/sci/ - Science & Math

>>12745895
Elon tweeted last night that your mom was a disappointing lay.

>>12718247
>"Okay we have a question from a viewer here: Why is Mars red? Well ah, who wants to take that one?"

>>7490492
>There does seem to have been a lot of confusion caused by this article, possibly because some of its content was incorrect. In the original Science article, the authors explained quite lucidly what they had achieved and justified their claims with correct thermodynamic arguments. Unfortunately, in this piece by Zeeya Merali, she made the grave error of claiming the researchers had achieved temperatures below absolute zero. This was simply untrue as the original paper showed. Temperatures below absolute zero are simply not possible; achieving them would necessitate violating both the Second and Third Laws of Thermodynamics. No; odd as it may seem, due to the definition of temperature, negative temperatures are hotter than positive temperatures. This has been well known and accepted since the pioneering work of Purcell, Pound and Ramsey in the 1950's. My authority for making these claims follows from a lifetime of work in thermodynamics with a particular interest in the laws and their interconnections, as well as an examination of negative temperatures and their place in Carnot cycles.

>Correcting most previous authors (because they are wrong), the issue here is fairly well explained in the wikipedia article on the subject . Essentially negative temperature here refers to a thermodynamic property of the system that is perhaps divergent from the ordinary definition in this case. Temperature here defines the rate at which entropy increases as thermal energy is added to the system. Ergo, negative temperature relates to a state where adding energy at least incrementally might decrease the entropy of the system. Negative temperature is not exactly new, the originality of this research relates to the relatively macroscopic nature of the negative temperature system. The lede of this article needs to be read with this emphasis in mind.