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Ask HN: If we woke up tomorrow and...

56 pointsby ftseabout 16 years ago
If we woke up tomorrow and all technology had gone, assuming we could still make a fire, how long would it take to get back to where we are now?

25 comments

pgabout 16 years ago
Despite the generally frivolous answers, this is an interesting question and one I often wonder about. What turns out to take up all the time if we want to reproduce where we are now? Presumably the optimal plan is to spend practically all your effort on machine tools.<p>It would be interesting to be able to figure out what would be the best benchmark of progress. Would it be the precision with which you could machine metal? That might do up to about 1900.<p>It might turn out that most of the time was spent on something nontechnical, like moving stuff from place to place before you'd developed fast ways of doing that. So maybe in practice the most important benchmark would be how fast you could move stuff.<p>Reproducing where we are now would in some ways be harder than getting here was. E.g. the most accessible coal and mineral deposits used to be sitting right on the surface, but now those are gone.
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jfoutzabout 16 years ago
I assume every artifact made by man disappears instantly? No books, no canned food, no clothes. Everyone i know would die in a week. My grandma grew up very poor in the dustbowl. She would have a chance, but it's cold at night.<p>So, you're left with people who can recreate their tools in a few days, and don't really need what they have. the !Kung in africa? There's probably 20,000 people in the world like that. Expansion around the globe would likely happen as fast as the first time. 100k years?<p>I think teching back up would take a lot longer. The easy to get natural resources are gone. 100k years aren't really enough for plants to turn back into oil. Maybe really big earthquakes would bring metals to the surface. Once upon a time there were black puddles of oil on the ground. Now, we have to pump saltwater into deep reserves to get the oil out. I suppose there's plenty of easy to reach coal. I don't know much about copper mines, they always look very deep to me. perhaps there is a lot of easy to get surface copper, just not in high enough concentrations to make it worthwhile to mine.
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mcavabout 16 years ago
Long enough that most of humanity would die very quickly. Without tools to grow food to satisfy our current population, we couldn't make enough. Couple that with lack of heating for cold regions, general lack of knowledge of survival skills, and the realization that we must first get <i>metal</i> before we can even create decent tools... I'd say we'd be goners.
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noodleabout 16 years ago
i think you should clarify more. for example:<p>do we still have the knowledge but have no material technological items? do we still have the stuff but no knowledge? are we being impeded by some sort of magical force? are there dragons?
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pavelludiqabout 16 years ago
At first i would be concerned with not freezing to death and finding food, I'll leave technological advancement for the better days.<p>You see, we started to develop technologies only after we had people who could afford not to have to kill their own food, so they had some free time to make now tools or have new ideas. cave men weren't stupid, they just didn't have any spare time to waste.
gcheongabout 16 years ago
Do you have an interview at Google or Microsoft?
electromagneticabout 16 years ago
Well I suppose the bigger question is, does everything the technology created go away too?<p>Technology built everything, but do all our houses disappear or just all the wiring and plumbing and crap? Because if the house goes, then surely so should all the people who were brought about by technology.<p>Realistically there would be approximately (assuming the max for 10,000 years ago) about 10 million people on the planet. If so, with the distribution spread throughout the world then I think if humanity were born with our present knowledge I think we would do rather well, presuming we were swapped out with the Cro-Magnon. I bet about 50% of the people would probably die off within the first decade just through lack of knowledge (again presuming even IQ and knowledge distribution), but if people managed to start bringing back technology I think we could advance things pretty quick.<p>I mean one person with the knowledge of how to make steel and devoted their life to teaching everyone how to make advanced tools, well we'd have skipped 9,800 years in the space of maybe 50.<p>So I suppose it's all in how it would happen and then a large handful of random chance and human nature. I mean if the one guy who remembered how to build a blast forge, also knew how to make gun powder (I know the principle on how to build both) decided to instead of helping the world decided to build a machine gun and build his own country then it could all end when someone usurped him without the knowledge to build tools or weapons.
ytersabout 16 years ago
One big problem is that we need working technology to access much of our technical knowledge.
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dotmatrixabout 16 years ago
We still have the knowledge, so assuming that knowledge is utilized i guess you could answer that question by simply reverse engineering the amount of time it took to obtain the knowledge of achieving a significant process and then determine from that point how long did it take to implement the solution. Since you would be implementing the solution only you would then need to know how many key solutions are you re building and you could figure this question out quite easily.
stavrianosabout 16 years ago
Seems to me that there are two ways it could go, depending on how you take the question.<p>If when all the tech disappears the resources reappear, I'd say it doesn't take too long at all. Maybe ten years, maybe a hundred, maybe a thousand, but nothing more than that. This is a sort of "If people with modern knowledge fall back in time" scenario.<p>On the other hand, if the resources aren't available, ie all the iron that's been mined over the last hundred years is simply <i>gone</i> then we'd be pretty boned, and would probably go extinct. This is more of a post-apocalyptic scenario, except you can't even mine the I-beams out of old skyscrapers, but all the cheaply accessible metal's been mined anyways so your civilization simply can't advance past the bronze age (or wherever you manage to scrape it up to). We'd be like the australian aborigines, who lived for (if wikipedia is to be believed) an astronomical 40000 years on the continent without developing anything more sophisticated than the boomerang.
nixmeabout 16 years ago
Are you asking this question in reference to last night's Battlestar Galactica finale? It was somewhat surprising to see everyone give up technology so easily and start anew with just clothing, some food, and their own language. But I guess being cooped up in those ships for that long and seeing how the abuse of technology led them to such events could have that effect.<p>To answer your question, it's hard to guess. Without medical or agricultural technology, I think most of our current population would die out. The rest would war over the remnants of societal structure. Technical progress, as we see it, would take a long time to begin -- primarily dependent on stability. There are too many unpredictable events that would alter the length of time before returning to stability and our current standards.
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brianobushabout 16 years ago
funny thing was just the other day I was showing my children how to make fire with two sticks. Didn't work. Father failure, though they did understand the idea of friction and the result: heat. Now, my second attempt is using a boot lace with bow (from curved stick) to turn a wood axle with a top brace. Makes smoke, but no fire yet. Somehow, this was much easier when I was younger. However, my point is the basic skills are just as important as the knowledge.
cool-RRabout 16 years ago
I think it's a very interesting question.<p>I would say three to five years. In my opinion, technological tools are overrated. Most things can be built by hand using common materials.<p>Actually, it would be a very cool project! Take a bunch of hackers. Set up an isolated camp for them in a remote area. There will be no technology there, but there will be plenty of edible plants, fresh water, and some medical supplies. The hackers will be supplied with a sample of every raw material that Earth has to offer. And when I say raw, I mean, for example, iron ore. Have video cameras all around the place to make sure they are not bringing technology from anywhere. Measure how long it takes them to build, say a computer. I think it will be less than a year. (The reason I answered 3-5 years to the main question is because in the situation you described most humans will be busy fighting each other, and hackers will have less time to devote to rebuilding technology.)
kellishaverabout 16 years ago
I think you would see a large drop in population before we were able to rebuild. Population growth only occurs when the technology can support it.<p>If we were starting over without any of the knowledge we have now, then it seems reasonable to assume that it would take roughly the same amount of time.<p>If we had history to look back on, then maybe we would be looking at a few hundred years instead of a few thousand.<p>I think the more interesting question is, if we had the knowledge of our past history to look back on, what would we do differently? Would we be more green from the start, for instance? A lot of the problems with adapting to green tech today isn't that the technology is necessarily so knew and unknown, it's that well-established infrastructures and systems are in place that are implemented on vastly different technologies and the cost/logistics of replacing them is prohibitive.
baddoxabout 16 years ago
If every piece of human technology disappeared, I would probably die in a few seconds, since I sleep on the 7th hour.
cmosabout 16 years ago
Now that we have all witnessed the greatness that is online porn, probably not that long.
kenverabout 16 years ago
If we woke up and all the technology was gone, would we want to get back to where we are now...a second time around would be a good chance to fix/improve stuff.
tesseractabout 16 years ago
You'd hopefully get pretty far while current experts are still alive. Otherwise, you'd better at least have a plan for getting printing and libraries up and running pretty darn quickly so they can leave instructions for the next generation...
geuisabout 16 years ago
Was this somehow inspired by the BSG finale?<p>However, I find this kind of question fascinating. This question is posited in the book Marrow, and it takes a very advanced society about 5000 years to get back to where they were.<p>I think the situation right away would work more or less like this. Within the first few weeks to months, nasty. We're literally talking about BILLIONS of people that will starve to death within a matter of several months.<p>Based on your scenario, we're not looking at instantly restored nature. Vast areas of the world would suddenly be large, vacant, barren land where the cities were. Places that were verdant farm land before being paved over by roads, cities, and suburbs are likely to be nutrient starved and unfarmable for many years.<p>You would immediately have millions of people moving out into surviving "wilderness" areas. Trees burning, wild animals being hunted for food. I'm mainly thinking of the U.S., but the ideas apply to most other industrialized countries. "Third world" and agrarian societies might actually fair better. We're talking about the utter decimation of many remaining "protected" species. Suddenly removing everything humans have built, at this point in history, would seriously fuck what's left of nature on the land. On the other hand, humans would no longer have immediate access to the deep ocean. Given the results of ocean recovery in protected areas in recent years, its encouraging to think that many threatened and endangered species and ecosystems would immediately start recovering.<p>The next important thing to take into account is culture and religion. There will likely be surviving populations worldwide that represent the varieties of cultures and religions that we already have. In small pockets, you might find members of the intelligentsia trying to recreate primitive paper as soon as possible, to re-record as much general knowledge as they can. In other parts of the world, particularly the Muslim populations, there will be a religious fervor and general destruction of any remaining advanced knowledge. This will also happen in much of America, due to our retarded Evangelican populations. We might actually find more preservation efforts in Europe and Japan, due to their longer-term cultural histories mixed with being extremely modern. I can't say about China, but they have a long history and might also work to preserve knowledge.<p>People are adaptable, and anything short of a global disaster that fucks the basic life processes of the world, people will survive. It would likely take several hundred years at a minimum, and at most several thousand, before we saw some resemblance of modern technology re-emerging.<p>However, the only cultural artifacts that people would have is what was created from the morning after, onward. There would be no Pyramids, Stonehenge, Jerusalem, Aztec ruins, or anything. No cave paintings, primitive burials, etc. By saying "all technology", this means that all physical remains of our progress would need to disappear too. We would only be left with our memories. In every graveyard around the world, all caskets would disappear. All pacemakers and artificial joints would be gone from the skeletons. They would also be gone from the living.<p>After a couple of generations without any physical remnants of our civilization's evolution, with no pre-history, our descendants would be completely cut off from their past. They would of course be able to re-learn about evolution over the billions of years of life because fossils won't go anywhere. They could relearn about our own evolution, but only from the biology side of things.<p>I would imagine that future historians would eventually realize their legends of an ancient global civilization might have some credence, even though there is no physical evidence. There would be the tell-tale signs, the footprint, that our technology had even though the tech itself is gone. There would be the atmospheric carbon levels, the concentrations of uranium where reactors and weapons were, and hundreds of other alterations to the physical world that we've made.
raquoabout 16 years ago
So the question is whether the humanity will be able to stabilize before current generation (with the knowledge of technology) will die (including because of age)
knownabout 16 years ago
<a href="http://en.wikipedia.org/wiki/Cast_Away" rel="nofollow">http://en.wikipedia.org/wiki/Cast_Away</a>
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nazgulnarsilabout 16 years ago
I think people speculating in this thread would greatly enjoy Earth Abides by George Stewart.
jodrellblankabout 16 years ago
All technology? I guess we're back at the bottom of the Civilization advances tree, eh? Do you want triremes, maths, militia or granaries?<p>England has ~65 millions of people. Take away all manmade technology (including buildings, tarmac, concrete) and any city would be many square miles of bare earth collapsing into holes where sewers and tunnels and underground trains once were.<p>Within a day or two it would be many square miles of human waste, corpses, mud if it rained, and people making their way to the nearest rivers.<p>Within a couple of weeks, significant fractions of people have starved or died of lack of medical treatment, fighting, illness from river water contaminated with sewage and corpses, etc.<p>OK, you can drink from the river you may not get ill for a while. What can you eat but other people? City areas -&#62; wastelands.<p>Out in the country, farmers with easily harvested crops in season are the best off, until they get looted. With no food stores or shops, animals and current crops will be eaten quickly and that's pretty much that. Good luck surviving on hedgerow food and hunting with no experience and everyone else trying to as well.<p>Some strong willed resourceful people in remote niches will survive (nobody could travel to them very quickly). After a few years we'll see who. Small farms, maybe some farm animals, fast growing trees coming into usable sizes. Levers, (wooden) wheels, barrows, hammers hoes, heaters, cookers, flint/stone axes, they'll be around.<p>Maybe in short order some beach sand melting -&#62; glass jars, glasses. The people who survive are the people who currently live with reduced technology and will be busy staying alive.<p>What then? I don't know. A few decades to a population big enough and connected enough for mass trade, I suppose. By then a similar sort of grind up through metalwork, blacksmithing, banking, debt, economic collapse...<p>What technology could we skip to that would hasten us through such developments? I say at least two hundred years.
jodrellblankabout 16 years ago
On reading the replies, I suddenly remembered this: <a href="http://www.overcomingbias.com/2007/09/planning-fallac.html" rel="nofollow">http://www.overcomingbias.com/2007/09/planning-fallac.html</a><p>My revised estimate for the time it would take to recreate all of history is approximately as long as it took the last time, plus a bit.
jodrellblankabout 16 years ago
The last time a similar topic came up at HN, it was the "what if you time travelled back to the past" question.<p>I didn't think of it in time for that thread, but I wanted to turn the question around: Looking back through history, if we wanted to spot a technologically advanced person appearing in the past and trying to create 'future' technology, what markers should we look for? (and ... has this happened?).