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Solution to the Higgs naturalness problem. Zheng-Tao Wei Nankai University, Tianjin. The Ninth Particle Physics Phenomenology Workshop, 2011.6.3—2011.6.6, at NCU, Chungli, Taiwan. Beijing ↔ Tianjin, ½ hour by train. The highest building in the north China. Tianjin Binhai New Area:
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Solution to the Higgs naturalness problem Zheng-Tao Wei Nankai University, Tianjin The Ninth Particle Physics Phenomenology Workshop, 2011.6.3—2011.6.6, at NCU, Chungli, Taiwan.
Beijing ↔ Tianjin, ½ hour by train. The highest building in the north China. Tianjin Binhai New Area: the most admired industrial park; the most attractive investment area in China and even Asia as a whole.
Nankai University 我 是 愛 南 開 的 看 门 I love Nankai I am gardener of south gate Primier En-Lian Zhou (周恩来), Xing-Shen Chen (陈省身); Tao Han (韩涛), T.D. Lee, C.N. Yang, Ta-You Wu, ….
Z. Wei, L. Bian, arXiv:1104.2735. • Introduction: • Higgs naturalness problem • Our solution • Summary
Introduction • The SM is very successful. • Higgs mechanism provides mass for • everything. • The crucial purpose of LHC is to search • and study Higgs.
Higgs naturalness problem Fine-tuning: bare and counter-term fine-tuning at (102/1019)2~10-34; or Hierarchy: MP>>mH. Higgs is unnatural.
History The Origins of lattice gauge theory,Kenneth G. Wilson, 2004
Dimensional regularization is not physical. = c Λ2 • He did the first explicit calculations. To do is better than to say!
Some scenarios of solution: • Veltman’s condition: • New symmetry: • SUSY, scale invariance, … • New particle, dimension: • composite Higgs, little Higgs, • extra dimension, .…
A modern review on naturalness: arXiv: 0801.2562. Naturalness problems in physics: 1. Higgs mass, 2. fermion mass, 3. cosmological constant, …
Our solution to Higgs naturalness • Is it really a problem? • SM is renormalizable, mH independent of Λ. • What can the equation tell us? • -----Chuan-Hung Chen’s question • One-loop result may be misleading. • Some examples: • Asymptotic freedom, g->0, large Log • Sudakov form factor, F(Q2)->exp{-c’ln2(Q2/m2)} • large double-Log
Our idea • To study RG evolution of mH with energy • due to quadratic divergence. • What’s the asymptotic behavior of mH • in the short-distance?
Regularization and renormalization scheme Fujikawa’s idea: counter-term renormalized quantities • A new concept The bare quantities are the renormalized parameters at the UV limit. mH0=mH(μ→∞)
RGE for Higgs mass The bare mass is μ-independent, • The evolution is with respect to scale μ, • not lnμ. • The new mass anomalous dimension • is proportional to -mH2.
Solution of the RGE Where mV is called by “Veltman mass”. • The Higgs mass is an exponential damping • function when energy scale increases. • The Higgs mass in the UV limit approaches • “Veltaman mass” mV. • The bare mass is not divergent, but finite.
Peculiarity of the SM: • 1. The couplings are proportional to masses. • 2. The evolutions of coupling constants and • masses are correlated with each other.
Summary • The Higgs mass about 100 GeV order is stable. • The Higgs naturalness problem is solved by • radiative corrections themselves within SM. • New symmetry and new particles are • unnecessary.
人体是一个 自我调节系统。 Human body is a self-tuning system. SM
Thank you for your attentions. ButI am hungry.