<story><title>Maxwell’s Demon Continues to Startle Scientists</title><url>https://nautil.us/blog/how-maxwells-demon-continues-to-startle-scientists</url></story><parent_chain><item><author>scrooched_moose</author><text>Possessing only an undergrad level of physics, I&amp;#x27;ve never understood why this is a remotely interesting question.&lt;p&gt;It seems to effectively be equivalent to &amp;quot;Imagine we have a refrigerator with a massless, frictionless motor that also doesn&amp;#x27;t need to be plugged in. Isn&amp;#x27;t it crazy that this refrigerator would violate the second law of thermodynamics?&amp;quot;</text></item></parent_chain><comment><author>ineptech</author><text>A motor that doesn&amp;#x27;t require energy violates the second law by definition; a selectively-enforced barrier that lets hot particles through but not cold particles didn&amp;#x27;t obviously provably cost energy.&lt;p&gt;If that sounds like a cop out, remember that the Demon is a metaphor that&amp;#x27;s supposed to represent an as-yet-undiscovered technology.  Like, instead of a literal massless door that opens and closes, something like, &amp;quot;What if we discovered a clever way of designing a little gap between two chambers and ionizing the particles such that only hot ones go through.&amp;quot;</text></comment>
<story><title>Maxwell’s Demon Continues to Startle Scientists</title><url>https://nautil.us/blog/how-maxwells-demon-continues-to-startle-scientists</url></story><parent_chain><item><author>scrooched_moose</author><text>Possessing only an undergrad level of physics, I&amp;#x27;ve never understood why this is a remotely interesting question.&lt;p&gt;It seems to effectively be equivalent to &amp;quot;Imagine we have a refrigerator with a massless, frictionless motor that also doesn&amp;#x27;t need to be plugged in. Isn&amp;#x27;t it crazy that this refrigerator would violate the second law of thermodynamics?&amp;quot;</text></item></parent_chain><comment><author>hedora</author><text>Imagine the door had some mass and some friction, but the particles were really heavy, so even a few correct openings could create a large energy imbalance.&lt;p&gt;There’s no apparent relationship to the energy gain per separated particle and the energy used by the door.  That makes it hard to prove it’s not generating energy.&lt;p&gt;That’s what makes it an interesting problem.</text></comment>