On Sat, Jan 12, 2013 at 5:14 PM, Dave Long <[email protected]> wrote:
> Another metaphor for temperature: there are two basic "currencies" in > physics, entropy and energy. If you have an ordered state, you can usually > easily trade it for a less-ordered state, and if you have an energetic > state, you can usually easily trade it for a less-energetic state. > Temperature is the "exchange rate" between these two currencies. At low > temperatures, energy is dear and order cheap, so we wind up with systems > whose parts are predictably in one of their lowest energy states. At high > temperatures, order is dear and energy is cheap, so we wind up with systems > whose parts are unpredictable, as likely to be in arbitrarily high-energy > states as lower ones. > Nice. > A negative temperature is then the equivalent of a negative exchange rate > -- which is why it takes some effort to set up*, as the universe usually > conspires to quickly arbitrage such situations away. > I am not sure the analogy reads well here. What is a 'negative exchange rate' in the real world except as a convention denoting 'inverse'?
