Results for "Andrew Blain"

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The Nature of Faint Submillimeter GalaxiesAug 16 2000We summarise the main results on the faint submillimeter (submm) galaxy population which have come from the SCUBA Cluster Lens Survey. We detail our current understanding of the characteristics of these submm-selected galaxies across wavebands from X-rays ... More
Submillimeter-selected galaxiesAug 10 1999The first generation of submillimeter(submm)-wave surveys are being carried out using the 450/850-micron SCUBA camera at the JCMT on Mauna Kea. These surveys are potentially sensitive to galaxies at very high redshift, and the galaxies that have been ... More
The history of starburst galaxiesNov 21 2000Dusty galaxies with luminosities in excess of 10^11 solar luminosities have been detected out to redshifts of about unity by the Infrared Space Observatory (ISO), and to higher redshifts using millimetre(mm)- and submm-wave cameras on ground-based telescopes. ... More
Prospects for future far-infrared/submillimeter studies of the high-redshift UniverseAug 30 2000Observations made using COBE, SCUBA, ISO and MAMBO have provided a reasonable working knowledge of both the intensity of the submm and far-infrared background radiation and the source counts of luminous high-redshift dusty galaxies. However, because there ... More
Dust temperature and the submillimeter-radio flux density ratio as a redshift indicatorMay 19 1999It is difficult to identify the distant galaxies selected in existing submillimeter (submm)-wave surveys, because their positional accuracy is only several arcseconds. Currently, centimeter-wave VLA observations are required in order to determine sub-arcsec ... More
The Discovery of Submillimeter GalaxiesFeb 10 2003I briefly describe some results about luminous distant dusty galaxies obtained in the 5 years since sensitive two-dimensional bolometer array cameras became available. The key requirements for making additional progress in understanding the properties ... More
Galactic morning: the Atacama Large Millimeter Array (ALMA) and the evolution of galaxiesNov 24 1999The importance of the Atacama Large Millimeter Array (ALMA) to the study of high-redshift dusty gas-rich galaxies is described. ALMA will have dramatically greater sensitivity and angular resolution than existing millimetre(mm) and submm-wave telescopes. ... More
Future millimeter, submillimeter and far-infrared surveys and their successful follow upJun 08 1999Dec 15 1999The first unbiased surveys for high-redshift galaxies in the submillimeter (submm) and far-infrared (FIR) wavebands have been made over the last two years. When combined with the intensity of extragalactic background radiation in the same wavebands, we ... More
Submillimetre-wave surveys: first results and prospectsJun 29 1998Aug 11 1998The population of distant dusty submm-luminous galaxies was first detected last year (Smail, Ivison and Blain 1997). Forms of evolution required to account for both this population and the intensity of background radiation have now been determined (Blain, ... More
Gravitational lensing and the Sunyaev-Zel'dovich effect in the millimetre/submillimetre wavebandJan 12 1998The intensity of the cosmic microwave background radiation in the fields of clusters of galaxies is modified by inverse Compton scattering in the hot intracluster gas - the Sunyaev-Zel'dovich (SZ) effect. The effect is expected to be most pronounced at ... More
SCUBA deep fields and source confusionNov 26 2000Deep submillimetre(submm)-wave surveys made over the last three years using the SCUBA camera at the 15-m James Clerk Maxwell Telescope (JCMT) have revealed a new population of very luminous high-redshift galaxies. The properties of this population, and ... More
A gravitational lens survey with Planck SurveyorJul 14 2000The Planck Surveyor cosmic microwave background (CMB) imaging mission will make very sensitive maps of the whole sky at microwave, millimetre (mm) and sub-mm wavelengths. The steep source counts expected in the highest frequency Planck bands are likely ... More
The differential magnification of high-redshift ultraluminous infrared galaxiesDec 22 1998Feb 08 1999A class of extremely luminous high-redshift galaxies has recently been detected in unbiased submillimetre-wave surveys using the Submillimetre Common-User Bolometer Array (SCUBA) camera at the James Clerk Maxwell Telescope. Most of the luminosity of these ... More
The Planck Surveyor mission and gravitational lensesJan 12 1998An extremely sensitive all-sky survey will be carried out in the millimetre/submillimetre waveband by the forthcoming ESA mission Planck Surveyor. The main scientific goal of the mission is to make very accurate measurements of the spatial power spectrum ... More
Z-machines conference proceeding: Future continuum surveysJul 19 2006A significant population of distant sub-millimeter-selected galaxies (SMGs) with powerful dust continuum emission that matches the luminosity of the brightest QSOs and exceeds that of most extreme local galaxies detected by IRAS, has been known for almost ... More
Detecting gravitational lensing cosmic shear from samples of several galaxies using two-dimensional spectral imagingApr 08 2002Apr 12 2002Studies of weak gravitational lensing by large-scale structures require the measurement of the distortions introduced to the shapes of distant galaxies at the few percent level by anisotropic light deflection along the line of sight. To detect this signal ... More
The ISM at high redshifts: ALMA results and a look to the futureMar 11 2015ALMA is revolutionizing the way we study and understand the astrophysics of galaxies, both as a whole and individually. By exploiting its unique sensitivity and resolution to make spatially and spectrally resolved images of the gas and dust in the interstellar ... More
The differential magnification of high-redshift ultraluminous infrared galaxiesMar 15 1999This proceeding discusses the potential modifications to the mid-infrared spectral energy distribution (SED) of a high-redshift dusty AGN that is graviationally lensed by a foreground galaxy. The mid-infrared colour of a lensed galaxy would typically ... More
Infrared galaxiesDec 15 1998To study large-scale structure in the Universe a full census of the contents are required. This is even more important when the processes of galaxy formation are being investigated. In the last year the population of distant galaxies that emit most of ... More
Exploiting magnification bias in ultradeep submillimetre-wave surveys using ALMAOct 17 2001The surface density of populations of galaxies with steep/shallow source counts is increased/decreased by gravitational lensing magnification. These effects are usually called `magnification bias' and `depletion' respectively. However, if sources are ... More
Selection effects in high-redshift submillimeter surveys and pointed observationsSep 01 2000The results of the first generation of submillimeter-wave surveys have been published. The opening of this new window on the distant Universe has added considerably to our understanding of the galaxy formation process, by revealing a numerous population ... More
Dust temperture and the submillimetre-radio flux density ratio as a redshift indicator for distant galaxiesJun 28 1999Aug 13 1999It is difficult to identify the distant galaxies selected in existing submillimetre-wave surveys, because their positions are known at best to only several arcseconds. Centimetre-wave VLA observations are required in order to determine positions to subarcsecond ... More
Gamma-ray bursts and the history of star formationNov 25 1999Jan 28 2000Popular models for the origin of gamma-ray bursts (GRBs) include short-lived massive stars as the progenitors of the fireballs. Hence the redshift distribution of GRBs should track the cosmic star formation rate of massive stars accurately. A significant ... More
The 60-micron extragalactic background radiation intensity, dust-enshrouded AGNs and the assembly of groups and clusters of galaxiesFeb 06 2002Apr 19 2002Submillimetre observations reveal a cosmologically significant population of high-redshift dust-enshrouded galaxies. The form of evolution inferred for this population can be reconciled easily with COBE FIRAS and DIRBE measurements of the cosmic background ... More
Overdensities of SMGs around WISE-selected, ultra-luminous, high-redshift galaxiesMar 10 2015Submillimetre (submm) observations of WISE-selected, dusty, luminous, high-redshift galaxies have revealed intriguing overdensities around them on arcmin scales. They could be the best signposts of overdense environments on the sky.
Two sub-millimetre bright protoclusters bounding the epoch of peak star formation activitySep 18 2018Sep 26 2018We present James Clerk Maxwell Telescope (JCMT) Submillimetre Common-User Bolometer Array 2 (SCUBA-2) 850 \& 450 $\mu$m observations ($\sigma_{850}\sim0.5$ mJy, $\sigma_{450}\sim5$ mJy) of the HS1549+19 and HS1700+64 survey fields containing two of the ... More
A Theory of Particular SetsMay 07 2019ZFC has sentences that quantify over all sets or all ordinals, without restriction. Some have argued that sentences of this kind lack a determinate meaning. We propose a set theory that avoids this problem by speaking only about particular sets.
Searching for high-redshift centimeter-wave continuum, line and maser emission using the Square Kilometer ArraySep 13 2004We discuss the detection of redshifted line and continuum emission at radio wavelengths using a Square Kilometer Array (SKA), specifically from low-excitation rotational molecular line transitions of CO and HCN (molecular lines), the recombination radiation ... More
Accurate Spectral energy distributions and selection effects for high-redshift dusty galaxies: a new hot population to discover with the Spitzer Space Telescope?Apr 22 2004Jul 03 2004The spectral energy distributions (SEDs) of dust-enshrouded galaxies with powerful restframe far-infrared emission have been constrained by a range of ground-based and space-borne surveys. The IRAS catalog provides a reasonably complete picture of the ... More
Galaxy counts at 450 and 850 micronsAug 03 1999Surveys of the distant Universe have been made using the SCUBA submillimeter(submm)-wave camera at the JCMT. 450- and 850-micron data is taken simultaneously by SCUBA in the same 5-square-arcmin field. Deep 850-micron counts of high-redshift dusty galaxies ... More
Clustering of Submillimeter-Selected GalaxiesMay 03 2004Jul 06 2004Using accurate positions from very deep radio observations to guide multi-object Keck spectroscopy, we have determined a substantially complete redshift distribution for very luminous, distant submillimeter(submm)-selected galaxies (SMGs). A sample of ... More
Submillimetre and far-infrared spectral energy distributions of galaxies: the luminosity-temperature relation and consequences for photometric redshiftsSep 21 2002Nov 14 2002The spectral energy distributions (SEDs) of dusty high-redshift galaxies are poorly sampled in frequency and spatially unresolved. Their form is crucially important for estimating the large luminosities of these galaxies accurately, for providing circumstantial ... More
Deep sub-mm surveys with SCUBAOct 19 1998We review published deep surveys in the submillimeter (sub-mm) regime from the new Sub-millimetre Common User Bolometer Array (SCUBA) on the 15-m James Clerk Maxwell Telescope (JCMT), Mauna Kea, Hawaii. Summarising the number counts of faint sub-mm sources ... More
The birth place of gamma-ray bursts: abundance gradients and constraints on progenitorsDec 06 2001The physics of gamma-ray bursts (GRBs) and their offsets from the centers of their host galaxies are used to investigate the evolutionary state of their progenitors, motivated by the popular idea that GRBs are linked with the cataclysmic collapse of massive ... More
A Submm View of the Universe: Clues to the Formation of Massive GalaxiesNov 12 2003We discuss recent advances in the study of dusty, massive galaxies at z>1 arising from the first extensive spectroscopic surveys.
Gigamasers: the key to the dust-obscured star-formation history of the Universe?Jun 06 2001Jan 04 2002We discuss the possibility of using OH and H2O gigamasers to trace the redshift distribution of luminous, dust-obscured, star-forming galaxies. It has long been thought that ultraluminous, interacting galaxies should host gigamasers due to their vast ... More
Probing the mass distribution in groups of galaxies using gravitational lensingOct 18 2001In this paper, we study gravitational lensing by groups of galaxies. Since groups are abundant and therefore have a large covering fraction on the sky, lensing by groups is likely to be very important observationally. Besides, it has recently become clear ... More
Statistical lensing by galactic discsOct 23 1998Dec 15 1998The high-magnification gravitational lensing cross-section of a galaxy is enhanced significantly if a baryonic disc is embedded in its dark matter halo. We investigate the effects of a population of such disks on the probability of detecting strongly ... More
Rest-frame optical and far-infrared observations of extremely bright Lyman-break galaxy candidates at z ~ 2.5Jun 21 2005Jul 11 2005We have investigated the rest-frame optical and far-infrared properties of a sample of extremely bright candidate Lyman-break galaxies (LBG) identified in the Sloan Digital Sky Survey. Their high ultraviolet luminosities and lack of strong ultraviolet ... More
The Link between Submillimetre Galaxies and Luminous Ellipticals: Near-Infrared IFU Spectroscopy of Submillimetre GalaxiesJun 15 2006We present two-dimensional spectroscopy covering the rest-frame wavelengths of strong optical emission lines in six luminous submillimetre galaxies at z=1.3--2.5. Together with HST ACS and NICMOS imaging we map the dynamics and morphologies of these systems ... More
Submillimeter GalaxiesFeb 12 2002May 30 2002A cosmologically significant population of very luminous high-redshift galaxies has recently been discovered at submm wavelengths. Advances in submm detector technologies have opened this new window on the distant Universe. Here we discuss the properties ... More
The Rest-frame Optical Spectra of SCUBA GalaxiesDec 02 2004We present near-infrared spectroscopy and narrow-band imaging at the wavelength of redshifted H-alpha for a sample of 30 high-redshift, far-infrared luminous galaxies. This sample is selected from surveys in the sub-millimeter, millimeter and radio wavebands ... More
Submm Continuum Surveys for Obscured GalaxiesJun 11 1999We discuss deep surveys in the submm regime using the SCUBA bolometer array on the JCMT. At 850um SCUBA has resolved the bulk of the submm background (SMBR) detected by COBE into discrete sources brighter than 0.5mJy. The on-going identification and characterisation ... More
Deep counts of submillimeter galaxiesDec 22 1998Jan 14 1999We present the counts of luminous submillimeter (sub-mm) galaxies from an analysis of our survey of the distant Universe through lensing clusters, which uses massive cluster lenses with well-constrained mass models to magnify the background sky. This ... More
Dust-obscured star formation and AGN fuelling in hierarchical models of galaxy evolutionJun 18 1999Sep 01 1999A large fraction of the luminous distant submm-wave galaxies recently detected using SCUBA on the JCMT appear to be associated with interacting optical counterparts. We investigate these systems using a simple hierarchical clustering model of galaxy evolution, ... More
Evidence for AGN-driven Outflows in Young Radio QuasarsMar 28 2013We present near-infrared spectra of young radio quasars [P(1.4GHz) ~ 26-27 W/Hz] selected from the Wide-Field Infrared Survey Explorer. The detected objects have typical redshifts of z ~ 1.6-2.5 and bolometric luminosities ~ 10^47 erg/s. Based on the ... More
Taking Census of Massive, Star-Forming Galaxies formed <1 Gyr After the Big BangMar 13 2019Two decades of effort have been poured into both single-dish and interferometric millimeter-wave surveys of the sky to infer the volume density of dusty star-forming galaxies (DSFGs, with SFR>100M$_\odot$ yr$^{-1}$) over cosmic time. Though obscured galaxies ... More
A Telescope Search for Decaying Relic AxionsNov 15 2006Jun 29 2007A search for optical line emission from the two-photon decay of relic axions was conducted in the galaxy clusters Abell 2667 and 2390, using spectra from the VIMOS (Visible Multi-Object Spectrograph) integral field unit at the Very Large Telescope. New ... More
Locating the starburst in the SCUBA galaxy, SMM J14011+0252Oct 03 2001We present new, multi-wavelength, high-resolution imaging of the luminous, submillimeter galaxy, SMM J14011+0252, an interacting starburst at z = 2.56. Our observations comprise optical imaging from the HST, sensitive radio mapping from the VLA and CO ... More
SCUBA's first-born: SMM J02399-0136Jan 26 1999We discuss observations of the submm-selected galaxy, SMM J02399-0136, and what has been learnt about it during the year following its discovery. SMM J02399-0136 was the first distant galaxy detected in submm surveys with SCUBA. Its association with a ... More
Millimetre/submillimetre-wave emission line searches for high-redshift galaxiesNov 07 1999Jan 20 2000The redshifted spectral line radiation emitted from both atomic fine-structure and molecular rotational transitions in the interstellar medium (ISM) of high-redshift galaxies can be detected in the centimetre, millimetre and submillimetre wavebands. Here ... More
Detection of CO from SMM J16359+6612, The Multiply Imaged Submillimeter Galaxy Behind A2218Sep 20 2004We report the detection of CO ($J$=3$\to$2) line emission from all three multiple images (A,B and C) of the intrinsically faint ($\simeq$ 0.8 mJy) submillimeter-selected galaxy SMM J16359+6612. The brightest source of the submm continuum emission (B) ... More
The Discovery of a New Massive Molecular Gas Component Associated with the Submillimeter Galaxy SMM J02399-0136May 18 2018We present CO(1-0), CO(3-2), and CO(7-6) observations using the Green Bank Telescope (GBT) and the Atacama Large Millimeter Array (ALMA) of the z=2.8 sub-millimeter galaxy SMM J02399-0136. This was the first submillimeter-selected galaxy discovered and ... More
Restframe Optical Spectroscopic Classifications for Submillimeter GalaxiesJul 26 2006We report the results of a systematic near-infrared spectroscopic survey using the Subaru, VLT and Keck Telescopes of a sample of high redshift Ultra-luminous Infrared Galaxies (ULIRGs) mainly composed of submillimeter-selected galaxies. Our observations ... More
A Hubble Space Telescope NICMOS and ACS Morphological Study of z~2 Submillimetre GalaxiesFeb 12 2010We present a quantitative morphological analysis using HST NICMOS H160- and ACS I775- band imaging of 25 spectroscopically confirmed submillimetre galaxies (SMGs) which have redshifts between z=0.7-3.4. Our analysis also employs a comparison sample of ... More
The diversity of SCUBA-selected galaxiesNov 05 1999We present extensive observations of a sample of distant, submm galaxies detected in the field of the massive cluster lens, A1835, using SCUBA. Taken in conjunction with earlier observations of other submm-selected sources (Ivison et al. 1998; Smail et ... More
Molecular Gas in a z~2.5 Triply-Imaged, sub-mJy Submillimetre Galaxy Typical of the Cosmic Far-Infrared BackgroundSep 21 2004Jan 27 2005We present the results of observations from the IRAM array of the submm galaxy SMMJ16359+6612 lying at z=2.516 behind the massive cluster A2218. The foreground gravitational lens produces 3 images with a total mag. of 45 of this faint submm galaxy, which ... More
Mapping the Clumpy Structures within Submillimeter Galaxies using Laser-Guide Star Adaptive Optics SpectroscopyFeb 08 2013We present the first integral-field spectroscopic observations of high-redshift submillimeter-selected galaxies (SMGs) using Laser Guide Star Adaptive Optics (LGS-AO). We target H-alpha emission of three SMGs at redshifts z~1.4-2.4 with the OH-Suppressing ... More
SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES): Faint-End Counts at 450 umJul 04 2017Oct 18 2017The SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES) is a three-year JCMT Large Program aiming at reaching the 450 $\mu$m confusion limit in the COSMOS-CANDELS region, to study a representative sample of the high-redshift far-infrared galaxy population ... More
Optical and Near-Infrared Integral Field Spectroscopy of the SCUBA Galaxy N2-850.4Feb 04 2005We present optical and near-infrared integral field spectroscopy of the SCUBA galaxy SMM J163650.43+405734.5 (ELAIS N2 850.4) at z=2.385. We combine Ly-alpha and H-alpha emission line maps and velocity structure with high resolution HST ACS and NICMOS ... More
The Wide-field Infrared Survey Explorer (WISE): Mission Description and Initial On-orbit PerformanceJul 30 2010Nov 09 2010The all sky surveys done by the Palomar Observatory Schmidt, the European Southern Observatory Schmidt, and the United Kingdom Schmidt, the InfraRed Astronomical Satellite and the 2 Micron All Sky Survey have proven to be extremely useful tools for astronomy ... More
Super-Eddington Accretion in the WISE-Selected Extremely Luminous Infrared Galaxy W2246-0526Oct 06 2018We use optical and near-infrared spectroscopy to observe rest-UV emission lines and estimate the black hole mass of WISEA J224607.56-052634.9 (W2246-0526) at z = 4.601, the most luminous hot dust-obscured galaxy yet discovered by WISE. From the broad ... More
Multiply-imaged submm galaxy in a z~2.5 groupMar 08 2004We present observations of a remarkable submillimetre-selected galaxy, SMMJ16359+6612. This distant galaxy lies behind the core of a massive cluster of galaxies, A2218, and is gravitationally lensed by the foreground cluster into three discrete images ... More
Lensed submillimetre-wave foregrounds and the CMBRMar 25 1998Samples of high-redshift galaxies are easy to select in the millimetre/submillimetre (mm/submm) waveband using sensitive telescopes, because their flux density-redshift relations are expected to be flat, and so the selection function is almost redshift-independent ... More
Formulating Categorical Concepts using ClassesJan 25 2018Jul 26 2018We examine the use of classes to formulate several categorical notions. This leads to two proposals: an explicit structure for working with subobjects, and a hierarchy of $k$-classes. We apply the latter to both ordinary and higher categories.
The Properties of Sub-mm Galaxies in Hierarchical ModelsSep 05 2008Sep 11 2008We use the combined GALFORM semi-analytical model of galaxy formation and GRASIL spectrophotometric code to investigate the properties of galaxies selected via their sub-mm emission. Our fiducial model has previously been shown to fit the properties of ... More
Mid-Infrared Spectroscopy of Submillimeter Galaxies: Extended Star Formation in Massive High Redshift GalaxiesMar 24 2009We used the Spitzer Infrared Spectrograph (IRS) to study the mid-IR properties and investigate the energetics of 24 Submillimeter Galaxies (SMGs). This is the largest sample of SMGs observed with Spitzer IRS and covers the full extent of properties of ... More
Mid-Infrared Spectroscopy of High Redshift Submillimeter Galaxies: First ResultsOct 30 2006Dec 24 2006We present mid-infrared spectra of 5 submillimeter galaxies at z=0.65-2.38 taken with the Spitzer Space Telescope. Four of these sources, at z<1.5, have strong PAH features and their composite spectrum is well fitted by an M82-like spectrum with an additional ... More
WISE detections of known QSOs at redshifts greater than sixOct 08 2013We present WISE All-Sky mid-infrared (IR) survey detections of 55% (17/31) of the known QSOs at z>6 from a range of surveys: the SDSS, the CFHT-LS, FIRST, Spitzer and UKIDSS. The WISE catalog thus provides a substantial increase in the quantity of IR ... More
Searching for gravitational lenses in the distant universeOct 14 1997May 19 2004The ESA cornerstone mission The Far-Infrared and Submillimetre Sapce Telescope (FIRST) has the ideal combination of sensitivity and angular resolving power to determine the bright counts of galaxies over a large area of sky in the submillimetre (submm) ... More
A Ghost at $ω_1$Dec 30 2016Jul 25 2018In the final chain of the countable powerset functor, we show that the set at index $\omega_1$, regarded as a transition system, is not strongly extensional because it contains a "ghost" element that has no successor even though its component at each ... More
Logical Modelling of Physarum PolycephalumMay 20 2011We propose a novel model of unconventional computing where a structural part of computation is presented by dynamics of plasmodium of Physarum polycephalum, a large single cell. We sketch a new logical approach combining conventional logic with process ... More
Non-Abelian Cut Constructions and Hyperkähler ModificationsFeb 09 2010We discuss a general framework for cutting constructions and reinterpret in this setting the work on non-Abelian symplectic cuts by Weitsman. We then introduce two analogous non-Abelian modification constructions for hyperk\"ahler manifolds: one modifies ... More
Submillimetre-wave gravitational lenses and cosmologyOct 15 1997One of the most direct routes for investigating the geometry of the Universe is provided by the numbers of strongly magnified gravitationally lensed galaxies as compared with those that are either weakly magnified or de-magnified. In the submillimetre ... More
On Creativity of Elementary Cellular AutomataMay 11 2013We map cell-state transition rules of elementary cellular automata (ECA) onto the cognitive control versus schizotypy spectrum phase space and interpret cellular automaton behaviour in terms of creativity. To implement the mapping we draw analogies between ... More
Bigness in compatible systemsAug 13 2009Apr 21 2010Clozel, Harris and Taylor have recently proved a modularity lifting theorem of the following general form: if rho is an l-adic representation of the absolute Galois group of a number field for which the residual representation rho-bar comes from a modular ... More
Average liar count for degree-2 Frobenius pseudoprimesJul 17 2017In this paper we obtain lower and upper bounds on the average number of liars for the Quadratic Frobenius Pseudoprime Test of Grantham, generalizing arguments of Erd\H{o}s and Pomerance, and Monier. These bounds are provided for both Jacobi symbol plus ... More
Quaternionic Kähler Manifolds of Cohomogeneity OneAug 21 1998Nov 24 1998Classification results are given for (i) compact quaternionic K\"ahler manifolds with a cohomogeneity-one action of a semi-simple group, (ii) certain complete hyperK\"ahler manifolds with a cohomogeneity-two action of a semi-simple group preserving each ... More
Exoplanet Imaging with a Phase-induced Amplitude Apodization Coronagraph III. Hybrid Approach: Optical Design and Diffraction AnalysisDec 15 2005Properly apodized pupils can deliver point spread functions (PSFs) free of Airy rings, and are suitable for high dynamical range imaging of extrasolar terrestrial planets (ETPs). To reach this goal, classical pupil apodization (CPA) unfortunately requires ... More
The temperatures of dust-enshrouded AGNsOct 10 2000A high density of massive dark objects (MDOs), probably supermassive black holes, in the centres of nearby galaxies has been inferred from recent observations. There are various indications that much of the accretion responsible for producing these objects ... More
Strong gravitational lensing by spiral galaxiesJun 04 1998We investigate gravitational lensing by a realistic model of disk galaxies. Most of the mass is contained in a large spherical isothermal dark matter halo, but the potential is modified significantly in the core by a gravitationally-dominant exponential ... More
Failure of flat descent of model structures on module categoriesJan 06 2015We prove that the collection of model structures on (quasicoherent) module categories does not obey flat descent. In particular, it fails to be a separated presheaf, in the fppf topology, on Artin stacks.
Motivic invariants of quivers via dimensional reductionMar 19 2011We provide a reduction formula for the motivic Donaldson-Thomas invariants associated to a quiver with superpotential. The method is valid provided the superpotential has a linear factor, it allows us to compute virtual motives in terms of ordinary motivic ... More
On exploration of geometrically constrained space by medicinal leeches Hirudo verbanaDec 07 2015Leeches are fascinating creatures: they have simple modular nervous circuitry m yet exhibit a rich spectrum of behavioural modes. Leeches could be ideal blue-prints for designing flexible soft robots which are modular, multi-functional, fault-tolerant, ... More
Slime mould electronic oscillatorsMar 28 2014We construct electronic oscillator from acellular slime mould Physarum polycephalum. The slime mould oscillator is made of two electrodes connected by a protoplasmic tube of the living slime mould. A protoplasmic tube has an average resistance of 3~MOhm. ... More
Slimy hairs: Hair sensors made with slime mouldJun 12 2013Slime mould Physarum polycephalum is a large single cell visible by unaided eye. We design a slime mould implementation of a tactile hair, where the slime mould responds to repeated deflection of hair by an immediate high-amplitude spike and a prolonged ... More
Hot Ice ComputerAug 30 2009We experimentally demonstrate that supersaturated solution of sodium acetate, commonly called 'hot ice', is a massively-parallel unconventional computer. In the hot ice computer data are represented by a spatial configuration of crystallization induction ... More
Towards Physarum robots: computing and manipulating on water surfaceApr 13 2008Plasmodium of Physarym polycephalum is an ideal biological substrate for implementing concurrent and parallel computation, including combinatorial geometry and optimization on graphs. We report results of scoping experiments on Physarum computing in conditions ... More
How Bayesian Analysis Cracked the Red-State, Blue-State ProblemMay 19 2014In the United States as in other countries, political and economic divisions cut along geographic and demographic lines. Richer people are more likely to vote for Republican candidates while poorer voters lean Democratic; this is consistent with the positions ... More
"How many zombies do you know?" Using indirect survey methods to measure alien attacks and outbreaks of the undeadMar 31 2010The zombie menace has so far been studied only qualitatively or through the use of mathematical models without empirical content. We propose to use a new tool in survey research to allow zombies to be studied indirectly without risk to the interviewers. ... More
Bayesian Statistics Then and NowDec 07 2010Discussion of "The Future of Indirect Evidence" by Bradley Efron [arXiv:1012.1161]
Canonical bases and the decomposition matrices of Ariki--Koike algebrasJul 05 1996Jan 07 1999This paper has been withdrawn because of a gap in the proof of Lemma 3.10. The main reults in this paper have now been proved, and extended in the following papers: S. Ariki and A. Mathas, The number of simple modules of the Hecke algebras of type G(r,1,n) ... More
The evolution of free wave packetsDec 31 2007We discuss four general features of force-free evolution: (1) The spatial spread of any packet changes with time in a very simple way. (2) Over sufficiently short periods of time (whose duration is related to the spread in momentum of the packet) the ... More
Noncommutative localization in algebraic $L$-theoryOct 15 2008Given a noncommutative (Cohn) localization $A \to \sigma^{-1}A$ which is injective and stably flat we obtain a lifting theorem for induced f.g. projective $\sigma^{-1}A$-module chain complexes and localization exact sequences in algebraic $L$-theory, ... More
Rogues' gallery: the full freedom of the Bianchi CMB anomaliesJan 15 2009May 11 2009Combining a recent derivation of the CMB evolution equations for homogeneous but anisotropic (Bianchi) cosmologies with an account of the full linearized dynamical freedoms available in such models, I calculate and discuss the various temperature and ... More
Constructing Smooth Loop SpacesDec 04 2006We consider the general problem of constructing the structure of a smooth manifold on a given space of loops in a smooth finite dimensional manifold. By generalising the standard construction for smooth loops, we derive a list of conditions for the model ... More
On determining absolute entropy without quantum theory or the Third Law of thermodynamicsOct 08 2015Jan 25 2016We employ classical thermodynamics to gain information about absolute entropy, without recourse to statistical methods, quantum mechanics or the Third Law of thermodynamics. The Gibbs-Duhem equation yields various simple methods to determine the absolute ... More
Self-force of a rigid ideal fluid, and a charged sphere in hyperbolic motionJul 22 2014We present two results in the treatment of self-force of accelerating bodies. If the total force on an extended rigid object is calculated from the change of momentum summed over planes of simultaneity of successive rest frames, then we show that an ideal ... More
Simple Quantum Error Correcting CodesMay 15 1996Methods of finding good quantum error correcting codes are discussed, and many example codes are presented. The recipe C_2^{\perp} \subseteq C_1, where C_1 and C_2 are classical codes, is used to obtain codes for up to 16 information qubits with correction ... More
Space, time, parallelism and noise requirements for reliable quantum computingAug 12 1997Quantum error correction methods use processing power to combat noise. The noise level which can be tolerated in a fault-tolerant method is therefore a function of the computational resources available, especially the size of computer and degree of parallelism. ... More