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GURPS Alternate Earths

Blue Ghost

SOC-14 5K
Knight
Has anyone ever used the Alternate Earths, or for that matter any other non Traveller, GURPS book for their gaming sessions?
 
Yes, there is a setting in Alternate Earths where you ride trains through wormholes to distant planets...

which I used.
 
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I used to like GURPS. But then later authors (by later, in this context, post 1990) ignored the foundational aspect - in GURPS, SJ's design notes include that skills are 250 hours a point, and that setting books should warp the core system, not warp the settings to fit the system.

Further, I quit GURPS entirely when SJG caved to the munchkins and started making NPC's stupidly high attribute levels.
 
I used to like GURPS. But then later authors (by later, in this context, post 1990) ignored the foundational aspect - in GURPS, SJ's design notes include that skills are 250 hours a point, and that setting books should warp the core system, not warp the settings to fit the system.

Further, I quit GURPS entirely when SJG caved to the munchkins and started making NPC's stupidly high attribute levels.

...what does this have to do with the OP?
 
I don't like GURPS point based character generation, but their task resolution /combat system isn't bad.

Other GURPS books I have used are Terradyne and the entire Transhuman Space series.

Great resources.
 
I'm a big GURPS fan. Most of the books are thoroughly researched and playtested, so even if you don't use the system you have a ton of information available you can graft onto your world(s).

Say if you have a world that is a lot like ancient Egypt - they have a setting book for it. Just sand off the serial numbers, as they say, and you have a fully realized setting. Or in the Alternate History books you can use, for example, the Reich-5 timeline for a balkanzied world dominated by fascists and dictators. Or a pocket empire actually made up of two powerful, brutal dictatorships that have coordinated to conquer their surrounding systems.

And that's the beauty of GURPS itself - you just use what you want or need. But if you want psionics, or magic, or whatever, you can add it in. Then again, point system builds for characters is complicated, it can take time to create characters. But if you're using Traveller, that doesn't apply anyway.

I know Ken Hite wrote big parts of the Alternate History worlds, and he is a great game designer. You can't go wrong with a world designed by him.

- edit; oddly enough I could not stand Terradyne. That was one of the few SJG books I felt I wasted money on. To each their own.
 
There are a lot of interesting ideas from many of their books. I find the character generation system too complicated for my aging brain.
 
Interesting. What didn't you like about Terradyne?

Its been a while so I don't recall details. I just remember disliking the setting. Then again its a very non-Traveller like setting and I was all about the Traveller at the time.

But of course just altering a few names here and there and you have a perfectly fine early stellar tech setting for a Traveller world.

I dunno - maybe it was just the really terrible artwork ;)
 
Cool.

The reason I asked is because there's so many GURPS books, and a lot of them are well researched. I bought them primarily as reference books for writing and general info. They're almost as good as encyclopedias, and have a more energetic and entertaining narrative.

I tried introducing non space-opera situations, more speculative fiction using other source material and my own imagination into my gaming sessions ... with mostly good results.

And with that in mind it struck me as odd that there wasn't more activity in the GURPS section with discussion of players somehow arriving on a "parallel Earth" or Atlantis and so forth, and hearing about tales that were a little more far ranging because of the GURPS source material. It's the kind of thing I was going to aim for when Hunter and I were first talking way back when.

But, as GypsyComet reminded me, Traveller is space-opera, and has evolved beyond proto-Travellers formulations. Still, I thought there might be more tapping of GURPS than there apparently has been.

Thanks for the replies. Most enlightening and much appreciated.
 
I feel like there are too many different fundamental technological assumptions between GURPS and Traveller to combine them, unless your game is largely focused on modern-Earth or earlier tech planets.
 
What if I were to run an Alternate Earths campaign set in the Terra System with the Traveller setting substituting for Homeline. The Third Imperium is funding parachronic research from a base on Luna, instead of parschronic projectors they have wormhole drives, which are similar to jump drives except they move sideways in time to the same system they are in but in a parallel universe.

What sort of starship would be best, scout ship or free trader. Only one starship can visit a parallel Earth at a time, because a wormhole connects two and only two universes, in their natural state they are microscopic and it takes something similar to a jump drive to stretch its mouth so a starship can pass though, the wormhole is otherwise stored in the wormhole drive when not in use.

The same starship can visit more than one universe, but must first pay a visit to the Luna research base to swap wormholes, each drive can only hold one wormhole at a time.

All the Alternate Earths from the two Alternate Earths GURPS world books have wormholes stored at the Luna Research base, in addition there are wormholes connecting to the Interstellar Wars, the New Era, and to Twilight 2000, 2300 AD, GURPS Middle Ages, Homeline, and a Ringworld alternate set about one million years in the future, since only one starship can visit each universe at a time, the Imperium has a policy of keeping a low profile. Imperium Agents have met Homeline Agents, and have had some rather unfriendly encounters with Centrum.
 
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The jump line for the Ringworld is 140 million kilometers, or 87.4 million miles from the Sun, the ringworld radius is 150 million kilometers or 93 million miles, it is 1.6 million kilometers wide or 1 million miles, and it completes a rotation around the the Sun every 9 days. The year was approximated by examining the cosmic background radiation, which is a fraction of a degree cooler, in addition some nearby galaxies have been identified, the Andromeda galaxy is slightly closer and rotate some being consistent with this universe being one million years in the future from the OTU.

The Sun appears to be Sol, its spectral type matches what would be expected 1 million years in the future, all the planets in the Solar System have been cleared out, all that remains are some Oort cloud objects, presumably the materials of the planets went into construction of the Ringworld. At the approximate radius of Mercury's orbit are 10 shadow squares, each one spanning one twentieth of the circumference of its orbit for every complete totation of the Ringworld around the Sun, the shadow squares make one tenth of a rotation around the sun, thus every nine days a region of the Ringworld passes over nine shadow squares creating equal periods of day and night 12 hours long.

There are two rim walls 1000 miles high holding in the ringworlds atmosphere by centrifugal force and preventing it from spilling over the sides. Docked to the rimwalls are an enormous number of bursary ramjets, these are huge starships, each one is about 10 miles long.

There is no sign of artificial gravity anywhere along the ringworld. The landscape of the ringworld is about 50% ocean with two great oceans on opposite sides of the ringworld for balance, in one of the oceans is a map of the Earth, it is a polyhedral projection centered on the north pole with the oceans between the continents stretched but the shapes and areas of the continents being preserved. The continent of Antarctica is positioned off the southern tip of South America, its shap and area preserved. The polar regions of this 1:1 scale map of Earth are actively cooled by radiators underneath the floor of the Ringworld creating a polar climate. The average temperature of the Ringworld's surface is 72°F, there are local seasonal variations caused by active cooling under the floors of various regions while other parts remain tropical all year round. All of the local seasonal cycles are 365 days long and are not synchronized. In some places its autumn, other places. Its winter, spring, or summer.
 
I think the best starship to send to Ringworld, would be a mercenary cruiser. The Imperium would be interested in a number of things, one likely place to start would be the Earth map, it is apparent that the builders of the Ringworld came from Earth. There is not much traffic going to and from the Ringworld, there is indecipherable radio noise coming from various parts of the ringworld, parts seem neglected and not well maintained. The civilization which built the Ringworld seems no longer present.
 
Isn't there a Ringworld in the OTU canon?

Yes, but it is a dead ringworld, it is a curious artifact and not much else, a lot like the Dyson Sphere that made its appearance in Star Trek: The Next Generation, which served as a giant mouse trap for starships. I wanted a fully functioning ringworld in a universe where it makes sense to have one, enter Alternate Earths, in a normal Alternate Earths campaign you are limited to alternate earths that are actual planets, something like a ringworld would be impossible to travel to as parachronic conveyors aren't spaceships. Traveller has spaceships so its parachronic technology would be space based and this opens up whole new possibilities. The Imperium's technology is based on found wormholes from the Ancients, so if there is not a wormhole leading there, they can't go there. Each wormhole is unstable and only allows passage when incorporated as part of a modified jump drive, for an instant the jump bubble inflates the wormhole so a starship can enter, this is the wormhole drive.

The cost of a wormhole drive is similar to a jump drive, it requires jump furl and passage through it takes a week, that week inside the wormhole is time that is only experienced by the crew and passengers of the starship, as their local arrow of time has been turned sideways.

At the present time, the imperium only has one wormhole for each universe it can explore, so for the time being only one starship can visit a parallel universe at a time. It could be a large starship, it would require a more powerful wormhole drive, but only one starship at a time can use a given wormhole, so the Imperium can only send one starship at a time to investigate the ringworld, if it wants to send another starship then the first one it sent has to return and its wormhole transferred to a new starship. Fortunately wormholes are very elastic, it simply requires more power to stretch one around a larger starship. As the research base on Luna has limited funding, it can only at this time afford a fleet of starships of 800 displacement tons or less, most of this research is unknown to the public, the Imperium is afraid that this technology could be weaponized, so they keep it secret and low profile so the enemies of the Imperium don't get wind of it, one of their starships has already been stolen by a Solomani Agent, this was 25 years ago, and he has never been heard from again. Some starships just never return from their missions and no one ever learns what happened to them, that is a risk every crewman takes when exploring a parallel universe, the only way to and from that universe is by that one starship, if it gets destroyed, the wormhole and that universe is lost. The Imperium is aware of two other societies that can travel to parallel universes, Homeline and Centrum, their technology doesn't suffer from those limitation. The relations between homeline and the imperium are cordial, but Homeline doesn't trust the Third Imperium because its an empire, and thus doesn't want to give it its parachronic technology because the Imperium might use it to conquer Homeline's Earth.
 
I just had an interesting thought. What if 10% of the Ringworld's atmosphere was helium-3? With walls 1,000 miles high to hold in atmosphere, more importantly the tops of those walls under 1g just as the ringworld floor, that ought to be able to hold onto the helium-3, and if not, just make the rimwalls taller until it does. If the walls were 10,000 miles high, that ought to be enough and would hardly affect the mass budget for the ringworld, and you would need a Jupiter's mass anyway.

You could breath in and out an atmosphere that was 10% helium-3 without even knowing it, but fusion reactors can run on it. Atmosphere processors can separate it out by cooling the atmosphere in the intake so that carbon-dioxide freezes to dry ice, and nitrogen and oxygen liquefied and collects in a tank until you have only the helium-3 left, which you can feed into the fusion reactor and power the process of liquidating the atmosphere to gain more helium-3. All that liquid air might come in handy too, but if not you can just vent it back into the atmosphere.
 
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