General Issues in the Evolution of Fermion Masses and Mixings

General issues in the renormalization group evolution of fermion masses and mixings is discussed. An effective fixed point in the top quark Yukawa coupling can strongly constrain its value at the electroweak scale. Predictions following from Yukawa coupling unification are affected by threshold corrections at the grand unified scale. The Landau pole translates into an upper limit on the strong gauge coupling $\alpha _3(M_Z)$. Given the hierarchy in the fermion sector, the evolution of the Cabbibo-Kobayashi-Maskawa matrix can be expressed in terms of a single scaling parameter $S$. Using this scaling factor and analogous scaling factors for the quark and lepton masses, we outline a systematic strategy that readily yields electroweak predictions for any GUT scale texture.}Comment: (Talk given at the SUSY93 Conference MSB), 9 pages + 3 PS figures not included (available on request), MAD/PH/75

Supersymmetry with Grand Unification

Supersymmetry (SUSY) has many well known attractions, especially in the context of Grand Unified Theories (GUTs). SUSY stabilizes scalar mass corrections (the hierarchy problem), greatly reduces the number of free parameters, facilitates gauge coupling unification, and provides a plausible candidate for cosmological dark matter. In this conference report we survey some recent examples of progress in SUSY-GUT applications.Comment: Talk V. Barger at the Workshop on Physics at Current Accelerators and the Supercollider, Argonne, June 1993, 15 pages + 12 PS figures included (uuencoded), (correct author list in header) MAD/PH/78

Heavy Higgs Bosons at TeV e+e- Colliders

We summarize the work done by the European working group on Higgs Particles for the Workshop ``Physics with e$^+$e$^-$ Linear Colliders", Annecy--Gran Sasso--Hamburg, Feb.--Sept. 1995. The main focus will be on the physics possibilities at a second phase e$^+$e$^-$ linear collider with a center of mass energy of $\sim 1.5$ TeV.Comment: 14 pages in Latex with 5 figures separately sent in a uuencode file, The complete postscript file is also available via WWW at http://itpaxp1.physik.uni-karlsruhe.de/prep/prep.htm

Supergravity Solutions in the Low-tan⁡β\tan\beta λt \lambda_t Fixed Point Region

There has been much discussion in the literature about applying the radiative electroweak symmetry breaking (EWSB) requirement to GUT models with supergravity. We motivate and discuss the application of the EWSB requirement to the low $\tan\beta$ fixed-point region and describe the solutions we find.Comment: Talk presented by P. Ohmann at the Second IFT Workshop: Yukawa Couplings and the Origins of Mass, Gainesville, Florida, February 11--13, 1994. Standard Latex, 11 pages with figures. Uses epsf.sty to incorporate 4 postscript figures (uufiled and submitted via figures command). Can be texed without figures. Hardcopies available by conventional mail upon request. MAD/PH/82