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This is super cool. I think it's funny how Quanta writes, "It is expected because JWST was built, in part, to find the ancient objects." "Ancient" is equivalent to "distant" because of special relativity. It's an odd thing, astronomy - it's a real world time-traveling observation, except we're limited in resolution and we can't look here only there. If it was a game mechanic I'd call it a cunning way to impose internally consistent limits on what the player can know.

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> If it was a game mechanic I'd call it a cunning way to impose internally consistent limits on what the player can know.

But if you assume it's a multi-player game, wouldn't it be easier to implement a global space-time? The reality is that you have to keep an internal clock for each player.

Partition them by velocity

Velocity relative to what?

Me. I am at the center of my observable universe :)

Relative to CMB.

If it’s a simulation then there is a fixed point. Any proper game developer would also fake it for the most part e.g. culling things the players aren’t looking at, making distant objects static billboards and they’d also fudge the numbers with something like the cosmological constant.

In practice you need a global coordinate system. For example, you'd create a "spawn point" for all players, and then, before the game starts, move them to their starting positions at a fraction of c. The game is still keeping track of units within this initial coordinate system, and transform those coordinates for the player. The reverse is done for player decisions. There is effectively an in-game "star network" that mediates between player. Each player/unit has a unique light cone associated with it.

Nothing stops us from arbitrarily designating a particular reference frame as "preferred" in a simulation; SR merely says that such a choice is truly arbitrary. Note also that this system could work recursively, such that new units must always spawn at the spacetime location of older units, and do information management (behind the scenes) in a similar way. This would turn the network into a tree - and the transforms are relatively cheap (and we could use a Spacetime algebra library!)

Note that I don't think this works for a traditional RTS like C&C or Supreme Commander. But rather a game like Civilization, but galaxy spanning (and spanning very long periods of time), where the smallest objects are something like "suns" and "fleets". The individual lives of humans would come and go as these vast battles took place over thousands of years. You'd only need to add magic like a 1g constant acceleration drive - and a strong rule against using this to directly kill planets - and assume that the fleets are actually large-ish asteroids fitted with the drives and a human and/or robotic crew.

The spawn point would then be, fittingly, Sol.

I’d play this

> The reality is that you have to keep an internal clock for each player.

You can transform between two players clocks easily enough. Time is just another coordinate to maintain.

https://en.wikipedia.org/wiki/Lorentz_transformation

> "Ancient" is equivalent to "distant" because of special relativity.

You don't need special relativity for that, all you need is a finite speed of light - a fact which was known before special relativity was developed.

> Ancient" is equivalent to "distant" because of special relativity

This is from the finite speed of light, not special relativity [1]. Light is very slow, compared to these distances. Heck, it's slow compared to distances in our solar system, taking 8 minutes for the Sun's light to hit us.

[1] https://www.wtamu.edu/~cbaird/sq/2014/10/23/how-does-looking...

> internally consistent limits on what the player can know

Interesting thought. Can you expand? What do you mean by this?

Not the original author but my first interpretation is that this means, if it were in a video game, it would be a way to self-reinforce "fog of war" where you can only have extremely local information and you don't want extra information to leak to the players.

Has anyone re-written a classic RTSG with a slower speed of light? Like, Red Alert, but with time dilation.

Not to my knowledge, but there is a game called A Slower Speed of Light, which probably needs no further clarification.

https://en.m.wikipedia.org/wiki/A_Slower_Speed_of_Light

Wouldn't that be incredibly hard, considering that the players perspective is disconnected from the units?

I observe my base and order a group of units to go to some place on the minimap. I see them moving along on their way, and decide to scroll to them. Only to realize that they already arrived and got massacred by the enemy. I go back to my base only to realize that it was destroyed ages ago (in its frame of reference) and I'm dead. Game over. Thanks for playing SR Red Alert.

In ordinary strategies you already have an assumption of immediate information transfer from unit to player - you see what each unit is seeing. This can be kept so you will see you units moving in real time but as things get further from your units on the map, the older info about them you get.

That's interesting. Wouldn't it lead to paradoxes where enemy units are shown at multiple places at once, observed from different frames of reference? Would be incredibly confusing, but confusing games can be fun too.

EDIT: Also if a unit traveled close to C away from a friendly unit, and then back, whos reference is real?

Observations merging is interesting question. Simplest thing to do may be to show enemy unit as it is seen by our unit closest to them (here we just use "real" distance in internal game's coordinates). In other words, Voronoi diagram is built with our units as seeds, and enemies are shown as seen from their cell center. This would evade enemy "phantoms" but enemies can suddenly "teleport" as they move closer to other friendly unit (or can't they? I don't really know).

In lore it may be explained like "our units know distances to objects and choose closest one among all units" since we already use "units can communicate instantly" magic.

Would be great as an artistic project, maybe not as a game.

Also in time I bet some players would find ways to win reliably, creating a new field of military strategy.

You’d have to have a HQ relative to which all dilation is calculated. If done correctly, it could simplify server operations since the need for simultaneity is relaxed.

I don't know about an RTSG, but I have seen it in a novel: Redshift Rendezvous.

Wouldn't it be slightly easier to just, you know, visually obscure the opponent's base?

Sure. I expanded in another comment: https://news.ycombinator.com/item?id=37128472

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