Sci-fi RPGs: time dilation from space travel and gravity

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Necrozius

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Do any science fiction RPGs include a game-able way to include time dilation?

Example: time as a resource contextually from the PCs home planet (ie, 1 hour of near-light speed travel = 1 year on Earth or something).

I would like to tap into this for PC drama. Do they take that short-cut to get to their destination before the space pirates, even though it goes near a super massive Black hole?

Obviously not going for perfect astrophysics here, just a drama system to keep track of time as a resource during interstellar travel.
 

Moonglum

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A good question. I think it is a really interesting idea, but suspect the outcome would be a kind of extreme roleplaying situation, where a traveling party would experience every place they visit as a strange new experience, and be seen by it as bizarre outsiders, simply because vast reaches of time will have passed while they travelled. It could be a really fascinating way to run a campaign if you did it right, but you would need to throw away many familiar concepts about how PCs relate to settings.

If you committed to the idea, the way it would be expressed would be really extreme - if you travel fast enough to avoid dying of old age on your way to the nearest star, many thousands of years will have passed in 'uncontracted' reference frames.
 

Necrozius

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Yeah there would have to be some "handwavium" going on to get this to work.

For my upcoming campaign, it's very Star Trek Voyager esque. The PCs are scientific explorers in an unknown sector. Every planet is new to them.

But I like the idea that there's some kind of "clock" that they keep track of their time back on Earth.
 

AsenRG

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Yeah there would have to be some "handwavium" going on to get this to work.

For my upcoming campaign, it's very Star Trek Voyager esque. The PCs are scientific explorers in an unknown sector. Every planet is new to them.

But I like the idea that there's some kind of "clock" that they keep track of their time back on Earth.
Now just ask yourself who would sign up for a scientific mission that means he returns to a place where everyone he knew has died of old age...:shade:
 

Supervisor194

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Now just ask yourself who would sign up for a scientific mission that means he returns to a place where everyone he knew has died of old age...:shade:

That dude in the Twilight Zone episode "The Long Morrow".
 

AsenRG

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That dude in the Twilight Zone episode "The Long Morrow".
Possibly. Now add to that nix someone who is suffering from an incurable slow disease and hopes science in 60 years would have the answer, the guy who feels like a total failure with good reason and wants the blank slate, and a criminal wanting to avoid prosecution on grounds of time elapsed...:devil:
 

Necrozius

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Now just ask yourself who would sign up for a scientific mission that means he returns to a place where everyone he knew has died of old age...:shade:
Yes, I've asked myself that. The mission would have to be very important for anyone to consider even going.

Which will actually and inevitably be a dilemma for humanity when the time comes for interstellar travel. But that's a whole other thing.

In terms of a roleplaying game, I'm considering TIME being another risk-factor resource for the players to manage. Just like how in other games PCs have to manage HP, supplies, food, water, air, power, sanity etc...

In a purely practical and gamist sense, do any sci fi games out there do this?
 

AsenRG

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Yes, I've asked myself that. The mission would have to be very important for anyone to consider even going.
Or his current situation might stand to be improved by the time elapsed, or it might be so bad he'd believe the only way it could change in decades elapsed would be towards improvement...:thumbsup:
 

robertsconley

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Do any science fiction RPGs include a game-able way to include time dilation?

Example: time as a resource contextually from the PCs home planet (ie, 1 hour of near-light speed travel = 1 year on Earth or something).

I would like to tap into this for PC drama. Do they take that short-cut to get to their destination before the space pirates, even though it goes near a super massive Black hole?
That wouldn't work. Because what time dilation does is speed up outside time faster than your personal time. So either way you are not beating the space pirate to the destination. Avoiding them yes by travelling faster into the future of the destination with no way back to the past.


Obviously not going for perfect astrophysics here, just a drama system to keep track of time as a resource during interstellar travel.

From the character's perspective, time dilation is a form of time-travel into the future with no way back to the past. Time dilation is measured by the tau factor. So if you went fast enough so that you only experienced 1 year while travelling to Alpha Centauri a little over 4 light years away. Then you experienced a tau factor of 4 which is around 94% of the speed of light.

Formulas are

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Necrozius

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That wouldn't work. Because what time dilation does is speed up outside time faster than your personal time. So either way you are not beating the space pirate to the destination. Avoiding them yes by travelling faster into the future of the destination with no way back to the past.
Okay, obviously that was a shitty example.

So I wouldn't use time as a risky resource in immediate threats like that, for sure.

To go back to my original question, have any sci-fi games out there toyed with this concept as a source of dramatic "resource" tracking?
 

AsenRG

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Okay, obviously that was a shitty example.

So I wouldn't use time as a risky resource in immediate threats like that, for sure.

To go back to my original question, have any sci-fi games out there toyed with this concept as a source of dramatic "resource" tracking?
Nope, you can use it.
You should just travel more slowly than the pirate, and arrive earlier than him, than use the time to actually mount a defense:grin:!
 

robertsconley

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Okay, obviously that was a shitty example.

So I wouldn't use time as a risky resource in immediate threats like that, for sure.

To go back to my original question, have any sci-fi games out there toyed with this concept as a source of dramatic "resource" tracking?
It really only comes up as a result of sub-light travel. And thanks to interstellar people are aware that it can result from being too close to a black hole.

I will say this as you saw above, the basic formula are easily computed. The logistic regardless of system is time tracking. So you could use Cepheus, the Alien RPG, Star Frontiers, whatever. You just have to make a setting based around sub-light travel or a type of FTL travel where time dilation is a factor.

You will need to keep track at a minimum the group personal time, and campaign time. While bookkeeping we are only talking about travel into the future from the character PoV. If you keep the absolute time span short then you don't have to worry about crazy world building. You are leaping days or weeks into the future instead of years, decades, or even centuries.


For example take Traveller, you can say that Jump are instantaneous from the PoV of the players, but they take a week from the view of everybody else.

With FTL travel you could even do reverse time dilation and say that Jumps take a week from the PoV of the players but are instantaneous from the view of everybody else. The more jumps you do, the faster you age relative to the rest of the world. And you can get weird side effect like the military sending a team that needs five months of training on multiple jumps and effectively "level up" instantaneously although they experienced five month of time while jumping.

Reverse time dilation not based on the real world mind you but FTL is always handwavium. I can see an empire doing that type of training, and then after it all done, send the crew to a black hole for regular time dilation so their internal clock are set back to match up with their friend. Although that means to their friends and family they would be away for five months.

Hope this helps with ideas.
 

Nobby-W

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Do any science fiction RPGs include a game-able way to include time dilation?

Example: time as a resource contextually from the PCs home planet (ie, 1 hour of near-light speed travel = 1 year on Earth or something).

I would like to tap into this for PC drama. Do they take that short-cut to get to their destination before the space pirates, even though it goes near a super massive Black hole?

Obviously not going for perfect astrophysics here, just a drama system to keep track of time as a resource during interstellar travel.

If you haven't read The Forever War, it's a book about a war that goes on for a millenium or so due to time dilation, and the story goes into the culture shock as people come home decades or centuries after they leave. It's top-tier sci-fi - one of the classics - and picked up several major gongs in its day. I re-read it just a few years ago and didn't really feel it had aged too badly.
 

arjunstc

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You will travel to a distant part of the galaxy... only to find that Earthlings a hundred years from your future who have developed a FTFTL drive that doesn't incur time dilatation have reached there before you... yesterday.
 

Moonglum

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Another great SciFi novel that relates to this general subject is Larry Niven's 'A World Out of Time'
 

Séadna

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Time dilation due to gravity and due to high relative velocity act in opposite directions, the former speeds up the external world relative to the observer, the latter slows it down.

There's also more advanced forms of spacetime distortion like frame dragging found near spinning/Kerr black holes.

I came up with a little guide to using these effects in a game which I'll tidy up and put here within the week. In my experience the sitting next to a black hole example is easier to use as the results are fixed numbers. I did an Alien megastructure dungeon above a black hole for Mothership once to good effect. Each level of the dungeon operating on a seperate clock.
 

TJS

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Another great SciFi novel that relates to this general subject is Larry Niven's 'A World Out of Time'
A Deepness in the Sky by Vernor Vinge, makes a lot of this concept to good effect as well.
 

Séadna

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O my god, the tides!
That's why if one wants to be realistic you need to set things above a supermassive blackhole so you can have large time dilation without large tidal forces.
Otherwise it can just be alien superscience material holding the station together.

I was inspired by the civilization living above a black hole in Kip Thorne's old popular science book "Black Holes and Time Warps" and the Mosdva living above a Red SuperGiant in Peter F. Hamilton's "The Naked God".
 

AsenRG

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That's why if one wants to be realistic you need to set things above a supermassive blackhole so you can have large time dilation without large tidal forces.
Or you can have a world where people only live in the mountains to avoid the regular tsunamis sweeping the plains...:devil:
 

Agemegos

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That's why if one wants to be realistic you need to set things above a supermassive blackhole so you can have large time dilation without large tidal forces.
Yes, but the low tidal gradient means that the time dilation factor doesn't vary noticeably with altitude over the ranges involved. And alien superscience won't hold the people together, nor keep up the blood supply to their heads.
 

Séadna

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Yes, but the low tidal gradient means that the time dilation factor doesn't vary noticeably with altitude over the ranges involved.
I don't want to get too into this on an RPG forum, but it's easy enough to have big differences in local time without tidal forces. Time dilation falls off as 1/r, tidal forces as 1/r^3. So you can have big differences in local time between the upper and lower levels of a megastructure without tidal forces as there are distances at which time dilation is still appreciable but tidal forces aren't.

The super science comment was just a joke about using whatever handwavium one wants if one isn't interested in astrophysics but just wants a cool setting.
 
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