I The Job of the Demon: Compressing Gas Without Work

[leafy]

TL;DR Summary

I find Maxwell's demon interesting, so I wrote my version of it. Maxwell state it in term of temperature, I wrote it in term of pressure.

Suppose we have a cylinder with one wall guard by a demon. Inside is one gas molecule moving left and right for simplicity.

Now we want to closer the wall (compress the gas) without doing work. The job of the demon is push the wall closer when the gas move left and lock the wall when the gas move right. If he close in the wall while hitting the gas, he would expend energy causing the gas to move faster and heat up.

End of the day the demon has compressed the gas without doing work. If he unlock the wall and let the gas expand, we gain energy. The gas would slow(cool) down and receive energy from the surrounding.

Of course in real life gases is number in moles so it’s impossible to find a chance where all gasses move left, but it’s possible in theory.

 

[berkeman]

How much reading have you been doing about Maxwell's Demon? In that reading, you should have found what the problem is with your setup. How much energy does the Demon expend doing this opening/closing/pushing (accelerate/decelerate) the wall? How much energy is involved in the decision making process of when to move the wall?

https://en.wikipedia.org/wiki/Maxwell's_demon

I must say that there is a common theme to many of your posts. First came Reactionless Drives, then PMMs, now this...

 

[leafy]

Yes, I'm only interest in something new. I find that the argument against Maxwell's demon is a little short. I also read Feyman's ratchet.

 

[berkeman]

Yes, I'm only interest in something new. I find that the argument against Maxwell's demon is a little short.

But if you keep posting about banned topics or topics that have been addressed here or in the simple literature (like the Wikipedia link that I posted), you are kind of wasting folks' time, no?

Please read the link I posted in detail, and if you have questions, send me a PM. For now (much like your other threads), this thread is closed.