Randomization is the only hope here. Your solution needs to be sufficiently hard that you yourself cannot ex-post figure out where they are, so that the hero cannot either.
I would normally suggest throwing the horcrux across a horizon (black hole or outside the future light cone). But in a world with time travel and apparition that doesn’t seem quite so safe. I would weight the distribution more in the direction of space, leaving the ‘air’ ones out altogether.
If possible I would make the acceleration factor on the space bound item vary based on quantum effects at regular intervals, leaving it thoroughly distributed across an ever expanding part of the universe.
It matters somewhat just what the device being hidden is made of and whether it can, say, resist insane tidal forces, supernovae and the like. The flying item may need to be programmed to avoid such things or perhaps dive right in, depending on the specifics.
The other thing to consider is that obscurity isn’t the only way to make something inaccessible. Even if the direction is guessable, spending sufficient effort in making the item accelerate into space could make it extremely hard to find. If you can charm the item to accelerate at 10g away from the earth forever and also manage to prevent anyone from chasing after it for 10 years then you have made your horcrux damn hard to catch.
Before I did any of these things, well, at least before I did it with the >=3rd horcruxes I would thoroughly research just how the horcruxes manage to make you unkillable. I would need to confirm that wherever I hid a horcrux enabled the horcrux to do its thing in a way that is useful. ie. I don’t want to respawn inside black holes, outside the light cone of everything I hold dear or even inside any volcanoes.
I would normally suggest throwing the horcrux across a horizon (black hole or outside the future light cone). But in a world with time travel and apparition that doesn’t seem quite so safe. I would weight the distribution more in the direction of space, leaving the ‘air’ ones out altogether.
If possible I would make the acceleration factor on the space bound item vary based on quantum effects at regular intervals, leaving it thoroughly distributed across an ever expanding part of the universe.
It matters somewhat just what the device being hidden is made of and whether it can, say, resist insane tidal forces, supernovae and the like. The flying item may need to be programmed to avoid such things or perhaps dive right in, depending on the specifics.
The other thing to consider is that obscurity isn’t the only way to make something inaccessible. Even if the direction is guessable, spending sufficient effort in making the item accelerate into space could make it extremely hard to find. If you can charm the item to accelerate at 10g away from the earth forever and also manage to prevent anyone from chasing after it for 10 years then you have made your horcrux damn hard to catch.
Before I did any of these things, well, at least before I did it with the >=3rd horcruxes I would thoroughly research just how the horcruxes manage to make you unkillable. I would need to confirm that wherever I hid a horcrux enabled the horcrux to do its thing in a way that is useful. ie. I don’t want to respawn inside black holes, outside the light cone of everything I hold dear or even inside any volcanoes.