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    Standard Model Electroweak Measurements at LEP
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    Abstract:
    The current status of electroweak physics results from LEP is reviewed. Particular emphasis is placed on the latest results on the properties of the Z and W bosons. The updated status of the global electroweak fit to the standard model and the resulting standard model Higgs mass limits are presented.
    Keywords:
    Technicolor
    Dynamical breaking of the electroweak theory, i.e. technicolor, is an intriguing extension of the Standard Model. Recently new models have been proposed featuring walking dynamics for a very low number of techniflavors. These technicolor extensions are not ruled out by current precision measurements. Here I first motivate the idea of dynamical electroweak symmetry breaking and then summarize some of the properties of the recent models and their possible cosmological implications.
    Technicolor
    I consider the possibility that electroweak symmetry is broken by a strongly interacting chiral gauge theory. I argue that some of the discrepancies between precision electroweak measurements and the predictions of QCD-like technicolor models can be resolved if technicolor is a chiral gauge theory. I present a toy technicolor model which demonstrates this idea, and gives mt ⪢ mb, with a small value for Δϱ∗ ≡ αT, and small corrections to Z → bb.
    Technicolor
    We show that the pseudo Nambu-Goldstone boson contribution to the Peskin-Takeuchi electroweak parameter S can be negative in a class of technicolor theories. This negative contribution can be large enough to cancel the positive technihadron contribution, showing that electroweak precision tests alone cannot be used to rule out technicolor as the mechanism of electroweak symmetry breaking.
    Technicolor
    Goldstone boson
    Citations (27)
    After briefly remarking on alternatives for breaking the electroweak symmetry, I discuss the implication that recent precision experiments at LEP have for the symmetry breaking sector. The difficulties associated with generating fermion masses when the electroweak symmetry is broken dynamically are exposed and an alternative to the walking technicolor - extended technicolor scenario is suggested, based on models of substructure. Failures and lessons from trying to incorporate families and mixing in these latter schemes are also discussed.
    Technicolor
    Substructure
    Citations (0)
    After briefly remarking on alternatives for breaking the electroweak symmetry, I discuss the implication that recent precision experiments at LEP have for the symmetry breaking sector. The difficulties associated with generating fermion masses when the electroweak symmetry is broken dynamically are exposed and an alternative to the walking technicolor - extended technicolor scenario is suggested, based on models of substructure. Failures and lessons from trying to incorporate families and mixing in these latter schemes are also discussed.
    Technicolor
    Substructure
    In this talk, I describe a few interesting physics beyond the standard model that are quite unique for $γγ$ collisions, including large extra dimension model (ADD), warped extra dimension model (Randall-Sundrum) model, universal extra dimension model, as well as techni-pions of technicolor models.
    Technicolor
    Unparticle physics
    Universal extra dimension
    Large extra dimension
    The electroweak radiative corrections induced by a one-family technicolor model are examined using the dispersion relation technique proposed by Peskin and Takeuchi. Large uncertainties in $\ensuremath{\Delta}r$ remain because its value is sensitive to the masses of the technipions and technirho.
    Technicolor
    Dispersion relation
    Citations (17)
    The current status of electroweak physics results from LEP is reviewed. Particular emphasis is placed on the latest results on the properties of the Z and W bosons. The updated status of the global electroweak fit to the standard model and the resulting standard model Higgs mass limits are presented.
    Technicolor
    Precision electroweak measurements have been claimed to eliminate almost all models of technicolor. We show that the assumptions made to calculate the oblique parameters $S$,$T$,$U$ apply to QCD--like technicolor models which were ruled out long ago on much firmer grounds. These assumptions are invalid in modern ``walking'' technicolor models.
    Technicolor
    Citations (1)