Nonperturbative Pauli-Villars regularization of vacuum polarization in light-front QED

We continue the development of a nonperturbative light-front Hamiltonian method for the solution of quantum field theories by considering the one-photon eigenstate of Lorentz-gauge QED. The photon state is computed nonperturbatively for a Fock basis with a bare photon state and electron-positron pair states. The calculation is regulated by the inclusion of Pauli-Villars (PV) fermions, with one flavor to make the integrals finite and a second flavor to guarantee a zero mass for the physical photon eigenstate. We compute in detail the constraints on the PV coupling strengths that this zero mass implies. As part of this analysis, we provide the complete Lorentz-gauge light-front QED Hamiltonian with two PV fermion flavors and two PV photon flavors, which will be useful for future work. The need for two PV photons was established previously; the need for two PV fermions is established here.Comment: 13 pages, 1 figure, RevTeX 4.1; corrected typos and updated reference

Making sense of higher education: students as consumers and the value of the university experience

In the global university sector competitive funding models are progressively becoming the norm, and institutions/courses are frequently now subject to the same kind of consumerist pressures typical of a highly marketised environment. In the United Kingdom, for example, students are increasingly demonstrating customer-like behaviour and are now demanding even more ‘value’ from institutions. Value, though, is a slippery concept and has proven problematic both in terms of its conceptualisation and measurement. This article explores the relationship between student value and higher education and, via study in one United Kingdom business school, suggests how this might be better understood and operationalised. Adopting a combined qualitative/quantitative approach, this article also looks to identify which of the key value drivers has most practical meaning and, coincidentally, identifies a value-related difference between home and international students

Nonperturbative Renormalization of QED in Light-Cone Quantization

As a precursor to work on QCD, we study the dressed electron in QED nonperturbatively. The calculational scheme uses an invariant mass cutoff, discretized light-cone quantization, a Tamm--Dancoff truncation of the Fock space, and a small photon mass. Nonperturbative renormalization of the coupling and electron mass is developed.Comment: Latex, 4 pages, 1 figur

Anomalously light mesons in a (1+1)-dimensional supersymmetric theory with fundamental matter

We consider N=1 supersymmetric Yang-Mills theory with fundamental matter in the large-N_c approximation in 1+1 dimensions. We add a Chern-Simons term to give the adjoint partons a mass and solve for the meson bound states. Here mesons are color-singlet states with two partons in the fundamental representation but are not necessarily bosons. We find that this theory has anomalously light meson bound states at intermediate and strong coupling. We also examine the structure functions for these states and find that they prefer to have as many partons as possible at low longitudinal momentum fraction.Comment: 14 pages, 3 figures, LaTe

Sonoluminescence: Nature's Smallest BlackBody

The Spectrum of the light emitted by a sonoluminescing bubble is extremely well fit by the spectrum of a blackbody. Furthermore the radius of emission can be smaller than the wavelength of the light. Consequences, for theories of sonoluminescence are discussed.Comment: 8 pages, 3 Figure