A sonic boom in bubble wall friction

Electroweak Bubble Wall Friction: Analytic Results

We present an entirely analytic, leading log order determination of the friction an electroweak bubble wall feels during a first order electroweak phase transition. The friction is dominated by W bosons, and gives a wall velocity parametrically ∼ αw, and numerically small, ∼ .01 −− 0.1 depending on the Higgs mass.

Indoor Sonic Boom Reproduction Using ANC

ABSTRACT The European programs for development of supersonic air-flights involve new studies on the human perception of sonic boom. Because this noise includes high-level components at very low-frequency, the usual psycho-acoustic tests with headphones are not relevant; instead, the original sound-field can be reproduced with many loudspeakers in a small room, but the loudspeakers must be contr...

High friction on a bubble mattress.

Reducing the friction of liquid flows on solid surfaces has become an important issue with the development of microfluidics systems, and more generally for the manipulation of fluids at small scales. To achieve high slippage of liquids at walls, the use of gas as a lubricant--such as microbubbles trapped in superhydrophobic surfaces--has been suggested. The effect of microbubbles on the effecti...

Sonic Boom in the Little Bang at RHIC ?

The Big Bang Model is a widely accepted theory for the origin and evolution of our universe. It postulates that ∼ 12−14 billion years ago, a hot and dense plasma of quarks and gluons (QGP) was produced a few micro seconds after the “big bang”. A pervading uniform glow of cold cosmic microwave background provides an unequivocal signature for the subsequent expansion from this hot and dense state...

Automatic Differentiation for Optimum Design, Applied to Sonic Boom Reduction