# Can one guy with a duplicator initiate a nuclear apocalypse?

The setting:

• Present day. The country is up to you. Whatever would be easiest.

The guy:

• Highly skilled. Maybe ex-Marine? Special forces? You can have him be "top of his class" at just about anything, but not a genius or a superhuman.
• Has a death wish, but like, for everyone. He knows that he won't come out of this alive, and he doesn't care. He just wants the whole world to burn. Total human extinction if possible.

The duplicator:

• Shaped like a gateway large enough for a car.
• Only works once. Once you hit the button, it stays on, producing the exact same thing over and over, with no option to change what it makes.
• To activate, fill up a car with whatever supplies you want duplicated (i.e. a car containing you, your savings in cash, provisions, C4, guns, and ammunition), then hit the button. From that point on, an endless line of cars driven by clones of you drives out of the gateway at a rate of about 5 per minute.
• All duplicates are created at once, so the duplicate who drives out 4 hours after you hit the button has been driving for 4 hours (they come out of parallel universes; I don't want to get into it). They can refuel and replenish their food supplies in the other universes, so don't worry about that, but their need to sleep might impose time constraints.
• Can be placed anywhere (the limiting factor is where to park all the identical cars). Can't be moved after the button's been pressed.

The question:

• Can this guy and his duplicated army get past a country's defenses and launch their entire nuclear arsenal?

The way I see it, he has a well-coordinated, well-equipped, and talented army that can assemble innocuously in a matter of hours or days, so it seems plausible that he could overpower them before reinforcements arrive. Then again, he doesn't have nuclear codes or any clear way to get them. Does he stand a chance? Are nukes even his best option?

• Comments are not for extended discussion; this conversation has been moved to chat. – L.Dutch - Reinstate Monica Sep 17 '19 at 15:17
• A genius, as defined by Mensa, is someone in the top 2% of the population by IQ. Most people who are "top of their class" in anything academic are likely to pass that bar, so the question contradicts itself. – Peter Taylor Sep 18 '19 at 7:16
• @PeterTaylor: Only if you take the Mensa definition, as opposed to the normal meaning of the word. – Jack Aidley Sep 18 '19 at 14:07
• Is the car bit mandatory? Can we just duplicate something? – Jack Aidley Sep 18 '19 at 14:07
• Gav started as one doomed guy. He finished up as his own galactic demographic. schlockmercenary.fandom.com/wiki/The_Gavs – puppetsock Sep 18 '19 at 20:56

## Make your own, Sorcerers Apprentice style

Pickup truck, guns, ammo, food, radiation suit, 10 7kg Uranium bricks.(Federal government allows you to get 7kg at a time and possess no more than 70 in a calendar year reputable sources may do sales checks and block your shenanigans)

Set this up outside a flooded quarry. Set up pumps to drain the quarry.

As clones come out with their uranium they pile stack it neatly and take up guard duty. Within a few hours the stack will be big enough that the clones will get radiation poisoning while stacking so shut off the pumps and dump bricks over the side. As the water starts to fill the quarry again the reaction speeds up.

Once it really gets going huge radioactive clouds will start circling the planet. It will make Chernobyl look like a wet fart. The only thing that could be done to stop it would be to nuke the pile itself, which would be worse in the short term, but perhaps the surface would be colonizable by mole people in 1000 years instead of 10000.

• FYI: 7 kg limit of Uranium refers to either natural or depleted Uranium. Without enrichment, this operation is not going to succeed. – Alexander Sep 16 '19 at 18:47
• Might wind up asking a spin-off question about it, or maybe figuring out a way for the guy to get half a gram of enriched Uranium in a way that doesn't seem too contrived. At any rate, thanks for telling me how much Uranium a person could buy - I didn't want to look it up and end up on a watch list :P – Gilad M Sep 16 '19 at 19:03
• @Mark as far as I know, no. You can collect a lot of radioactive byproducts from large amount of uranium, but won't get chain reaction, meaning that "abandoned quarry operation" will look much less dramatic. – Alexander Sep 17 '19 at 3:26
• Ordinary uranium will not work for this, it's not really radioactive enough to do anything interesting. – Tomáš Zato - Reinstate Monica Sep 17 '19 at 14:25
• @MongoTheGeek my understanding is that these natural reactions were only able to take place billions of years ago, back when the concentrations of fissile Uranium isotopes were much higher. Nowadays, any natural Uranium will be unable to sustain a chain reaction. – Gilad M Sep 17 '19 at 18:44

Flood a democratic country with nuclear weapons with clones. Make sure each clone gets to be registered as an elector.

Candidate the master as president (or prime minister), and have the clones vote for him. Sure victory.

Once he is in the war room with access to the nuclear suitcase, let him fire it with no mercy. Wait for retaliation.

• Though I considered a number of contingencies, this one never occurred to me. +1 for patience waiting for the clones to come through. – A new normal. Sep 16 '19 at 19:56
• Haha, upvoted for the sheer cheek of it. But I imagine people would start to notice if the population of France or whatever mysteriously doubles and all of the new citizens look the same. :) – Gilad M Sep 16 '19 at 19:57
• @Thucydides true, but once you control the qualified majority of the electors needed for that system, you can run with your own party, no matter what. – L.Dutch - Reinstate Monica Sep 17 '19 at 4:25
• Getting all the clones registered as separate people on the electoral rolls might be a bit tricky, though. You'd also need to fabricate unique ids for each one of them, at the very least, and the existing government might get suspicious if their registered population doubles overnight (and most of the new people look identical)... – Miral Sep 17 '19 at 7:20
• @Miral it doesn’t happen overnight. Only 5 per minute, according to the question. That makes 2,6 million per year, so you need a rather small country to overrun, or, since it ought to have nukes, you have to prepare for some waiting time. So registering them might not be a problem, the first incomers might be infiltrate the administration to ease the registration of the followers. But whether all of them are willing to elect you, after you have forced them to march for several years, is a different question. – Holger Sep 17 '19 at 8:50

Simply throw the gateway into a river.

Let's say there's 2000 cubic meters of water per second flowing out the river. After 12 seconds, there's 4000 cubic meters of flow, after 24 seconds there's 6000 and so on.

As the duplicates are all created at once, there won't be any backpressure reducing the flow.

After a day, you'll have imported 622 cubic kilometers of water. After a year, 82 million cubic kilometers of water. After 8 years and 5.3 billion cubic kilometers of water, Mount Everest would be under water.

Mission accomplished.

Edit: Some people in the comments don't understand how I've arrived at these numbers, so here's how it breaks down:

• The question, at the time I've answered it, doesn't specify a time or length limit for objects passing through the portal, or that the first duplicate has to finish coming out before the second duplicate starts coming out.
• However, it does specify the same thing will be produced over and over, at a rate of about 5 per minute (i.e. 1 every 12 seconds)
• Therefore, if you divert a river with flow $$n$$ cubic meters per second into the portal, at the output, the flow rate after $$t$$ seconds will be $$n*((t/12)+1)$$ i.e. a flow of $$n$$ at zero seconds, $$2n$$ after 12 seconds when the first clone starts emerging from the portal, $$3n$$ after 24 seconds when the second clone also starts emerging, and so on.
• And the cumulative volume after $$u$$ seconds will be the integral of the flow rate - $$\int_0^u n*((t/12)+1) dt = n*u^2/24 + n*u$$
• Hence, if the flow rate $$n=2000$$ cubic meters per second, after 8 years $$u=252288000$$ giving a cumulative volume in cubic meters of $$2000*252288000^2/24 + 2000*252288000 = 5304103416576000000$$
• Divide by $$10^9$$ to get cubic kilometers, and $$10^9$$ again to get billions of cubic kilometers, and you arrive at 5.3 billion cubic kilometers.
• Granted, 2000 cubic meters of water per second is on the high side - but the Hoover dam's spillway has a capacity of $$11,000 m^3/s$$ - and thanks to the exponential, even if you had a more modest 150 cubic meters per second you could still have a meter of sea level rise in a year (resulting in massive food shortages and and population displacement) and Everest under water in less than 90 years
• Ah, so this is the backstory of waterworld. Not everybody killed though. But replace the river with a big stream of something really toxic (in a chem plant or something) or just the dirtyest possible stretch of river perhaps, salt water a plus too. – joojaa Sep 18 '19 at 16:40
• Not how the duplicator works unfortunately. The gateway occupies the same space in all parallel universes, so if one of them is underwater, they all are, including the output gate. No net flow. – Gilad M Sep 18 '19 at 17:30
• Nice idea, but hardly any river gets 2000m³/s through a car-sized portal. – Bergi Sep 18 '19 at 22:58
• @Bergi besides the ridiculous prerequisite of getting 2000m³/s through a car-sized portal, any number of this answer seems to be just invented instead of calculated (it’s hard to believe that someone makes so many mistakes in a row). Even if you manage to produce 2000m³/s of water, it produces only 505km³ in eight years, which Earth would hardly ever notice (a raise in the magnitude of not even a millimeter). – Holger Sep 19 '19 at 8:55
• @Luaan even if you manage this, there’s an older answer already suggesting that, which has been debunked even before this answer was created. I don’t know why this answer saying the same thing got so many upvotes. Perhaps, due to the author’s confidence when presenting the totally wrong, made up numbers… – Holger Sep 19 '19 at 8:59

Why go Nuclear? Just go Toxic!

Ok, so your bad guy wants to kill the world and nukes could do that sort of thing in a hurry. The problem is that it takes enormous amounts of technology, highly specialized know how to make your own, and nukes are the most jealously guarded items in the world.

Toxic stuff, however can be found under your kitchen sink, and acquiring items needed to make some truly nasty stuff could probably done fairly easily in an under the radar manner.

So your badguy does some research and finds out how to get the greatest lethality out of the limiting volume by means of poison. He can do all sorts of nasty twists with this. What will not only kill, but go on killing long after word? What kinds of poisons can be aerosolized and spread over an entire city. I remember the movie "The Rock" where a single rocket would have wiped out a significant chunk of San Francisco. You have a lot of options here. Anyway, he kits out with the maximum lethality per volume.

Next, he sets up in a place with the shadiest shipping possible. I'm talking someplace with a corrupt government and lots and lots of container ships. Each clone gets here, drives on to a container and gets shipped to a different part of the world. Some will simply take off and travel overland, trying to get as far as they can reasonably without getting searched.

At home base, or likely a little way away from the port, because you need to a place for all the clone vehicles, set up a gathering spot for not getting shipped out. Have your clones begin acquiring as many explosive materials as they can. Gasoline, Fertilizer, whatever.

The Containers will get to the destinations. Certain clones will drive to the interior parts of whatever country they get to as best they can.

On a designated day, possibly a couple of weeks after you push the button, you blow everything. Your poison of choice gets released in ports all over the world. Several nasty spots will erupt inside various countries all over. Have your big detonation spot go up somewhere that it will spread as far as possible over populations centers. Have each guy carry clues that he came from someplace his destination hates most. Israeli flags for Muslim Countries, Pakistani flags for India, and so on.

Hopefully, What the poison doesn't kill will trigger the nuclear powers to go after each other.

I am mildly horrified that I came up with this.

EDIT: As an additional Nasty Twist. If feasible, make the aerosolized part from the big boom carry along some sort of sterilization agent. That way if it doesn't kill someone, it renders them unable to have children. That way you get the big die off, followed by the human population not being able to reproduce reliably enough to keep going.

Also, for the guys going inland. Get as close to hospitals as possible. If not hospitals, by first responder stations. Aaaand I'm even more horrified by myself

• Similar to Thexa4's answer, but more coordinated. For someone as skilled as our guy, sure, I could see them poisoning millions, maybe tens of millions this way. Seems amply destructive, but I don't see the ploy of pitting nuclear neighbors against each other working. Namely, poison attacks are not how any of these countries operate, and anyway if you set these up in cities all over the world, it'll be obvious to any Indian, for instance, that Pakistan wasn't responsible. Still, +1 for being the most destructive yet reliable plan so far. – Gilad M Sep 17 '19 at 15:10
• @GiladM so pick a country with lots of enemies (the US maybe), and target the attacks at their enemies, ensuring that at least several are nuclear powers (so for the US you'd target North Korea, Russia, Iran, China, etc). Said enemies will see these coordinated/targeted attacks and note that they are all being targeted and the US and its allies are mysteriously untouched. Cue nuclear retaliation. Cue nuclear re-retaliation. Cue mutual, and likely global, destruction. – Doktor J Sep 17 '19 at 16:59
• I feel like the goal is human extinction. You don't need nuke strikes for that. They would be a welcome addition, but not critical. I edited my answer to add other layers to the destruction, such as sterilization, and another way to maximize casualties – Paul TIKI -Monica come Home Sep 18 '19 at 15:19
• Yeah, that definitely helps the destructive aspect of it. I just want to point out that if you go down the list of answers starting at the most-upvoted, this is the first one that actually works. Not that that matters to anyone else :P – Gilad M Sep 19 '19 at 9:08
• @GiladM Why thank you. – Paul TIKI -Monica come Home Sep 19 '19 at 14:13

step 1: acquire a car load of the most harmful greenhouse gases possible
harmful gases could include:
- Trichlorofluoromethane not only does this deplete the ozone and trap heat 4,600 times more effectively than carbon dioxide but it also breaks down into chlorine gas and is used as a refrigerant which could make it easier to acquire
- Hexalfuoroethane which traps heat 9,200 times more effectively than carbon dioxide and persists 10,000 years
- Nitrous oxide, this may be the easiest to acquire

step 2: release the duplicated gases into the atmosphere
As your replicated car load of compressed greenhouse gases come out of the duplicator release the gases into the atmosphere. These gases will contribute to increasing the average global temperate, increase extreme weather events, melt polar ice caps, raise the sea level, acidify the oceans and cause mass extinctions of oceanic life and ultimately make the Earth uninhabitable until the gases can be broken down.

harmful greenhouse gases reference

• This was brought up in a comment on the question as well, though the idea of using hexafluoroethane instead of CO2 makes it a lot more viable. Let's be generous and say that we can manage to fill the car with 200 lbs of gas (no idea where we get the gas or how it's stored), and then we release it as quickly as the cars come out of the duplicator (5/minute). Even including the factor of 9,200, we still only come out to about half the US's footprint in any given span of time. – Gilad M Sep 17 '19 at 18:32
• Now, that's not nothing - adding 50% to the warming rate contributed by the entire United States is a seriously big deal. But you'd have to keep it going for years for it to significantly speed up climate change, and the government's going to catch on and shut down the duplicator way before that. At the very least, air pollution tests will pick up on it after it's spread throughout the atmosphere, if local health and wildlife issues don't give it away sooner. – Gilad M Sep 17 '19 at 18:36
• @GiladM could avoid localizing the health and wildlife issues by driving the containers some distance away from the duplicator, and with how long some of the greenhouse gases persist you can sit back and know that even if it's shut down after some time the damage has been done – BKlassen Sep 17 '19 at 19:04
• @GiladM Trichlorofluoromethane is a liquid at room temperatures (boiling point is 23.77°C), so it's quite easy to load a car with a metric ton of that stuff. Actually, it would be simpler to set up the ring above a small hill within some large, hot desert, in such a way that anything that comes out immediately drops to shatter on some rock. Activate the portal with as large a container filled with the stuff you can get, and you can get to about 100 tons of the stuff per minute. That'll dwarf even the US endeavors for a warmer climate. – cmaster - reinstate monica Sep 17 '19 at 19:14
• I have to say, this is increasingly looking like the most effective alternative to nuclear weapons. I don't think I'll use it for the simple reason that I envision my character wanting to go out in a blaze of glory rather than making the Earth increasingly uninhabitable over a period of a few hundred years. Still, definitely earns a +1 from me. – Gilad M Sep 17 '19 at 19:23

Potentially yes, but it needs more of the knowledge and less of an army.

Nuclear weapons have several layers of protection. It is not enough to capture a nuke to be able to detonate it, and not enough to capture an entire nuclear facility to launch a missile. Intruders need to know exactly how to circumvent all security to succeed with their plan. An army of marines can potentially overrun a major military base, but still not able to launch a single missile.

So I think this has to be a specialist who worked with nuclear security rather than plain vanilla marine. He'd better to infiltrate the facility in "Mission Impossible"-style operation rather than try to engage in an all-out war.

• The point of Permissive Action Links is to prevent this sort of thing: even if Ye Olde Bad Guye takes over an entire missile wing, or bomber wing, eats the brains of everyone present, and goes "wing attack plan R!", the PALs won't let the bombs go boom without proper authorization from above. – Tangurena Sep 16 '19 at 19:58
• Given how there have been known cases of default passwords never changed on such devices... – rackandboneman Sep 17 '19 at 20:28
• @Tangurena and not every country with nukes uses a PAL system. And within those countries not all nukes may use them. ' – jwenting Sep 19 '19 at 7:30

Aren't you overcomplicating things? Anything you add to infinity onto this planet will destroy everything. Add a cubic meter of water infinitely over and over, and all life will drown (slowly) ending up in WaterWorld, the plot and horrible direction of which will drive whatever surviving sentient life to suicide. Or speed it up with a cubic meter of poison.

Anyway the logistics are horrible, a car every 12sec 24/7 will cause a gigantic traffic jam a few hundred miles down the road... These duplicates have all had the same instruction (so they cannot take up their correct positions unless there's a recursive algorithm -- say "follow the guy ahead"). If mental state is copied along it's going to fail because they have in their head load of roles for the 'drones' but think they're the master/architect of the plan themselves.

EDIT@comments: I'm trying to start with disclosing clearly why I inherently dislike the scenario, as ANYTHING you reproduce infinitely will screw up everything (water or some semi-liquid pollutant is easy as unstoppable in this scenario; let it flow no logistics needed). Then I point out that anything you try in an organized manner is going to require rules (like fish schools or bird flocks, not that hard) that have little or no plan written in them as catastrophic jams will occur; which are things the other answers skip over. So I don't really see the two disparate parts as grounds for downvotes (but hey, I may be biased =D), they're my scepticism on the scenario.

The 'just add stuff' approach is somewhat similar to the 'grey goo nanobot apocalypse' (where it's finite but just limited to 'everything now on earth'), or the Borg assimilating all they touch.

• It's funny how you suggest that this is a simple matter of dumping infinity things onto Earth, then immediately describe all the logistic issues that make moving infinity things from one place to another so difficult. Gotta downvote, sorry, none of this answers the question. – Gilad M Sep 17 '19 at 10:28
• @GiladM Moving millions of vehicles around is incredibly difficult. Moving lots of water is dead simple. It moves itself to the lowest available spot. Put the portal on the side of a tall mountain, and more or less the whole world will be flooded before the portal is underwater and rendered ineffective. Though it would probably be bombed out of existence well before that happened. – nasch Sep 17 '19 at 15:07
• @nasch: An even easier way exists due to the portal's property "cannot be moved once activated". Drop it out of an airplane, and press the button while doing so. It will stay in mid-air. No trouble managing stuff that is produced. – Damon Sep 17 '19 at 15:29
• @Damon Possibly, depending on exactly how the "cannot be moved" works. – nasch Sep 17 '19 at 15:32
• Sea level would very slowly but steadily rise the world over with no obvious cause. If the base's location were carefully chosen, it should be untraceable to the outside world. At 5 cubic meters a minute after a year you would have 2.628 million m^3. By my rough calculations this would amount to about 0.7 x10^-6 m increase in sea levels annually. So the facility would only have to run for a thousand years to get you a millimeter. a million years for a meter. Turns out the world is a big place and 1 cubic meter pretty insignificant. – Mr.Mindor Sep 17 '19 at 22:23

TL;DR You won't even need nukes

I'm going to frame this answer based on the characteristics of the portal described by your linked question, namely:

A solid material has been discovered that, when shaped into a ring and activated (by lowering its temperature below some critical point, let's say), it forms a parallel universe on the other side. This isn't a gateway into an existing alternate universe, but rather a duplicate of the host universe

I'm going to assume some dimensions: the portal a rectangular ring 76 inches wide and 64 inches high on the inside with a thickness of 4 inches added to the outer dimensions, and the vehicle being driven through the portal being 190 inches long, 72 inches wide, and 60 inches high. The actual dimensions are not really important, but this is just a starting point to establish feasibility. You said "car" but I will assume you mean any vehicle roughly the size of a car so I will assume a flat bed vehicle with minimal wall and roof curvature for maximum interior volume. There will be as much lightweight armor inside (so as to not be noticeable) as possible to protect the interior contents from small weapons fire. The vehicles would be painted a boring color so as to not attract attention. It would have tires for off-road travel so it would not need to stay on paved roads. The vehicle will have a modified extra large gas tank for extended range. For convenience, I will call the material "parallelium".

The vehicle would be loaded with:

• villain in lightweight body armour
• large dollar amount of cash and precious metals
• inactive parallelium pre-shaped ring of the specified size (outer dimensions of 80 inches by 68 inches. The 68 inch height will be laid across the bed to fit within the 72 inch constraint while the 80 inch width will fit comfortable front to back.
• compressed coolant sufficient to active the ring
• a full tank of fuel
• enough weapons and ammunition for major assualt
• remaining space filled with high explosives rigged to explode in one of three ways:
• remote wireless trigger
• dead man's switch when villain becomes incapacitated
• upon any kind of tampering

At 5 vehicles per minute this is less than 1mph exit speed which will give each vehicle plenty of time to speed away to another location before the next one full emerges.

The initial setup would occur in a large vacant area far enough away from any city so as to not initially attract any attention even when a large number of vehicles have come out of the portal, but also located in a location "centrally" located in the world.

In phase one, as each vehicle emerges, it will immediately drive to a designated area based on its order. First priority would be get vehicles to each continent, which most likely would require transport on some kind of ship. If needed, it can be pre-arranged to have some of the components acquired and/or moved ahead of time to make things go more smoothly. For instance, it may be difficult to transport an explosive laden vehicle across the ocean unless one charters or buys an entire cargo vessel and/or greases a few palms. But if the explosives, weapons, etc. are obtained on the same continent and then staged, it will make this part easier. Also, by getting an initial distribution of as many vehicles as possible as far away from each other as possible we avoid potential chain reactions should one vehicle explode ahead of schedule, as well as making it difficult to stop enough vehicles to offset the exponential increase rate.

There are around 432,000 vehicles emerging per day. If we waited up to 30 days for duplication centers to be established around the world, that would mean we need room for almost 13,000,000 cars if we are waiting to launch our attack until everything is in place which alone would take at least 50 square miles. This is only 7 miles on a side, and is also the worst case, so plenty of planning would need to be done to determine the exact logistics of where and when to send vehicles.

In phase 2 part of which can be concurrent with phase 1, as each vehicle emerges, it will immediately pair with the next or previous vehicle and drive a pre-determined distance away from the portal based on the order it emerges in. When each pair of vehicles reaches their destination, one will immediately unload and set up one of the portals, and unload one of the cooling tanks to ready activating it. The second vehicle would then activate it, duplicating itself and the original contents.

This process would create an exponentially increasing number of vehicles, with the number of vehicles doubling every cycle. The length of each cycle would increase linearly as subsequent generations needed to drive further away to an empty area to avoid running out of space too quick, but each established gateway would continue pumping out more vehicles able to either set up new gateways or proceed with other activities.

In phase 3, which might ideally start after phase 1 was complete, but which would be concurrent with phase 2, each individual vehicle would enter rampage mode, with the driver seeking to inflict maximum damage. The ultimate end of each vehicle would be the same, a massive explosion capable of at least leveling a large building.

Now to run some numbers. Suppose we amass only 100 vehicles in a particular region in phase 1, and in phase 2 have a 5 minute duplication time, which includes driving a least one minute away (one mile at 60mph), setting up the duplicator, and then producing the first duplicate. After 5 minutes we will have 200 vehicles from the first duplication, with an additional 500 vehicles per minute from the first set of duplicators. At the 10 minute mark we will have 2700 vehicles from the initial vehicles and the first duplicators, plus another 400 vehicles from the second duplication, with an additional 1000 vehicles per minute from the second set of duplicators. At the one hour mark we will have over 200,000 vehicles just from the first 12 generations of duplicators, plus millions more from additional duplicates they generated, plus another 1,000,000 vehicles per minute from the current set of 200,000 gateways already established.

From this it should be pretty obvious that no army on earth is going to be able to stop this. By completing a distribution in phase 1 so we have duplicators spread across the world before phase 3 starts, this means that one the rampages begin, it is too late for anybody to do anything.

Now phase 4 happens when the number of vehicles becomes so numerous that phase 3 becomes difficult. What happens when you have millions of vehicles exploding all over the place, destroying infrastructure, and so forth? More vehicles are getting pumped out, and now they have nothing to do but get as far away from the replication point as possible before exploding. Now being able to drive off-road is more important, because these explosions are now going to start destroying the earth itself. Tens of millions, hundreds of millions of explosions, until the surface of the earth is completely turned into craters as deep as they can go, and it will not stop until every last vehicle is destroyed simply by the fact that there is no place left to go for any vehicle except to explodes at the gateway that it just came out of, which is just outside the blast radius of the next gateway, and the entire surface of the earth is covered with gateways in this fashion. Even being at sea is not a defense, because some of our vehicles can take over every container ship in the world and cruise to every island and set up more duplication centers and wipe them out, keeping as many copies in ships across the world for as long as necessary to make sure the earth is reduced to rubble as much as possible and not a single living thing is left alive.

It's even possible that this will destroy not only the universe, but all the parallel universes we just created, because where else will all those infinite vehicles go?

• I appreciate the thought that went into this, but there's a reason I didn't explain the parallel universes again here. I didn't want this to devolve into a discussion about technicalities. Long story short, the "duplicator" pulls copies from parallel universes by linking thousands of universes and having all the copies crowd into one of them. So in 99.999% of cases, when the portal opens, you just walk inside and disappear, and only in the other 0.001% do thousands of you come out. An exponential chain of this means this plan is only infinitesimally likely to work. – Gilad M Sep 17 '19 at 7:31
• 5 per minute makes 5x60 for an hour or 5x60x24 a day... I can't really follow how you get to that 432.000 vehicles a day result. – Zaibis Sep 17 '19 at 8:50
• Ok, continuing to read, you completely lost me... "one will immediately unload and set up one of the portals" Why are you talking about multiple portals? Didn't OP explicitly state that there is only one portal in existence? So is this a frame challange? You should make that more clear than. – Zaibis Sep 17 '19 at 8:52
• @GiladM I assume you're indicating that, because the "first generation" of clones were all sucked from all the parallel universes, even if they successfully set up their own duplicators, said duplicators would most likely not have any parallel universes left to pull from because the first duplicator has grabbed them all? – Doktor J Sep 17 '19 at 16:56
• @Michael it's not clear to me that there are an infinite number to start with. Looking at their parallel universes question, it seems they are leaning toward only permitting a finite number of parallel universes, and if the duplicator smashes all these together and takes from them, then there are none left for another duplicator to take from. – Doktor J Sep 17 '19 at 18:04

To trigger a nuclear apocalypse, the guy doesn't need to trigger all the nukes himself. Triggering a few to exploit existing fault lines is enough to watch everyone destroy themselves. For example - India Pakistan, India China, US China, US North Korea, US Russia, Israel Iran (rumored to be working on nukes).

At the rate of 5 per minute, duplicator can produce 7200 clones per day. However, things like credit card, identity card etc tie into an external database (of banks, govt), so they won't work. So, your guy needs to go old school, with cash etc :P.

Since he can have the right knowledge, he can be someone who already knows how to compromise a nuke carrying submarine with the right number of clones. This is possible if he knows schedule etc of the sub's stops, and knows enough to operate and flee away with it, and launch the nukes.

This way, he is armed, and mobile.

Once done, all that is needed is to trigger nuclear strikes on individual cities, and watch the world destroy itself.

Of course, the best place for a duplicator in such a case will be some hidden location within the sub itself.

However, if you want the guy to physically grab all the nukes and trigger them, that would be a difficult task - there are supposedly 8 nuclear armed countries, with over 16000+ warheads as per wikipedia. even if these are stored 10 per location, you would have 1600 really strongly defended locations, busting which will be an impossible feat given the constraints involved (intelligence, logistics, coordination, etc)

• Yeah, the goal from the start was launching only one country's nukes and hoping nuclear war follows. The hard part is the "launch the first nuke" part - I'm not sure how feasible it is for someone to take over a nuclear sub and have the authorization to launch. (also fyi at 5/minute it's 5760/day not 288) – Gilad M Sep 16 '19 at 16:35
• @GiladM Thanks, I calculated basis 1 per 5 minute :). As for getting hold of nuclear subs, hollywood movies have shown it a few time, so I guess its upto the narrative that is being built around it. – mu 無 Sep 16 '19 at 16:37
• Wait, no, it's 7200 :P I misclicked, must have done the calculation for 4/minute. Whatever, the exact number isn't super important. – Gilad M Sep 16 '19 at 16:57
• @GiladM And I lazily did not calculate it either :D – mu 無 Sep 16 '19 at 17:00
• Keep in mind, cash has a serial number aswell, what might at some point discovered that there are quite some duplicates of specific numbers. – Zaibis Sep 18 '19 at 8:09

I don't think you need your own uranium or nuclear device to raise the nuclear global meltdown you want. Probably just by taking down the radars and defenses of some country with your army of clones, you can get its panicky/vengative leader to push the button.

I guess this is what you want:

• Deploy your duplicator in Pakistan.
• Amass your army. Probably nobody will notice you until it's large enough for your purpose.
• Kill all radar/AA bases that defend the country from ballistic missiles from India.
• Continue to Pakistan's missile bases.
• Pakistan leader panicks, thinking India will follow with a nuclear strike.
• So Pakistan shoots first, their nuclear bombs to India.
• India, of course, retaliates.
• All the world sees how nuclear fallout will start soon producing massive exodus from India, West China and the rest of South Asia to East China.
• All the world, specially China, sees how the economy of China will crumble.
• You planted enough false, plausible proof of involvement of the USA in the attacks to Pakistan...
• for China to think that the USA started the conflict to indirectly destroy China.
• So China shoots their everything to the USA.
• USA retaliates China, and also Russia, because otherwise Russia could survive the USA.
• Russia gladly accepts the invitation to the party, and attacks China, USA, and every other country hosting USA forces and NATO members...

It still feels a bit tricky to pull all of it off, though.

• Seems unlikely that Pakistan would launch nukes unless it had more concrete evidence that India would attack it. Other than that, I like it. India and Pakistan are the ideal starting point, given the continuous tension between them and the number of nukes they both have. Perhaps it would be possible to dismantle one of their nuclear warning infrastructures while planting ample evidence that the other was at fault. It's just getting one of them to pull the trigger that's the issue. – Gilad M Sep 17 '19 at 10:36
• @GiladM: Of the three countries forming the first three dominoes, Pakistan would be the one to push on though; both India and China have explicitly declared a no-first-use policy (they won't use nukes unless someone else uses them first), while Pakistan has stated it would use them if invaded or attacked (which is one of the most aggressive postures of any nuclear state; most others without no-first-use doctrine say they'd use them in cases of existential threat to themselves or their allies, or in response to non-nuclear WMD deployment). Pakistan is the most trigger happy in official policy. – ShadowRanger Sep 18 '19 at 3:01

Nuclear apocalypse likely isn't your best option, it's hard to pull off. A way more effective method would be to pick a few of the elements mentioned in the Things I Won't Work With series. Acquire a bit of that, drive through and release. After a while the environment will likely automatically ignite the duplicates. (Which also solves the car parking problem)

Assuming the duplicator keeps working you'll make everything pretty uninhabitable.

• The issue is a logistic one. How many people will this really hurt before some government figures out what your doing, arrests/kills the clones and destroys your duplicator? I just can't really see this causing destruction on the scale of the entire human race the way a nuclear war might. – Gilad M Sep 17 '19 at 10:43
• Yes, the assumption was that the duplicator would keep functioning. If it's easy to destroy the proposed approach would destroy it on its own pretty quickly. – Thexa4 Sep 17 '19 at 11:04

Alright, here's my own answer. It pulls ideas from MongoTheGeek, dmcontador, and Paul TIKI. Thanks to all of you, this kind of variety of inspirations was exactly what I was hoping for.

Step 1: Break my own rules

The guy needs to start out with knowledge of how to build an atomic weapon, a dirty bomb at least. He also needs to start out with a small amount (~1g) of weapons-grade Uranium. I didn't say he could have those things, so, yeah, I'm cheating a bit. But I think in the context of what I'm writing, I could have him be a UN nuclear inspector / specialist, which pushes both of these starting conditions into the realm of possibility.

Step 2: Duplicate money and Uranium

He hides out somewhere in India and turns on the duplicator. After a week of discreetly copying himself, he could have enough resources for a dozen atomic bombs. He packs them up in vans and has clones drive them out to population centers.

Step 3: Nuclear war

He detonates all the bombs within minutes of each other. The radiation detection systems all over the country confirm nuclear strikes, and India launches a counterattack against Pakistan. Pakistan retaliates. Proportionate response is out the window, since those first dozen strikes, properly positioned, could have killed hundreds of millions of people.

Step 4: Fallout

It seems reasonable that this would lead to both countries deploying almost their entire nuclear arsenals. India's first attack would likely involve at least 20 missiles, and when Pakistan fired back, they'd see it as an escalation. The resulting cloud of dust would plunge the Earth into a decade-long nuclear winter, and the resulting food shortage would likely result in the loss of 40-90% of all human life.

...

• Whats wrong with duplicating coke and h.... – joojaa Sep 17 '19 at 16:04

Start by destroying the financial markets

Clone gold and stockpile. Ditto for diamonds, other precious metals and gems. Suddenly dumping thousands of tons on the market all at once causes the markets to collapse. All the world currencies devalue and gold stockpiles are worthless. Lots of people lose their jobs and others lose their pensions.

Clone currency and dump it around. It's a perfect copy so nobody can tell a duplicate. Physical money becomes worthless.

If the rich and powerful start losing everything, war isn't too far behind. If you repeat the same tactics in foreign countries, war is inevitable.

• As noted elsewhere banknotes usually have serial numbers... duplicating it on a global scale would likely push for banks to retire paper cash and replace it with electronic payment systems that would crash along the gold depreciation. So you might want to first devalue cash then crash the economy. – beppe9000 Sep 18 '19 at 22:31

# No

Over a year, this generates 100,000 people.

This will multiply your power by a factor of roughly 100,000x over the course of a year.

There are many, many people in the world 100,000x more powerful than a random person (most billionaires, for example), and none of them can reliably kill all human life on Earth.

I mean, you could get lucky, but for the most part you'll just cause a fair amount of damage.

Unless you gave this person extraordinary abilities (like, the ability to recursively generate portals), this person isn't significantly more "powerful" or "capable" than a random person on the street, as described in the question.

## The Pen Is Mightier Than The Bomb

Immediate violence is not necessarily the only route we can take. If we fill the car with money and digital devices filled with books on all sorts of subjects or have the person himself learn many subjects in science and biology before duplicating himself, we will be capable of duplicating 'knowledgeable' people. Perhaps this won't make any geniuses, but that concentration of knowledge can be a deadly asset.

Within a few days he could potentially set up a laboratory for biological weapons, or to research nuclear weapons. His efforts would be exponentially effective (or ineffective, if he's not well-versed on the subject). He would have infinite test subjects and funds to work with, in developing his weapons. It would only be a matter of time before he made enough weapons to give him results to end the world.

Another more humorous approach is to load the car with checques, rather than money. He could read up on books on politics and economics beforehand. Using his massive amount of wealth, and his knowledge of economics/politics he could collapse the economies of multiple countries and cause World Wars.

As they say, give a man a gun and he can rob a bank, give a man a bank and he can rob the world.

• Infinite money is worthless money. You just imploded the economy. I don't know if that counts because it's not nuclear, yet. – Henning M. Sep 19 '19 at 20:01
• It's just to trigger the nuclear stuff. Imploding the economy sets the world into chaos, and chaos means war. – Enthus3d Sep 19 '19 at 20:11
• It doesn't guarantee nuclear winter, but it means society itself will be in chaos with the political and economical systems completely disrupted. – Enthus3d Sep 19 '19 at 20:12

## Attack drones carrying nukes and long-range fuel tanks

I also don't see any restrictions about "wishing for infinite wishes" i.e. creating more duplicate portals, so I'm going to go with Von Neumann probe attack drones, carrying nukes and a duplicator portal kit (just to speed things up). Although as it turns out, even if duplicating the portal isn't allowed, I don't think being limited to a single replicator will end up mattering that much.

You haven't provided any capacity limitations other than "about 5 per minute" and the requirement that any duplicates have been continuous operating exactly like the original (e.g. battery / food consumption), so the main restrictions for any solution are going to be either speed in replication/distribution, or sufficient firepower to maintain an advancing front at a slower pace. I'm going with some of both, and allowing for decentralized production.

I'm going to just stick with back-of-the-envelope estimates on the math, but this actually looks a lot easier than I anticipated.

## Delivery System Design - Range and Coordination

Let's start with a standard Reaper drone, a existing, real-world, combat-proven design. We'll need to modify it slightly so the wings (and maybe the tail and landing gear) fold back to fit through the car-sized entryway, but otherwise this looks like a pretty good starting point:

• Max speed 300 mph (480 km/h)
• Max payload 3,800 lb (1700 kg)
• Flight time 23-42 hours (depending on loadout)
• Range 1150 mi (1850 km)
• Altitude 50k ft (15 km)

These drones will have plenty of speed to clear the production area, especially if you put the original portal in the back of a cargo plane already in the air and let them come blasting through at full speed and out the back of the plane, where they untuck their wings and disperse. This is only a boost to the 1st generation, but it gives you a needed jumpstart before anyone can respond and try to down your tide of doom. If in-flight deployment from a 'fixed' point in the bay of the plane turns out to be forbidden by the OP, it's not a deal-breaker though.

2nd modification is going to be the power/fuel supply - we need to get a clone of the original to the other side of the planet to achieve full annihilation. It either needs an in-flight recharging system, or enough power to go the full distance on it's own. Let's check our initial range for an example loadout with 2 external fuel tanks and 'only' 1000 pounds of munitions - 42 hours of operation. At 300 mph, that's a 12,600 mile max range; we'll talk about the operating limitations in a minute, but our drone can already fly that far out of the box.

Getting halfway around the globe requires a range of 1/2 the Earth's circumference - 24,900 / 2 = 12,450 miles. Ok, we're already there! But, we need some allowances for replication time, opposing winds, lost units from aerial defense, etc... But we don't have to actually spread our swarm all the way to the antipode of Ground Zero; we just need to cover the land masses, and honestly after getting a majority of those completely coated with nukes, the fallout and weather are going to take care of the rest in a few months.

## Location, location, location

Let's start our doomsday plan off the coast of central Africa, say over São Tomé and Príncipe, because all super-villain plans to destroy the world should start on a volcanic island. We'll save the islands of the Pacific for straggler drones to clean up (or just let them perish from fallout/starvation after a few months). The farthest land radially from there, from eyeballing a globe, is only about 2/3 of the way around (either New Zealand, Japan, or Alaska), so 12,450 * 2/3 = 8,300 miles. Totally doable for the Mark 0 (and any derivates) on a single tank, so no refueling to deal with! Perfect, because carrying and transferring fuel for future generations was going to be a huge hassle.

Okay, so our drones can reach the far ends of every continent - how do we control them? The original range limit of 1150 miles is based on communicating with a single, central control location; but our drones are going to be autonomous. They just need to divide up the work. This isn't terribly complicated - the Mark 0 could have a set of pre-planned routes, and each copy would get assigned one while coming through the portal (with plenty of redundancy for some getting shot down). Or just let them play zone coverage and collaborate with the nearest drones about who's going left or right. They'd need a securely encrypted, on board, distributed communication network to coordinate with, but a wi-fi mesh isn't exactly new technology.

## Weapon Choice

So, while other villains might introduce a super-plague, or accelerate global warming with a moon laser, our plan is good ol'-fashioned nukes. Rather than try to re-invent the wheel, Mark just needs to steal a single nuke and crack its command codes. And probably replace them with his own well-tested system, since every single copy will have the exact same vulnerabilities.

We could go for the biggest one we could find... The Tsar Bomba was ridiculously large at around 50 megatons, but is not a production weapon, so let's try the largest currently in the US arsenal, the B83 with a yield of 1.2 megatons. Yield is almost always compared to the Hiroshima yield (1bout 15 kilotons), so around 80 of those. Sadly, this firepower comes with a weight of 2400 lb (1100 kilos), which is double our weight budget after loading up on fuel tanks.

On the other other of the spectrum is the portable hand-held mini nuke, which weighed only 51 pounds - our drone could hold 20 of those! Sadly it only had a yield of 20 tons, or .02 kilotons, or 0.0002 megatons... ok, the technology has improved, so a similar size would yield a lot more these days, but that's still far too small for total world destruction on a schedule. Let's find some middle ground - I picked the recently-retired W87 warhead at random from a Wikipedia list. A design yield of 300 kilotons, upgrade-able to 475; only 1/3 to 1/4 of the B83's yield, but at a weight somewhere between 440-600 lbs (200-270 kg) we can carry 2 of them. There's probably some similar design with a comparable yield and lower weight, and we could strip off some safety shielding at the last minute to save weight, so we could potentially carry 3 or even 4 with a yield in that range.

## Attack Plan basics - no re-replication

Ok, we've got autonomous nuke-carry drones streaming out of a portal - where do we send them?

Our lair on São Tomé and Príncipe has not just the advantage of being centrally located geographically, but is also about as far as possible from most of the nuclear countries. This maximizes how many drones will be in the air before the initial strikes and counter-defense. You'd obviously want a lot of firepower in play before starting, but let's assume you're going to going to start things off in the Middle East because of the history of nuclear tension in the area - might as well try to trigger some MAD attacks and get some help from the existing nuke arsenals around the world.

I'm not sure what air defense most of Africa has, but it's a fair bet that a constant stream of drones would be world news within a few hours. Obviously you'd plan ahead to map out ideal routes, but even with high altitude flight some airports are going to see you and demand to know what's going on over their airspace. No one's going to start shooting immediately, so let's pick Egypt as the first point of attack for our expanding fleet where interception begins.

The middle of Egypt is 2400 mi (3880 km) away, or 8 hours of flight time. If we've been pumping out 5 drones per minute the entire time, our fleet consists of (5 * 60 * 8) 2400 drones, either spread semi-evenly across all of Africa, or more likely weighted toward the north to deal with the impending resistance from nuclear countries. With 4 nukes each, that's 9600 nukes to start neutralizing defense threats with across the entire continent, plus an additional 2400 kamikaze kinetic drone attacks after bomb/missile deployment that can continue much farther afield to start softening up future targets.

Without even looking for maps of international defense installations (I'm sure my search patterns are already raising some flags), I'm going to assume that's enough to do some serious damage and erase response capability over a several hour radius. If our drones have some simple air-to-air measures as well, that's probably enough to put up a pretty impenetrable barrier; even without self-defense, they could just fly to intercept and scatter their payload on a short fuse for a pretty formidable blast wall.

So, just keep pumping drones farther and farther afield until we've coated the entire Earth to a sufficient degree. Starting with Africa (aside from a small clear zone around the base) - 20% of Earth's land area, ~12 million square miles, divided among our 9600 nukes, is 1 city-killer every 1250 square miles (or a square ~35 miles per side) in the first wave of attacks. Not exactly carpet-bombing, but given that human population is mostly gathered in cities we wouldn't actually spread the attack evenly across a grid. That's pretty thorough coverage for the first wave.

At that point, drones emerging from our base still have 34 hours of flight time, and can still reach the far edges of our target areas. We could let a dozen or so of the first wave head over the Antarctic or South America to deal with the stray islands in the Pacific before later drones could no longer reach.

## Attack Plan 2 - infinite wishes

Now, we've done this all with a single portal - what about thinking with portals? The basic plan seems pretty formidable already, but what if we could expand production?

We don't know anything about the portal itself except that it needs to be fixed to something to start operating, and can't be moved again once it starts operation. I think the intent of that restriction was probably to prevent just moving it all over spraying materiel, so I think replicating the 2nd prototype seems reasonable. It's definitely the first thing any self-respecting mad scientist would try after inventing it. It also blows up expansion, if you'll forgive the term, incredibly fast and leads to overwhelming forces that tend to ruin a story if left unchecked, which is why Von Neumann probes are a) not written about that often, b) are a terrifying idea that are generally expected to result in the destruction of everything they touch if some lunatic ever actually builds one, and c) would have rate/generational limiters built in if there was really a reason to use them. But, we're here to destroy the world, so don't worry about any of that.

Let's make it a square metal frame that's relatively thin, so the assembled version can a) be carried and deployed on the back of the drone, b) contain its own unobtainium power supply, and c) be angled to fit diagonally through its clone's opening. Let's also assume it takes a negligible amount of time to set up and switch on, and starts working immediately. Adding a small delay (5-10 minutes) slows things down a bit, but doesn't really affect the math long term. So hey, to keep things simple let's make The Device air-droppable, so the drone can slow down, drop it low and slow over an open field, and then do a barrel roll and dive into it just after it comes to rest and powers on.

Obviously you need to spread your base of operations to a) provide redundancy when the counterattacks start, and b) improve your coverage and rate of production. This may be Earth's last day, but you still don't want it to take all day.

Let's skip the advanced calculus of exponential growth rates, acceleration/deceleration times, etc, and just look at replication as batches of drones, with a new wave every 30 minutes flight time. That gives you a production ring every 150 miles (240 km). Each portal running at 5 copies/minute will make 5 * 30 = 150 new copies every generation. Every single drone then continues to disappear into its newly-deployed portal every 30 minutes, until after a set number of generations we decide there's enough to carry out the actual attack and stop making new portals. Turns out, that's probably only 3 generations, after which we can quit worrying about enough drones and start worrying seriously about air traffic control.

• Gen 0, t+00:00 - 1 drone; 1 portal
• Gen 1, t+00:30 - 150 drones; 150 portals
• Gen 2, t+01:00 - 22,500 drones; 22,500 portals
• Gen 3, t+01:30 - 3,375,000 drones; 3,375,000 portals (end portal reproduction)
• Gen 4, t+02:00 - 506,250,000 drones (every 30 minutes)

So only 2 hours in, we're producing 500 million drones, with 4 huge nukes each, every 30 minutes, somewhere within an expanding cloud with a radius of only 600 miles. Or in other words, 2 billion nukes (1 for every 3.85 people on earth), loaded in long-range drones, every 30 minutes. In the 8 hours before first strike in our initial scenario, there will now be something like (500M + 6*2*500M) 6.5 billion drones (26 billion nukes) dimming the sun over the entirety of Africa and much of the south Atlantic.

Forget about targeting just the continents at this point. Earth's total surface area is only 196.9M square miles, so we're at 1 nuke for every 0.0076 square miles, or a square ~460 feet (140 m) per side. Better 20 Hiroshima explosions per city block, with uniform coverage worldwide.

...I'm not even sure you need an attack plan at this point, international nuclear defense capabilities just can't deal with those sorts of numbers. Just assign each drone a coordinate, and sit back to watch the show.

• I'm so sorry, I wish you'd asked in a comment whether you could duplicate the portals before you went through all this work writing up a response. You really can't duplicate the portals, for subtle reasons, so... yeah, sorry. – Gilad M Sep 18 '19 at 23:10
• Okay, now after having read the full response, I see that you wrote a version that has no replication and is actually very potent. The main issue I can see with this is how to get the drones and weapons in the first place. This guy has military training, sure, but there's no easy way for him to obtain drones and missiles worth millions. He can't duplicate money to buy them either, since that would require more than one duplicator, which, yeah, again, won't work. Sorry I'm not going into details, but trust me, last time I tried, it was so confusing that the comments became a mess. – Gilad M Sep 18 '19 at 23:20

Plan A Fly a very small plane through the "gateway," the plane can be angled slightly to make sure it fits correctly. Approximately every 10 seconds a new plane will materialize from the gateway. Every 10 seconds a 9/11-like terrorist attack happens.

Plan B (Unrealistic Version) Attach an exo-suit to a fresh corpse that died from a specifically modified bacteria that is designed to survive long after host-death and slow down host decomposition. The exo-suit has an AI and can connect to others of its type to learn and send commands. This would create a web-like connection between all nearby suits leading back to a computer conveniently placed near the gateway. Duplicate the corpse after activating the exo-suit. Essentially this would create a zombie and after duplicating it, we now have a whole apocalypse.

• Hi Red, welcome to the site! The main issue with this is I don't see an average person getting hold of a small plane or an AI exosuit. The guy needs to actually own this stuff before he duplicates it. And even if he did, crashing a plane that small into a building would only hurt a few hundred people at most. It's dramatic, but the scale is too small. – Gilad M Sep 19 '19 at 8:54
• @GiladM Since when does the "average" guy want to end humanity? What average guy has a duplicator? This guy is anything but average. I'm sure he can steal a small outdated crop-duster or plan ahead to get something smaller. Now you also said it would be ineffective; what if 6 planes hit a tower in under a minute from first to last? One minute later 6 hit the other, and these are small, so they don't need to aim high, they can hit the base if the pilot wanted to. – Red Sep 26 '19 at 1:27