The laws of thermodynamics govern the flow of energy - from your coffee cup to the sparse plasma floating between stars to the formation of black holes.  And, in short, they are: You can't win. You can't break even. You can't get out of the game. These laws, which were first derived by dreaming of ideal heat engines, turned out to have profound and vital physical and philosophical consequences. Far from just relating to an arbitrary concept called "temperature", they can teach us about how the Universe began - and how it will all, inevitably end. This episode deals with the Third Law of Thermodynamics - regarding the impossibility of attaining absolute zero. We'll also discuss the seeming paradox that, while you cannot reduce matter to a temperature of absolute zero in a finite time, you can have negative absolute temperatures.... according to certain definitions of temperature.   You can listen to all of our archived episodes up at www.physicspodcast.com or listen to our sister podcast, Autocracy Now, at www.autocracynow.libsyn.com. On the physicspodcast website, you will find a contact form where you can discuss any comments, questions, concerns, suggestions for future show topics or interview guests - we'd love to hear from you. You can also donate to the show there, or buy some bonus episodes to help support us: we have a Patreon, or you can label your Paypal donation and I will send you the episodes. You can also contact us via Twitter @physicspod or @autocracynow. Thanks for listening, and tell fellow thermodynamic systems about the show!