A limit, where science has exhausted the interesting and useful things that can be done in a given field of study or technology. It is when further creative efforts begin producing mostly garbage, that the garbage horizon is reached. This reaching of the garbage horizon is the telltale sign that a field has matured, and that science is running out of useful new things to do in it. Like an event horizon, the garbage horizon is a boundary littered with spiraling trash, and from which no light escapes.
A patent search on engines reveals machines that have no clearly drawn means of extracting the heat and work, machines that are extraordinarily "busy" and probably don't work, and machines that have extraordinarily high contact pressures and would probably wear out very quickly when used, if they work at all. Most of this work is garbage. The rest is textbook stuff, the implementation of which is a matter of copy and paste, not the subject of new research. Hence, one concludes that the field of engines has reached a "Garbage Horizon".
by Stimpleton J Cat February 28, 2013