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Results for "John Ronayne"

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Attractor Behaviour in Multifield InflationApr 27 2018Jun 27 2018We study multifield inflation in scenarios where the fields are coupled non-minimally to gravity via $\xi_I(\phi^I)^n g^{\mu\nu}R_{\mu\nu}$, where $\xi_I$ are coupling constants, $\phi^I$ the fields driving inflation, $g_{\mu\nu}$ the space-time metric, ... More
Primordial fluctuations and non-Gaussianities in sidetracked inflationApr 30 2018Jul 27 2018Heavy scalar fields can undergo an instability during inflation as a result of their kinetic couplings with the inflaton. This is known as the geometrical destabilization of inflation, as it relies on the effect of the negative curvature of the field-space ... More
Investigating the Evolvability of Web Page Load TimeFeb 22 2018Client-side Javascript execution environments (browsers) allow anonymous functions and event-based programming concepts such as callbacks. We investigate whether a mutate-and-test approach can be used to optimise web page load time in these environments. ... More
Hyper non-Gaussianities in inflation with strongly non-geodesic motionFeb 08 2019Several recent proposals to embed inflation into high-energy physics rely on inflationary dynamics characterized by a strongly non-geodesic motion in negatively curved field space. This naturally leads to a transient instability of perturbations on sub-Hubble ... More
Infinitely many knots admitting the same integer surgeryJul 06 2014The construction of knots via annular twisting has been used to create families of knots yielding the same manifold via Dehn surgery. Prior examples have all involved Dehn surgery where the surgery slope is an integral multiple of 2. In this note we prove ... More
Vertex Ramsey problems in the hypercubeNov 01 2012If we 2-color the vertices of a large hypercube what monochromatic substructures are we guaranteed to find? Call a set S of vertices from Q_d, the d-dimensional hypercube, Ramsey if any 2-coloring of the vertices of Q_n, for n sufficiently large, contains ... More
Optimal Bacon-Shor codesSep 04 2012We study the performance of Bacon-Shor codes, quantum subsystem codes which are well suited for applications to fault-tolerant quantum memory because the error syndrome can be extracted by performing two-qubit measurements. Assuming independent noise, ... More
Saddlepoint approximations for likelihood ratio like statistics with applications to permutation testsMar 14 2012We obtain two theorems extending the use of a saddlepoint approximation to multiparameter problems for likelihood ratio-like statistics which allow their use in permutation and rank tests and could be used in bootstrap approximations. In the first, we ... More
Computing power series expansions of modular formsApr 30 2012Sep 30 2012We exhibit a method to numerically compute power series expansions of modular forms on a cocompact Fuchsian group, using the explicit computation a fundamental domain and linear algebra.
Video Chat with Multiple CamerasSep 06 2012The dominant paradigm for video chat employs a single camera at each end of the conversation, but some conversations can be greatly enhanced by using multiple cameras at one or both ends. This paper provides the first rigorous investigation of multi-camera ... More
Critical Data CompressionDec 23 2011A new approach to data compression is developed and applied to multimedia content. This method separates messages into components suitable for both lossless coding and 'lossy' or statistical coding techniques, compressing complex objects by separately ... More
A geometric answer to an open question of singular control with stoppingSep 28 2015We solve a problem of singular stochastic control with discretionary stopping, suggested as an interesting open problem by Karatzas, Ocone, Wang and Zervos (2000), by providing suitable candidates for the moving boundaries in an unsolved parameter range. ... More
Birth, Death and Flight: A Theory of Malthusian FlocksAug 22 2011Dec 11 2011I study "Malthusian Flocks": moving aggregates of self-propelled entities (e.g., organisms, cytoskeletal actin, microtubules in mitotic spindles) that reproduce and die. Long-ranged order (i.e., the existence of a non-zero average velocity $<\vec v (\vec ... More
The Fast Wandering of Slow BirdsSep 10 2009Oct 21 2011I study a single "slow" bird moving with a flock of birds of a different, and faster (or slower) species. I find that every "species" of flocker has a characteristic speed $\gamma\ne v_0$, where $v_0$ is the mean speed of the flock, such that, if the ... More
Leslie Hodson, particle physicist and pioneer in the study of cosmic rays 1925-2010; Obituary and bibliographyJun 02 2010Leslie Hodson was an experimental particle physicist who developed cloud and spark chamber techniques in the study of cosmic rays. This note reviews his career and provides a bibliography of his publications.
$L^2$-Cohomology of Geometrically Infinite Hyperbolic 3-ManifoldsDec 21 1995We give results on the following questions about a topologically tame hyperbolic 3-manifold M : 1. Does M have nonzero square-integrable harmonic 1-forms? 2. Does zero lie in the spectrum of the Laplacian acting on (1-forms on M)/Ker(d)?
On Macroscopic Complexity and Perceptual CodingMay 10 2010Jul 07 2011The theoretical limits of 'lossy' data compression algorithms are considered. The complexity of an object as seen by a macroscopic observer is the size of the perceptual code which discards all information that can be lost without altering the perception ... More
Rotation Numbers for $S^2$ diffeomorphismsDec 28 2014These largely expository notes describe the properties of the function ${\cal R}$ which assigns a number to a $4$-tuple of distinct fixed points of an orientation preserving homeomorphism or diffeomorphism of $S^2$.
Note on the construction of globular weak omega-groupoids from types, topological spaces etcFeb 25 2016A short introduction to Grothendieck weak omega-groupoids is given. Our aim is to give evidence that, in certain contexts, this simple language is a convenient one for constructing globular weak omega-groupoids. To this end, we give a short reworking ... More
Nonequilibrium Phenomena in Liquid CrystalsMay 21 1993This paper summarizes a talk presented at the April NATO ASI on Spatiotemporal Chaos in Complex Fluids, in Santa Fe, NM. The paper gives reasons that make complex fluids good material systems for conducting experiments on pattern formation and other nonequilibrium ... More
Kramers-Kronig, Bode, and the meaning of zeroJun 30 2011The implications of causality, as captured by the Kramers-Kronig relations between the real and imaginary parts of a linear response function, are familiar parts of the physics curriculum. In 1937, Bode derived a similar relation between the magnitude ... More
Outflows from Massive StarsDec 12 2007The properties of outflows powered by massive stars are reviewed with an emphasis on the nearest examples, Orion and Cepheus-A. The Orion OMC1 outflow may have been powered by the dynamical decay of a non-hierarchical massive star system that resulted ... More
Eclipsing Binary Stars: the Royal Road to Stellar AstrophysicsJan 06 2012Russell (1948) famously described eclipses as the "royal road" to stellar astrophysics. From photometric and spectroscopic observations it is possible to measure the masses and radii (to 1% or better!), and thus surface gravities and mean densities, of ... More
Quantum clock synchronization and quantum error correctionOct 29 2000I consider quantum protocols for clock synchronization, and investigate in particular whether entanglement distillation or quantum error-correcting codes can improve the robustness of these protocols. I also draw attention to some unanswered questions ... More
Fault-tolerant quantum computationDec 19 1997The discovery of quantum error correction has greatly improved the long-term prospects for quantum computing technology. Encoded quantum information can be protected from errors that arise due to uncontrolled interactions with the environment, or due ... More
Progress on Excited Hadrons in Lattice QCDDec 01 2011Dec 06 2011The study of excited hadron spectra using Lattice QCD is currently evolving. An important step toward obtaining resonance parameters from Lattice QCD is the calculation of finite volume energy spectra. Somewhat more rigorous studies of finite volume spectra ... More
Some new behaviour in the deformation theory of Kleinian groupsOct 16 2000We present examples of hyperbolizable 3-manifolds $M$ with the following property. Let $CC(\pi_1(M))$ denote the space of convex co-compact representations of $\pi_1(M)$. We show that for every $K\geq 1$ there exists a representation $\rho$ in $\bar {CC(\pi_1(M))}$ ... More
Quantum Quenches to a Critical Point in One Dimension: some further resultsJul 26 2015Jan 08 2016We describe several results concerning global quantum quenches from states with short-range correlations to quantum critical points whose low-energy properties are described by a 1+1-dimensional conformal field theory (CFT), extending the work of Calabrese ... More
Entanglement Entropy in Extended Quantum SystemsAug 22 2007After a brief introduction to the concept of entanglement in quantum systems, I apply these ideas to many-body systems and show that the von Neumann entropy is an effective way of characterising the entanglement between the degrees of freedom in different ... More
SLE(kappa,rho) and Conformal Field TheoryDec 10 2004Jan 13 2006SLE(kappa,rho) is a generalisation of Schramm-Loewner evolution which describes planar curves which are statistically self-similar but not conformally invariant in the strict sense. We show that, in the context of boundary conformal field theory, this ... More
Logarithmic Correlations in Quenched Random Magnets and PolymersNov 03 1999It is argued that logarithmic factors multiplying power law behavior are to be expected at or near non-mean field critical points of systems with short-range interactions described theoretically by any kind of n -> 0 limit, in which the effective free ... More
The Legacy of Ken WilsonAug 08 2013This is a brief account of the legacy of Ken Wilson in statistical physics, high energy physics, computing and education.
ADE and SLEOct 13 2006Nov 08 2006We point out that the probability law of a single domain wall separating clusters in ADE lattice models in a simply connected domain is identical to that of corresponding chordal curves in the lattice O(n) and Q-state Potts models, for suitable n or Q. ... More
Calogero-Sutherland model and bulk-boundary correlations in conformal field theoryOct 31 2003Jan 31 2004We show that, in any conformal field theory, the weights of all bulk primary fields that couple to N phi_{2,1} fields on the boundary are given by the spectrum of an N-particle Calogero-Sutherland model. The corresponding correlation function is simply ... More
Stochastic Loewner Evolution and Dyson's Circular EnsemblesJan 28 2003Nov 11 2003Stochastic Loewner Evolution (SLE_kappa) has been introduced as a description of the continuum limit of cluster boundaries in two-dimensional critical systems. We show that the problem of N radial SLEs in the unit disc is equivalent to Dyson's Brownian ... More
Renormalisation group approach to reaction-diffusion problemsJul 23 1996Sep 11 1996This is the text of a talk given at the conference in memory of Claude Itzykson at Saclay in June 1996. It contains an introductory survey and an account of recent developments in the field theoretic RG approach to reaction-diffusion problems.
Continuously Varying Exponents for Oriented Self-Avoiding WalksDec 07 1993A two-dimensional conformal field theory with a conserved $U(1)$ current $\vec J$, when perturbed by the operator ${\vec J}^{\,2}$, exhibits a line of fixed points along which the scaling dimensions of the operators with non-zero $U(1)$ charge vary continuously. ... More
An unavoidable set of D-reducible configurationsMay 01 2009May 04 2009We give a new proof of the four-color theorem by exhibiting an unavoidable set of 2822 D-reducible configurations. The existence of such a set had been conjectured by several researchers including Stromquist, Appel and Haken, and Robertson, Sanders, Seymour ... More
Millisecond Pulsar Searches and Double Neutron Star BinariesMay 04 2004May 06 2004A unified strategy is developed that can be used to search for millisecond pulsars (MSPs) with ~solar mass companions (including neutron star companions in double neutron star binaries [DNSBs]) belonging to both very short period binaries, and those with ... More
The SN 1987A Link to Others and Gamma-Ray BurstsAug 16 2007Feb 06 2008Early measurements of SN 1987A can be interpreted in light of a beam/jet (BJ), with a collimation factor >10,000, which impacted polar ejecta (PE) to produce the "Mystery Spot" (MS), ~24 lt-d away. Other details of SN 1987A suggest that it came from a ... More
Does merger-induced core-collapse produce gamma-ray bursts in type Ib & Ic supernovae?Oct 23 2003Nov 12 2003Gamma-ray bursts, discovered over three decades ago, can appear to be a hundred times as luminous as the brightest supernovae. However, there has been evidence for some time now of an association of gamma-ray bursts with supernovae of type Ib and Ic. ... More
What is superresolution microscopy?May 06 2014Oct 08 2014I explain what is, what is not, and what is only sort of superresolution microscopy. I discuss optical resolution, first in terms of diffraction theory, then in terms of linear systems theory, and finally in terms of techniques that use prior information, ... More
Generalized measurements by linear elementsAug 23 2001I give a first characterization of the class of generalized measurements that can be exactly realized on a pair of qudits encoded in indistinguishable particles, by using only linear elements and particle detectors. Two immediate results follow from this ... More
An Introduction To Solar Neutrino ResearchNov 18 1997The first lecture describes the conflicts between the combined standard model (minimal electroweak and solar) predictions and the results of solar neutrino experiments. The second lecture discusses the possibilities for detecting with solar neutrinos ... More
Structure, Individuality and Quantum GravityJul 18 2005Jul 19 2005After reviewing various interpretations of structural realism, I adopt here a definition that allows both relations between things that are already individuated (which I call ``relations between things'') and relations that individuate previously un-individuated ... More
Elliptical Galaxies and Bulges of Disk Galaxies: Summary of Progress and Outstanding IssuesApr 13 2015This is the summary chapter of a review book on galaxy bulges. Bulge properties and formation histories are more varied than those of ellipticals. I emphasize two advances: 1 - "Classical bulges" are observationally indistinguishable from ellipticals, ... More
Supermassive Black Holes in Disk GalaxiesJul 26 2000Dynamical searches find central dark objects - candidate supermassive black holes (BHs) - in at least 34 galaxies. The demographics of these objects lead to the following conclusions: (1) BH mass correlates with the luminosity of the bulge component of ... More
A Parallel Tree CodeMar 18 1996We describe a new implementation of a parallel N-body tree code. The code is load-balanced using the method of orthogonal recursive bisection to subdivide the N-body system into independent rectangular volumes each of which is mapped to a processor on ... More
Deleting Powers in WordsAug 30 2016We consider the language consisting of all words such that it is possible to obtain the empty word by iteratively deleting powers. It turns out that in the case of deleting squares in binary words this language is regular, and in the case of deleting ... More
ET Probes: Looking Here as Well as ThereAug 05 2016Almost all SETI searches to date have explicitly targeted stars in the hope of detecting artificial radio or optical transmissions. It is argued that extra-terrestrials (ET) might regard sending physical probes to our own Solar System as a more efficient ... More
String Theory on AdS_3/Z_NJul 15 2001We study string theory on singular Z_N quotients of AdS_3, corresponding to spaces with conical defects. The spectrum is computed using the orbifold procedure. It is shown that spectral flow may be used to generate the twisted sectors. We further compute ... More
Non-Markovian Quantum Feedback Networks I: Quantum Transmission Lines, Lossless Bounded Real Property and Limit Markovian ChannelsApr 08 2016The purpose of this paper is to set out the problems of modeling quantum communication and signal processing where the communication between systems via a non-Markovian channel. This is a general feature of quantum transmission lines. Our ultimate objective ... More
Feynman Diagrams and the Quantum Stochastic CalculusNov 09 2004We present quantum stochastic calculus in terms of diagrams taking weights in the algebra of observables of some quantum system. In particular, we note the absence of non-time-consecutive Goldstien diagrams. We review recent results in Markovian limits ... More
Boson-Fermion unification implemented by Wick calculusSep 10 2003Jan 15 2004We construct a transformation between Bose Fock space and Fermi Fock space that is super-symmetric in the sense that it converts Boson fields into Fermi fields over a fixed one-particle space. The transformation involves the spectral splitting of the ... More
Holevo-ordering and the continuous-time limit for open Floquet dynamicsNov 21 2003We consider an atomic beam reservoir as a source of quantum noise. The atoms are modelled as two-state systems and interact one-at-a-time with the system. The Floquet operators are described in terms of the Fermionic creation, annihilation and number ... More
Q-ball Evolution, B-ball Baryogenesis and the f_{B} ProblemDec 29 2000Feb 22 2001We consider some of the issues surrounding the formation and evolution of Q-balls in the MSSM and its extensions. The ratio of the baryon number packed into Q-balls to that outside, f_{B}, plays a fundamental role in determining the relationship of dark ... More
Signatures of Planck Corrections in a Spiralling Axion Inflation ModelDec 22 2014May 04 2015The minimal sub-Planckian axion inflation model accounts for a large scalar-to-tensor ratio via a spiralling trajectory in the field space of a complex field $\Phi$. Here we consider how the predictions of the model are modified by Planck scale-suppressed ... More
Simultaneous Generation of WIMP Miracle-like Densities of Baryons and Dark MatterAug 23 2011Mar 05 2015The observed density of dark matter is of the magnitude expected for a thermal relic weakly-interacting massive particle (WIMP). In addition, the observed baryon density is within an order of magnitude of the dark matter density. This suggests that the ... More
Unparticles: Interpretation and CosmologyMay 13 2008May 14 2008We discuss the physical interpretation of unparticles and review the constraints from cosmology. Unparticles may be understood in terms of confined states of a strongly-coupled scale-invariant theory, where scale-invariance implies that the confined states ... More
Positive Order H^2 Mass Corrections and Affleck-Dine BaryogenesisFeb 21 1999Mar 03 1999It is usually assumed that the order H^2 corrections to the SUSY-breaking mass squared terms in the early Universe must be negative in order to allow the Affleck-Dine mechanism to work. We reconsider this assumption in the context of D-term inflation ... More
Physics Beyond the Standard ModelJan 15 2000I briefly summarize the prospects for extending our understanding of physics beyond the standard model within the next five years.
Bayes versus the virial theorem: inferring the potential of a galaxy from a kinematical snapshotMar 25 2013Oct 21 2013We present a new framework for estimating a galaxy's gravitational potential, Phi(x), from its stellar kinematics by adopting a fully non-parametric model for the galaxy's unknown action-space distribution function, f(J). Having an expression for the ... More
Category $\mathcal{J}$ Modules for Hamiltonian Vector Fields on a TorusOct 29 2016Modules for the Lie algebra of Hamiltonian vector fields on a torus, which admit a compatible action for the commutative algebra of multivariate Laurent polynomials are called category $\mathcal{J}$. This paper classifies the indecomposable and the irreducible ... More
Study of the Decays KL -> pi+ pi- gamma and KL -> pi+ pi- e+ e- at KTeVMar 15 1999We present new results on the related rare KL decay modes KL -> pi+ pi- gamma and KL -> pi+ pi- e+ e-. KTeV has performed the first direct measurement of the form factor for the "direct emission" component of KL -> pi+ pi- gamma decays, a quantity with ... More
Specht modules and semisimplicity criteria for Brauer and Birman--Murakami--Wenzl AlgebrasMay 29 2007A construction of bases for cell modules of the Birman--Murakami--Wenzl (or B--M--W) algebra $B_n(q,r)$ by lifting bases for cell modules of $B_{n-1}(q,r)$ is given. By iterating this procedure, we produce cellular bases for B--M--W algebras on which ... More
Generalized Gaugino Condensation in Super Yang-Mills Theories: Discrete R-Symmetries and VacuaMay 25 2010One can define generalized models of gaugino condensation as theories which dynamically break a discrete R-symmetry, but do not break supersymmetry. We consider general examples consisting of gauge and matter fields, and the minimal number of gauge singlet ... More
`t Hooft Anomaly Matching for QCDJun 10 1997Mar 03 1998I present a set of theories which display non-trivial `t Hooft anomaly matching for QCD with $F$ flavors. The matching theories are non-Abelian gauge theories with "dual" quarks and baryons, rather than the purely confining theories of baryons that `t ... More
Naturally Light ScalarsOct 04 1995I argue that in certain chiral gauge theories composite scalars associated with chiral symmetry breaking can be light (i.e. lighter than naive scaling from QCD would suggest) without any fine-tuning. These scalars will be even lighter in chiral gauge ... More
The Multichannel Quark ModelJun 19 1996We discuss the non-relativistic multichannel quark model and describe the techniques developed to solve the resulting equations. We then investigate some simple solutions to demonstrate how the model unifies meson-meson scattering with meson spectroscopy, ... More
Fields of Rationality of Cusp FormsFeb 03 2015Dec 09 2015In this paper, we prove that for any totally real field $F$, weight $k$, and nebentypus character $\chi$, the proportion of Hilbert cusp forms over $F$ of weight $k$ and character $\chi$ with bounded field of rationality approaches zero as the level grows ... More
Limit on an Isotropic Diffuse Gamma-Ray Population with HAWCAug 17 2015Data from 105 days from the High Altitude Water Cherenkov Observatory (HAWC) have been used to place a new limit on an isotropic diffuse gamma-ray population above 10 TeV. High- energy isotropic diffuse gamma-ray emission is produced by unresolved extragalactic ... More
Ising Model Scaling Functions at Short DistanceJul 06 2001A method for proving the Luther-Peschel formula for the short distance asymptotics of the Ising model scaling functions is sketched.
Deformation analysis of matrix modelsMar 03 1994The Tracy-Widom equations associated with level spacing distributions are realized as a special case of monodromy preserving deformations.
Generalized LR parsing and the shuffle operatorNov 17 2016We adapt Tomita's Generalized LR algorithm to languages generated by context-free grammars enriched with a shuffle operator. The change involves extensions to the underlying handle-finding finite automaton, construction of parser tables, and the necessary ... More
Recent Results in Search for New Physics at the Tevatron (Run 1)May 29 2002We present some new results on searches for new physics at the Tevatron Run 1 (1992 -- 1996). The topics covered are searches for R-Parity violating and conserving mSUGRA, large extra dimensions in di-photon and monojet channels, leptoquark in jets + ... More
Cauchy kernels for some conformally flat manifoldsMar 26 2003Here we will consider examples of conformally flat manifolds that are conformally equivalent to open subsets of the n-dimensional sphere. For such manifolds we shall introduce a Cauchy kernel and Cauchy integral formula for sections tasking values in ... More
Entropy and Area in Loop Quantum GravityMay 22 2005Oct 30 2005Black hole thermodynamics suggests that the maximum entropy that can be contained in a region of space is proportional to the area enclosing it rather than its volume. I argue that this follows naturally from loop quantum gravity and a result of Kolmogorov ... More
The Pauli Exclusion Principle and SU(2) Versus SO(3) in Loop Quantum GravityJan 29 2004Recent attempts to resolve the ambiguity in the loop quantum gravity description of the quantization of area has led to the idea that $j=1$ edges of spin-networks dominate in their contribution to black hole areas as opposed to $j=1/2$ which would naively ... More
The Pauli Exclusion Principle and SU(2) vs. SO(3) in Loop Quantum GravityMay 19 2003Recent attempts to resolve the ambiguity in the loop quantum gravity description of the quantization of area has led to the idea that j=1 edges of spin-networks dominate in their contribution to black hole areas as opposed to j=1/2 which would naively ... More
On the limiting procedure by which $SDiff(T^2)$ and $SU(\infty)$ are associatedMay 01 2004There have been various attempts to identify groups of area-preserving diffeomorphisms of 2-dimensional manifolds with limits of SU(N) as $N\to\infty$. We discuss the particularly simple case where the manifold concerned is the two-dimensional torus $T^2$ ... More
The SSM with Suppressed SUSY ChargeApr 21 2016May 18 2016An earlier paper showed that it is possible to write down new SUSY Actions in which it is not possible to define a Supersymmetry Charge. SUSY is defined in these new Actions by the fact that they satisfy Master Equations. The new SUSY Actions are very ... More
Detailed Calculations of the Mass Spectrum for the Leptons after Supersymmetry Breaking in the Supersymmetric Standard Model: Cybersusy IVAug 17 2008This is the fourth of a series of four papers introducing cybersusy, which is a new approach to supersymmetry breaking in the supersymmetric standard model. This paper contains a brief summary, and then goes on to the calculation of the propagators and ... More
Supersymmetry Anomalies, the Witten Index and the Standard ModelNov 17 1993The supersymmetric standard model (SSM) contains a wealth of potential supersymmetry anomalies, all of which occur in the renormalization of composite operators of the theory. The coefficients of the weak-E.M. superanomalies should be related to the Witten ... More
Some Composite Hadrons and Leptons which induce Supersymmetry Breaking in the Supersymmetric Standard Model: Cybersusy IIIAug 16 2008This is the third paper in a series of four papers which introduce cybersusy, which is a new mechanism for supersymmetry breaking in the supersymmetric standard model (SSM). In this paper we display some solutions to the constraint equations of BRS cohomology ... More
Short-range correlations and their implications for isospin-dependent modification of nuclear quark distributionsAug 20 2015The past decade has provided a much clearer picture of the structure of high-momentum components in nucleons, associated with hard, short-distance interactions between pairs of nucleons. Recent Jefferson Lab data on light nuclei suggest a connection between ... More
Hadrons in the Nuclear Medium -- Quarks, Nucleons, or a Bit of Both?Feb 06 2006Quantum Chromodynamics (QCD) is the theory governing the strong interaction of particles. It describes the interactions that bind quarks and gluons into protons and neutrons, and binds these into nuclei. We believe QCD to be as fundamental and complete ... More
Discrete Glimpses of the Physics Landscape after the Higgs DiscoveryJan 22 2015What is the Higgs boson telling us? What else is there? How do we find it? This talk discusses these current topics in particle physics in the wake of the Higgs discovery, with particular emphasis on the discrete symmetries CP and R-parity, not forgetting ... More
Summary of the Nobel Symposium on LHC ResultsSep 13 2013This is a personal summary of points made during, and arising from the symposium, drawing largely from the talks presented there. The Standard Model is doing fine, including QCD, the electroweak sector and flavour physics. The good news is that a Standard-Model-like ... More
Prospects for Discovering Supersymmetry at the LHCOct 07 2008Supersymmetry is one of the best-motivated candidates for physics beyond the Standard Model that might be discovered at the LHC. There are many reasons to expect that it may appear at the TeV scale, in particular because it provides a natural cold dark ... More
Beyond the Standard Model at the LHC and BeyondOct 03 2007Many of the open questions beyond the Standard Model will be addressed by the LHC, including the origin of mass, supersymmetry, dark matter and the possibility of large extra dimensions. A linear e+ e- collider (LC) with sufficient centre-of-mass energy ... More
What Next in Flavour Physics and CP Violation?Nov 20 2002The future of flavour physics and CP violation in the quark, lepton and Higgs sectors are discussed, particularly from the viewpoint of physics beyond the Standard Model, such as supersymmetry. Current issues in B to pi^+ pi^-, phi K_s and D^*+ D^*-, ... More
Summary of DIS 98Jun 29 1998A personal selection is made of some of the hot topics debated at this conference, including examples of using our knowledge of QCD to make electroweak measurements, structure functions at low x in the light of the corrections to the leading BFKL behaviour ... More
Supersymmetric Fits after the Higgs Discovery and Implications for Model BuildingDec 19 2013The data from the first run of the LHC at 7 and 8 TeV, together with the information provided by other experiments such as precision electroweak measurements, flavour measurements, the cosmological density of cold dark matter and the direct search for ... More
Casting Light on Dark MatterJun 15 2011The prospects for detecting a candidate supersymmetric dark matter particle at the LHC are reviewed, and compared with the prospects for direct and indirect searches for astrophysical dark matter. The discussion is based on a frequentist analysis of the ... More
Prospects for New Physics at the LHCApr 05 2010High-energy collisions at the LHC are now starting. The new physics agenda of the LHC is reviewed, with emphasis on the hunt for the Higgs boson (or whatever replaces it) and supersymmetry. In particular, the prospects for discovering new physics in the ... More
Future Perspectives at CERNJun 04 2002Current and future experiments at CERN are reviewed,with emphasis on those relevant to astrophysics and cosmology. These include experiments related to nuclear astrophysics, matter-antimatter asymmetry, dark matter, axions, gravitational waves, cosmic ... More
CERN as a Non-School Resource for Science EducationMay 09 2000As a large international research laboratory, CERN feels it has a special responsibility for outreach, and has many activities directed towards schools, including organized visits, an on-site museum, hands-on experiments, a Summer intern programme for ... More
Heavy-Ion Collisions and Black Holes in Anti-de-Sitter SpaceFeb 23 1999Recent developments linking non-perturbative quantum gauge theories in Minkowski space to classical gravity theories in anti-de-Sitter space are reviewed at a simple level. It is suggested how these spectacular advances may be extended to discuss the ... More
A pathology of asymptotic multiplicity in the relative settingFeb 10 2015We point out an example of a projective family $\pi : X \to S$, a $\pi$-pseudoeffective divisor $D$ on $X$, and a subvariety $V \subset X$ for which the asymptotic multiplicity $\sigma_V(D;X/S)$ is infinite. This shows that the divisorial Zariski decomposition ... More
Derived-equivalent rational threefoldsOct 31 2013We describe an infinite set of smooth projective threefolds that have equivalent derived categories but are not isomorphic, contrary to a conjecture of Kawamata. These arise as blow-ups of $\mathbb P^3$ at various configurations of 8 points, which are ... More