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Quark nuggets are theoretical objects composed of approximately equal numbers of up, down, and strange quarks. They are also called strangelets, nuclearites, AQNs, slets, Macros, and MQNs. Quark nuggets are a candidate for dark matter, which has been a mystery for decades despite constituting ~ 85% of the universe's mass. Most previous models of quark nuggets have assumed no intrinsic magnetic field; however, Tatsumi found that quark nuggets may exist in magnetars as a ferromagnetic liquid with a magnetic field BS = 1012±1 T. We apply that result to quark nuggets, a dark-matter candidate consistent with the Standard Model, and report results of analytic calculations and simulations that show they spin up and emit electromagnetic radiation at ~ 104 to ~ 109 Hz after passage through planetary environments. The results depend strongly on the value of Bo, which is a parameter to guide and interpret observations. A proposed sensor system with three satellites at 51,000 km altitude illustrates the feasibility of using radio-frequency emissions to detect 0.003 to 1,600 MQNs, depending on Bo, during a 5 year mission. [ABSTRACT FROM AUTHOR]

The problem of a compressible gas flows over a flat plate with the velocity-slip and temperature-jump boundary conditions are being studied. The standard single- shooting method is applied to obtain the exact solutions for velocity and temperature profiles when the momentum and energy equations are weakly coupled. A double-shooting method is applied if these two equations are closely coupled. If the temperature affects the velocity directly, more significant velocity slip happens at locations closer to the plate's leading edge, and inflections on the velocity profiles appear, indicating flows may become unstable. As a consequence, the temperature-jump and velocity-slip boundary conditions may trigger earlier flow transitions from a laminar to a turbulent flow state. [ABSTRACT FROM AUTHOR]

We analyze the near continuum flow created by a rotating disk facing a stagnant gas. The flow-field properties change from the traditional continuum solutions, due to the introductions of new velocity-slip and temperature-jump boundary conditions. To compute the velocity profiles, a self-similar transformation simplifies the Navier-Stokes equations into a system of ordinary differential equations. The introduction of new boundary conditions generates new parameters which can be adjusted at different degrees of rarefaction. Shooting methods are adopted to solve the differential equations with the new boundary conditions. Based on the solved velocity profiles, exact solutions for the temperature distribution are obtained. The gas temperature at the disk surface shifts towards the free stream temperature, while the heat flux between the gas and surface is reduced. Stream function solutions for the flow at the disk surface are presented to demonstrate the effects of the slip boundary conditions. The torque generated by the disk is obtained with different disk rotating speed, and the gas at the disk surface has different slip velocities. [ABSTRACT FROM AUTHOR]