Conformal technicolor

We point out that the flavor problem in theories with dynamical electroweaksymmetry breaking can be effectively decoupled if the physics above the TeVscale is strongly conformal, and the electroweak order parameter has a scalingdimension d = 1 + epsilon with epsilon \simeq 1/few. There are manyrestrictions on small values of epsilon: for epsilon << 1, electroweak symmetrybreaking requires a fine-tuning similar to that of the standard model; large-Nconformal field theories (including those obtained from the AdS/CFTcorrespondence) require fine-tuning for d < 2; `walking technicolor' theoriescannot have d < 2, according to gap equation analyses. However, strong small-Nconformal field theories with epsilon \simeq 1/few avoid all these constraints,and can give rise to natural dynamical electroweak symmetry breaking with a topquark flavor scale of order 10^{1/epsilon} TeV, large enough to decoupleflavor. Small-N theories also have an acceptably small Peskin-Takeuchi Sparameter. This class of theories provides a new direction for dynamicalelectroweak symmetry breaking without problems from flavor or electroweakprecision tests. A possible signal for these theories is a prominent scalarresonance below the TeV scale with couplings similar to a heavy standard modelHiggs.Comment: 26 pages + References. Slight wording changes. Version appearing in JHE