The LSND Experiment and the Zee Model

A recent experiment LSND at Los Alamos has provided\cite{1} an indication of $\overline{\nu}_{\mu} - \overline{\nu}_e$ oscillations with $\Delta m^2$ of order 1ev$^2$ or greater and $\sin^2 2 \theta_{e \mu}$ between $2 \times 10^{-3}$ and $10^{2}$. Such a value of $\Delta m^2$ for $\nu_{\mu} - \nu_e$ oscillations was not expected in the standard see-saw model\cite{2} suggested by SO(10) with a large mass hierarchy because it leads to too large a value of $m(\nu_{\tau})$ to fit cosmological constraints. Furthermore within that model the LSND result is inconsistent with the indications of oscillations from both atmospheric neutrinos\cite{3} and solar neutrinos.\cite{4}Comment: 3 pages, latex, no figure

CP Violation in D0−D0‾D^0-\overline{D^0}Mixing

The existence of $D^0-\overline{D^0}$ mixing at a detectable level requires new physics, which effectively yields a $\Delta c = 2$ superweak interaction. In general this interaction may involve significant CP violation. For small values of the mixing it may be much easier to detect the CP-violating part of the mixing than the CP-conserving part.Comment: 3 pages, latex, no figure

Using the value of beta to help determine gamma from B decays

It has been pointed out by Gronau and Rosner that the angle gamma of the unitarity triangle could be determined by combining future results on B_s and B_d decays to K pi. Here we show that it is important to include in the analysis the information on the phase beta which will be determined in the near future. Omitting this information could lead to an error as large as 8 degrees in gamma.Comment: 7 pages, 2 figures; revised version for journal submission; some points clarifie

The neutrino ground state in a neutron star

We address a recent claim that the stability of neutron stars implies a lower bound on the mass of the neutrino. We argue that the result obtained by some previous authors is due to an improper summation of an infrared-sensitive series and that a non-perturbative "resummation" of the series yields a finite and well-behaved result. The stability of neutron stars thus gives no lower bound on the mass of the neutrino.Comment: 5 pages, 3 figures, Latex (uses espcrc2.sty); contribution to the proceedings of Neutrino 98, Takayama, Japan, 4-9 June, 199

Strong Phases in the Decays B to pi pi

Two sources of strong phases in the decays $B$ to $\pi\pi$ are identified: (1) "quasi-elastic scattering" corresponding to intermediate states like $\pi\pi$ and $\rho\rho$, (2) ``$c\bar{c}$'' corresponding to intermediate states like $D\bar{D}$ and $D^{*}\bar{D}^{*}$. Possibilities of using data to identify these two sources are discussed and illustrated. Present data suggests both sources may be significant.Comment: 6 pages, 1 figure

CP Violation

Three possibilities for the origin of CP violation are discussed: (1) the Standard Model in which all CP violation is due to one parameter in the CKM matrix, (2) the superweak model in which all CP violation is due to new physics and (3) the Standard Model plus new physics. A major goal of B physics is to distinguish these possibilities. CP violation implies time reversal violation (TRV) but direct evidence for TRV is difficult to obtain.Comment: 13 pages, to be published in Lecture Notes of TASI-2000, edited by Jonathan L. Rosner, World Scientific, 200

Toward a Neutrino Mass Matrix

One may identify the general properties of the neutrino mass matrix by generating many random mass matrices and testing them against the results of the neutrino experiments.Comment: 3 pages, 1 figure, talk at DPF200