User talk:Prevenslik

High temperatures in sonoluminescence perhaps the greatest hoax in the history of science?
The Wikepedia has reported that sonoluminescence (SL) produces high temperatures in the collapse of vapor bubbles in liquid water under ultrasoud. Indeed, temperatures from 5000 to 100 million degreees have been claimed by SL researchers. SL therefore has claimed utility by chemical processing at temperatures of 5000 degrees and nuclear fusion at temperatures of 100 million degrees.

The basis for high SL temperatures is computer simulations based on the adiabatic compression of air during bubble collapse. But the air dissolved in water cannot diffuse into the bubble prior to collapse because diffusion is very slow in relation to the time available at ultrasonic frequencies, and therefore the bubbles are only filled with water vapor. Unlike air that increases in temperature with a decrease in volume, the water vapor condenses during collapse and tends to maintain the ambient temperature of the bubble walls. Depending on the velocity, the vapor can form a non-equilbrium state that increases in temperature. But Hertz-Knudsen simulations in a collapsing bubble show that for unity condensation coefficients the bubble vapor only increases about 50 C. Thus, bubble collapse is almost isothermal.

What this means is that SL light is a form of "cold light" produced by some mechanism operating at ambient temperature.

One such mechanism is called Cavity QED induced EM Radiation whereby the IR radiation normally emitted from the atoms in the bubble surface during collapse is suppressed for bubble diameters less than the half wavelength of the IR radiaiton. In effect, the suppressed IR is trapped in the surface of the bubble and increases in frequency with the EM resonant frequency of the bubble. This is so, because to conserve EM energy the suppressed IR can only exist at the buble EM resonant frequency, and therefore the suppressed IR undergoes spontaneous frequency up-conversion as the bubble collapses through the visible to the vacuum ultraviolet (VUV). A broadband pulse of EM radiation from the IR to the VUV is produced. In the visble, water is transparent and some of the suppressed IR escapes to be directly observed as SL light. The remaining suppressed IR is up-converted to the VUV which excites chemicals or the water itself to indirectly produce spectral lines that superpose on the braodband SL spectra. All of this occurs at ambient temperature.

For details, see:

www.geocities.com/thomas_prevenslik

and press releases under:

www.geocities.com/sonoluminescence2005

Sincerely,

Thomas Prevenslik