Bob Shaw’s singular contribution to science fiction came in small packages. Shaw wrote many short stories (one, "Light of Other Days", is included in last year's Science Fiction 101, in print and Kindle), and a novel, Other Days, Other Eyes (alas, unavailable for Kindle), using this speculative technology. But these stories were no more about slow glass than Albert Camus’ The Plague (La Peste) is about Yersinia pestis.
The Technovelgy entry for slow glass gives a brief description of the “Bose-Einstein condensate” that forms slow glass, and its critical property:
Bose-Einstein condensates are created when atoms are cooled to absolute zero; the atoms collapse into the lowest quantum state, producing a superfluid…
Bose-Einstein condensates have optical densities such that the speed of light passing through the mass is extremely low—walking speed as opposed to its usual 186,000 miles per second.
From that concept, Shaw built a amazing sub-genre of “what-if” speculation. One story has a murder "witnessed" by slow glass; some years later it will divulge the shocking truth. When it does, will the murderer be the same person he once was, or will his long contemplation of the inevitable revelation have changed him?
Another tale dwells briefly on the contented married life of a man in the country, as seen by passers-by and brief visitors. But inside the cottage, a very different state of life is hidden by the outward display supplied by the slow glass. Superficially this is simply poignant, but underneath lies an allegory of the occult nature of every marriage.
The light that passed through Shaw’s slow glass illuminated (eventually) many facets of the human condition. What more ought we to ask of fiction, science or otherwise?