$) members of the 600--800~Myr-old Hyades cluster and measure rotation periods ($P_{rot}$) for 116 of these stars. These include 93 stars with no prior $P_{rot}$ ... More
Henry Eyring: Statistical Mechanics, Significant Structure Theory, and the Inductive-Deductive MethodJan 25 2010Henry Eyring was, and still is, a towering figure in science. Some aspects of his life and science, beginning in Mexico and continuing in Arizona, California, Wisconsin, Germany, Princeton, and finally Utah, are reviewed here. Eyring moved gradually from ... More
Simpler near-optimal controllers through direct supervisionAug 20 2009The method of generalized Hamilton-Jacobi-Bellman equations (GHJB) is a powerful way of creating near-optimal controllers by learning. It is based on the fact that if we have a feedback controller, and we learn to compute the gradient grad-J of its cost-to-go ... More
Keisler's Order is Not Linear, Assuming a SupercompactFeb 04 2017We show that Keisler's order is not linear, assuming the existence of a supercompact cardinal.
New physics from the Cosmic Microwave BackgroundNov 17 1999I review the present status of the Cosmic Microwave Background, with some emphasis on the current and future implications for particle physics. Conclusions are: gravitational instability in a dark matter dominated universe grew today's structure; the ... More
Function fields and random matricesFeb 17 2010This is a survey article written for a workshop on L-functions and random matrix theory at the Newton Institute in July, 2004. The goal is to give some insight into how well-distributed sets of matrices in classical groups arise from families of $L$-functions ... More
Jacobi sums, Fermat Jacobians, and ranks of abelian varieties over towers of function fieldsSep 26 2006Our goal in this note is to give a number of examples of abelian varieties over function fields k(t) which have bounded ranks in towers of extensions such as k(t^{1/d}) for varying d. Along the way we prove some new results on Fermat curves which may ... More
Explicit points on the Legendre curve IIIJun 25 2014May 24 2017We continue our study of the Legendre elliptic curve $y^2=x(x+1)(x+t)$ over function fields $K_d=\mathbf{F}_p(\mu_d,t^{1/d})$. When $d=p^f+1$, we have previously exhibited explicit points generating a subgroup $V_d$ of $E(K_d)$ of rank $d-2$ and of finite, ... More
Conductors of l-adic representationsJul 17 2013Jul 07 2015We give a new formula for the Artin conductor of an $\ell$-adic representation of the Weil group of a local field of residue characteristic $p\neq\ell$.
Lehmer's Problem for compact abelian groupsMar 23 2003Jan 07 2004We formulate Lehmer's Problem about the Mahler measure of polynomials for general compact abelian groups, introducing a Lehmer constant for each such group. We show that all nontrivial connected compact groups have the same Lehmer constant, and conjecture ... More
Assouad type dimensions for partially affine spongesOct 13 2016Recently self-affine sponges have been shown to be interesting examples and counter-examples to several previously open problems. One class of recently discovered sponges are partially affine Bedford-McMullen sponges whose Assouad type dimensions cannot ... More
CRM lectures on curves and Jacobians over function fieldsMar 26 2012Oct 28 2012These are notes related to a 12-hour course of lectures given at the Centre de Recerca Mathem\`atica near Barcelona in February, 2010. The aim of the course was to explain results on curves and their Jacobians over function fields, with emphasis on the ... More
On Mordell-Weil groups of Jacobians over function fieldsFeb 17 2010Feb 18 2011We study the arithmetic of abelian varieties over $K=k(t)$ where $k$ is an arbitrary field. The main result relates Mordell-Weil groups of certain Jacobians over $K$ to homomorphisms of other Jacobians over $k$. Our methods also yield completely explicit ... More
A Streamlined Proof of $\mathfrak{p}=\mathfrak{t}$Oct 22 2018We streamline Malliaris and Shelah's proof that $\mathfrak{p} = \mathfrak{t}$. In particular, we replace cofinality spectrum problems with models of $ZFC^-$, and we eliminate the use of peculiar cuts.
Methods of modern mathematical physics: Uncertainty and exclusion principles in quantum mechanicsMay 08 2018These are lecture notes for a master-level course given at KTH, Stockholm, in the spring of 2017, with the primary aim of proving the stability of matter from first principles using modern mathematical methods in many-body quantum mechanics. General quantitative ... More
Rational curves on elliptic surfacesJul 29 2014Aug 14 2014We prove that a very general elliptic surface $\mathcal{E}\to\mathbb{P}^1$ over the complex numbers with a section and with geometric genus $p_g\ge2$ contains no rational curves other than the section and components of singular fibers. Equivalently, if ... More
Park City lectures on elliptic curves over function fieldsJan 10 2011These are the notes from a course of five lectures at the 2009 Park City Math Institute. The focus is on elliptic curves over function fields over finite fields. In the first three lectures, we explain the main classical results (mainly due to Tate) on ... More
A detailed study of the interstellar protons toward the TeV $γ$-ray SNR RX J0852.0$-$4622 (G266.2$-$1.2, Vela Jr.); a third case of the $γ$-rays and ISM spatial correspondenceAug 26 2017Oct 07 2017We present a new analysis of the interstellar protons toward the TeV $\gamma$-ray SNR RX J0852.0$-$4622 (G266.2$-$1.2, Vela Jr.). We used the NANTEN2 $^{12}$CO($J$ = 1-0) and ATCA & Parkes HI datasets in order to derive the molecular and atomic gas associated ... More
Identifying potentially induced seismicity and assessing statistical significance in Oklahoma and CaliforniaNov 10 2016In this study, we develop a statistical method for identifying induced seismicity from large datasets and apply the method to decades of wastewater disposal and seismicity data in California and Oklahoma. The method is robust against a variety of potential ... More
Milky Way Disk-Halo Transition in HI: Properties of the Cloud PopulationAug 16 2010Using 21cm HI observations from the Parkes Radio Telescope's Galactic All-Sky Survey, we measure 255 HI clouds in the lower Galactic halo that are located near the tangent points at 16.9 < l < 35.3 degrees and |b| < 20 degrees. The clouds have a median ... More
Measuring Catastrophic Forgetting in Neural NetworksAug 07 2017Nov 09 2017Deep neural networks are used in many state-of-the-art systems for machine perception. Once a network is trained to do a specific task, e.g., bird classification, it cannot easily be trained to do new tasks, e.g., incrementally learning to recognize additional ... More
A panoramic view of the Milky Way HI gasOct 30 2009Imaging of galaxies to study the interstellar medium on scales of a few pc is difficult. However, for the Milky Way galaxy two major Galactic all sky HI 21-cm line surveys will become available soon with unprecedented quality. We present the Galactic ... More
HI 21 cm Emission Line Study of Southern Galactic Supernova RemnantsJun 21 2004We have searched for HI 21 cm line emission from shocked atomic gas associated with southern supernova remnants (SNRs) using data from the Southern Galactic Plane Survey. Among the 97 sources studied, we have detected 10 SNRs with high-velocity HI emission ... More
HI Study of Southern Galactic Supernova RemnantsNov 06 2003We briefly summarize the survey of HI 21 cm emission lines to search for shocked atomic gas associated with Galactic supernova remnants (SNRs) in the southern sky. For G347.3-0.5, we discuss the distance to the SNR and the implications of the HI results. ... More
Investigating the Origins of Spiral Structure in Disk Galaxies through a Multiwavelength StudyJul 16 2019The density-wave theory of spiral structure proposes that star formation occurs in or near a spiral-shaped region of higher density that rotates rigidly within the galactic disk at a fixed pattern speed. In most interpretations of this theory, newborn ... 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
The multiplicity of 250-$μ$m Herschel sources in the COSMOS fieldApr 29 2016We investigate the multiplicity of extragalactic sources detected by the Herschel Space Observatory in the COSMOS field. Using 3.6- and 24-$\mu$m catalogues, in conjunction with 250-$\mu$m data from Herschel, we seek to determine if a significant fraction ... More