[HN Gopher] Special Relativity and Middle-Earth
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Special Relativity and Middle-Earth
Author : goy
Score : 99 points
Date : 2022-12-19 08:25 UTC (14 hours ago)
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| pavo-etc wrote:
| The way this describes two treefolk seeing each other both aging
| slower is the first time I've really understood how two parties
| relativistic effects are both able to see each other aging slower
| than themselves: the points at which they are seeing each other
| are not simultaneous.
| [deleted]
| Gravityloss wrote:
| The neighbor looks like it's aging more rapidly, not slower!
| Think if the neighbor tilts away from you, in the disk-by-disk
| play it will just look moving away disk by disk, the disks are
| elongated and the disks will end earlier.
|
| And from the tilted neighbor's point of view it's similar.
|
| Maybe it's easier to first think of two trees that both tilt
| away from each other.
| pa7x1 wrote:
| The key observation is that there is no simultaneous. As in, an
| objective, observer independent, notion of simultaneous. Each
| observer carries its own notion of simultaneous and observers
| in different reference frames call different things
| simultaneous.
| hammock wrote:
| Time is relative
| ndsipa_pomu wrote:
| Fun article, but I think the connection to Middle-Earth is
| tenuous at best. I had hopes that there was going to be some
| interaction between trolls and humans, but he ends up just using
| the tree-like beings.
| 082349872349872 wrote:
| The special rel just-so story I had got was night people and
| day people, and the night people had set true N to the north
| star, while the day people used the midpoint of sunrise and
| sunset for true N, so all their cardinal directions were
| rotated relative to each other.
|
| They were then confused why their measurements of distances
| always agreed but of position always differed, until someone
| came up with the rotation equations that allowed one to map day
| to night and night to day.
|
| Change normal trigonometric rotation to hyperbolic, and you've
| got most of special rel.
| Eleison23 wrote:
| philipwhiuk wrote:
| I don't really understand why he didn't just use trolls (which,
| as he mentions don't move in the day) rather than invent a new
| tree folk.
|
| It seems like he came up with the disk idea and then thought
| 'this looks like a tree' and back-solved Middle-Earth and then
| was like 'oops, this behaviour is actually trolls' when writing
| it up (rather adjusting his paper to use stone discs)
|
| I can't imagine there's many people who both get past the opening
| and don't understand the concept sufficiently for the allegory to
| be useful.
| roenxi wrote:
| I've always liked this sort of interpretation. because it
| suggests that the entire universe might actually be a static
| object; and time itself a complete illusion.
|
| Imagine a hyper-being that has a few more dimensions, looking
| down on us as we look down on Tao's treefolk. We might
| optimistically imagine that they see our little moment of
| conscious perception moving backwards and forwards in time like a
| motivated fish. We perceive it as one way though, because when
| our little window of perception moves backwards it enters a state
| where it cannot remember the future, and when it moves forward it
| enters a state where it has no reference of lingering unevenly at
| different past times.
|
| Seems unlikely, but so does everything else.
| 082349872349872 wrote:
| Yes, and Einstein was thinking along these lines.
|
| However, he (and his successors) have had a great deal of
| trouble reconciling a static universe with quantum mechanics.
|
| (a) as far as I know, "many worlds" is the closest anyone has
| yet come
|
| (b) luckily there are very few physical problems involving
| scales that would invoke both GR and QM.
| aaron695 wrote:
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