Mirror, mirror

(NOTE: This is an old post from February 23, 2007 that mysteriously dissapeared when I upgraded to the new version of Blogger. Exhumed from the Google cache.)

This post on Centauri Dreams describes an extremely interesting propulsion technology called "Photonic Laser Thrusters". It works by bouncing photons betweeen two confronted mirrors thousands of times, so that the mirrors are pulled apart by radiation pressure.

It reminded me of a rather more fanciful method of transport involving confronted mirrors, imagined by Gene Wolfe in The Shadow of the Torturer:

Father Inire drew the wall of the octagon closed behind them. It was a mirror in which she could see his face and his arm and shining infinite robes reflected. Her own form too [...] but there seemed to be another girl -her own face peering over her shoulder; then another and another and another, each with a smaller face behind it. And so on ad infinitum, an endless chain of fainter Domnina-faces.

She realized when she saw them that the hall of the octogonal enclosure through which she had pased faced another mirror. The light of the blue-light lamp was caught by them all and reflected from one to another as boys might pass silver balls, interlacing and intertwining in an interminable dance.

A bit of technobabble follows, explaining how the mirrors work as a teletransporter (there's also a homage to Borges). Quite enchanting, really; though I hope the theory behind the "Photonic Laser Thrusters" is a bit more solid...