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Bluecloak
2008-03-07, 08:09 AM
Right then folks, I am making a fantasy setting using a map of the Earth in the distant future - specifically, this one: http://www.scotese.com/future2.htm

Now, it would be neat if the players eventually realise that the world is in fact Earth in the distant future (...enter Charlton Heston: "God damn you! God damn you all to hell!"...). But the problem is of course, what human artifacts or traces of civilisation could possibly remain after such a long time? I remember reading in "The Science of Discworld" that if humanity was wiped out today, the only things left of us after one million years would be some satellites and some debris on the moon. That didn't sound too fun, but I was wondering if any of you more knowledgeable world-builders think that it would really be that bad? I am not asking for sunken cities, abandoned missile silos with fully functional nukes or even the Statue of Liberty - it is supposed to be a fantasy setting, after all - but would there really be nothing made, caused or otherwise influenced by humanity that would make it through 250 million years? Any mysterious, unidentifiable artifacts, indestructible plastics, anything at all?

Thankful for any answers on the matter:smallsmile:

Tempest Fennac
2008-03-07, 08:15 AM
Someone on BurnHollywoodBurn's Scariest Theory Ever thread mentioned that they read somewhere that after just 20,000 New York City would be replaced by thick forest to the point where you wouldn't be able to tell that a city was there, so the chances of there bing anything after 250,000,000 years is rather implausible. I'll try to find the thread for you in a minute.

EDIT: Here's the thread: http://www.giantitp.com/forums/showthread.php?t=71960 . I think the relevant bit is on page 3 near the bottom (the whole thread could be of interest to you for your campaign, though).

Theodoxus
2008-03-07, 08:21 AM
On a slightly off-topic highjack - is it just me, or does Pangea Ultima look suspiciously like Faerun? Move and stretch antartica/australia into the southern reaches... and it's pretty freaking close.

Probably just a coincidence though.

kamikasei
2008-03-07, 08:26 AM
If humanity were wiped out today we wouldn't leave behind much of anything long-lasting besides nuclear waste, non-biodegradable plastics, and some things like cut and artificial diamonds. Most of this would probably get buried pretty quickly. Given our propensity for settling along coasts, erosion and changes in sea level would submerge or carry away a lot. Most of our stuff requires constant maintenance; we don't build for periods longer than decades for the most part. Very little of the material we use is not vulnerable to the elements.

If the campaign is just "Earth 250 million years from now" then you can have the humanity of the next several centuries or millenia alone leave behind all sorts of stuff. Domed cities capped with spun diamond. Self-repairing machinery and nanotech (probably gone a little nuts as bugs have gone uncorrected for eons). Megastructures on the surface and in orbit, and connecting them (space elevators with active defences, the indestructible shells of crashed habitats, etc.). Scrith. Xeelee construction material. Computer networks consisting of giant bacteria/fungus/nanite hybrids spread through the entire crust so that the entire planet is one or more dormant hive minds. Make the planet cold and dark and explain that it's only still habitable because it was moved much closer to the sun after the rest of the solar system was dismantled and the star turned into a Matrioshka brain.

Remember that 250 million years ago mammals and dinosaurs hadn't yet fully branched off from reptiles. It is a very very long time. Artifacts that would stick around for that long would need to be the sort that could last until the heat death of the universe.

Tempest Fennac
2008-03-07, 08:31 AM
Those are excellent points, kamikasei. It remindfs me of a TV series I saw a few years back which was about how scientists imagined creatures would evolve if humans left the planet for some reason. I think they said there's a chance that squids would evolve into landbased creatures before possibly developing technology. I'm sorry that I can't remember what it was called (it was a really good series). If anyone does know what it's called, please could you mention it (you may find it useful, Blue Cloak).

Funkyodor
2008-03-07, 08:32 AM
What kind of traces are you talking about? Like obvious traces like the destroied statue of liberty in Planet of the Apes, or If you dug up a 5x5x5 mile cube of the planet and sifted through it?

Either go big or go small. Big is usually obvious like the statue thing, but small, like a neat muddy little do-dad in the stream someone finds. Some concave glass looking thing that really screws your vision up if you look through it. Wait, that's a lens from someones glasses! Or some small triangular piece of metal that kinda looks like an V, and chimes when you press it. Draw a Star Trek communicator upside down and see how long it takes them to figure it out. Heh, a perfectly preserved Twinkie would be funny, but not realistic. But then I don't think any of the previous items are.

Tyger
2008-03-07, 08:32 AM
Well, 250 million years ago is roughly the late Permian early Triassic period, one of the most major die offs of all life (upwards of 95%) and lead to the rise of th dinosaurs... and we have fossil evidence of that period, and earlier. So is not unreasonable to assume that you would have a fossil record. The difference of course is that the average person is so very unlikely to a) find a 250 million year old fossil and if they do b) recoginize it for what it is.

That is a huge timespan... life on earth went from the trilobites and beetles, to modern civilization in that time span. It would be very unlikely that anything that did survive that long would be even recognizable to the new inheritors of the earth (who would not likely be "humans" as we know them). Of course, when you throw magic into the mix, anything is possible. :)

hewhosaysfish
2008-03-07, 08:41 AM
Fossilised footprints (http://www.genesispark.org/genpark/foot/foot.htm) with a Nike Swoosh on the bottom?

But for man made objects, unless it is actually, truly indestructible then I don't see anything surviving that long in a recognisable form without maintenance...

So That leaves us with:
1) Something indestructible. But be careful. Players can get very inventive if you just hand them the proverbial Immovable Object.
2) Something unrecognisable. Kinda defeats the point.
3) Self-replicating nano-bots! Who needs maintenance? Also provides numerous plot hooks, like "What have these things been doing for the few aeons?" Genetically engineered lifeforms would also reproduce without mankind but would be harder to spot as being man-made.

Edit: Ninjas! Serves me right for stopping to check my facts...

PollyOliver
2008-03-07, 08:45 AM
I'm not sure exactly what level of technology you're going for--in the lost earth civilization or in the new one--but as the previous poster said, either go big or very small. Huge, sprawling deserted cities with territorial robot caretakers, or just small fragments, maybe at a fossil dig. There was a book I read in middle school about what would happen if either aliens or humans very far in the future (sorry, don't remember which) were to catalog our things the way we catalog the belongings of ancient civilizations, and it was quite amusing.

The toilet was a water basin for washing, while the sink was an altar. The television was also an altar (being placed in most homes in a position of significance, with chairs surrounding it and facing inward) while the remote was a scepter for use in ceremonies involving the TV. There were all sorts of amusing little misinterpretations.

If someone on your world was doing a dig (again, I don't know the level of technology you're working with, but even in the 1600's and earlier there were some limited digs, though they were more about treasure-hunting) and found something, like a fossilized fragment of a Nike footprint (just take a charcoal print of the bottom of your shoe, and tear it so they can't tell it's foot-shaped) or some worthless "fake silver" coins with an ugly bird on them and didn't know what to make of them, they might throw them out, or, if the PCs were friendly, show it to them. Just some thoughts.

Telonius
2008-03-07, 08:50 AM
Twinkies and Spam.

Other than that, the places that would have the best chance of something surviving would be near deserts. Anything coastal will be destroyed by then. From that map, Peru, Tibet, and the US Plains States look like they have a decent chance of something surviving above ground. Not much of a chance, even then. If anything, it will probably be something along the lines of the top of a radio tower, or steel girders from the top of a skyscraper.

Buried in the dirt is another story altogether. Plastic and nonbiodegradable trash might be preserved for that long, though I really don't know for sure. Archaeological digs would be able to unearth something, especially from the massive trash heaps we've left across the world. (If anyone is digging for oil or coal, they might find traces).

EDIT: I think I read that book too. "Motel of the Mysteries," right?

Wolf53226
2008-03-07, 08:51 AM
Well, according to this show which I watched Life After People (http://www.history.com/minisites/life_after_people/) put on by the history channel, things like the Pyramids, the Great Wall of China and Mount Rushmore would be some of the last surviving things, since they are made of stone. All metal objects will have corroded away, same with almost all plastics, paper and just about any other substance. Even at that, those things I listed aren't going to look anywhere near the same, erosion would have made them a shadow of what they once were and might even be unrecognizable. But generally you would be looking for things made of stone and the like that are somewhat protected from erosion in some form, like being land locked and low rainfall, but even then wind is going to erode them, it just takes longer.

kamikasei
2008-03-07, 08:51 AM
3) Self-replicating nano-bots! Who needs maintenance? Also provides numerous plot hooks, like "What have these things been doing for the few aeons?" Genetically engineered lifeforms would also reproduce without mankind but would be harder to spot as being man-made.

Saying nanobots are zero-maintenance is like saying you could leave a piece of software running on an Impossibly Perfect Computer (no hardware failures) for 250 million years and nothing go wrong. They are the sort of thing that could survive for that long but would effectively be a new form of life. And when I say "new form of life" I don't mean "new species", I mean "something other than DNA-based life and about as diverse".

Which is an intriguing possibility. Nanotech distributed throughout and absorbed into the ecosystem, like mitochondria or something similar. Computers and communications similarly distributed and absorbed. It would allow a pretty cool magitech fantasy setting where the tech has moved so far past how we today think of it that you could literally have intelligent locations and supernatural beasts. If you assume the AI is totally alien and uninterested in humanlike motivations it avoids the god problem (think something like the Pattern Jugglers from Alistair Reynolds).

@Bluecloak: how do the players end up in this setting? Are they magically transported there or is it in fact just where they live, a place inhabited by humans? How are there still recognizably human humans on Earth in 250 million years? Are they throwbacks? Transplants? Maybe godlike aliens or posthumans seeded the population back on the planet as an experiment. Maybe a cryogenically-preserved settlement awoke with amnesia and all their data stores broken. The question of what happened in the intervening 250 million years to leave beings that look and think like modern humans around constrains a lot of what might be left behind.

Iku Rex
2008-03-07, 09:06 AM
I haven't read it, but the book The World Without Us (http://www.worldwithoutus.com/toc.html) (wiki (http://en.wikipedia.org/wiki/The_World_Without_Us)) covers questions like this. Apparently even Mount Rushmore will "only" last 7.2 million years (http://www.american-presidents.org/2008/01/will-mount-rushmore-last-forever.html) at best.

Bluecloak
2008-03-07, 09:16 AM
Thank you all for that valuable input :smallsmile: And a special thank to Tempest Fennic for that link, and to Kamikasei for the weird technology suggestions. Yes, it's true I don't actually have to go with the "humanity wiped out today" scenario, but could make us survive a bit longer. Not sure yet...


@Bluecloak: how do the players end up in this setting? Are they magically transported there or is it in fact just where they live, a place inhabited by humans? How are there still recognizably human humans on Earth in 250 million years? Are they throwbacks? Transplants? Maybe godlike aliens or posthumans seeded the population back on the planet as an experiment. Maybe a cryogenically-preserved settlement awoke with amnesia and all their data stores broken. The question of what happened in the intervening 250 million years to leave beings that look and think like modern humans around constrains a lot of what might be left behind.

It's still on the brainstorming phase, but the players are supposed to be born on this world. Like I said, it is supposed to be a traditional fantasy world, just with the "future earth" twist. Exactly how I am going to explain some things, I am still working on, since gods and magic are supposed to exist. Maybe those things existed all the time but we modern people neglected and forgot about them. Or maybe humans somehow evolved to god-like beings that are now being worshipped by the creatures they have made into their (old) image. Or maybe we left in generation ships, got caught in some pseudo-scientific time-twist thingamabob, got back to earth millions of years later (where a lot of entirely new species had evolved) and then lost our memory of our old civilisation.

In short, it doesn't have to be too realistic; after all, the hyborean age as well as Middle-Earth are supposed to be our distant past (and not even all that distant, at that), and the Dungeons & Dragons setting Mystara is set on Earth about 150 million years ago (in fact, doesn't it even say in the old golden Immortal box that the setting is our world millions of years ago?).

Like I said, I understand that there will not be any possibilities of mysterious undersea city ruins or the Statue of Liberty, unless I go with Kamikasei's suggestion with futuristic materials that might survive for that long. I was really just wondering if anything small could survive - anything from nuclear waste to fossilized footprints with the Nike swoosh (that was a good one:smallbiggrin: )

Anyway, thanks for your input so far.

Tempest Fennac
2008-03-07, 09:42 AM
I just remembered the program's name: it was called The Future is Wild: http://en.wikipedia.org/wiki/The_Future_is_Wild . Also, looking at what you think the setting will be, you may find a game called Inherit the Earth to be useful to a small degree: http://en.wikipedia.org/wiki/Inherit_the_Earth .

Zincorium
2008-03-07, 09:59 AM
Yeah, I'm going to side with 250 million years as just being a purely speculative campaign, there's just so very little we can accurately predict, even within the next 40 years, that it's all a nebulous cloud of possibilities.

The nanotech based ecosystem is a really nifty idea, especially if you factor in all the pollution we'll create before we die. Seas choked with algae and overrun with matrix-esque motile robots that survive and replicate by filtering out the heavy metals from the deeper waters and absorbing the dim light from the blackened sky.

AKA_Bait
2008-03-07, 10:18 AM
Exactly how I am going to explain some things, I am still working on, since gods and magic are supposed to exist. Maybe those things existed all the time but we modern people neglected and forgot about them. Or maybe humans somehow evolved to god-like beings that are now being worshipped by the creatures they have made into their (old) image. Or maybe we left in generation ships, got caught in some pseudo-scientific time-twist thingamabob, got back to earth millions of years later (where a lot of entirely new species had evolved) and then lost our memory of our old civilisation.

I relatativley neat soloution for this is to use some of the nano-tech ideas Zincorum mentioned. I know that this has come up in some novels I have read but I'll be damned if I can remember which ones (sorry authors!).

Basically, the idea is this:

Nanotech is magic. A fireball? It's a bunch of nanites that go forth and explode. Dispel Magic? It's an EMP. Raise dead? Nanites go in, fix the damaged parts, and jump start your brain. Mage armor? It's a shell of nanites that deflect incoming objects. None of this needs to be apparent to the players though. If you are still using 3.x for this the vancian notion that spells are actually effected by some sort of semi-sentient creatures that magicians command can be the prevailing logic as to why magic works.

Races are just evoloution/biotech of the past. 250 million years is a long, long time. The human race would have branched off. Think the division in Well's the Time Machiene just spread over all of the humaniod races in D&D. I can easily see some of the divisions. Minotaurs are the distant descendants of people genetically engineered for contact sports etc.

Gods: System designers. Gods are just humans (or other sentient species) that have figured out enough of the programming of the nanites to be able to do things that other races cannot. Getting to godhood is really something more like getting Admin access to the system.

Edit: An additional thought, you can actually use this concept in with your 'big reveal' as well. Some of the 'gods' might be history buffs. Sure, it's not the original Booklyn Bidge, but it looks like it and Robinson God of Social Integration keeps it around as a memento (maybe even as a temple).

Bluecloak
2008-03-07, 10:25 AM
On a slightly off-topic highjack - is it just me, or does Pangea Ultima look suspiciously like Faerun? Move and stretch antartica/australia into the southern reaches... and it's pretty freaking close.

Probably just a coincidence though.

Probably not. Old Mystara was, after all, based on Earth 150 million years ago, something like this: http://www.scotese.com/late1.htm :smallwink:

Edit: Compare with this map of Mystara: http://www.pandius.com/master-outer-world.png

brian c
2008-03-07, 10:29 AM
Well, according to this show which I watched Life After People (http://www.history.com/minisites/life_after_people/) put on by the history channel, things like the Pyramids, the Great Wall of China and Mount Rushmore would be some of the last surviving things, since they are made of stone. All metal objects will have corroded away, same with almost all plastics, paper and just about any other substance. Even at that, those things I listed aren't going to look anywhere near the same, erosion would have made them a shadow of what they once were and might even be unrecognizable. But generally you would be looking for things made of stone and the like that are somewhat protected from erosion in some form, like being land locked and low rainfall, but even then wind is going to erode them, it just takes longer.

But even Mt Rushmore and the Pyramids won't last 250 million years; it would be a miracle for them to be even standing anymore and not completely eroded away, but the faces on Rushmore would be long gone and the Pyramids would be, at best, buried under the Sahara. Hm... finding a series of enormous pyramids under hundreds of feet of sand would be pretty remarkable, but the fact is they wouldn't last that long. 1 million years sure, 10 million might still be okay, but 250 million is a whole different scale.

Citizen Joe
2008-03-07, 11:20 AM
Your continental drift is in the wrong direction. The continents would spread further apart rather than form a super continent. And I don't think they would crash together on the other side either. They are sort of acting like waves on the decay side where they rise up over the subduction plate and then parts just crumble off and re-enter the mantle. That is not to say there won't be any crashing of continents but they just wouldn't go the direction you're positing.

One trick you can to is turn the world off its current axis. Maybe make the 'north pole' in the Saharra and the 'south pole' around Hawaii. One of the theories is that the Hawaiian Island chain is formed by a 'hot spot' under the Crust which forms a volcanic island. The continental plate is moving though, so the crust shifts over the spot forming new islands. If the axis shifted, you would be able to see the visible effects in the form of an island chain leading up to wherever the pole is. This also does weird things as the glaciers melt and reform elsewhere. With the ice missing, the plate would rise, meanwhile the new glacial areas would sink.

Callos_DeTerran
2008-03-07, 11:36 AM
I relatativley neat soloution for this is to use some of the nano-tech ideas Zincorum mentioned. I know that this has come up in some novels I have read but I'll be damned if I can remember which ones (sorry authors!).

Basically, the idea is this:

Nanotech is magic. A fireball? It's a bunch of nanites that go forth and explode. Dispel Magic? It's an EMP. Raise dead? Nanites go in, fix the damaged parts, and jump start your brain. Mage armor? It's a shell of nanites that deflect incoming objects. None of this needs to be apparent to the players though. If you are still using 3.x for this the vancian notion that spells are actually effected by some sort of semi-sentient creatures that magicians command can be the prevailing logic as to why magic works.

Races are just evoloution/biotech of the past. 250 million years is a long, long time. The human race would have branched off. Think the division in Well's the Time Machiene just spread over all of the humaniod races in D&D. I can easily see some of the divisions. Minotaurs are the distant descendants of people genetically engineered for contact sports etc.

Gods: System designers. Gods are just humans (or other sentient species) that have figured out enough of the programming of the nanites to be able to do things that other races cannot. Getting to godhood is really something more like getting Admin access to the system.

Edit: An additional thought, you can actually use this concept in with your 'big reveal' as well. Some of the 'gods' might be history buffs. Sure, it's not the original Booklyn Bidge, but it looks like it and Robinson God of Social Integration keeps it around as a memento (maybe even as a temple).

This nanite-magic idea is made of WIN. Hmm...I wonder perhaps if one could design a PrC that grants further control of the nanites (Essentially Dragon Ascendant for humiods)

Chronos
2008-03-07, 12:30 PM
If humanity were wiped out today we wouldn't leave behind much of anything long-lasting besides nuclear waste, non-biodegradable plastics, and some things like cut and artificial diamonds.I think that for a lot of people, there's only one value for "a long time", and that anything after that just all blurs together. When people say that plastics last a long time, they mean hundreds of years. When they say that nuclear waste lasts a long time, they mean thousands. Diamonds aren't forever; they turn to graphite in a couple million years. 250 million years? All of them are dust, and to dust they have returned.

The OP was correct that the only things which would survive are in space. But this is not a lost cause: Many satellites are visible to the naked eye. Admittedly, these tend to be the low-Earth-orbit ones, which would also be gone by this time, but it wouldn't be too much of a stretch to put some larger or more reflective satellites in higher orbits which would still be visible. Now, whether you'd be able to clue your players in enough to recognize them would depend strongly on your players' backgrounds (in particular, on whether any of them are amateur astronomers).

Of course, there's a simpler solution, too... There's no reason that it has to be 250 million years later, is there? There is some point at which traces of our civilization will be almost, but not completely, wiped out. Whatever that time is, just set your adventure then. If you're worried that there won't be enough continental drift by then, leaving the map still recognizable, you can still raise or lower the ocean levels, orient the maps with (what we call) South on the top, and then maybe use the magnetic poles (which could have wandered a random amount in a random direction) instead of the geographic poles for orienting the map.

Zincorium
2008-03-07, 12:46 PM
In regards to the 'nanite magic':

The MMO Anarchy Online does it that way. What's essentially going on there is that there's a utility fog of nanites left over from terraforming the planet (on earth a better explanation is the cleanup of pollution or radioactive fallout) and people who have the right cyberware and software can control them to produce certain effects.

Since the nanites are everywhere, invisible, and can only be accessed through wireless communications, anything done with them would definitely look like magic to anyone watching. Objects moving at a distance, people disintegrating or getting healed, buildings appearing out of the ground... the possibilities are varied.

Two good limitations for this are:

1. The utility fog has corrupted, useless programming in most places. It's memory has to be flashed and replaced with a valid program. Until this is done, the utility fog may either hang in the air, in stasis, or may be actively hostile. Regions where gravity is counteracted, people age rapidly, or just plain disappear are all possible, and these would be tougher to reprogram as they already have a set in operation.

2. The utility fog is limited in it's power source, either storing energy from the sun or relying on special batteries carried by the user. It effectively changes the recharging of powers from per-encounter to per-area and per-day, but with emergency reservoirs to recharge a particular patch.

Jothki
2008-03-07, 01:27 PM
If you want a bigger twist, you could have it so that biological life has long since been extinct, and all living things are actually nanotechnology that has been commanded to assume the shape of the creatures that once inhabited the planet by one or more ancient supercomputers that managed to survive whatever catastrophe wiped out humanity, and have since then been reshaping the planet according to their whims.

Titanium Dragon
2008-03-07, 01:28 PM
Your continental drift is in the wrong direction. The continents would spread further apart rather than form a super continent. And I don't think they would crash together on the other side either. They are sort of acting like waves on the decay side where they rise up over the subduction plate and then parts just crumble off and re-enter the mantle. That is not to say there won't be any crashing of continents but they just wouldn't go the direction you're positing.

You're actually wrong; there's a reason it will look that way. The continents don't move the directions you're moving, and remember that they won't always move the same direction.


I think that for a lot of people, there's only one value for "a long time", and that anything after that just all blurs together. When people say that plastics last a long time, they mean hundreds of years. When they say that nuclear waste lasts a long time, they mean thousands. Diamonds aren't forever; they turn to graphite in a couple million years. 250 million years? All of them are dust, and to dust they have returned.

No, actually; they really do mean millions of years for plastics. Plastics aren't eaten by anything, nor is styrofoam; they'll last pretty much indefinitely short of something evolving which can eat them (the likelihood of which varies; some synthetic materials already have bacteria which have evolved to eat them, and we may actually engineer plastic-eating bacteria).

Another thing that could last a very, very long time is anything made out of titanium; it doesn't really corrode. Possibly bits of fuselage would survive that long.


The OP was correct that the only things which would survive are in space. But this is not a lost cause: Many satellites are visible to the naked eye. Admittedly, these tend to be the low-Earth-orbit ones, which would also be gone by this time, but it wouldn't be too much of a stretch to put some larger or more reflective satellites in higher orbits which would still be visible. Now, whether you'd be able to clue your players in enough to recognize them would depend strongly on your players' backgrounds (in particular, on whether any of them are amateur astronomers).

Actually, this is wrong too; satellites in orbit would crash or fly off, their orbits are not stable indefinitely.

As for structures making it - ironically, stuff like the Pyramids is pretty much the only purely man-made stuff which would probably survive; all the rest would likely be for naught, though again, if someone built something out of something like titanium, it could very well last a very long time.

Honestly, I think you should just ignore plausibility though and just go with whatever. Assuming there is sentient life around, a lot of our structures could last a very long time indeed with the proper upkeep; maybe all that is left of a lot of them are ruins, but people try to keep them up as best they can for religious reasons or whatever. You could make a holy pilgrimage site out of, say, a football stadium or skyscraper, and you could just claim that is how the stuff has survived so long - people have kept maintaining and repairing it as best they know.

Heck, you could even have "cargo cult" style religions where fascimiles (preferably nearly unrecognizable ones) of our modern technology is around by people who try to replicate the form, having long since forgotten its function. Great stone pillars of varied sizes and shapes may represent the skyline of a city, for instance.

Mark Hall
2008-03-07, 02:04 PM
Saying nanobots are zero-maintenance is like saying you could leave a piece of software running on an Impossibly Perfect Computer (no hardware failures) for 250 million years and nothing go wrong. They are the sort of thing that could survive for that long but would effectively be a new form of life. And when I say "new form of life" I don't mean "new species", I mean "something other than DNA-based life and about as diverse".

Poul Anderson wrote a short story about this, actually. It's called "Epilogue", and involves some humans visiting Earth about 3 billion years in the future, after a nuclear war killed most of the planet. Most of the life was evolved from automated resource-extraction barges.

Citizen Joe
2008-03-07, 02:10 PM
Actually, in 250 million years I suspect civilizations would have risen to power and destroyed themselves at least 250 times. How long would it take for the radioactivity to reduce to the point that we could survive in the dead regions? During those dead times, humankind would be basically Stone Age savages. Once they could start populating the nuked areas, technology would advance again for about 10 thousand years and then Humanity destroys itself again. Repeat this cycle to see how many 'super generations' humanity has gone through.

Talya
2008-03-07, 02:20 PM
If humanity still exists in even 1 million years, we'll no longer be recognizable as what we are today, from cultural, technological and possibly even biological standpoints. We're also unlikely to still be on earth. If we survived that long, it's because we figured out how to get off this rock and out to the stars.

"And I was wondering if they will remember us hundred years from now, or a thousand. Then I figured: probably not."
"But it doesn't matter. We did what we did because it was right, not to be remembered. History will attend to itself, it always does."


This is how the world ends, swallowed in fire, but not in darkness. You will live on. The voice of all our ancestors, the voice of our fathers and our mothers to the last generation. We created the world we think you would've wished for us. And now we leave the cradle for the last time.

Mark Hall
2008-03-07, 02:21 PM
Actually, in 250 million years I suspect civilizations would have risen to power and destroyed themselves at least 250 times. How long would it take for the radioactivity to reduce to the point that we could survive in the dead regions? During those dead times, humankind would be basically Stone Age savages. Once they could start populating the nuked areas, technology would advance again for about 10 thousand years and then Humanity destroys itself again. Repeat this cycle to see how many 'super generations' humanity has gone through.

In 250 million years, I hope we've left this planet as our sole place of residence.

Iku Rex
2008-03-07, 02:26 PM
No, actually; they really do mean millions of years for plastics. Plastics aren't eaten by anything, nor is styrofoam; they'll last pretty much indefinitely short of something evolving which can eat them (the likelihood of which varies; some synthetic materials already have bacteria which have evolved to eat them, and we may actually engineer plastic-eating bacteria).Who are "they"?

The book I mentioned above has a chapter (http://www.worldwithoutus.com/excerpt.html) on plastics, and "thousands of years" seems to be the worst-case estimate. Maybe hundreds of thousands of years at the bottom of the ocean. And keep in mind that they're talking about microscopic particles.

Talya
2008-03-07, 02:26 PM
In 250 million years, I hope we've left this planet as our sole place of residence.

My ninja skills are superior, because I'm really a pirate.

Tempest Fennac
2008-03-07, 02:31 PM
If you've never heard of it, Galapagos sounds like a really interesting novel regarding this topic: http://en.wikipedia.org/wiki/Gal%C3%A1pagos_%28novel%29 (I don't know whether that would be helpful regarding creating a new race for your world).

kamikasei
2008-03-07, 03:07 PM
Who are "they"?

"They" appears, tracing the quote chain, to have been me. And I should clarify that I was just listing off the top of my head the longest-lasting artifacts I could think of. I had no particular expectation that any of them would actually last 250 million years (except for the diamond - I did not know that about the graphite, interesting).

So, we can expect that none of what we have today at all will survive that long.

@Jothki: that is a very cool idea.

@Mark & Talya: seconded, or thirded, or whatever. There are few things more depressing in futurology than the assumption that hey, Earth, it's where all the cool kids hang out now and forever and, pfft, Type N>2 civilizations, totally passe. Also, people will always look and act like people and not like posthumans or AIs or consensual hive minds or... bah!

Chronos
2008-03-07, 03:20 PM
No, actually; they really do mean millions of years for plastics. Plastics aren't eaten by anything, nor is styrofoam; they'll last pretty much indefinitely short of something evolving which can eat them (the likelihood of which varies; some synthetic materials already have bacteria which have evolved to eat them, and we may actually engineer plastic-eating bacteria).Getting eaten isn't the only way for things to decay. Plastics start breaking down in a matter of decades just from exposure to sunlight. And the things that sunlight turns plastic into can be metabolized by bacteria.


Actually, this is wrong too; satellites in orbit would crash or fly off, their orbits are not stable indefinitely.Only the ones in low orbits. For the rest, what would cause them to fly off? You'd need to add significant amounts of energy to the system for that to happen, and that energy would have to come from somewhere.

Wolf53226
2008-03-07, 03:36 PM
But even Mt Rushmore and the Pyramids won't last 250 million years; it would be a miracle for them to be even standing anymore and not completely eroded away, but the faces on Rushmore would be long gone and the Pyramids would be, at best, buried under the Sahara. Hm... finding a series of enormous pyramids under hundreds of feet of sand would be pretty remarkable, but the fact is they wouldn't last that long. 1 million years sure, 10 million might still be okay, but 250 million is a whole different scale.

Sorry, having reread my post I realize I could have left that impression, what I meant was that those would be the last remaining signs of our civilization, not that they would last 250 million years, but that they would last the longest of everything ever built. I don't know what an exact time frame would be for these things to deteriorate but yes, by the time 250 million years came around, if no one was protecting these landmarks, even they would have disappeared.

I was hoping that the 250 million years was more of a "in a very distant future" not an exact length of time, in which case you could have those landmarks.

The ending thought of that show I linked to was basically that it was ironic that despite all our technology and advances, the only last remnants of us would be things carved into and out of stone.

Telonius
2008-03-07, 03:39 PM
Getting eaten isn't the only way for things to decay. Plastics start breaking down in a matter of decades just from exposure to sunlight. And the things that sunlight turns plastic into can be metabolized by bacteria.

Only the ones in low orbits. For the rest, what would cause them to fly off? You'd need to add significant amounts of energy to the system for that to happen, and that energy would have to come from somewhere.

Hmm, there's an idea. A collision with some space debris sends one satellite crashing to earth. What's left is twisted wreckage, and an empty coke bottle that was accidentally left in the inner workings.

Emperor Tippy
2008-03-07, 04:02 PM
No trace of humanity would be left on earth.

Now in space is a potentially different story.

If humanity created an automated space infrastructure (theoretically possible) that repaired and replaced its self then said space infrastructure could still be around.

SyrkthTheGreedy
2008-03-07, 04:09 PM
Myself, I have questions that need to be defined by the OP since multiple factors have to do with any given outcome.
How did humanity disappear?

If the answer involves war, conventional or nuclear at least, then there really would be little left. Of course, the implication of the OP is that humanity wiped itself out completely, which makes biological warfare more likely.
Everything left intact but no populace.

This opens up interesting alternative events to what develops after humanity's fall. Many species could take over after humans wipe themselves out, my bet would be for the insects to rise up (being short of lifespan and more adaptable because of the ability to become immune to various things in a short number of generations). Given the 250 million years, it's certainly plausible.

Perhaps the virus resulted in accelerated evolution or de-evolution in humanity? Take a page from Jules Verne (The Time Machine) or Anne McCaffrey (Dragon Riders of Pern) or Piers Anthony (Battle Circle). Humans evolve into upper and lower types or sections of the earth are completely inhospitable to life other than X until the PCs find it is no longer so.
All these bar natural events like comet strikes, electromagnetic surges, natural plagues etc etc.

Another question would be when does humanity get wiped out. Because honestly, if the extinction is complete around our current time period there really is nothing left after 250 million years. Erosion from wind, water, sun (barring rolar radiation bursts) etc would degrade every human structure.
However, if humanity is left alone for a thousand years or so, human technology could possibly be able to leave simple and identifiable objects behind, though this may depart too much from your concept of having the PCs recognize Earth for what it is.

My final question kind of hinges on the responses to the above but I'll ask it anyways. Are the PCs survivors, aliens or colonists? As an example, Battlestar Galactica does a very good job of making a convincing universe that has forgotten the origins of humanity except in "legend" alone. History and myth bear this "amnesia of origins" out in the tales we can sift through from various mythologies (Classical, Norse, African, Sumerian, Polynesian etc etc) and these histories only cover thousands of years! Imagaine the potential of millions of years of lore: erased, retold, rewritten and reinvented. After all, earth is but one hunk of rock in the vast cosmos.

Essentially, with such a vast span of time, you've written a blank cheque for yourself on story.

Edit: As an aside, I note that you said it was a fantasy setting. Does that include magic (arcane or clerical). Since this opens up a bunch of doors that again, writes you a blank cheque for possibilities (exiled gods, original humans who mastered the arcane arts, blah blah blah).

Baxbart
2008-03-07, 04:20 PM
If humanity still exists in even 1 million years, we'll no longer be recognizable as what we are today, from cultural, technological and possibly even biological standpoints. We're also unlikely to still be on earth. If we survived that long, it's because we figured out how to get off this rock and out to the stars.

"And I was wondering if they will remember us hundred years from now, or a thousand. Then I figured: probably not."
"But it doesn't matter. We did what we did because it was right, not to be remembered. History will attend to itself, it always does."


This is how the world ends, swallowed in fire, but not in darkness. You will live on. The voice of all our ancestors, the voice of our fathers and our mothers to the last generation. We created the world we think you would've wished for us. And now we leave the cradle for the last time.

Thats going to bug the living hell out of me... where's that from? I know it, but I can't place it.

endoperez
2008-03-07, 04:26 PM
Working from the nanite idea:


Thousands of years into the future, the Earth (and other planets which might or might not have been terraformed) is an effectively lifeless rock and humanity is doomed to die. Technology has evolved to the level of magic, but due to lack of faster-than-light space travel humans are entombed in their own, dying system. There is still hope, however! Nanites can survive for millions and years and start the process of first cleaning the world, then generating a new athmosphere, absorbing hydrogen and oxygen and making oceans, killing off any newly developing life if any appears, etc etc. The process would take about 230 million years.

Because genetic material would only surive for 500 years or so, the machines would take genes from the gene bank, grow full specimens and extract new gene material. Various corruptions and errors in handling of this material would cause the creation of humanoid races and various hybrid creatures, such as manticores, unicorns, pegasi, gryphons etc. Plants would be released first, after about 200 million years; once plants could survive and athmosphere was about right, various animals would be released. The sentient races would be released about 230 million years after the process started. Force-fields meant to protect the artifacts of the lost civilizations were meant to cease to exist few million years after that, after some kind of civilization would have been created. Most of them failed too early, and only few chosen marks are intact. ANYTHING you choose could have stayed, in some form, as long as someone deemed it important enough to immortalize.

Automated space-stations that extract metal hubris of various satellites and wrecked space-craft and send it back to Earth, because all the metal easily available was mined and sent to space. The initial sendings were huge and are buried deep underground, but as more and more of the metal was collected the last sendings were pretty small, comparable to meteorites. The various procedures used to merge the scraps of different metal would create alloys of special properties (adamantium or whatever), and these would still occassionally be sent down to Earth. Dwarves would have stories of entire mountains shaped like malformed metal cubes, etc. In effect, parts of the world are clearly created and designed.

Some nanites would have been programmed to actively create replicas of old monuments or something that would help the new sentient life to develop faster, e.g. a "magic force" that creates "an endless supply of tiles, free for anyone to take", that is actually trying to build pyramids, the great wall or something. Various representations of myths or symbols would sometimes appear from thin air, quickly decay (corruptions, bugs) and then disappear. Both holograms and actual buildings would work. This allows for various myths based on real-world buildings, events and such, as well as providing actual "visions" which the holy men receive. Holy men would, of course, in some way resemble the ancient humans enough that the corrupted nanites recognize someone who might understand their message.

Parts of the world would have been nano-terraformed into perfect farming area, but due to bugs these fields would be carved and kept to the mountainside, several meters under the water near a coast, or something similar. Mages could discern that some kind of spirits try to farm the lands promised to them in ancient past, and a major quest would be based around either getting the nanofarm to change into somewhere suitable, or making the area it tries to farm fertile (dam the ocean!). This could be used to provide any continuous effect you might want to include.


In short: the machines did it.

Solo
2008-03-07, 04:29 PM
Actually, this is wrong too; satellites in orbit would crash or fly off, their orbits are not stable indefinitely.

You ever see that bright round thing in the sky commonly referred to as the moon?

Citizen Joe
2008-03-07, 04:29 PM
That's a Babylon 5 reference

Citizen Joe
2008-03-07, 04:30 PM
You ever see that bright round thing in the sky commonly referred to as the moon?


L point satellites would remain stable (barring meteor collision).

Kami2awa
2008-03-07, 04:32 PM
Right then folks, I am making a fantasy setting using a map of the Earth in the distant future - specifically, this one: http://www.scotese.com/future2.htm

Now, it would be neat if the players eventually realise that the world is in fact Earth in the distant future (...enter Charlton Heston: "God damn you! God damn you all to hell!"...). But the problem is of course, what human artifacts or traces of civilisation could possibly remain after such a long time? I remember reading in "The Science of Discworld" that if humanity was wiped out today, the only things left of us after one million years would be some satellites and some debris on the moon. That didn't sound too fun, but I was wondering if any of you more knowledgeable world-builders think that it would really be that bad? I am not asking for sunken cities, abandoned missile silos with fully functional nukes or even the Statue of Liberty - it is supposed to be a fantasy setting, after all - but would there really be nothing made, caused or otherwise influenced by humanity that would make it through 250 million years? Any mysterious, unidentifiable artifacts, indestructible plastics, anything at all?

Thankful for any answers on the matter:smallsmile:

Not much would last that long. 250 million years is long enough for a mountain to rise and erode to dust. Even artefacts left on the moon or in space would eventually be eroded away by micrometeorites. It's possible you would find:

- Some longer lived radioactive waste.
- Artificial diamonds (maybe with symbols and writing on them from the manufacturer for intelligent species to wonder about).
- Substances in the earth that couldn't occur naturally.
- Fossil artefacts. A plastic bottle could probably create a fossil; the plastic would have long disintegrated.

Of course, if mankind advanced enough to create new organisms or build a Dyson Sphere, a lot more traces would survive.

Human Paragon 3
2008-03-07, 04:39 PM
But that was before the Great Circuiting!

...

And that is where babies come from. For robots.

/How long ago was that?
//Thousands of years ago!

kamikasei
2008-03-07, 04:40 PM
You ever see that bright round thing in the sky commonly referred to as the moon?

What makes you assume the moon's orbit is stable indefinitely?

Bodies in complex orbital systems will eventually either collide or be ejected. See here (http://en.wikipedia.org/wiki/Heat_death#Planets_fall_or_are_flung_from_orbits:_ 1015_years) (looking for a better, nearer-term reference).

Emperor Tippy
2008-03-07, 04:42 PM
Humanity will never build a dyson sphere unless we get out of our solar system. There isn't enough mass in the solar system to make a dyson sphere (a ring world would take all mass not currently inside the sun to construct).

---------
To the OP: The first question you need to answer is when humanity gets wrecked. Today? A hundred years? A thousand years? A million?
Next is how much warning humanity had.

Nuclear Winter is a good idea. It can be suitably quick while still dealing with most of humanity.

kamikasei
2008-03-07, 04:52 PM
Humanity will never build a dyson sphere unless we get out of our solar system. There isn't enough mass in the solar system to make a dyson sphere (a ring world would take all mass not currently inside the sun to construct).

Dyson Spheres or Ringworlds of the human-habitable-interior sort are far too inefficient. You want a Dyson Swarm (http://en.wikipedia.org/wiki/Dyson_Sphere#Dyson_swarm) for power capture or a Matrioshka brain (http://en.wikipedia.org/wiki/Matrioshka_brain) for habitation (though not by meatbags). If you really want pathetic fleshlings to have a place, build Orbitals (http://en.wikipedia.org/wiki/Orbital_%28The_Culture%29). Better redundancy that way (and more variety possible, too).

Solo
2008-03-07, 05:01 PM
What makes you assume the moon's orbit is stable indefinitely?

The moon is receding at a rate of 4 cm per year. Not indefinitely stable, but it will be there for a looooooong time.

As an aside, by the time the moon gets far enough away from the Earth to escape, the sun will have probably gone into a supernova and wiped out all life on earth or something so it will cease to matter.

kamikasei
2008-03-07, 05:06 PM
The moon is receding at a rate of 4 cm per year. Not indefinately stable, but it will be there for a looooooong time.

By the time the moon gets far enough away from the Earth to escape, the sun will have probably gone into a supernova and wiped out all life on earth or something.

Yeah. A long time. Not indefinitely. We're talking about geological timescales here, shading into cosmological.

We're also talking about large numbers of small satellites and all the n-body problem problems that brings with it, so the Moon is a poor example.

Solo
2008-03-07, 05:14 PM
As far as "satellites leaving a trace after 250 million years", however, I believe the moon suffices as an example?

Talya
2008-03-07, 05:18 PM
Thats going to bug the living hell out of me... where's that from? I know it, but I can't place it.

Deconstruction of Falling Stars, Babylon 5.

kamikasei
2008-03-07, 05:21 PM
As far as "satellites leaving a trace after 250 million years", however, I believe the moon suffices as an example?

If it's got a big "hey guys, this used to be Earth!" sign on it, sure.

The fact that a fantasy setting has a single moon that looks the wrong size and would presumably be mentioned only in passing is not exactly a glaring hint to the players.

Actual artificial satellites that would serve as evidence of past human civilization certainly would not be likely to still orbit (unless specifically set up to do so, if that's even feasible).

Solo
2008-03-07, 05:25 PM
If it's got a big "hey guys, this used to be Earth!" sign on it, sure.


You mean like a Chinese moon base?

Chronos
2008-03-07, 05:30 PM
We're also talking about large numbers of small satellites and all the n-body problem problems that brings with it, so the Moon is a poor example.Except that that depends on the number of satellites up there, and the volume of space they occupy. Orbits high enough to not decay from atmospheric friction are sparse to begin with, and whenever you do chance to eject something, or crash one into Earth, they'll get even sparser. The last few left would be of comparable stability to the Moon.

kamikasei
2008-03-07, 05:38 PM
You mean like a Chinese moon base?

Yes, a moon base still extant after 250 million years, visible with the naked eye from Earth (or, I suppose, known to the characters via investigations of astronomers who may or may not exist), which is somehow identifiable as having been built by humans from Earth, would be a dead giveaway.

But don't you think that's wandering rather far afield from "would our satellites in orbit be evidence"? If you want to argue that the players could be tipped off by something about the moon, just do so. Orbits decay or evaporate. Artificial satellites launched to serve some purpose for the people below (as opposed to being there just to be there, for as long as possible, for whatever reason) will crash or escape over millions of years. The Moon is irrelevant to that point.

ShadowSiege
2008-03-07, 05:49 PM
I'm with most everyone else on this. There'd be no trace of humanity left on Earth. 250 million years is too long of a time scale. Bronze statues would be the largest artifacts of humanity, surviving at least 10 million years, but another order of magnitude may be too much for them.

Kudos to Talya for the B5 reference.

Talya
2008-03-07, 05:56 PM
Kudos to Talya for the B5 reference.

I can't come to a website where the owner calls himself the "Giant in the Playground" without getting B5 stuff in my head.

Bierhoff
2008-03-07, 06:17 PM
Here's another idea of a place one might be able to find traces of humanity, in rock.
No, not fossilized, although I'm sure there'll be some of those kicking around.
What I'm thinking of is places like Pompeii, Herculaneum, or Akrotiri. These cities were buried within solid chunks of rock. In all likelihood Pompeii will have more rock covering them again in the future (Akrotiri may well blown up it the volcano it's on erupts again). So long as no one digs a city like that up it'll be protected from the elements for along time. Granted erosion may expose some of the city, but... maybe not. I wouldn't be surprised if Herculaneum would out last the Great Wall if people hadn't already dug into it. Furthermore, encased in rock lots of objects could service for very long time. I think ceramics in particular would last.
Now, on top of erosion the biggest threat to volcanically preserved structures would be plate tectonics. Since most volcanoes are near fault lines the pressures on the stone the city is in and by extension the city itself may cause distortion and metamorphosis over the time scale in question. These process also may produce vertical movement.
For instance, say Vesuvius blows again and buries Naples and humanity dies out soon afterwards, so the city is never dug out by people. Natural processes will cover the rock Naples is in with soil. Some of this soil may erode, as may some of the rock and the buildings they contain. Another eruption may cover the city with another layer of volcanic rock. In time, the movement of Africa past Europe may force Italy up, out of the receding Mediterranean, such that Naples is now is now inside a mountain in a range similar to the Alps. The forces pushing the city up may not be even, causing the buildings to twist. But the movement is so slow that many of the materials in the city don't snap, they just bend. Some materials may erode, their chemicals reacting with the rock around them to produce new compounds, creating a fossilized city in the process. The pressures may cause other materials to change. Limestones transforming into marble for instance. In time some of the city may become exposed. "People" wandering in the mountain range which once was Italy may find strange shaped rocks or wonder at the bizarre patterns in the cliff face, the cutaway of an apartment building. Some may tell stories of the ghosts who haunt those rocky slopes. Eventually their paleontologists may realize that there once were many eras to the earth which predate them and they may even figure out that the strange rocks in the mountains, which once were Italy, are left overs from that by gone age. And they'll wonder what strange, brutish creatures made such nests for themselves.

edit:
Talya: so true. B5 rocks

CthulhuM
2008-03-07, 06:58 PM
You might want to take a look at Ilium (http://en.wikipedia.org/wiki/Ilium_%28novel%29)and its sequel, for ideas on what aspects of the wierd future to include. Those books are set on a much shorter timescale than you're talking about (something like 10,000 years in the future), but they have some interesting ideas - transhumans pretending to be gods and "normal" humans wandering around with little or no understanding of the technology around them and the nanotech they make use of.

The series also does a good job of littering the world with odd and inexplicable remnants of past high-tech civilizations - dense rings of orbiting satellites visible from the ground, a network of teleportation devices connecting the strung-out remnants of humanity, a mile-wide pit that apparently leads down to the outer mantle in the middle of what used to be Paris and an air-filled trench crossing through the northern Atlantic being just a few examples.

Talya
2008-03-07, 07:26 PM
Over the next 5 billion years, Sol will burn steadily hotter, until it reaches the end of its main sequence and becomes a red giant.

Long before that time is up...long before even the 250 million year time frame you are discussing, earth will have grown far too hot to sustain life as we know it. I forget how long now, but I seem to remember it being on the scale of a hundred million years or so.

Humans have only been around for a million years or so, so it's rather stretching our luck to suggest we'll still be around by that time anyway. Of course, we can't find much for artifacts of civilization more than 3 thousand years old or so, with a few very rare items dating back 6-10 thousand years. You think we ever built any notable civilizations in the 990,000 years prior to that we existed? I imagine we did. Good luck ever learning about them, though.

Bierhoff
2008-03-07, 08:17 PM
However, you also have to bear in mind that they figure close to half of all humans who have ever lived are currently alive, so we are currently making a much greater impact than we ever have before... by a long shot. Also there weren't many civilizations leaving things around to find more than 3,000 years ago and we've got a fare bit of stuff from the once that were back at least 5,000. Although that's rather that's rather inconsequential compared to the time frame of the initial post. All things considered though, I think we have surprisingly good knowledge about early life on earth.

Now, if you want to play around with strange things that'll happen to the earth in the future, the rotation of the planet is slowing down so that eventually there will be one face that is constantly facing the sun and one out to space. It'll sorta be like how there only one side of the moon ever faces Earth. granted we're only losing 2.2 seconds off the day every 100,000 years. But you know a world with a day side and a night side could make for interesting adventuring. All habitation would have to be some where in the dusk zone between the two.

Solo
2008-03-07, 08:21 PM
Over the next 5 billion years, Sol will burn steadily hotter, until it reaches the end of its main sequence and becomes a red giant.

Long before that time is up...long before even the 250 million year time frame you are discussing, earth will have grown far too hot to sustain life as we know it. I forget how long now, but I seem to remember it being on the scale of a hundred million years or so.

Humans have only been around for a million years or so, so it's rather stretching our luck to suggest we'll still be around by that time anyway. Of course, we can't find much for artifacts of civilization more than 3 thousand years old or so, with a few very rare items dating back 6-10 thousand years. You think we ever built any notable civilizations in the 990,000 years prior to that we existed? I imagine we did. Good luck ever learning about them, though.

Ice core samples indicate that we are the only civilization so far to make extensive use of fossil fuels.

If you're suggesting that there were advanced civilizations before us, how do you suppose they made it without using fossil fuels for energy?

Talya
2008-03-07, 09:09 PM
Ice core samples indicate that we are the only civilization so far to make extensive use of fossil fuels.

If you're suggesting that there were advanced civilizations before us, how do you suppose they made it without using fossil fuels for energy?

Oh, not as advanced. But remember, the pyramids of egypt and mt. rushmore and similar stone monuments will be around long after all other traces of our existence fade...i'm sure similar things have been made by other ancient civilizations before recorded history.

Lupy
2008-03-07, 09:10 PM
:smallamused: Wow, no one has mentioned this yet. I believe we all agree that 250 million is too far to be realistic. Go read Shannara. There are a handful of ruined things (titanium girders in a handful of skyscrapers, plexiglass, concrete cities that have petrified)... And a mad computer with all of our current knowledge built to protect humanity, but not realising that the current civilization is humanity, and so attacking them with it's robos... Antrax anyone? A few books copied generation after genartion by the very old that contain knowlidge (maybe the Bible, the Quaran, the Torah, the Lord of the Rings, a few Reference books, D&D 7th edition...) world altering stuff no one wants to forget. And legends that one day God will free them from the Metal-ones...

Neutrino
2008-03-07, 10:03 PM
Over the next 5 billion years, Sol will burn steadily hotter, until it reaches the end of its main sequence and becomes a red giant.

Long before that time is up...long before even the 250 million year time frame you are discussing, earth will have grown far too hot to sustain life as we know it. I forget how long now, but I seem to remember it being on the scale of a hundred million years or so.

I was actually under the impression it was closer to a billion years. If it is only 250 million, we should feel honoured to be part of the last, or second last group of animals to ever dominate the planet.

AKA_Bait
2008-03-07, 10:16 PM
I was actually under the impression it was closer to a billion years. If it is only 250 million, we should feel honoured to be part of the last, or second last group of animals to ever dominate the planet.

Personally, I'm hoping for last and that some of us get out of dodge first. Not that I expect it.

Of course, perhaps we could end up with some magical vancian scenario (I'm sorry, I've just been reading Vance...)

Emperor Tippy
2008-03-07, 10:37 PM
Personally, I'm hoping for last and that some of us get out of dodge first. Not that I expect it.

Of course, perhaps we could end up with some magical vancian scenario (I'm sorry, I've just been reading Vance...)

If we don't kill ourselves off within the next hundred years or so humanity as a species will survive. If we were inclined we could have a self sustaining colony on mars inside of 10 years. Same with the moon. And Venus.

Hell if we really wanted to we could send off ships to colonize other worlds. Although that would mean generational ships and a 50+ year trip.

And once humanity is off Earth with are immune to most things. And once we are out of the Sol system we are safe from everything as a species (unless FTL travel becomes possible, if that happens some plagues and bio weapons might stand a chance).

Rutee
2008-03-07, 10:42 PM
Personally, I'm hoping for last and that some of us get out of dodge first. Not that I expect it.
I would. Look at how far we've gone after a measly what, 30,000 years?

FlyMolo
2008-03-07, 10:56 PM
I would. Look at how far we've gone after a measly what, 30,000 years?

Trouble is, now we're up against Physics. And that's a beast. Because it may not be possible to travel faster than light. Ever. Faster computers, nanotech, etc etc might be possible eventually, but faster than light travel is only a chance, even given indefinite time.

But after 250 million years, you aren't going to find anything that's not buried. Fossils will be pervasive. Bits of pottery underground, Concrete. Assuming it's not subducted, of course. But concrete, with the rebar rusted out and buried could survive for 250 million years. Only fossilized and buried in rock, though.

Doomsy
2008-03-08, 12:28 AM
It really depends on what we left behind to maintain the things we made. A nanotech colony with a dumb or fully functional AI could have mindlessly (or with utter boredom after the first few million years) maintained any number of things by itself. Otherwise, yeah. 250 million years is WAY too large a timeframe for much of anything to have survived save for space tech. Maybe a partial Dyson sphere, etc - imagine a night sky with NO stars save for the planets, except in certain areas.

CthulhuM
2008-03-08, 02:59 AM
Trouble is, now we're up against Physics. And that's a beast. Because it may not be possible to travel faster than light. Ever. Faster computers, nanotech, etc etc might be possible eventually, but faster than light travel is only a chance, even given indefinite time.

Well, even given that FTL travel is impossible, that doesn't mean galactic colonization is also impossible. Combine some sort of mind uploading (http://en.wikipedia.org/wiki/Mind_uploading) technology with von Neumann probes (http://en.wikipedia.org/wiki/Self-replicating_spacecraft) and you could easily seed the galaxy with human, or at least posthuman, life, even if it involves interstellar trips that take hundreds or thousands of years.

Obviously "easily" is a relative term here.

Oh, and, on another note, wikipedia puts the point at which Earth will grow too hot to support current forms of life at about 900 million years from now, though obviously there could be some incremental increases in temperature between now and then.

Neutrino
2008-03-08, 08:30 AM
And once humanity is off Earth with are immune to most things. And once we are out of the Sol system we are safe from everything as a species (unless FTL travel becomes possible, if that happens some plagues and bio weapons might stand a chance).

Actually, there are quite a few things that are capable of terminating a small, interstellar empire. If two neutron stars were to collide or a supernova occur nearby, for instance, humanity's burgeoning little empire would be annihilated.

Of course, if we have FTL, it's a whole different story. There is absolutely nothing you cannot outrun so a supernova or neutron star collision, while probably quite deadly for anyone who doesn't happen to possess a superluminal ship, won't mean the end of humanity.

Talya
2008-03-08, 09:42 AM
Because it may not be possible to travel faster than light.

It is not possible to travel faster than light. That's already proven.

However, it's also fairly well proven that one can create "shortcuts" through space and time. The chance is not that we'll find a way to move faster than light, because that can't be done. The chance is that we'll learn to do artificially what we already know happens naturally - curving ("Warping") space so that we've got a shorter route to travel.


As for other things that can kill a small interstellar civilization, a gamma ray burst would still make short work of us.

Rutee
2008-03-08, 09:55 AM
Trouble is, now we're up against Physics. And that's a beast. Because it may not be possible to travel faster than light. Ever. Faster computers, nanotech, etc etc might be possible eventually, but faster than light travel is only a chance, even given indefinite time.

When has humanity not been facing physics?

Emperor Tippy
2008-03-08, 02:48 PM
It is not possible to travel faster than light. That's already proven.

However, it's also fairly well proven that one can create "shortcuts" through space and time. The chance is not that we'll find a way to move faster than light, because that can't be done. The chance is that we'll learn to do artificially what we already know happens naturally - curving ("Warping") space so that we've got a shorter route to travel.

Actually if causality is true as currently written no version of FTL travel (even wormholes and hyperspace and the like) is possible. But no one has proven causality (and it won't be disproven until we get FTL travel or communications).

Talya
2008-03-08, 03:48 PM
Causality is already partially untrue, it started that way.

Gravity (caused by the bending of space around massive objects) is not subject to the limits of lightspeed. Changes in gravitational fields affect all objects affected by them instantly.

Emperor Tippy
2008-03-08, 03:52 PM
Gravity (caused by the bending of space around massive objects) is not subject to the limits of lightspeed. Changes in gravitational fields affect all objects affected by them instantly.

Got a reference? I have heard both that gravity is light speed limited and that it isn't light speed limited from people who should know what they are talking about. If gravity has actually been proven to be ftl well then that solves a big problem.

Talya
2008-03-08, 04:33 PM
Got a reference? I have heard both that gravity is light speed limited and that it isn't light speed limited from people who should know what they are talking about. If gravity has actually been proven to be ftl well then that solves a big problem.

Several. It's a bit disputed, but the general consensus is that gravity propagates instantly, as Isaac Newton predicted centuries ago. A few years ago a couple scientists claimed to have proven that Gravity propagates at the speed of light, but peer review didn't agree with them.

http://metaresearch.org/cosmology/speed_of_gravity.asp
http://metaresearch.org/cosmology/gravity/speed_limit.asp
http://www.space.com/scienceastronomy/gravity_speed_030116.html
http://math.ucr.edu/home/baez/physics/Relativity/GR/grav_speed.html

Emperor Tippy
2008-03-08, 04:57 PM
Several. It's a bit disputed, but the general consensus is that gravity propagates instantly, as Isaac Newton predicted centuries ago. A few years ago a couple scientists claimed to have proven that Gravity propagates at the speed of light, but peer review didn't agree with them.

http://metaresearch.org/cosmology/speed_of_gravity.asp
http://metaresearch.org/cosmology/gravity/speed_limit.asp
http://www.space.com/scienceastronomy/gravity_speed_030116.html
http://math.ucr.edu/home/baez/physics/Relativity/GR/grav_speed.html

Again, its still very disputed. If gravity propagates FTl it ****s up General Relativity in a big way. Experimental evidence has been claimed by both sides to support their position but as far as I know, no definitive answer or consensus has emerged.

I am personally against causality (at least the its impossible to send information FTL in any way) but its not a decided issue.

Greenfaun
2008-03-08, 09:23 PM
First, I just want to say, this is such a cool thread. Hooray for unmitigated geekery.

Next: What about gold? Barring Aqua Regia, it doesn't really react with anything. It's highly susceptible to erosion and reshaping, of course, but if the planet hasn't been inhabited in the meantime, an archaeological dig might unearth gold bars that still have the bank marks of modern financial institution stamped into them. Or not, 250 million is really a long time...

Speaking of which, to the OP, is there a reason it's 250 million specifically? 250 thousand would be enough to completely wipe surface features clean of marks of civilization, and a lot of evolution to happen on whatever's left around, but there could still be a few ruins and monuments and physical traces. 250 million will mean animals will be biologically unrecognizeable, and practically nothing will realistically have survived to give you the "Oh crap, it's earth!" moment.

Yahzi
2008-03-09, 01:39 PM
No trace of humanity would be left on earth.

Now in space is a potentially different story.
I think the only thing left in 250 million years would be the remains of the moon landings.

Unless they got hit by a meteor.