quantum measurement
jhalper | January 1, 2014A recent paper by Weizmann Institute scientists suggests that we might be able to break the third law of thermodynamics. This is how that law was originally formulated in 1908 by Walther Nernst: “It is impossible for any procedure to lead to the isotherm T = 0 in a finite number of steps,” (source: Wikipedia). To elaborate, the entropy of a system approaches nil as the temperature closes in on absolute zero, so that extracting further energy becomes increasingly difficult. According to the third law, you can get very close – temperatures of less than a billionth of a degree have already been…
jhalper | May 24, 2011This week's Weizmann news stories: A "steam release valve" for inflammation, a "brake" for cell division and an "amplifier" for quantum signals.
The steam release valve mechanism also involves an amplifier - one that ramps up the inflammation signal in response to viral attack on a cell. When the signal reaches its peak, it trips a nearby protein called caspase-8, which then kills the amps, damping the signal back down. The scientists think that failures in this mechanism could be behind various inflammatory diseases.
The brake on cell division turns out to be our old friend p53. Thirty…
drorzel | August 2, 2010Thoreau at Unqualified Offerings gets credit for inspiring two posts today with his proposed Murphy's Law experiment and this one, about an unrelated issue in quantum measurement. This is an analogy suggested by a colleague a couple of years ago, comparing the projection of a quantum wavefunction in the measurement process to the lottery.
The classic example of this problem is something like the double slit experiment with single particles. You have some position-sensitive detector that we can imagine as being made up of a large number of pixels, each having some probability of detecting a…