Results for "Nicole Hiller"

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Adaptive and Safe Bayesian Optimization in High Dimensions via One-Dimensional SubspacesFeb 08 2019Bayesian optimization is known to be difficult to scale to high dimensions, because the acquisition step requires solving a non-convex optimization problem in the same search space. In order to scale the method and keep its benefits, we propose an algorithm ... More
First hint of non-standard CP violation from B --> Phi K_S decayJul 30 2002Oct 10 2002We comment on the implications of the recently measured CP asymmetry in B --> Phi K_S decay. The data disfavor the Standard Model at 2.7 sigma and -if the trend persists in the future with higher statistics - require the existence of CP violation beyond ... More
$b \to s \ell^+ \ell^-$ decays in and beyond the Standard ModelAug 09 2000We briefly review the status of rare radiative and semileptonic $b \to s (\gamma, \ell^+ \ell^-)$, ($\ell=e,\mu$) decays. We discuss possible signatures of new physics in these modes and emphazise the role of the exclusive channels. In particular, measurements ... More
B -> K(*) l+ l- @ Low Recoil and Physics ImplicationsMay 28 2013This talk covers recent theoretical progress in exclusive semileptonic rare B-decays at low hadronic recoil. The efficient parametric suppression of the 1/mb corrections in this region provides opportunities to probe the Standard Model and beyond at precision ... More
Flavor violation in SUSYMay 04 2009I review recent opportunities from flavor for b-physics and collider searches.
b-physics signals of the lightest CP-odd Higgs in the NMSSM at large tan betaApr 24 2004Jun 17 2004We investigate the low energy phenomenology of the lighter pseudoscalar $A_1^0$ in the NMSSM. The $A_1^0$ mass can naturally be small due to a global $U(1)_R$ symmetry of the Higgs potential, which is only broken by trilinear soft terms. The $A_1^0$ mass ... More
The Pheno-analysis of B-> K(*) mu^+ mu^- decays in 2011 plusJun 08 2011We report on recent developments in the phenomenology of exclusive b -> s mu^+ mu^- decays in testing the standard model and explore its borders: the benefits of the region of large dimuon invariant masses and the exploitation of the angular distributions. ... More
Improved QCD perturbative contributions and power corrections in radiative and semileptonic rare B decaysSep 23 1998We calculate the leading power corrections to the decay rates, distributions and hadronic spectral moments in rare inclusive \bxsll decays in the standard model, using heavy quark expansion (HQE) in $(1/m_b)$ and a phenomenological model implementing ... More
Testing factorizationNov 19 2001We briefly review the status of factorization in $b$-decays. We discuss several experimental tests of its nature and stress their importance. We show that decays into mesons which have small decay constants or spin greater than one (`designer mesons') ... More
$B \to K^* \ell \ell$ Standard Model contributions -- Zooming in on high $q^2$Jun 05 2016To further precision studies with $B \to K^{(*)} \ell \ell$ decays in the high-$q^2$ window uncertainties related to the operator product expansion (OPE) need to be scrutinized. How well can the OPE describe $B \to K^* (\to K \pi) \ell \ell$ angular distributions ... More
Physics reach of rare b-decaysJul 09 2002I discuss the theoretical and empirical status of $b \to s \gamma$, $b \to s \ell^+ \ell^-$ decays, as well as their future prospects. I emphasize those observables in rare $b$-decays which can potentially establish new physics and distinguish between ... More
Phenomenology of New PhysicsAug 18 2003Sep 10 2003I review the phenomenology of new physics in low energy processes using the notion of minimal flavor violation (vs. non-minimal flavor violation). I compare the predictions of beyond-the-standard models and show that among certain observables in rare ... More
Probing for New Physics in Polarized $Λ_b$ decays at the ZAug 08 2001Jan 29 2002Polarized $\Lambda_b \to \Lambda \gamma$ decays at the Z pole are shown to be well suited for probing a large variety of New Physics effects. A new observable is proposed, the angular asymmetry between the $\Lambda_b$ spin and photon momentum, which is ... More
Light-front holography and the light-front coupled-cluster methodFeb 02 2014We summarize the light-front coupled-cluster (LFCC) method for the solution of field-theoretic bound-state eigenvalue problems and indicate the connection with light-front holographic QCD. This includes a sample application of the LFCC method and leads ... More
Pauli-Villars regularization of non-Abelian gauge theoriesDec 29 2015As an extension of earlier work on QED, we construct a BRST-invariant Lagrangian for SU(N) Yang-Mills theory with fundamental matter, regulated by the inclusion of massive Pauli-Villars (PV) gluons and PV quarks. The underlying gauge symmetry for massless ... More
Pauli-Villars regularization of field theories on the light frontSep 30 2010Four-dimensional quantum field theories generally require regularization to be well defined. This can be done in various ways, but here we focus on Pauli--Villars (PV) regularization and apply it to nonperturbative calculations of bound states. The philosophy ... More
Nonperturbative solution of Yukawa theory and gauge theoriesSep 28 2004Recent progress in the nonperturbative solution of (3+1)-dimensional Yukawa theory and quantum electrodynamics and (1+1)-dimensional super Yang--Mills theory is summarized.
Nonperturbative solution of supersymmetric gauge theoriesJul 12 2002Recent work on the numerical solution of supersymmetric gauge theories is described. The method used is SDLCQ (supersymmetric discrete light-cone quantization). An application to N=1 supersymmetric Yang-Mills theory in 2+1 dimensions at large N_c is summarized. ... More
Pauli-Villars regularization in DLCQAug 13 1999Calculations in a (3+1)-dimensional model indicate that Pauli-Villars regularization can be combined with discrete light-cone quantization (DLCQ) to solve at least some field theories nonperturbatively. Discrete momentum states of Pauli-Villars particles ... More
$R_K$ and future $b \to s \ell \ell$ BSM opportunitiesAug 07 2014Flavor changing neutral current $|\Delta B|=|\Delta S|=1$ processes are sensitive to possible new physics at the electroweak scale and beyond, providing detailed information about flavor, chirality and Lorentz structure. Recently the LHCb collaboration ... More
More Model-Independent Analysis of b->s ProcessesOct 17 2003Jan 09 2004We study model-independently the implications of non-standard scalar and pseudoscalar interactions for the decays b ->s gamma, b -> s g, b -> s l^+l^- (l=e,mu) and B_s -> mu^+ mu^-. We find sizeable renormalization effects from scalar and pseudoscalar ... More
Flavorful hybrid anomaly-gravity mediationJan 27 2011May 26 2011We consider supersymmetric models where anomaly and gravity mediation give comparable contributions to the soft terms and discuss how this can be realized in a five-dimensional brane world. The gaugino mass pattern of anomaly mediation is preserved in ... More
Dynamic Simulation of Soft Heterogeneous ObjectsDec 12 2012This paper describes a 2D and 3D simulation engine that quantitatively models the statics, dynamics, and non-linear deformation of heterogeneous soft bodies in a computationally efficient manner. There is a large body of work simulating compliant mechanisms. ... More
A nonperturbative coupled-cluster method for quantum field theoriesAug 31 2012The nonperturbative Hamiltonian eigenvalue problem for bound states of a quantum field theory is formulated in terms of Dirac's light-front coordinates and then approximated by the exponential-operator technique of the many-body coupled-cluster method. ... More
A nonperturbative light-front coupled-cluster methodAug 30 2012The nonperturbative Hamiltonian eigenvalue problem for bound states of a quantum field theory is formulated in terms of Dirac's light-front coordinates and then approximated by the exponential-operator technique of the many-body coupled-cluster method. ... More
Supersymmetric Two-Dimensional QCD at Finite TemperatureAug 04 2006Light-cone coordinates and supersymmetric discrete light-cone quantization are used to analyze the thermodynamics of two-dimensional supersymmetric quantum chromodynamics with a Chern-Simons term in the large-N_c approximation. This requires estimation ... More
Calculations with DLCQJul 26 2000The method of discrete light-cone quantization (DLCQ) and useful refinements are summarized. Applications to various field theories are reviewed.
Pauli-Villars regularization and discrete light-cone quantization in Yukawa theoryFeb 21 2000The techniques of Pauli-Villars regularization and discrete light-cone quantization are combined to analyze Yukawa theory in a single-fermion truncation. A special form of the Lanczos algorithm is constructed for diagonalization of the indefinite-metric ... More
Nonperturbative solution of Yukawa theory and gauge theoriesJul 20 2004Recent progress in the nonperturbative solution of (3+1)-dimensional Yukawa theory and quantum electrodynamics (QED) and (1+1)-dimensional super Yang-Mills (SYM) theory will be summarized. The work on Yukawa theory has been extended to include two-boson ... More
Nonperturbative light-front methodsOct 10 2003Two methods for the nonperturbative solution of field-theoretic bound-state problems, based on light-front coordinates, are briefly reviewed. One uses Pauli-Villars regularization and the other supersymmetry. Applications to Yukawa theory and super Yang-Mills ... More
Methods for the nonperturbative approximation of form factors and scattering amplitudesJul 26 2000Methods are described for the nonperturbative calculation of wave functions and scattering amplitudes in light-cone quantization. Form factors are computed from the boost-invariant wave functions, which appear as coefficients in a Fock-state expansion ... More
The CP-conserving contribution to the transverse muon polarization in K+ -> mu+ nu gammaMar 08 1999We present a detailed estimate of the transverse muon polarization (P_T) due to electromagnetic final-state interactions in the decay $K^+ \to \mu^+ \nu \gamma$. This CP-conserving effect represents the dominant contribution to P_T within the Standard ... More
A Theoretical Reappraisal of Branching Ratios and CP Asymmetries in the Decays $B \to (X_d,X_s) \ell^+ \ell^-$ and Determination of the CKM ParametersDec 07 1998We present a theoretical reappraisal of the branching ratios and CP asymmetries for the decays $ B \to X_q \ell^+ \ell^-$, with $q=d,s$, taking into account current theoretical uncertainties in the description of the inclusive decay amplitudes from the ... More
Pauli-Villars Regularization in a Discrete Light-Cone ModelJul 03 1998Pauli-Villars regularization is successfully applied to nonperturbative calculations in a (3+1)-dimensional light-cone model. Numerical results obtained with discretized light-cone quantization compare favorably with the analytic solution.
A light-front coupled-cluster method for quantum field theoriesJun 26 2012The Hamiltonian eigenvalue problem for bound states of a quantum field theory is formulated in terms of Dirac's light-front coordinates and then approximated by the exponential-operator technique of the standard coupled-cluster method. This approximation ... More
Wave functions and spectra from (S)DLCQNov 09 2001Applications of discretized light-cone quantization (DLCQ) to (3+1)-dimensional Yukawa theory with Pauli-Villars regulators and of supersymmetric DLCQ (SDLCQ) to (2+1)-dimensional super Yang-Mills theory are discussed. The ability of these methods to ... More
Solving the strong CP problem with supersymmetryMay 24 2001Jun 24 2001We propose a new solution to the strong CP problem based on supersymmetric non-renormalization theorems. CP is broken spontaneously and it's breaking is communicated to the MSSM by radiative corrections. The strong CP phase is protected by a susy non-renormalization ... More
Collective modes and current-algebraic sum rules in nuclear mediumJul 31 1998In-medium sum rules following from the chiral charge algebra of QCD are reviewed, and new sum rules are derived. The new sum rules relate the I^G(J^{PC})=1^-(0^{++}) excitations (quantum numbers of a_0(980)) to the scalar and isovector densities, and ... More
New ways to explore factorization in b decaysMay 18 2001Jul 09 2001We propose to study factorization breaking effects in exclusive b decays where they are strongly enhanced over the factorizing contributions. This can be done by selecting final-state mesons with a small decay constant or with spin greater than one. We ... More
Application of Discrete Light-Cone Quantization to Yukawa Theory in Four DimensionsOct 06 2000The numerical technique of discrete light-cone quantization (DLCQ) is applied to a single-fermion truncation of Yukawa theory in four dimensions. The truncated theory is regulated by three Pauli-Villars bosons, which are introduced directly in the DLCQ ... More
Nonperturbative light-front Hamiltonian methodsJun 27 2016We examine the current state-of-the-art in nonperturbative calculations done with Hamiltonians constructed in light-front quantization of various field theories. The language of light-front quantization is introduced, and important (numerical) techniques, ... More
Solution of the one-dimensional Dirac equation with a linear scalar potentialNov 01 2001We solve the Dirac equation in one space dimension for the case of a linear, Lorentz-scalar potential. This extends earlier work of Bhalerao and Ram [Am. J. Phys. 69 (7), 817-818 (2001)] by eliminating unnecessary constraints. The spectrum is shown to ... More
Nonperturbative Calculation of Scattering AmplitudesJul 20 2000A method for the nonperturbative calculation of scattering amplitudes and cross sections is discussed in the context of light-cone quantization. The Lanczos-based recursion method of Haydock is suggested for the computation of matrix elements of the resolvent ... More
Diagnosing lepton-nonuniversality in $b \to s \ell \ell$Nov 18 2014Feb 08 2015Ratios of branching fractions of semileptonic B decays, $(B \to H \mu \mu)$ over $(B \to H ee)$ with $H=K, K^*,X_s, K_0(1430), \phi, \ldots$ are sensitive probes of lepton universality. In the Standard Model, the underlying flavor changing neutral current ... More
Extracting $B \to K^*$ Form Factors from DataApr 19 2012We extract ratios of $B \to K^*$ form factors at low hadronic recoil from recent data on $B \to K^* \mu^+ \mu^-$ decays in a model-independent way. The presented method will improve in the future with further (angular) studies in semileptonic rare B-decays ... More
Semileptonic Form-factors from B-> K* gamma Decays in the Large Energy LimitNov 21 2000Making use of the measurement of the $B\to K^*\gamma$ branching ratio together with the relations following from the limit of high recoil energy, we obtain stringent constraints on the values of the form-factors entering in heavy-to-light $B\to V\ell\ell'$ ... More
Implications of Non-Standard CP Violation in Hadronic $B$-DecaysJul 21 2003Jul 29 2004We investigate a class of models for new physics which could produce a large difference in sin 2 beta between B0-> J/\psi K(S) and the ``pure penguin'' mode B0-> phi K(S). In such models, the dominant effect is through a Z-penguin and therefore a pattern ... More
Yet another way to measure $γ$May 21 2001Sep 17 2001We show that the CKM phase $2 \beta+\gamma$ can be extracted from measurement of the time dependent rates in the decays $\bar{B}^0 \to D^{(*)\pm} M^\mp$ and $B^0 \to D^{(*)\pm} M^\mp$, where $M=a_0$, $\pi(1300)$, $b_1$, $a_2$, $\pi_2$, $\rho_3$. These ... More
The Casimir effect in light-front quantizationOct 02 2014We show that the standard result for the Casimir force between conducting plates at rest in an inertial frame can be computed in light-front quantization. This is not the same as light-front analyses where the plates are at "rest" in an infinite momentum ... More
Numerical evidence for the Maldacena conjecture in two-dimensional N=(8,8) super Yang-Mills theorySep 09 2005The N=(8,8) super Yang-Mills theory in 1+1 dimensions is solved at strong coupling to directly confirm the predictions of supergravity at weak coupling. The calculations are done in the large-N_c approximation using Supersymmetric Discrete Light-Cone ... More
On the Use of Discrete Light-Cone Quantization to Compute Form FactorsSep 22 1999Techniques for the field-theoretic calculation of a form factor are described and applied to a dressed-fermion state of a (3+1)-dimensional model Hamiltonian. Discrete light-cone quantization plays the crucial role as the means by which Fock-state wave ... More
Nonperturbative Renormalization in Light-Cone QuantizationMar 28 1997Two approaches to nonperturbative renormalization are discussed for theories quantized on the light cone. One is tailored specifically to a calculation of the dressed-electron state in quantum electrodynamics, where an invariant-mass cutoff is used as ... More
(A)symmetries of weak decays at and near the kinematic endpointDec 06 2013Mar 05 2014At the kinematic endpoint of zero recoil physical momenta are parallel which leads to symmetries in the decay distributions. We implement this observation for decays of the type $A \to (B_1 B_2) C$ by extending the helicity formalism to include an unphysical ... More
Strong-weak CP hierarchy from non-renormalization theoremsJan 27 2002We point out that the hierarchy between the measured values of the CKM phase and the strong CP phase has a natural origin in supersymmetry with spontaneous CP violation and low energy supersymmetry breaking. The underlying reason is simple and elegant: ... More
Current algebra and soft pionic modes in asymmetric quark matterSep 24 1996Nov 27 1996Pionic excitations are analyzed in isospin-asymmetric Fermi gas of constituent quarks. It is found that in addition to the usual pionic excitations, there exists a very low collective mode with quantum numbers of the charged pion (spin-isospin sound). ... More
On the Peaking Phenomenon of the Lasso in Model SelectionApr 28 2009I briefly report on some unexpected results that I obtained when optimizing the model parameters of the Lasso. In simulations with varying observations-to-variables ratio n=p, I typically observe a strong peak in the test error curve at the transition ... More
Four-Dimensional Algebraic ToriNov 01 2015Nov 03 2015The study of the birational properties of algebraic $k$ tori began in the sixties and seventies with work of Voskresenkii, Endo, Miyata, Colliot-Thelene and Sansuc. There was particular interest in determining the rationality of a given algebraic $k$ ... More
An Ehrenfeucht-Fraisse Game Approach to Collapse Results in Database TheoryDec 20 2002We present a new Ehrenfeucht-Fraisse game approach to collapse results in database theory and we show that, in principle, this approach suffices to prove every natural generic collapse result. Following this approach we can deal with certain infinite ... More
Sur les espaces de modules des fibres vectoriels de rang deux sur des hypersurfaces de P^3Jan 08 1996Mar 15 1996Soit $X$ une hypersurface lisse de degr\'e $\delta \geq 4$ dans $\pp ^3$ telle que $Pic(X)=Z$. On d\'esigne par $M_X(c_2)$ l'espace de modules des fibr\'es vectoriels sur $X$ de classes de Chern $c_1 = 0$ et $c_2$, semi-stables par rapport au diviseur ... More
Coisotropic Subalgebras of Complex Semisimple Lie BialgebrasSep 03 2014In his paper "A Construction for Coisotropic Subalgebras of Lie Bialgebras", Marco Zambon gave a way to use a long root of a complex semisimple Lie biaglebra $\mathfrak{g}$ to construct a coisotropic subalgebra of $\mathfrak{g}$. In this paper, we generalize ... More
Arithmetic, First-Order Logic, and Counting QuantifiersNov 19 2002This paper gives a thorough overview of what is known about first-order logic with counting quantifiers and with arithmetic predicates. As a main theorem we show that Presburger arithmetic is closed under unary counting quantifiers. Precisely, this means ... More
Measurements of Proton Structure Functions, alpha_s and Parton Distribution Functions at HERAMay 30 2003Jun 02 2003The measurement and QCD analysis of neutral and charged current cross sections at HERA are presented. For the kinematic range of four-momentum transfer Q^2 between approx. 1 GeV^2 and 30000 GeV^2 and Bjorken x between 0.0013 and 0.65 the data are compared ... More
Boosting for Functional DataMay 30 2006We deal with the task of supervised learning if the data is of functional type. The crucial point is the choice of the appropriate fitting method (learner). Boosting is a stepwise technique that combines learners in such a way that the composite learner ... More
Optical Spectroscopy as a Probe of Gaps and Kinetic Electronic Energy in p- and n-type cupratesOct 11 2006The real part of the optical in-plane conductivity of p-- and n--type cuprates thin films at various doping levels was deduced from highly accurate reflectivity measurements. We present here a comprehensive set of optical spectral weight data as a function ... More
Status of EXO-200Sep 09 2009EXO-200 is the first phase of the Enriched Xenon Observatory (EXO) experiment, which searches for neutrinoless double beta decay in 136Xe to measure the mass and probe the Majorana nature of the neutrino. EXO-200 consists of 200 kg of liquid Xe enriched ... More
Lower Bounds for Multi-Pass Processing of Multiple Data StreamsFeb 10 2009This paper gives a brief overview of computation models for data stream processing, and it introduces a new model for multi-pass processing of multiple streams, the so-called mp2s-automata. Two algorithms for solving the set disjointness problem wi th ... More
Support varieties and the Hochschild cohomology ring modulo nilpotenceNov 27 2008Dec 05 2008This is a survey paper based on my talks at the 41st Symposium on Ring Theory and Representation Theory, held in Shizuoka University, Japan in September 2008, and will appear in the conference proceedings. The paper begins with a brief introduction to ... More
Leading logarithmic QCD corrections to the B_s --> γγdecay rate including long-distance effects through B_s --> φγ--> γ γApr 23 1997Feb 02 1998We present leading logarithmic QCD corrections to the decay B_s --> \gamma\gamma in the Standard Model. Further, the form factor F_{1}(0) of B_s --> \phi\gamma is calculated in the framework of QCD sum rules and found to be in agreement with the result ... More
Predictions for $B \to K γγ$ decaysNov 26 2004Oct 15 2011We present a phenomenological study of the rare double radiative decay $B\to K \gamma\gamma$ in the Standard Model (SM) and beyond. Using the operator product expansion (OPE) technique, we estimate the short-distance (SD) contribution to the decay amplitude ... More
Phenomenological study of the double radiative decay $B ->Kγγ$Nov 29 2005Using the operator product expansion (OPE) technique, we study the rare double radiative decay $B\to K \gamma\gamma$ in the Standard Model (SM) and beyond. We estimate the short-distance (SD) contribution to the decay amplitude in a region of the phase ... More
Generalized Heat Kernel Coefficients for a New Asymptotic ExpansionDec 13 2002The method which allows for asymptotic expansion of the one-loop effective action W=ln det A is formulated. The positively defined elliptic operator A= U + M^2 depends on the external classical fields taking values in the Lie algebra of the internal symmetry ... More
Path integral bosonization of the 't Hooft determinant: fluctuations and multiple vacuaApr 16 2002Jun 03 2002The 't Hooft six quark flavor mixing interaction (N_f=3) is bosonized by the path integral method. The considered complete Lagrangian is constructed on the basis of the combined 't Hooft and U(3)X U(3) extended chiral four fermion Nambu-Jona-Lasinio interactions. ... More
Path Integral Bosonization of the 't Hooft Determinant: Quasiclassical CorrectionsJul 03 2003Mar 24 2004The many-fermion Lagrangian which includes the 't Hooft six-quark flavor mixing interaction (N_f=3) and the U_L(3)\times U_R(3) chiral symmetric four-quark Nambu -- Jona-Lasinio (NJL) type interactions is bosonized by the path integral method. The method ... More
Estimate of the long-distance contribution through b --> s ψto the B_{s} --> γγdecay rateAug 27 1997The B_{s} --> \phi\psi decay is modeled through the inclusive b --> s\psi decay. Using the Vector Meson Dominance model, the amplitude for the chain process B_{s} --> \phi\psi --> \phi\gamma --> \gamma\gamma is estimated and it is found to be at most ... More
One-loop fermion determinant with explicit chiral symmetry breakingJun 07 2000We use a proper-time regularization to define the one-loop fermion determinant for the case in which explicit chiral symmetry breaking takes place. We show how to obtain the polynomial by which the standard definition of lndetD needs to be modified in ... More
't Hooft determinant: Fluctuatioins and Multiple VacuaJan 06 2003The 't Hooft six quark flavor mixing interaction (N_f=3) is bosonized by the path integral method. The considered complete Lagrangian is constructed on the basis of the combined 't Hooft and U(3)X U(3) extended chiral four fermion Nambu -- Jona-Lasinio ... More
Effective Chiral Meson Lagrangian For The Extended Nambu-Jona-Lasinio ModelJul 11 2000We present a derivation of the low-energy effective meson Lagrangian of the extended Nambu -- Jona-Lasinio (ENJL) model. The case with linear realization of broken $SU(2)\times SU(2)$ chiral symmetry is considered. There are two crucial points why this ... More
Dynamical Galois groups of trinomials and Odoni's conjectureSep 12 2016We prove Odoni's conjecture in all prime degrees; namely, we prove that for every positive prime $p$, there exists a degree $p$ polynomial $\varphi\in\mathbb{Z}[x]$ with surjective arboreal Galois representation. We also show that Vojta's conjecture implies ... More
Parallelizing Spectral Algorithms for Kernel LearningOct 24 2016Nov 13 2016We consider a distributed learning approach in supervised learning for a large class of spectral regularization methods in an RKHS framework. The data set of size n is partitioned into $m=O(n^\alpha)$, $\alpha \leq \frac{1}{2}$, disjoint subsets. On each ... More
Optimal Rates For Regularization Of Statistical Inverse Learning ProblemsApr 14 2016We consider a statistical inverse learning problem, where we observe the image of a function $f$ through a linear operator $A$ at i.i.d. random design points $X_i$, superposed with an additive noise. The distribution of the design points is unknown and ... More
Kernel Partial Least Squares is Universally ConsistentFeb 25 2009Jan 14 2010We prove the statistical consistency of kernel Partial Least Squares Regression applied to a bounded regression learning problem on a reproducing kernel Hilbert space. Partial Least Squares stands out of well-known classical approaches as e.g. Ridge Regression ... More
Equivariant Euler characteristics of discriminants of reflection groupsJan 16 2002Let G be a finite, complex reflection group and f its discriminant polynomial. The fibers of f admit commuting actions of G and a cyclic group. The virtual $G\times C_m$ character given by the Euler characteristic of the fiber is a refinement of the zeta ... More
T=0 effective interaction in 14N and 10BNov 20 2007We have calculated the 1+ and 3+, T=0 states in 14N and 10B. In a neutron-proton RPA model these two nuclei are described by the same set of equations. We first show that a bare Minnesota interaction leads to too weak binding in bothnuclei. Furthermore ... More
Deformation or spherical symmetry in 10Be and the inversion of 1/2- - 1/2+ states in 11BeNov 20 2007For a core plus one neutron system like 11Be we have calculated the energies of the 1/2- and 1/2+ states assuming a deformation of the core deduced from the low energy 2+ state properties or taking into account the coupling of the neutron with this 2+ ... More
Dynamical Galois groups of trinomials and Odoni's conjectureSep 12 2016Oct 13 2016We prove Odoni's conjecture in all prime degrees; namely, we prove that for every positive prime $p$, there exists a degree $p$ polynomial $\varphi\in\mathbb{Z}[x]$ with surjective arboreal Galois representation. We also show that Vojta's conjecture implies ... More
Superspecial Abelian Varieties and the Eichler Basis Problem for Hilbert Modular FormsNov 02 2007Jun 17 2008Let $p$ be an unramified prime in a totally real field $L$ such that $h^+(L)=1$. Our main result shows that Hilbert modular newforms of parallel weight two for $\Gamma_0(p)$ can be constructed naturally, via classical theta series, from modules of isogenies ... More
Partially Observable Risk-Sensitive Markov Decision ProcessesApr 14 2015Nov 29 2016We consider the problem of minimizing a certainty equivalent of the total or discounted cost over a finite and an infinite time horizon which is generated by a Partially Observable Markov Decision Process (POMDP). The certainty equivalent is defined by ... More
Towards an Understanding of GRB Prompt EmissionFeb 07 2002We discuss the prompt emission of Gamma-Ray Bursts in different spectral energy bands. First, we suggest that a three-part synchrotron emission model is a good description of the ~20 keV - 1 MeV gamma-ray emission of GRBs. We show that this model provides ... More
Mirror matter and heavy singlet neutrino oscillations in the early universeMar 09 2000We investigate the mixing of heavy gauge singlet neutrinos in a mirror matter model employing the seesaw mechanism. The parameter constraints that must be satisfied to prevent the overproduction of mirror matter in the early universe are deduced. We find ... More
A note on monadic datalog on unranked treesOct 04 2013In the article 'Recursive queries on trees and data trees' (ICDT'13), Abiteboul et al., asked whether the containment problem for monadic datalog over unordered unranked labeled trees using the child relation and the descendant relation is decidable. ... More
Revealing the Asymmetry of the Wind of the Variable Wolf-Rayet Star WR1 (HD4004) Through SpectropolarizationAug 27 2013In this paper, high quality spectropolarimetric observations of the Wolf-Rayet (WR) Star WR1 (HD4004) obtained with ESPaDOnS at CFHT are presented. All major emission lines present in the spectrum show depolarization in the relative Stokes parameters ... More
On the charge of nanograins in cold environments and Enceladus dustJun 10 2013In very-low energy plasmas, the size of nanograins is comparable to the distance (the so-called Landau length) at which the interaction energy of two electrons equals their thermal energy. In that case, the grain's polarization induced by approaching ... More
Modeling of macroscopic stresses in a dilute suspension of small weakly inertial particlesJul 30 2015In this paper we derive asymptotically the macroscopic bulk stress of a suspension of small inertial particles in an incompressible Newtonian fluid. We apply the general asymptotic framework to the special case of ellipsoidal particles and show the resulting ... More
Optimal Dividend Payout Model with Risk Sensitive PreferencesMay 31 2016We consider a discrete-time dividend payout problem with risk sensitive shareholders. It is assumed that they are equipped with a risk aversion coefficient and construct their discounted payoff with the help of the exponential premium principle. This ... More
Hochschild cohomology of socle deformations of a class of Koszul self-injective algebrasMay 18 2009Feb 23 2010We consider the socle deformations arising from formal deformations of a class of Koszul self-injective special biserial algebras which occur in the study of the Drinfeld double of the generalized Taft algebras. We show, for these deformations, that the ... More
Kernel regression, minimax rates and effective dimensionality: beyond the regular caseNov 12 2016We investigate if kernel regularization methods can achieve minimax convergence rates over a source condition regularity assumption for the target function. These questions have been considered in past literature, but only under specific assumptions about ... More
Zero-sum Risk-Sensitive Stochastic GamesApr 07 2016Jun 29 2016In this paper we consider two-person zero-sum risk-sensitive stochastic dynamic games with Borel state and action spaces and bounded reward. The term risk-sensitive refers to the fact that instead of the usual risk neutral optimization criterion we consider ... More
Fluctuation theorem for out-of-time-ordered correlatorAug 31 2016The out-of-time-ordered correlator (OTOC) diagnoses quantum chaos and the scrambling of quantum information via the spread of entanglement. The OTOC encodes forward and reverse evolutions and has deep connections with the flow of time. So do fluctuation ... More
Chaotic Motions of F-Ring ShepherdsMay 20 2002Recent HST images of the Saturnian satellites Prometheus and Pandora show that their longitudes deviate from predictions of ephemerides based on Voyager images. Currently Prometheus is lagging and Pandora leading these predictions by somewhat more than ... More
A family of Koszul self-injective algebras with finite Hochschild cohomologyMay 11 2011This paper presents an infinite family of Koszul self-injective algebras whose Hochschild cohomology ring is finite-dimensional. Moreover, for each $N \geq 5$ we give an example where the Hochschild cohomology ring has dimension $N$. This family of algebras ... More