The temperature for the next week is not supposed to get over freezing (32 degrees F. / 0 degrees C.). Living in northern Utah means that you'll have weeks like this from time to time - often several times in the same month. I know it's not as cold as many other places, nor is it the coldest we can get. Peter Sinks (not far from where I went to college in Logan) holds the state record (or at least did) at -69 degrees F (-56 degrees C). It has a bit of an unusual situation that fosters that kind of temperature. I do remember being on campus when it was -40 degrees F/C (the point where the scales intersect). That day it didn't get above 0 degrees F (-17 degrees C.) You know that it's below 0 degrees F when the air in your nose freezes and pulls all of your nose hairs. If you've never experienced it you'll understand when it happens.
It's interesting that cold is measure of how little heat there is in something. A degree is a measure of heat. That's why the absolute scale (Kelvin) is considered such. Fahrenheit and Celsius are taken in reference to something. Fahrenheit has its zero point centered on a equal mixture of water, ice, and salt. Celsius uses zero as the freezing point of water. Kelvin uses the same degree size as Celsius but has zero at the point that all matter becomes inert. According to the third rule of Thermodynamics you cannot reach absolute zero. If you think about it this is simple and a bit of a no brainer. In order to measure something your instrument needs to move. If you're at absolute zero nothing is moving. A metaphor that Pratchett likes to use may be fitting. Reaching absolute zero is like trying to open a box with the crowbar that is inside of it. It just isn't going to work unless the laws of physics decide to conveniently ignore you. However, near zero temperatures are a big area of study. It's even used in quantum computers. Derek from Veritasium did a video with with Dr. Morello from the University of New Wales where they talk about one of the methods of cooling thing to near absolute zero using helium
So if we consider the absolute scale as the measure of heat that means that we cannot have negative temperatures because there is nothing less than nothing. However, there are studies that work in "negative temperature." It is not less heat that zero, but rather a different level of energy. Professor Moriarty from the University of Nottingham explains how this work, but not without a little frustration when Brady asks him to make his metaphor fit an incompatible situation.
You can get some answers to frequently asked questions about negative absolute temperatures here. In all, it's fascinating how cold we can get something and the consequences of doing so. Or should I say, how much heat we can suck out of it.
It's interesting that cold is measure of how little heat there is in something. A degree is a measure of heat. That's why the absolute scale (Kelvin) is considered such. Fahrenheit and Celsius are taken in reference to something. Fahrenheit has its zero point centered on a equal mixture of water, ice, and salt. Celsius uses zero as the freezing point of water. Kelvin uses the same degree size as Celsius but has zero at the point that all matter becomes inert. According to the third rule of Thermodynamics you cannot reach absolute zero. If you think about it this is simple and a bit of a no brainer. In order to measure something your instrument needs to move. If you're at absolute zero nothing is moving. A metaphor that Pratchett likes to use may be fitting. Reaching absolute zero is like trying to open a box with the crowbar that is inside of it. It just isn't going to work unless the laws of physics decide to conveniently ignore you. However, near zero temperatures are a big area of study. It's even used in quantum computers. Derek from Veritasium did a video with with Dr. Morello from the University of New Wales where they talk about one of the methods of cooling thing to near absolute zero using helium
So if we consider the absolute scale as the measure of heat that means that we cannot have negative temperatures because there is nothing less than nothing. However, there are studies that work in "negative temperature." It is not less heat that zero, but rather a different level of energy. Professor Moriarty from the University of Nottingham explains how this work, but not without a little frustration when Brady asks him to make his metaphor fit an incompatible situation.
You can get some answers to frequently asked questions about negative absolute temperatures here. In all, it's fascinating how cold we can get something and the consequences of doing so. Or should I say, how much heat we can suck out of it.
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