In the first book of the Moon Stealer series, Sir Edgar and the children use the Silver Bough to open a portal into another world. This may seem a little far-fetched, but even in reality there have been reports of gateways through to other worlds.
There have been numerous reports of portals into other worlds, some closely linked to the Arthurian legend. BroceliandeForest in Brittany, for example, where Merlin advised King Arthur over the Holy Grail, is believed to be one such portal. Even Stonehenge, which has been mentioned as another possible location for Camelot, was also thought to be a gateway. There have been several reports of people entering another world within the mountains of Pech de Bugarach near Bugarach, in the south of France, as well as the nearby ruined chateau of Miglos.
If portals that lead to other worlds could exist, then the existence of other worlds themselves would also need to be possible. The ‘Many worlds’ theory has been scientifically explored in the form of alternative histories, as mentioned by Hugh Everett in 1957, then later by Bryce Seligman DeWitt. These alternative histories are viewed like a many branched tree where every possible outcome from our past happened in another universe, leading to an infinite number of universes.
There has also been the idea that our world runs parallel to another and that we cross an endless number of other worlds. At some of the crossing lines our worlds collide and can accidentally penetrate each other.
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