A clever “perpetual motion” device [video]
Steve makes an interesting statement when he says &quot;we know that perpetual motion is not possible&quot;. Yet we have a modification to the general cosmological view with the theoretical entity &quot;dark energy&quot; which if you consider what is said about it properties, it provides a means of creating a &quot;perpetual motion&quot; environment.<p>So what can we say: Does perpetual motion exist or not?