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Negative S parameter from holographic technicolor
1IFIC-Universitat de València, Edifici d'Instituts de Paterna, Apt. Correus 22085, 46071 València, Spain.
Physical Review Letters
|October 10, 2006
Summary
We introduce Holographic Technicolor, a new 5D model resolving the S parameter issue in electroweak scale physics. This model offers a vanishing or negative S parameter, crucial for viable Technicolor theories.
Area of Science:
- High Energy Physics
- Theoretical Physics
- Particle Physics
Background:
- Technicolor theories aim to explain electroweak symmetry breaking without the Higgs boson.
- A key challenge is the prediction of the S parameter, which must be small and positive in many models.
- Existing models often struggle to satisfy constraints on the S parameter, leading to 'no-go' theorems.
Purpose of the Study:
- To introduce a new class of 5D models, Holographic Technicolor.
- To demonstrate that these models can satisfy requirements for 4D strong dynamics at the electroweak scale.
- To address the S parameter problem within Technicolor frameworks.
Main Methods:
- Development of a new 5D model: Holographic Technicolor.
- Analysis within the large-N (N=number of colors) regime.
- Investigation of the 4D dual of the proposed 5D model.
Main Results:
- The Holographic Technicolor model provides a vanishing or negative tree-level S parameter.
- This circumvents existing 'no-go' theorems concerning the sign of the S parameter.
- The model's large-N description allows for computable S parameter corrections, suppressed by 1/N.
- Fermion mass generation and the S parameter issue are decoupled.
Conclusions:
- Holographic Technicolor presents a viable candidate for a 4D strong dynamics theory at the electroweak scale.
- The model offers a novel solution to the S parameter problem in Technicolor.
- The 4D dual suggests a walking Technicolor-like behavior with a large anomalous dimension.
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