Spectrophobia Spectrophobia Spectrophobia (from Latin: "spectrum", n. specio, an appearance, form, image of a thing; an apparition, spectre) or catoptrophobia (from Greek κάτοπτρον "kátoptron", "mirror") is a kind of specific phobia involving a morbid fear of mirrors, sometimes related to the fear of ghosts or the undead. This phobia is distinct from eisoptrophobia, which is the fear of one's own reflection. Generally, an individual that deals with spectrophobia has been traumatized in an event where they believe they have seen or heard apparitions or ghosts. The individual could also become traumatized by horror films, television shows, or by nightmares. This fear
Irrational number is not closed, the induced metric is not complete. However, being a G-delta set—i.e., a countable intersection of open subsets—in a complete metric space, the space of irrationals is completely metrizable: that is, there is a metric on the irrationals inducing the same topology as the restriction of the Euclidean metric, but with respect to which the irrationals are complete. One can see this without knowing the aforementioned fact about G-delta sets: the continued fraction expansion of an irrational number defines a homeomorphism from the space of irrationals to the space of all sequences of positive integers, which is easily