First question here so don't hesitate to pinpoint me if need be.

I was wondering: If there was a very convincing, advanced simulation of the real world or a fantasy world how would one go about crashing it?

The only examples I have are kind of weak but here goes: If you were trapped in a "sword art online" type game about the size and complexity of World of Warcraft, could you manage to crash it by exploiting a glitch like for example duplicating an item infinitely, by using a plate to traverse space (as in Skyrim for example)?


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    $\begingroup$ Welcome to WorldBuilding Demiurgo! You might be interested in some of the questions already on the site, such as If our universe was a simulation, what could a bug look like? and Hacking the universe. If you have a moment please take the tour and visit the help center to learn more about the site. Have fun! $\endgroup$ – Sec SE - clear Monica's name Sep 2 '17 at 9:47
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    $\begingroup$ Premise is where you give us basic information about the world you are building, so that we know what it is about, what rules govern it, and other such pertinent information that helps us to understand the problem. The Problem is quite simply that which prevents you from continuing authoring your world. You might need some credible plot element; a reality check to see if your idea works; some calculation. The Query then is the question that — if answered solves the problem. Try this setup and edit your question accordingly, and we will be glad to answer your question. $\endgroup$ – MichaelK Sep 2 '17 at 10:40
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    $\begingroup$ Adding to @Secespitus' comment, I do want to point out that both of the questions linked were posted very early in the site's history, basically while we were still trying to figure out what was needed in order for a question to be answerable, and at least the latter was the subject of a discussion about whether it was indeed too broad, even at the time. Please note that questions about magic specifically require you to specify the magic system in use; that's because otherwise, they become "anything goes", which doesn't work well for us. This question feels similar in spirit, if not wording. $\endgroup$ – a CVn Sep 2 '17 at 10:44
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    $\begingroup$ @MichaelK Pro tip: Type your entire comment as you intend to post it, even if it grows too long, and then split it up. Then you can post the parts in quick succession, reducing the risk of someone else posting a comment in between the parts of yours. $\endgroup$ – a CVn Sep 2 '17 at 10:45
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    $\begingroup$ Run it under Windows? $\endgroup$ – jamesqf Sep 2 '17 at 17:11

Read Anton Golov's answer to if our universe was a simulation what could a bug look like?

To crash it you need a bug in the simulation to exploit; and very few such bugs are actually going to crash a simulation; most will appear to be some sort of anomalous or inconsistent physics.

For example, in simulating movement of objects, I once had a bug in which my simulation let one type of object pass right through other objects, instead of colliding with them.

A simulation could fail to translate physical position under movement: To us that would look like a moving object suddenly jumped in space or just disappeared. Or perhaps the bug looked up the wrong physical characteristics, and an object (as small as an atom, big as a world) suddenly turned to solid uranium or hydrogen.

Most bugs do not crash programs; they just make the program do something unexpected. Inside the simulation, this would look like a new law of physics, or just something we never can explain. (Think of mysteries of the universe we have now, like Dark Matter, Dark Energy, the lack of monopoles, and several other anomalies in physics). It would be something that does not seem to add up or comply with the physical laws we have discovered about how the world and universe and all its systems work (including biological, chemical, physics and particle physics).

To Crash It, you'd need a runaway bug; and from inside the system this would be either unnoticeable (like time comes to a stop) or some kind of exponentially growing "infection" of the universe that destroys everything (e.g. a black hole that is unexplainably growing fast and will swallow everything.

The manifestation of a crash of a simulation is always a halt of the simulation; the program stops running. Now the computer I am running on may be processing instructions at full tilt; but if I am in an infinite loop the simulation isn't going anywhere: It is halted.

Most crashes are a result of bugs that accidentally over-consume resources, like computer memory or storage space, so the machine doing the computations for the simulation (which obviously is not IN the simulation) does not have the resources to continue. Or, giving such a machine orders it cannot complete; like to decide on a course of action using a variable that has accidentally been left 'undefined' in the code.

You might not ever see it.

IRL, many simulations take very long for us to run (Last year I read Military researchers required about a week of calendar time to accurately simulate air flow for thirty seconds worth of flight for a new kind of multi-rotor drone supply platform).

Because of that, many such simulations take check-points, where they store a 'snapshot' of the entire system every so often (like every 15 minutes), both to help them track down bugs and crashes, and if they are confident the problem did not affect the simulation up to some previous checkpoint, they will restart the simulation from that checkpoint.

From inside the simulation, we would not ever see the crash:

Suppose a simulation crash in our 2015 leads to the destruction of the universe. Our simulation programmers, trace this back to a bug that first manifested itself in our 1987: When Fleischmann and Pons first recorded cold fusion. But unlike our history, that turned out to be real, due to a bug in the simulation's treatment of interactions between palladium and deuterium. Once this interaction starts producing free energy, a runaway reaction causes a black hole that consumes the universe. Bummer.

The simulation programmers investigate this, and being clever, they figure out a way that Fleischmann and Pons might have seen what they saw, but with their results being due to some sort of intermittent equipment problem (and their experiments were intermittently 'successful' and not) localized to their lab.

They have a checkpoint from 1972, with a slight modification they can introduce this equipment flaw, and also correct the interaction bug. They restore the universe to that state: Things work out ever so slightly differently. Palladium and Deuterium interactions produce zero free energy; the bug is corrected. The equipment flaw trick Fleischmann and Pons, but their experiments cannot be replicated and they are discredited. Nothing at all happens in our 2015, and the simulation continues: But the simulation programmers have saved 13.7 billion of our years in simulation time, and perhaps that makes a difference to them.


You are speaking about a "glitch", which is a specific bug in programming allowing you to do things you shouldn't be able to do.

If this can crash the game it is dependent on the specifics of the glitch itself. It's not something that can be seen "a priori", you play and you (possibly) use bugs and exploit them in "creative" ways.

This is completely different from logic inconsistencies (eventually) present in the simulation (e.g.: magic system allowing you to create arbitrary amount of matter), which you may be able to exploit or not.

Example: with a magic system like the one above you could create a mass greater than that of the whole planet some kilometer over your head and literally "crash" the game under its weight; otherwise You can spawn continuously rabbits till the game crashes trying to keep track of them all.

Other types of inconsistency would leas to different paradoxes with which the system may or may not be able to cope (a system might overflow simply failing to spawn more rabbits, instead than crashing).


Usually games only crash on the client side, meaning that the game crashes on the console/computer of an individual player, which would only affect that player. An MMO would need to have a serious design flaw in order to crash the entire server for everyone. Usually such a bug would involve either database corruption or a runaway process using up all of the server's RAM or CPU power.

One possible idea would be to build a machine in the game so complex that the server would become overwhelmed trying to process all of the physics calculations for it. If the server has to devote all of its resources to the calculations, players will start getting dropped as the server becomes too busy to handle them. This would obviously require the physics to be calculated server-side


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