Sandbox Discussions

[jalapeno_dude]

She quickly verified that the equations were the same often enough that it was very unlikely there would be any actual differences, she just wanted a bit more confirmatory evidence that this was the same universe and mostly expects that most variations in cosmological constants would probably end up with vastly different universes.

Oh, sure, it's just that "checking the equations were the same" is a highly nontrivial task. E.g. both of these are different ways to write Maxwell's equations:
The only symbols they have in common are '0', 'J', and '=' (and the 0 and J mean different things in the two equations!). Showing that they're the same is an involved task which requires actually understanding the definitions of all of the symbols, which would take a lot of time to unpack even knowing the concepts you're looking for. And this is an 'easy' example because I picked two versions which are valid in the same regime and are actually written with the same number of equations; I could have picked the QED Lagrangian or the four integral form equations, or even just written out the components of the vectors separately, and it would need even more unpacking.

[DanielH]

I have seen 1-, 2-, 4-, and 8-equation forms of Maxwell’s Equations, and could easily construct versions with other numbers, all of which convey exactly the same information. We believe we have those equations correct, but in the standard four-equation vesrion one of the equations says “there are no magnetic monopoles”; as I understand it, we have no strong reason to believe this but we also have no strong reason to disbelieve it and have never observed any, so just assume it. If we were wrong about magnetic monopoles not existing, or even if the Amentans decided to write their equations with the opposite assumption, they would not match up even if physics were exactly the same.

This isn’t even counting the fact that five Amentan years ago their top physicists found a convincing version of quantum gravity and they since have some corroborating empirical evidence, or that they never discovered any trans-uranic elements.

I doubt you could fully verify the physics was the same in one night even if you had a Feanaro from each world together and told them that the only things they were allowed to talk about, even while learning their respective lamguages, were the laws of physics.

Even given all of that, I imagine you could notice some things relatively quickly. Is there an abundance of inverse-square laws, including for gravitational and electromagneric forces (easy to check because the language might have a natural way of saying “inverse-square law” and SummaryBank has examples)? Can things go faster than the speed of light (we sure hope so because BABIES! but maybe not)? Are there black holes (which wouldn’t work the same way at all without almost the same general relativity, I think)?

[pedromvilar]

Do you even need anything more than the Schrödinger Equation and the Einstein Field Equations and maybe some QFT stuff to have a reasonable idea that it's the same possibly modulo constants?

[DanielH]

Sure. On Earth, Schrödinger’s equation is at least partially (maybe fully?) superseded by the Dirac equation, and the Amentans have instead been basing all their studies on Fermi’s path integral formulation.

And that’s all assuming that we have the same understanding of physics. From information we have elsewhere we know they have at least special relativity and at least some breakthroughs in QM analogous to the Dirac equation (which was the first theoretical hint of antimatter), in a different timeline and several Amentan years in the future. Looking at only the cutting edge of modern physics will work only if they are at the same point or they are beyond us in such a way that they passed through that point, but it won’t tell you anything if they haven’t advanced beyond Maxwell’s Equatins.

[pedromvilar]

*handwave handwave*

[jalapeno_dude]

*handwave handwave*

Right, this is a totally expected convention especially in the Star Trek-based Humans with Funny Hats worlds that Amenta is one of. Please don't take it as a criticism of you or lintamande, just amused me!

(On a related note, Ursula Le Guin's The Dispossessed is about, among other things, two societies with completely different and at first sight incompatible formulations of general relativity! And Ted Chiang's "Story of Your Life", which the movie Arrival is based on and which Alicorn has written fanfic of, features an alien civilization where physics is understood entirely through action principles rather than forces.)

[futurevision]

Is it mean of me to want all of Cor's Maitimo's plans to fall apart and for him to lose everything he wants. Everyone would be so unhappy. Except Eru. Eru would probably be having a great time.

[DanielH]

I expect what actually happens is, in the foolowing order:

1. Maitimo begins reforming, at Elf pace
2. Cor wins the war
3. Maitimo lets Findekano leave, at least temporarily, and lies about the reason to Cor
4. Cor finds out the truth somehow, but by then Maitimo is mostly or completely reformed

-------

Whether or not this prediction pans out, I hope some of Maitimo’s plans don’t fall apart. In particular, I want Melkor to lose and ai want his subjects to prosper.

[BlueSkySprite]

Is the Great Mage Ea-nasir in foundations of the earth an alt of the dishonest merchant Ea-nasir in our world?

[DanielH]

Unless there is more information available than I know about, that seems to be jumping to conclusions a bit about the Ea-nasir in our world. One letter of complaint without a known resolution is not very much evidence.