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The quantum extension of classical finite elements, referred to as quantum finite elements (QFE) [R. C. Brower et al., Lattice ��4 field theory on Riemann manifolds: Numerical tests for the 2-d Ising CFT on S2, Phys. Rev. D 98, 014502 (2018). and R. C. Brower et al., Lattice dirac fermions on a simplicial Riemannian manifold, Phys. Rev. D 95, 114510 (2017).], is applied to the radial quantization of 3D ��4 theory on a simplicial lattice for the R �� S2 manifold. Explicit counterterms to cancel the one- and two-loop ultraviolet defects are implemented to reach the quantum continuum theory. Using the Brower-Tamayo [Embedded Dynamics for ��4 Theory, Phys. Rev. Lett. 62, 1087 (1989).] cluster Monte Carlo algorithm, numerical results support the QFE ansatz that the critical conformal field theory (CFT) is reached in the continuum with the full isometries of R �� S2 restored. The Ricci curvature term, while technically irrelevant in the quantum theory, is shown to dramatically improve the convergence, opening the way for high precision Monte Carlo simulation to determine the CFT data; operator dimensions, trilinear operator product expansion couplings, and the central charge.

The quantum extension of classical finite elements, referred to as quantum finite elements ({\bf QFE})~\cite{Brower:2018szu,Brower:2016vsl}, is applied to the radial quantization of 3d $��^4$ theory on a simplicial lattice for the $\mathbb R \times \mathbb S^2$ manifold. Explicit counter terms to cancel the one- and two-loop ultraviolet defects are implemented to reach the quantum continuum theory. Using the Brower-Tamayo~\cite{Brower:1989mt} cluster Monte Carlo algorithm, numerical results support the QFE ansatz that the critical conformal field theory (CFT) is reached in the continuum with the full isometries of $\mathbb R \times \mathbb S^2$ restored. The Ricci curvature term, while technically irrelevant in the quantum theory, is shown to dramatically improve the convergence opening, the way for high precision Monte Carlo simulation to determine the CFT data: operator dimensions, trilinear OPE couplings and the central charge., 8 pages, 7 figures

We present a method for defining a lattice realization of the $��^4$ quantum field theory on a simplicial complex in order to enable numerical computation on a general Riemann manifold. The procedure begins with adopting methods from traditional Regge Calculus (RC) and finite element methods (FEM) plus the addition of ultraviolet counter terms required to reach the renormalized field theory in the continuum limit. The construction is tested numerically for the two-dimensional $��^4$ scalar field theory on the Riemann two-sphere, $\mathbb{S}^2$, in comparison with the exact solutions to the two-dimensional Ising conformal field theory (CFT). Numerical results for the Binder cumulants (up to 12th order) and the two- and four-point correlation functions are in agreement with the exact $c = 1/2$ CFT solutions., 52 pages, 27 figures

We present the spectrum of baryons in a new SU(4) gauge theory with fundamental fermion constituents. The spectrum of these bosonic baryons is of significant interest for composite dark matter theories. Here, we compare the spectrum and properties of SU(3) and SU(4) baryons, and then compute the dark-matter direct detection cross section via Higgs boson exchange for TeV-scale composite dark matter arising from a confining SU(4) gauge sector. Comparison with the latest LUX results leads to tight bounds on the fraction of the constituent-fermion mass that may arise from electroweak symmetry breaking. Lattice calculations of the dark matter mass spectrum and the Higgs-dark matter coupling are performed on quenched $16^{3} \times 32$, $32^{3} \times 64$, $48^{3} \times 96$, and $64^{3} \times128$ lattices with three different lattice spacings, using Wilson fermions with moderate to heavy pseudoscalar meson masses. Our results lay a foundation for future analytic and numerical study of composite baryonic dark matter., Comment: 18 pages, 18 figures

Lattice radial quantization was proposed in a recent paper by Brower, Fleming and Neuberger[1] as a nonperturbative method especially suited to numerically solve Euclidean conformal field theories. The lessons learned from the lattice radial quantization of the 3D Ising model on a longitudinal cylinder with 2D Icosahedral cross-section suggested the need for an improved discretization. We consider here the use of the Finite Element Methods(FEM) to descretize the universally-equivalent $\phi^4$ Lagrangian on $\mathbb R \times \mathbb S^2$. It is argued that this lattice regularization will approach the exact conformal theory at the Wilson-Fisher fixed point in the continuum. Numerical tests are underway to support this conjecture., Comment: 8 pages, 7 pages

We present our calculations of the electromagnetic form factor of pions. We explore the properties of pion form factor at momentum transfer larger than previous studies by including more combinations of source and sink momenta and using more configurations.We fit our results using vector meson dominance (VMD) hypothesis., Comment: 7 pages, 6 figures. Talk given at 25th International Symposium on Lattice Field Theory, Regensburg, Germany, 30 Jul - 4 Aug 2007

Euclidean-time hadron correlation functions computed in Lattice QCD (LQCD) are modeled by a sum of decaying exponentials, reminiscent of the exponentially damped sinusoid models of free induction decay (FID) in Nuclear Magnetic Resonance (NMR) spectroscopy. We present our initial progress in studying how data modeling techniques commonly used in NMR perform when applied to LQCD data., Comment: 11 pages, svmult.cls. Minor changes in response to reviewers' comments. To appear in the Proceedings of the Third International Workshop on Numerical Analysis and Lattice QCD, Edinburgh, Scotland, 30 Jun - 04 Jul 2003

A standing mystery in the Standard Model is the unnatural smallness of the strong CP violating phase. A massless up quark has long been proposed as one potential solution. A lattice calculation of the constants of the chiral Lagrangian essential for the determination of the up quark mass, 2 alpha_8 - alpha_5, is presented. We find 2 alpha_8 - alpha_5 = 0.29 +/- 0.18, which corresponds to m_u / m_d = 0.410 +/- 0.036. This is the first such calculation using a physical number of dynamical light quarks, N_f = 3., Comment: 4 pages, 5 figures, submitted to Phys. Rev. Lett., corrected small normalization error in f_pi (conclusions were unaffected), improved lattice spacing analysis, improved finite volume analysis

The Young Physicists Panel (YPP) summarizes results from their Survey on the Future of High Energy Physics, which was conducted from July 2 to July 15, 2001. Over 1500 physicists from around the world, both young and tenured, responded to the survey. We first describe the origin, design, and advertisement of the survey, and then present the demographics of the respondents. Following sections analyze the collected opinions on the desire for balance in the field, the impact of globalization, the necessity of outreach, how to build the field, the physics that drives the field, and the selection of the next big machine. Respondents' comments follow the survey analysis in an appendix., There is a short form and a long form of the document. The short form consists of 42 pages: the discussion, 39 figures, and a copy of the survey. The long form is comprised of that same 42 pages, followed by all the "brief comments" written by survey respondents, for a total of 208 pages