Considering that every person has the potentiel to become a Shinigami (not that everyone will make it, but it's possible) and every shinigami has a coul cutter of his own which automatically appears when he is created, I once thought that the swords are created from the soul of the wielder.
But if you read a bit of what is said about the swords, it seems that they existed for quite a while (the grand fire sword, the two captains who use two swords each, the fact that each sword has a predetrminate name) and have an existence as physical objects (in a form of physical spiritoens, of course).
can someone explain this to me? is there a warhouse of soul cutters and whenever a shinigami is born a sword teleports from there into his hands? wouldn't that mean a shinigami could use two diffrent swords?
oh, and a seconed question, it was mentioned by rukia that the sould live in one of the quardrans in the spirit world, and since we saw her as a child, it seems that they also grow up (in an ultra slow rate), so do they die after a thousand years or so in the spirit world? cuz otherwise i would think the place will be filled with old people.