The complicating factor here is that all trips to Narnia end not with the travelers returning of their own volition, but with Aslan directly intervening. Either he manages the transport himself (MN, PC, VDT, SC) or he mucks around with a pre-existing transport method (he was clearly trying to get an appropriate set of children into Narnia via the wardrobe, and then de-ages the Pevensies on their way home). So the nearly instantaneous nature of those adventures strikes me as his active choice rather than a hard and fast rule.
Actually, at least one trip to and from Narnia has a slight but undeniable canonical duration. On Lucy's second visit to Tumnus, Edmund sees her enter the wardrobe but doesn't see her immediately step back out; time passes while he walks over to the wardrobe and decides to enter himself, during which interval Lucy remains in Narnia. In fact, that trip could have lasted several minutes altogether, because Lucy and Edmund have to go hunt down Susan and Peter (who are still playing hide-and-seek) to tell them about their adventures. There is no way of telling how much of Peter and Susan's experienced duration happened while their sibling were in Narnia, and how much happened once they returned.
Also, so far as I can tell, Lewis never specifies how long Polly and Digory's trip to Charn takes from an Earth-based perspective. Digory and Uncle Andrew get several minutes to talk after Polly vanishes to the Wood and before Digory uses his own Ring, but the length of Digory's own absence is never specified. When they return with Jadis in tow, all Lewis says is, "In a moment they found themselves in Uncle Andrew's study; and there was Uncle Andrew himself, staring at the wonderful creature that Digory had brought back from beyond the world." Digory could have been gone anywhere from a second to half an hour (but not too much longer, or Polly would have missed her dinner entirely instead of merely being late). We just don't know.
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Date: 2016-07-05 07:15 pm (UTC)Actually, at least one trip to and from Narnia has a slight but undeniable canonical duration. On Lucy's second visit to Tumnus, Edmund sees her enter the wardrobe but doesn't see her immediately step back out; time passes while he walks over to the wardrobe and decides to enter himself, during which interval Lucy remains in Narnia. In fact, that trip could have lasted several minutes altogether, because Lucy and Edmund have to go hunt down Susan and Peter (who are still playing hide-and-seek) to tell them about their adventures. There is no way of telling how much of Peter and Susan's experienced duration happened while their sibling were in Narnia, and how much happened once they returned.
Also, so far as I can tell, Lewis never specifies how long Polly and Digory's trip to Charn takes from an Earth-based perspective. Digory and Uncle Andrew get several minutes to talk after Polly vanishes to the Wood and before Digory uses his own Ring, but the length of Digory's own absence is never specified. When they return with Jadis in tow, all Lewis says is, "In a moment they found themselves in Uncle Andrew's study; and there was Uncle Andrew himself, staring at the wonderful creature that Digory had brought back from beyond the world." Digory could have been gone anywhere from a second to half an hour (but not too much longer, or Polly would have missed her dinner entirely instead of merely being late). We just don't know.