Professor Y is trapped in a virtual reality. The VR is running on accelerated time to the point where he can live out millions of lifetimes in a real-life day, basically giving him immortality within the VR world. He also has godlike powers within the world, as he is a sysadmin. His goal is to escape. He has two options:

  1. Use his sysadmin powers to terminate the world. However, because of the nature of the accident that trapped him, he is 99.9% certain this will kill him and anyone else who happens to also be trapped (he doesn't know how many others there are).
  2. Wait for a very specific set of circumstances to be true, which will allow him to end the world safely and get everyone free.

Y would obviously prefer #2. However, the circumstances required are exceptionally precise and rare; it requires a massive amount of random events to be just so. There is no risk of him missing the opportunity if it does pass, but if something doesn't work out, he has to wait several thousand virtual years for the system to do its regular reboot so he can try again. In fact, probably 90% or more of the iterations won't be anywhere close to having the necessary circumstances. Think of it like repeating human history until you get a world where the first man on the moon is named Jeff Bulliord and has three kids (one of them adopted), plus several dozen other such statements that must also be true.

Y is aware of what the necessary circumstances are, and he can use his godly powers to try and push events in the needed directions, but he only has an average person's sense of the butterfly effect. Only once things get very close is it reasonable to expect his actions to to more good than harm. Otherwise, he's going to spend several million lifetimes sitting around waiting for the next iteration of the world to begin because this one didn't work out.

Obviously, Professor Y isn't going to remember a lot of this. He's only human, and the system isn't going to help him remember things. I'm interested in how long it's going to take for him to forget the most important things, such as:

  • his name/who he is
  • his goal, or the reason behind his goal
  • the fact that he's a sysadmin in a rebooting virtual reality, and not an actual god in a cyclic world

Additional notes prompted by comments:

  • Professor Y might have some godly powers, but if were to just throw them around on a whim he'd almost certainly mess up what he's waiting for (and possibly turn the world against him). He has to be more subtle.
  • Professor Y's persona in the world is ageless, though he can make it appear to age as necessary so he doesn't attract attention. He begins each world iteration just as he finished the previous one.
  • The system reboots at a predictable interval. Once rebooted, the starting state is exactly the same every time, but with a different randomization sequence; compared to the length of an iteration, it doesn't take long at all for the "new timeline" to become incomparably different than the previous one. Professor Y can't do anything about this.

closed as off-topic by Mołot, Azuaron, Green, Murphy, Frostfyre Dec 13 '16 at 18:58

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  • $\begingroup$ Absent brain damage/deterioration (e.g. Alzheimer's) how does anyone forget who they are? Of course that 'who' is something that evolves through time & experience, so it probably will change, as will the things that are important. As for names, they are just labels applied by other people in different contexts. For example, what I'm called by my professional colleagues is not what my friends call me, and that's different from what I was called in the military... $\endgroup$ – jamesqf Dec 11 '16 at 0:07
  • $\begingroup$ Does Professor Y have to relive a full-length childhood for each iteration, or does he (or can he choose) to pop in at a specific chosen age (e.g. 18 or 21) and/or choose to create a new iteration as a branch of a previously lived life at a specific chosen point (e.g. the day that Y met an aspiring pilot named Jeff Bulliord, but before Y took Jeff to the wrong singles bar that caused him to swear off of love forever, rather than have the 2 biological children that Y expected him to)? $\endgroup$ – Robert Columbia Dec 11 '16 at 1:48
  • $\begingroup$ @RobertColumbia Added notes based on your comment. $\endgroup$ – Sir Teatei Moonlight Dec 11 '16 at 3:04
  • $\begingroup$ How analogous is this VR to real life? The short answer is "it depends on how the VR mimics the brain". If there is dementia, or if memories degrade at normal rates, for instance, the answer will be effected. $\endgroup$ – Zxyrra Dec 11 '16 at 6:00

Over 340 years worth of memories with lots of caveats

The first caveat is that this is stored memories. Things not worth getting stored would be forgotten or more important things would overwrite them and memories can morph over time increasing or more likely decreasing the amount of space they are taking.

Scientific American had an article on the brain and its capacity. It estimates the brain could hold as much as 2.5 petabytes of information or 3 million hours of recorded TV (which higher grade video formats would be even less). Unfortunately there is no direct way to know how much memory our brains dedicate to a memory and it likely also varies by person.

In order to make this answerable lets add a second caveat. Let say Professor Y's brain cannot exceed the quality of recorded TV or in other words a memory at that level would be a photographic memory. This allows the 3 million hours to become a lower bound number of 342 years. If Professor Y stores some really low res memories it will greatly exceed that.

Otherwise, he's going to spend several million lifetimes sitting around waiting for the next iteration of the world to begin because this one didn't work out.

Now lets say a single life time was 70 years and I will take several million lifetimes as being two million lifetimes. that give 140 million years. At those number Professor Y would only be able to remember 0.000244% of a single cycle. At such low numbers Professor Y is not going to even remember the highlights. The only way Professor Y is going to remember the important items that you listed will be to use brain exercises to intentionally remember it.

Millions of lifetimes in a real-life day

I recommend cutting this figure back dramatically along with the length of a cycle. Civilization has only been around for a mere 200,000 years. With millions of lifetimes in a real-life day (140 million years), that is 7,000 times bigger.

Brain has limited speed for storing data

To borrow numbers from brain capacity the brain would need 833 MBs of space per hour of TV. If the Professor has an excellent memory his brain would need to be able to write to memory at 237 KB/s. However the VR is running millions of lifetimes in a real-life day or in other words 5.8 million times faster. The brain simply cannot store data at 1.3 TB/s. So I hope the VR has good exception handling since the brain is going to be throwing lots of file IO exceptions.

This is very good news for Professor Y attempting to remember important items. Since his brain cannot keep up with the incoming data almost all of it is going to be lost before the brain can store it. Thus the brain will be kind of acting like it is in read only mode.

Brain as a processor

The brain also needs to process and respond to the input given to it from the VR. According to this research paper humans auditory reaction time is 140-160 msec and visual reaction is 180-200 msec. Lets say the brain is directly hooked into the VR and given drugs that bypass most of the reaction time and get it down to 1 msec. That is still too slow for the VR. By the time the brain has processed an event and responded 5.8 million msec have passed in the VR or 96 minutes. Someone in the VR asks the Professor Y what his name is, they would have to wait 1.5 hours for him to respond.

Brain needs calories for power

Let say all the brain speeds got hand waved through a magic chip that causes the brain to go into awesome overdrive mode while in a VR setting. Brain needs fuel to operate, and it is quite an energy hog. According to share care the brain uses about 20% of your total calories, or 400 calories of a 2,000 caloric diet. So if the brain's speed is upped by a thousand fold, guess what it is going to need? A thousand times more fuel. In this case it likely will need to be upped by a factor of a million, but lets go easy and say 100,000 fold increase. The brain would end up burning through 40 million calories of food in one day. Butter is a good source of calories coming in at 717 calories per 100 grams. In other words Professor Y's brain would need to burn 5,500 Kg (6 tons) of butter a day to keep up with the VR.



The "forgetting" experience someone experiences being trapped in a continuously resetting virtual reality is probably less akin to amnesia, and rather more like depersonalization. In basic terms, it is the loss of the idea that your ideas and feelings belong to yourself.

Depersonalization is used by states to encourage obedience in prisons etc. The main tactic is frequent, arbitrary changes of environment and cellmates. An inmate condemned to life in Gulag A becomes resigned to it, spends a week working out who's who, then finds they're being put on a bus to Gulag B.

Hopefully none of us will find out what this is like, but you can read about it from people who do:

Nelson Mandela: Long Walk to Freedom (1995), Aleksandr Solzhenitsyn: The First Circle (1968) or Denise Chong: Egg on Mao (2009).

I expect being trapped in a virtual reality would be the same. It sounds like Professor Y has no power over himself whatsoever. Living for thousands of years while generations shuffle past around him, living through reboots and resets.

Psychologically, being an inmate (politcal or otherwise) in a vast prison system is the closest real world scenario. Fortunately, while the psychological field's interest in this is lacking (although that's changing), there are first-hand accounts.

How long would it take?

Psychologically-speaking, Professor Y is undeniably in a bad situation. In accounts from political prisons, people can forget their motivations and alliances on the first night. Apparently, just the expectation that a relocation will occur already packs quite a punch. The best example of this in Western (US, British, European) detainment facilities abroad, where inmates know that a short trip across the border can change all the rules (you'll find this stated in survivor accounts, I can't remember the reference).

The main drivers of depersonalization are arbitrary changes in the environment and its occupants. How long Professor Y lasts would depend on how frequent the resets are. Then again, if the scope of the "randomization" is wide, he might not make it through the first one.


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