Ling-Fong Li

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Bloom syndrome is more common in individuals of Ashkenazi Jewish descent than in any other population, and one particular mutation in the Bloom syndrome gene, blmAsh, is homozygous in nearly all Ashkenazi Jewish persons with Bloom syndrome. We have determined the frequency of blmAsh in 1491 Ashkenazi Jewish persons with no known history of Bloom syndrome(More)
In this introductory lecture, some basic features of the spontaneous symmetry breaking are discussed. More specifically, σ-model, non-linear realization, and some examples of spontaneous symmetry breaking in the non-relativistic system are discussed in details. The approach here is more pedagogical than rigorous and the purpose is to get some simple(More)
We examine in detail the possibility of using the Higgs mechanism to remove the catastrophic infrared singularities in non-Abe&n gauge theories which are symptotically free. Our investigation encompasses theories based on SU(N) or O(N) with scalars in one vector, two vector, M vector, adjoint, tensor and adjoint plus one vector representations. We find that(More)
One way to detect the presence of new particles in theories beyond the standard model is through their contribution to electroweak loop effects. We comment on the importance of a consistent inclusion of their mixing angles to ensure that the physical requirement of heavy particle decoupling is fulfilled. We illustrate our points by a detailed discussion of(More)
We compute the oblique parameters, including the three new parameters V , W and X introduced recently by the Montreal group, for the case of one scalar multiplet of arbitrary weak isospin J and weak hypercharge Y . We show that, when the masses of the heaviest and lightest components of the multiplet remain constant, but J increases, the oblique parameter U(More)
A whole class of non-perturbative QCD studies (e.g. the instanton models, chiral quark models, etc.) indicates that the effective degrees of freedom for the physics in the low Q . 1GeV 2 region could be the constituent quarks(CQs) and internal Goldstone bosons (IGBs). This leads to a nucleon structure with the spin being carried by three constituent quark(More)
  • 1973
The patterns of symmetry breaking in the gauge theories are investigated systematically in the general rotation groups and unitary groups, with Higgs scalars in the various representations up to second rank tensors. The occurrences of the fermion mass relations and pseudo-Goldstone bosons are also discussed in various cases. (Submitted to Phys. Rev.) * Work(More)
The possibility that higher dimensional field theories are broken spontaneously, through the usual Nambu-Goldstone mechanism, to 4dimension is explored. As a consequence, vector Goldstone bosons can arise in this breaking of Lorentzian symmetry from higher dimension to 4-dimension. This can provide a simple mechanism for reduction to 4-dimension in theories(More)