Fair warning this is a stupid hypothetical that has little practical bearing on the game, and that pokes at weird edge cases of the magic system that are probably best answered with "it's a game, you're overthinking things". That said, if the questions are left open ended it could be useful as an ongoing experiment by an NPC Bonisagus - an interesting sounding project that never yields any definite results. Continue at your own risk.
Imagine the following scenario: we have an item, lets say a cube of metal. The cube is a greater item invested with several effects:
- A constant effect which detects if the cube is in a magic aura.
- An effect which transports the cube one pace in a fixed direction, with a linked trigger to make it happen if the cube enters a magic aura.
- An effect which transports the cube one pace in the opposite direction to the previous effect, with a linked trigger to make it happen if the cube leaves a magic aura.
All effects have unlimited uses per day.
Imagine we take this cube and walk to the edge of a magic aura.
We throw the cube gently into the aura. This triggers effect #2 which instantly transports it a pace back, across the edge of the aura.
Having left a magic aura, effect #3 is triggered. This sends the cube a pace forward again and into the aura.
This triggers effect #2, sending the cube back out of the aura... and so on ad nauseum.
- Does this experiment work as described? Does the cube actually oscillate back and forth between two positions?
- If the above is true, what is the frequency of the oscillations? This breaks down into a few smaller questions:
Is there a measurable delay in the cube sensing the aura information? The cube has been granted a supernatural sense, but in living beings there is a delay between information entering the senses and reaction - is there a similar (but usually imperceptible) delay in enchanted items?
Is there a limit to how quickly an effect can be triggered? In game terms this is probably limited to once per round - but is this actually a fundamental limit of magic, or just a game convention? Perhaps an atom of time is this fundamental limit (defined as 1/564th of a moment, which itself is 1/40th of a solar hour, or 15/94ths of a second) as this was considered to be the smallest subdivision of time in the 13th century.
Is "instantaneous" transportation actually instantaneous? Or like the sensing is it simply so fast as to be usually imperceptible?
Perhaps more importantly: If the idea works, is there a practical application?