The universe is a collection of implementations of symbols within ξ. That is to say, if ξ offers the blueprints to allow something to exist, the universe is where that existence can actually happen. This understanding of the universe does not assume any inherent properties about it. Rather, any rules that exist in the universe are ones that also symbolically exist in ξ, and have been allowed to manifest. As such, variations on the universe using a different rule set could exist, and be modifying the pool of ξ just as our universe does. Due to the nature of ξ being itself a set of symbols shared by multiple hypothetical implementations that are capable of modifying it, if such variants on the universe exist, it would be constantly affecting the available symbols in ξ that are at our universe's disposal just as we would be modifying the available symbols for that universe.
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