Position of the molecule:

Tap to measure the position of the molecule.

Erase position information

            Wrong side:        wait a little longer.

RIGHT

Entropy from erasure

Tap to measure the position of the molecule.

ERASE

swipe left

LEFT

The molecule is  on the left side: slide the piston inside  without resistance from  the molecule.

Let the molecule push the piston.

Net result:work done on the piston.

Molecule

Paradox resolved! We produce useful work by extracting heat from the molecule. However, we need to erase the information about the position of the molecule in order to return to the initial state. This generates entropy, which saves the Second Law of thermodynamics.

Reset the experiment.