Events at Physics |
Events on Tuesday, September 23rd, 2014
- Chaos & Complex Systems Seminar
- Wisconsin State Energy Office – Forecasting, monitoring, and responding to energy crises
- Time: 12:05 pm - 1:00 pm
- Place: 4274 Chamberlin Hall (Refreshments will be served)
- Speaker: Jim Mapp, Dark Energy Associates
- Abstract: Since the 1970s Wisconsin has experienced several petroleum crises, natural gas supply limitations, coal shortages, and electric power brownouts, blackouts and supply uncertainty. There have been crises related to propane shortages, extremes in cold weather, hot weather, rain events, and floods. We will discuss the role of the Wisconsin State Energy Office in forecasting, preparing for, monitoring and responding to these various energy related crises and the often chaotic conditions surrounding these events. This past winter’s propane shortage provided an example of a recent energy crisis. Propane as a liquid fuel is used for crop drying, home heating in rural areas, and as a supplemental fuel in areas where natural gas is not available. The coming fall and winter heating season may provide an example of the various factors that combine to generate chaos in the supply and demand of propane and steps that can be taken to respond to a possible crisis. Possible supply constraints may include; propane pipeline supply limitations, expanded propane export market, limitations on rail car availability, wet harvest conditions and record corn harvest leading to increased demand for propane for crop drying. Early onset of cold weather could increase the demand for heating fuels such as propane. Possible responses may include coordinating efforts with other Wisconsin agencies, other states, various federal authorities, or various national organizations.
- Host: Clint Sprott
- Theory Seminar (High Energy/Cosmology)
- The Goldstone Exception: Spontaneously broken global symmetry, i.e. the Goldstone theorem, protects the Higgs from a Fine Tuning (FT) Problem
- Time: 3:00 pm - 4:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Bryan Lynn, University College London and Case Western University
- Abstract: More than four decades ago, B.W. Lee and K. Symanzik proved that, in the O(4) Gell-Mann Levy (GML) model with Partially Conserved Axial-vector Currents (PCAC), global Ward Takahashi Identities (WTI) force all Ultra-Violet Quadratic Divergences (UVQD) into the renormalized pseudo Nambu-Goldstone-Boson (NGB) pion mass-squared. Tadpole renormalization is un-necessary.
We prove (to all-orders perturbations) that all UVQD, together with all other relevant operators, therefore vanish identically in GML’s spontaneous symmetry broken (SSB) Goldstone-mode, where pions are true NGB (i.e. exactly massless). A weak-scale Higgs mass is natural in SSB GML, the Higgs mass and vacuum expectation value (VEV) are stable against quantum corrections and not FT: SSB GML has no Higgs FT problem. Neither do the SSB O(4) Schwinger model (PCAC=0) or the Standard Model (SM). No-Higgs-FT is simply another (albeit unfamiliar) consequence of WTI and the Goldstone Theorem.
A huge class of high-mass-scale (M_{Heavy}>>m_{Higgs}) extensions of GML, Schwinger and SM also demonstrate naturalness, no-FT and heavy particle decoupling. We display two examples: a heavy (M_S >> m_{Higgs}) real scalar field; and a right-handed Type 1 See-Saw Majorana neutrino with M_R >> m_{Higgs}. We prove that for |q^2| << M_{Heavy}^2, the heavy degrees of freedom contribute only irrelevant and marginal operators. Phenomenological consequences include the renewed possibility of thermal lepto-genesis in the neutrino-MSM. It is also easy to construct no-Higgs-FT models with very high-scale SUSY breaking.
We conjecture that, since classical General Relativity (GR) couples democratically to spin=0, ½ and 1 quantum particles, GR+SM (and maybe certain quantum gravity theories) will also retain naturalness, avoiding FT problems. Absent a SM FT problem, there should be no expectation that LHC14 will discover physics beyond the SM which is unrelated to neutrino mixing, the only known experimental failure of the SM. - Host: Ran Lu