The trinity knot: It is found on Celtic ornaments, Germanic rune stones, Japanese illustrations, and in Christian imagery. There is no beginning and no end – everything is interconnected.
Similar to the Triquetra, the passage in the caves creates a closed time loop between the years 1953, 1986, und 2019, ensuring the past affects the future and the future influences the past. The principle of cause and effect no longer holds true.
The Triquetra is of significant symbolic value to the time travelers. It is depicted on the cave's metal door, the leather notebook, and in the Stranger's drawings – plus, it's part of the Emerald Tablet.