Clebsch Potentials in the Variational Principle for a Perfect Fluid

Equations for a perfect fluid can be obtained by means of the variational principle both in the Lagrangian description and in the Eulerian one. It is known that we need additional fields somehow to describe a rotational isentropic flow in the latter description. We give a simple explanation for these fields; they are introduced to fix both ends of a pathline in the variational calculus. This restriction is imposed in the former description, and should be imposed in the latter description. It is also shown that we can derive a canonical Hamiltonian formulation for a perfect fluid by regarding the velocity field as the input in the framework of control theory.Comment: 15 page

Probing Higgs self-coupling of a classically scale invariant model in e+e−→Zhhe^+e^- \to Zhh: Evaluation at physical point

A classically scale invariant extension of the standard model predicts large anomalous Higgs self-interactions. We compute missing contributions in previous studies for probing the Higgs triple coupling of a minimal model using the process $e^+e^- \to Zhh$. Employing a proper order counting, we compute the total and differential cross sections at the leading order, which incorporate the one-loop corrections between zero external momenta and their physical values. Discovery/exclusion potential of a future $e^+e^-$ collider for this model is estimated. We also find a unique feature in the momentum dependence of the Higgs triple vertex for this class of models.Comment: 14 pages, 7 figures; Version to appear in Phys. Lett.

Clebsch Potentials in the Variational Principle for a Perfect Fluid

Equations for a perfect fluid can be obtained by means of the variational principle both in the Lagrangian description and in the Eulerian one. It is known that we need additional fields somehow to describe a rotational isentropic flow in the latter description. We give a simple explanation for these fields; they are introduced to fix both ends of a pathline in the variational calculus. This restriction is imposed in the former description, and should be imposed in the latter description. It is also shown that we can derive a canonical Hamiltonian formulation for a perfect fluid by regarding the velocity field as the input in the framework of control theory.Comment: 15 page

A Variational Principle for Dissipative Fluid Dynamics

In the variational principle leading to the Euler equation for a perfect fluid, we can use the method of undetermined multiplier for holonomic constraints representing mass conservation and adiabatic condition. For a dissipative fluid, the latter condition is replaced by the constraint specifying how to dissipate. Noting that this constraint is nonholonomic, we can derive the balance equation of momentum for viscous and viscoelastic fluids by using a single variational principle. We can also derive the associated Hamiltonian formulation by regarding the velocity field as the input in the framework of control theory.Comment: 15 page

持久運動時の脂肪代謝調節機構に関する研究

京都大学0048新制・課程博士博士(農学)甲第19042号農博第2120号新制||農||1032(附属図書館)学位論文||H27||N4924(農学部図書室)31993京都大学大学院農学研究科食品生物科学専攻(主査)教授 伏木 亨, 教授 保川 清, 教授 金本 龍平学位規則第4条第1項該当Doctor of Agricultural ScienceKyoto UniversityDGA

Why a Particle Physicist is Interested in DNA Branch Migration

We describe an explicitly discrete model of the process of DNA branch migration. The model matches the existing data well, but we find that branch migration along long strands of DNA (N \simge 40~bp) is also well modeled by continuum diffusion. The discrete model is still useful for guiding future experiments.Comment: Talk presented at LATTICE96(theoretical developments); 3 pages, TeXsis w/ LAT96.txs (available from ftp://lifshitz.ph.utexas.edu/texsis/styles/LAT96.txs and will be a part of the next Elsevier.txs) and TXSdcol.te