Instead of writing something new today I came up with an interactive illustration of some of my ideas from last time. Specifically I wrote a Java Applet that “simulates” (in a very loose sense) a gas, which obeys laws that are deterministic and symmetric in time. You can play around with it and see how an unlikely state becomes more and more likely ones, and see how time can be “rewound” in such a system. For a really cool effect let two gasses mix in one direction of time and then reverse the direction of time and watch them separate themselves as if by magic. And no I didn’t “cheat” to calculate the next state only the information displayed is used, I’m not keeping a record of past states to create the rewind effect.
Now the downside: wordpress won’t let me put the applet into my post directly, nor will it allow me to attach a .zip file, So, I have uploaded a “.txt” file. To make it work you need to change the extension to .zip, extract the contents, and then open the entropy.html file. If you have problems getting the file or extracting it please let me know so that I can try to fix things. If anyone could host and run the applet (with a link pointing back to yesterday’s post) I would be most grateful.
And if anyone wants the source code I can provide that too.
UPDATE: Fixed an error in the original applet. Please redownload.
UPDATE: See it online here.