Talk:Quantum immortality

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• Archive 1
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Contents 1 how to test it, and save everybody 2 Fork Bot in RoShamBo programming competition 3 Assumption that consciousness is able to transcend universes 4 Removed info 5 Study in sexism 6 Some ideas 7 Quantum Suicide 8 Immortality and the issue of morality,quantum +cyclic 9 What about the Biblical long lived people? Like Methuselah 10 which survivor-states are more probable? 11 Can there be only 2 different branches? 12 The immortal amoeba 13 Nuclear weapon example 14 Mathematics of QI 15 Need another example 16 David Lewis argument flawed? 17 Does Quantum Immortality suggest this? 18 resolution

[edit] how to test it, and save everybody

looking at 'test it and get rich' gave me an idea, for two people to see if it works all they have to do is have a scenario where they either both live or both die (like putting a very large gun to their skull and stand head to head, so that if the bullet leves the gun it will pass through both of their brainstems) after pulling the trigger a few 1000s times they whould be able to know for sure. and be able to prove it to the other persons. now change those two to 20 people and the gun to some bigger like a bomb.... now if there was a society where everyone has a implant at birth that can tell if they are alive or not. Now if that implant is hook up to a doom day bomb that will blow up the world killing every one if evening one person dies… from their point of view the ONLY worlds their would end up is were everyone lived, ego making an Immortality society. Joeyjojo 04:28, 12 June 2006 (UTC)

<Sigh>, yes. but we don't want to give the whole story away. Otherwise we'll end up with people aiming very large asteroids at the Earth in the name of science trouble. Best to test it out with the 20 people before involving everybody. After all it might not work. -- Derek Ross | Talk 05:59, 12 June 2006 (UTC)

But if you just used 20 people, wouldn't that mean that while those 20 people lived through the event, the rest of the world would live through the one that didn't?

Not if you do it right. Twenty people in a sealed room with the cyanide linked to the lottery results. Everyone else safely outside. Do it that way and you'll convince twenty people. Of course the rest of the world will arrest you as a mass murderer. Best of luck with the "I was only doing a scientific experiment" defence, <grin>. -- Derek Ross | Talk 01:52, 19 June 2006 (UTC)

If applied to the society as whole, we come to the anthropic principle ;-)--Nixer 21:43, 18 June 2006 (UTC)

Well, well. Whaddaya know! -- Derek Ross | Talk 01:52, 19 June 2006 (UTC)

Okay I have work on it a bit...

How to become a Immortality society a few easily steps*.

With the natural system of Quantum immortality Mankind will fragment till we all end all in our ‘survived world’ 1000s of years from now, each human being with be alone in this world, at the edge of death but never actual dieing. such a fate would be wost then death

However the is a way around it….

start with the twenty people (and yourself or odds are you end up in the "mass murderer world'). Tried to committed suicide and survive for more than is numerary possible, you be able to convinced those twenty people that quantum immortalityis real just along as the form of suicide will kill you all at once.

The best way to do this would be a implant that would kill ever one at the same time if one of the group die. This can be done with to day’s tech. As the only world in which any of your group lived is the world where all of them lived, they would all end up the same ‘survived world’ together as one. ( please overlook the socialism overtones)

To any outsider who is watching and had the luck to end up in the ‘survived world’ rather then the ‘mass suicide world‘. to them the group would seem to be immortal. (but only in a small number of world where they all survived)

This gang of immortal being chould go then around the planet picking up others any one who want to live forever with company and grow in number till every human being is linked up with this ‘all of one, one for all’ system,

With the earth the linked to the same ‘survived world’, the world will soon become a very different place. They will be no more death, however overpopulation will become a problem, which will probably be over come will scirty informent of conreaseted

Worse still the old will no longer die (from this immortal society point of view) and still get old. And we soon come under the burden of looking after millions people 100s of years old and those who have been crippled by illness and injuryers that would of normally ’kill’ them. What will most likely happing is that the old and sickly will live in fear that some one would come along and ‘unplug’ them from the system, and then go off to they own personal ‘survived world’ (which would probably a very bad places as the whole of the human race would be wipe out as soon as some one dies)

But it’s not all bad, with today brains and tomorrow’s tech we should be able to live into a till a technologically signanltiy saves us and we can all live forever in freedom and safety………..maybe

(It would make a good setting for a sic-fi story (if any one who uses it be sure to credit me ;) )

• I do not take responsibility for anyone trying this

Joeyjojo 06:22, 21 June 2006 (UTC)

You misunderstand the principle. It's far likelier that mankind would not agree to have implants installed, thus preventing the scenario from happening. Even if you were able to get 20 people to agree to be hooked up to this killing machine, it's far more likelier that the machine fails and leaves one person alive (all 20 becoming sole survivors in their respective realities, thus still ending up alone). If you somehow were able to make a device with a 100% success rate, then you would die with 100% certainty, living on in the realities where you never decided to use the device in the first place. Also, it is impossible to live forever alone in this world on the edge of dying, because you will eventually die of old age. It's far more likelier that mankind invents some kind of longevity technology that will allow your consciusness to live forever (maybe by lengthening the natural lifespan, or by uploading minds into machines), but you'll still end up dying in all the universes where mankind doesn't develop this technology. --85.157.224.88 20:50, 27 June 2006 (UTC)

Okay maybe I went a little overbroad on how we can all live together. But the point I was trying to make at the start is that under some artificial conditions you should be able to have it so you can test it with several people at once (and so proving it to themselves, and those who are in their universe that their lived in). And no all the machine whould have to do is kill all of you with 100% certainty half of the time and live the other half. say an cion filpe, if you set it to kill you on heads than it should come up on tails every time.Joeyjojo 02:43, 7 August 2006 (UTC)

I wouldn't worry about it. There are probably a few universes in which mankind will invent a way of resurrecting everyone who has ever lived anyway. TharkunColl 14:51, 10 September 2006 (UTC)

Sorry to break it to you, but most of what people have said about making everybody immortal just plain doesn't work. Quantum immortality only applies to you. No one else is affected. Constantly attempting mass suicide does not prevent anyone else from dying from any other means, even if the suicide fails every time. In other words, the fact that everybody is attempting suicide does not save everybody from your point of view. Only you are guaranteed to survive.

Another fact you have to consider is that your survival can and in some cases will be insanely miraculous. Even if quantum immortality works, that doesn't guarantee that a bomb that would kill you and everyone else on Earth if it exploded will not explode. Due to the nature of quantum immortality, once in a while the bomb will explode, and somehow you will be saved by a seemingly impossible fluke of probability. And I'm not just talking about suddenly being beamed up by a flying saucer or teleported to another planet through a wormhole. It is not unrealistic, once we have assumed that quantum immortality works, for the bomb to blow the rest of your body to pieces while your brain continues to exist, floating unscathed within a nuclear inferno because you have to survive. Similarly, as the Heat Death of the Universe approaches, quantum mechanics will supply your consciousness (however it exists at that point; it will probably not be a biological brain) with energy in just the right place and time to keep it going. It would be possible for every part of you not necessary to retain your perception to eventually be destroyed due to the laws of thermodynamics, but the necessary parts will go on surviving for eternity in a dark, cold, and very empty universe. - green_meklar 01:55, 12 October 2006 (UTC)

[edit] Fork Bot in RoShamBo programming competition

Here's something that could perhaps be added to the article. In "The First International RoShamBo Programming Competition", there was an "Unofficial Super-Modified Class" for programs that cheat in one way or another. One of the contestants was the Fork Bot, which split the process into three, made a different move in each, and destroyed the ones in which it did not win. Reference: Darse Billings, "The First International RoShamBo Programming Competition Results (Part 2)", http://www.cs.ualberta.ca/~darse/rsb-results2.html, last updated October 4 1999, viewed July 14 2006. 213.216.199.2 04:40, 14 July 2006 (UTC)

[edit] Assumption that consciousness is able to transcend universes

Isn't that another huge assumption that has to be made for quantum immortality to be valid? That consciousness exists outside of the bounds of universes? For this to work, it requires the assumption that the same person's mind in separate parallel universes are not different entities, but just one entity, or somehow connected. If the MWI is right, whenever a universe splits, doesn't each universe become a separate dissociated entity? Why should the conscious mind be any exception to that? To each copy of someone's mind in each universe, it'd be as if none of the other minds existed, as long as it's all bound to one universe. So how can someone's conscious perception jump across these universes? -- myncknm 00:09, 6 August 2006 (UTC)

No, this assumption isn't necessary and isn't a part of the concept discussed in this article as far as I can see. Each universe's copy can be wholly separate from each other, all that's needed is for them to be sufficiently similar that they're still effectively the same thing. Sort of like if you make a whole bunch of photocopies of a page and then most (but not all) of them are destroyed in various accidents - you can still consider the page to have "survived" in the form of the remaining copies. Bryan 00:20, 6 August 2006 (UTC)

Well yes. The article says that a result of QI is that a conscious being can never experience death, since that being will always be alive in another universe. In the photocopy example, if one copy is destroyed, then yes the original contents of the page will still be preserved, but still that one copy no longer exists. I guess that the point that I'm trying to raise then, is that consciousness isn't necessarily represented by the contents of the page, but each individual photocopy. -- myncknm 00:29, 6 August 2006 (UTC)

I'm not entirely sure what you're proposing "conciousness" to be if not the contents of the page. The position you describe here seems sort of like dualism to me, but if the nonphysical part of consciousness is duplicated along with the physical part when worldlines diverge then I don't see what difference it makes to the end result. QI never said that no copies were ever destroyed, just that there would be some copies left over to carry on. Those leftovers are the ones that never experienced death, by definition. Bryan 00:57, 6 August 2006 (UTC)

Here's an attempt at explanation which may be helpful. Firstly there is no other universe involved so there is no assumption to make. The Many Histories/Many Worlds Interpretation refers to the evolution of our single universe as seen from the perspective of an omniscient godlike being, able to view our universe in its entirety. Being rather less than godlike we can only see those parts of the universe which our limited senses can communicate with. So the mention of "parallel universes" in the article is simply an explanatory device used by the article to try to explain to the layman. The real situation is much more complex: the mathematics shows that not only do the "parallel universes" "split"; they can also "merge" under the right circumstances. This is what makes quantum computing feasible and is also what explains the outcome of the single photon/dual slit interference experiment. In reality MWI/MHI states that there is only one Universe which is much, much more complex than it appears to our senses. What you call "separate universes" are better thought of as parts of a single universe which can only interact in highly restricted ways (ie by "merging").

Now I'll turn to your point that "conscious minds in separate universes are separate and cannot communicate". Basically that's true and the simple answer to your question "So how can someone's conscious perception jump across these universes? is "It can't". The more complex answer, allowing for my explanation in the previous paragraph is "It can't, unless the separate universes are so similar that merger is a possibility". But the fact is that it doesn't matter whether the answer to your question is "It can" or "It can't" because QI doesn't rely on communication between "parallel universes". What it relies on is the communication between one instant and the next; the communication between the "universe" which your consciousness inhabits immediately before the "split" and the "parallel universes" which exist immediately after the "split". Some of those "parallel universes" will hold a "copy" of your consciousness (because you are still alive) and some will not (because you have just died). Naturally you will only be aware of the ones in which you survived; in fact of the single one in which each copy of you finds itself. The fact that the "parallel universes" where you are still alive cannot communicate with each other is neither here nor there. What counts is the continuity from past to future: the fact that all "parallel universes" are able to communicate with the immediately preceding "single universe". I hope that this clears things up for you. -- Derek Ross | Talk 01:47, 6 August 2006 (UTC)

Ah, okay. I think I understand now. Thanks for taking the time to explain it. I thought that QI meant that on death, consciousness would suddenly switch to some other existing copy. -- myncknm 02:06, 6 August 2006 (UTC)

You're welcome. By the way, you might like to read the archive of this page (the link is at the top) for more interesting discussion on the concept. -- Derek Ross | Talk 02:33, 6 August 2006 (UTC)

[edit] Removed info

"A potential criticism of the theory is that the second assumption is not a necessary consequence of the many-worlds interpretation and may require the violation of laws that are still thought to be conserved across all possible realities. The many-worlds interpretation of quantum physics does not necessarily imply that everything is possible, only that all outcomes of quantum processes that are possible will branch off from any given instant in time. Most physical laws of the universe still cannot be broken — for example, the first law of thermodynamics is still considered to be conserved in all probabilities, theoretically preventing a parallel universe in which this law is violated from ever branching off. This has implications that, from the point of view of the physicist, it is possible to reach a particular configuration of reality where the physicist's survival actually becomes impossible, because a survival scenario in that reality would at that point require a violation of a law of the universe that is not considered to be transgressible in any possible reality.

For example, in the nuclear-bomb scenario above, once the physicist has perceived the flash of light from the bomb's detonation, it is difficult to effectively describe a scenario in which the physicist continues living that does not violate basic biological principles. Living cells simply cannot remain alive at the temperatures found at the core of a nuclear reaction under any known subsets of modern science. For quantum immortality to be true, either the bomb would have to misfire (or otherwise not detonate) or an event would have to take place which made use of scientific principles that are not yet proven or discovered. Another example is natural biological death from old age, which may not be escapable in any parallel universe (at least without more advanced technology than is currently known)."

I removed this because:

"According to the theory of Quantum Electrodynamics, there is never a scenario in which something has exactly zero probability. A particular future event might have a vanishingly infinitesimal probability of occurring—say, odds of one in a googleplex, for example—but that probability still is non-zero. Therefore, if the many-worlds interpretation of QED is accurate, then there is always some universe in which even that incredibly unlikely event occurs. That is the powerful and sobering (not to mention seemingly absurd) implication of the many-worlds interpretation of QED." -- Ryanaxp (Talk:Quantum Suicide)

And you were correct in doing so. :) - green_meklar 01:55, 12 October 2006 (UTC)

[edit] Study in sexism

For a small but interesting example of gender stereotyping in action, take a look at the history of this article. Note the way that the physicist in the thought experiment -- who was originally female when I added her to the article -- gradually became male. Interesting stuff. -- Derek Ross | Talk 06:28, 11 October 2006 (UTC)

Hardly surprising. People use he even for sex-neutral terms like citizen, and physicists are predominantly male.[1] -- Schaefer (Talk) 14:59, 11 October 2006 (UTC)

I understand the reasons. I just thought that it was a good illustration of the phenomenon. Hence this note. -- Derek Ross | Talk 23:34, 12 October 2006 (UTC)

According to the Oxford dictionary, the pronoun "he" is also used for living beings of unknown gender. 24. 10. 2006

[edit] Some ideas

I have a few ideas I've come up with on the subject of quantum immortality, so I decided to run them by here and let someone add some information to the article if they feel it belongs there.

Guaranteed quantum immortality

I haven't read this anywhere else, it's just my own idea. Is it possible that, from a subjective point of view, quantum immortality is guaranteed? What I mean is, since nothing is 100% certain from a subjective point of view, happening to exist in a universe with randomness may itself be a part of quantum immortality. In other words, how it currently stands is that you have to experience a universe where quantum randomness rolled 'survive'. Is it possible that you also have to experience a universe where subjective randomness rolled 'randomness' and 'multiple world'? This is pretty deep philosophy here, getting to the limits of the english language, but I'd like to know who thinks this follows from the same logic as the basic principle of quantum immortality.

A multiple worlds society

One of the problems with quantum immortality is that you can never prove it to anyone else. Even if someone else is lucky enough to remain in universes where you miraculously survive several times, probability dictates that as time passes, the chance of them seeing you die (and thereby fail to prove quantum immortality to them) approaches one. However, it may well be possible someday to prove the multiple worlds model (possibly through the theory I described above, among other methods). If this is the case, it has some profound implications for our society and philosophy. Not only does it make quantum immortality that much more likely, but it also essentially eliminates morality: Since everything that could have happened did happen in some other universe, there is nothing you can do to prevent any of the total amount of suffering that ever happens, all you can do is get yourself into a certain universe if you want. This means that there is no point being altruistic, and that everyone should logically just try to get themselves into the best possible universe for them. It may sound cold and heartless, but it makes sense and is not immoral. I'm not sure if this idea belongs in this article, though; it may go better in the many-worlds interpretation article.

Also, is it just me, or do any of you atheists out there find it funny that all those religious people who expected to go to Heaven all their lives will never get to die? :P - green_meklar 01:55, 12 October 2006 (UTC)

Ah. Improper. Technically speaking, the quantum immortality theory only states that your consciousness cannot end. If there is an afterlife, then the theory allows for death, as long as one continues to exist in some form. Therefore, quantum immortality does not actually prove immortality of the body, merely that of the soul. -LB

That is correct. However, as an atheist, I am assuming for these purposes that neither Heaven nor Hell actually exists, and that if there is any such thing as an afterlife, it is almost certainly not like the christian/muslim/jewish/buddhist/hindu/whatever afterlives. In fact, if shifting someone to an afterlife is an easy way to satisfy quantum immortality (and if my proposal of guaranteed quantum immortality is correct, that might well be the case), then there might be a very good chance that all of us, including religious people, will end up in said afterlife eventually- and of course, the same thing applies there, so we could end up living through an infinite chain of universes, of which this is only the first!

You know, this kind of speculation almost makes you want to hurry up and die just to see what happens... ;P - green_meklar 20:18, 25 October 2006 (UTC)

[edit] Quantum Suicide

This is the same as Quantum Suicide: should we merge the articles? A lot of the text is the same. I've added a merge tag. --Michael C. Price ^talk 20:14, 18 October 2006 (UTC)

• I support the merge, but don't feel like doing all of the work. -- Tiak 05:33, 11 January 2007 (UTC)

[edit] Immortality and the issue of morality,quantum +cyclic

There is one good thing about mortality, and that is an OFF switch and free will, you did not have an option about whether or not you were born, you're here now and you're stuck with it for as long as you live, if you don't like it then there is the suicide option (an OFF switch) and you'll die anyway, there is no avoiding that.

But everyone (except perhaps some psychotics and religous fanatics) are scared of death, generally, and our mortality does prevent us from doing silly things and does seem to keep a certain amount of order within chaos.

I don't like the immortality mindset, if you believe you'll never die and cannot be hurt by anything or anyone you would develop psychotic illness pretty damn quick, "i'm immortal so it is OK to let off these nuclear warheads and kill everybody" "i'm immortal so it's ok to rape women because any punishment for an evil act has no effect on me"

Basically immortality rips apart the 10 commandments and any government enforced laws, because they do not apply to you, emotions are fairly pointless when you've been around a long time.

Why should i care about other peoples feelings when there is only myself: a GOD unto everyone else, if i am an immortal then the world revolves around me and works for me alone and nobody else, if i want you to die, you shall die.

Once you are immortal and know it, then YOU ARE GOD.

Maybe it is not as easy as quantum immortality suggests, there is a theory of a cyclic universe in a expanding-contracting-expanding etc etc to infinity, it is one big time bouncing machine that may repeat the same history over and over, lets say joining this with quantum immortality gives you many universes all repeating their same individual history over and over , maybe, MAYBE joining the two theorys could give you a conclusion that we are all born again doomed to repeat our lives over and over, and maybe from a personal reference point we remember our past life, but no one else does. With that you can avoid sillyness, such as "what about when i get to be a billion years old and am just a brain floating in space" not gonna happen, just to put some sense in it, i would suggest simplyfying it to a time bounce in a cyclic universe, but with a personal memory of a past life in the same physical body born from the same mother and father and same history.

The reference and physics of quantum immortality can essentially stay intact, especially the personal reference: everybody is immortal from their own viewpoint but no one elses.

So as soon as you die, you'll wake up looking at your mum in hospital, while they remove you umbilical cord "damn" you'll be thinking "not this crap again".

The real flaw with this i guess, would be the assumption the universe we (or should i say I AM IN) has not cycled before, if it has cycled before, i do not have memory of the last time, there is (currently) no "before i was born" stories to tell.

The problem is time+memory, the many worlds theory seems by itself to resolve the paradox of memory, when you go back in time and change something, if you change it, it wouldnt happen so in the future you'll have no memory of it and no desire to change it, of course many worlds fixes this in the sense of universes being linked to alternate probabilitys. If the universe were a time machine, it's the consiousness variable, time and memory! an individual knows if they have time travelled, even if no one else does.

MARK S.H (UK)82.13.42.65 11:26, 24 October 2006 (UTC)

Uh, it seems that, like those people up above who want to make everybody immortal in the same universe, you have a number of misconceptions. Let me clear them up.

"I don't like the immortality mindset, if you believe you'll never die and cannot be hurt by anything or anyone you would develop psychotic illness pretty damn quick, "i'm immortal so it is OK to let off these nuclear warheads and kill everybody"

"i'm immortal so it's ok to rape women because any punishment for an evil act has no effect on me"

Basically immortality rips apart the 10 commandments and any government enforced laws, because they do not apply to you, emotions are fairly pointless when you've been around a long time."

First, the ten commandments are based on the Bible, so as an atheist I don't see them as a very accurate representation of morality. And laws are based on what some corrupt government officials decided, so even for a christian like you, it should be obvious that they are not necessarily an accurate representation of morality.

Second, 'immortal' doesn't equate to 'invincible'. It may be impossible for you to die, but you can still be caught, locked up, made to live on bread and water, physically disabled, tortured, etc. This, along with the possibility that quantum immortality doesn't actually work, is a good reason not to go around committing all sorts of evil deeds just for the hell of it.

Why should i care about other peoples feelings when there is only myself: a GOD unto everyone else, if i am an immortal then the world revolves around me and works for me alone and nobody else, if i want you to die, you shall die.

Once you are immortal and know it, then YOU ARE GOD.

Not only can other people still lock you up and torture you if they like, but you are only immortal in your universe. To everybody else, going on a criminal rampage will only be a minor annoyance for a few days until they catch you and kill you and continue their lives.

"So as soon as you die, you'll wake up looking at your mum in hospital, while they remove you umbilical cord "damn" you'll be thinking "not this crap again".

The real flaw with this i guess, would be the assumption the universe we (or should i say I AM IN) has not cycled before, if it has cycled before, i do not have memory of the last time, there is (currently) no "before i was born" stories to tell."

Right. If the universe had cycled many times before, we should have memories of our past lives. The whole point is that each one of us is, right now, only at the very beginning of the eternity that lies before us (and of course, none of us will ever see anyone else get past that beginning). Note that this does not violate the Copernican Principle because everyone has to go through that beginning, it's impossible to start in the middle. Additionally, it seems highly unlikely that, of all possible survival scenarios, quantum immortality would at any given point choose the one where you return to being a baby in a younger copy of your own universe, and besides, the existence of dark energy means that our universe probably won't collapse in a Big Crunch. - green_meklar 20:18, 25 October 2006 (UTC)

[edit] What about the Biblical long lived people? Like Methuselah

While reading this I had an idea that might be silly...I was wondering that one might notice the QI effect by observing a very old individual, say 150-200 years who seems to have found the fountain of youth. Given the 6 billion or so of creatures on earth it is extremely unlikely for that to happen to ME. However one could then ask the question: if we admit the Bible being at least partially correct that there were only two people on Earth in the beginning, and only few more in the following centuries wouldn't QI explain while THOSE people noticed such an unusual life span among them? For example the Bible mentions that Adam lived over 900 years. So I guess from a mathematical standpoint my question is: If the Earth has a very limited number of people is it plausible to assume that there is a universe where some of them notice the QI by noticing the huge lifespan? Of course the flaw here is that for that kind of universe 900 years of living would not be any unusual news. But I still wonder if the religion is nothing but undiscovered science. (Chaoserrant 01:34, 17 November 2006 (UTC) 8:29PM Nov.16.2006)

Quantum immortality doesn't work that way, though. It only applies to you as the observer; the other people around you are perfectly free to die with normal probabilities. Of course, from their perspective it's the other way around; they perceive themselves as immortal whereas everyone else around them (including their version of you) eventually dies of various causes. This is a result of the many-worlds interpretation, we all wind up diverging into different worldlines. Bryan 06:05, 17 November 2006 (UTC)

Am I correct in saying that in a much smaller number of worldlines we all survive?

Yes. Probably still a "near" infinite number, though. --Michael C. Price ^talk 09:04, 23 November 2006 (UTC)

[edit] which survivor-states are more probable?

just a thought: "...the future that an observer finds themselves in is determined by probability- since some futures are more likely there will be more universes that take that path than less likely ones- considering that a conscious observer is a very complex ordered system whose structure and evolution are heavily constrained by very specific causal relationships with the observer’s environment- virtually all forms of death will always happen to every instance of the observer in a particular situation- if a mountain falls on you it is also falling on every instance of you in other universes were your structure is similar enough for all of your parallel selves’ neural systems to interfere with each other- also death never happens instantly- there is a complex gradient of changes in the mind’s electrochemistry as the body dies likely causing a mind’s final states to diverge too far from the parallel versions which did survive and thus no similar adjacent universes for the conscious circuit to shunt to- so only in cases where the cause-of-death is like a ‘Schrödinger’s Cat Experiment’ with some minute random factor that amplifies quantum effects would an observer seem to have ‘survived’ and continued their lives- instead- given what we know about universal computation and technology it is far more probable [by centillions of orders of magnitude] that an observer at death would experience waking up directly in some computational resurrection/ reconstruction by an advanced intelligence/society actively looking to restore dead beings for whatever reason- most probably in one of the futures of the observer’s own world..."

in other words- considering the much more likely possibilities of technological resurrection- it seems that with a certain-death type event there are always far- FAR more universe-states which lead to a future reconstruction by the observer's decedents- even alien archeologists- than miraculously surviving in the same frame of reference- in fact given that EVERY possible future of an intelligent being's society must happen in MWI- then there must ALWAYS be some futures which achieve and perform technological resurrections/reconstructions- so the probability must be close to unity for every sentient being in the universe-

/:set\AI - dec 4 2006

[edit] Can there be only 2 different branches?

I do not think there can be only 2 branches because there are at least 4 different chances. 1. The gun is triggered and he dies. 2. It isn't triggered. 3. It is triggered and he is hurt but lives. 4. It is triggered and he just happens to be out of the path of the bullet when it is fired and it hits the wall behind him. Just a thought. Dylan Telfer, December 11th, 2006

The idea of branches is just for ease of thinking. Separate branches don't actually exist. In fact there is a whole spread of possibilities. for instance in your example there are many, many different possibilities corresponding to how much injury the bullet did, or by how much it missed -- far, far more than 4. But the possibilities aren't split into branches. Each merges imperceptibly into its neighbours. -- Derek Ross | Talk 16:24, 11 December 2006 (UTC)

[edit] The immortal amoeba

The idea of quantum immortality is similar to considering the amoeba immortal. If amoeba's had minds, they would likely consider that both of the offspring of reproduction by fission were the original amoeba. Splitting off into parallel universes is similar to reproduction by fission. Any amoeba could claim not to be merely a descendant of the original amoeba, but actually to be that amoeba. Now, amoebas do die, and it would probably be pretty cold comfort to those dead amoebas to know that copies of themselves still live. If I tried this experiment, there might be a copy of me that goes on living, but *I* would be dead. In any case, there would still be the possibility that the gun had merely malfunctioned an unlikely number of times. --RLent 23:07, 19 December 2006 (UTC)

[edit] Nuclear weapon example

Is this example appropriate? I can understand the gun experiment, but can anyone reasonably claim there would be any universe where a person can survive a direct explosion of a nuclear weapon? I'm not certain of the physics in question, but isn't this about as likely as light travelling between stars instantly? Surely the survival of the person would be impossible given the intense heat, radiation etc? Richard001 21:21, 2 January 2007 (UTC)

This issue is already explained above under the heading "Removed info". -- Schaefer (talk) 23:13, 2 January 2007 (UTC)

[edit] Mathematics of QI

Giving this a little more thought, it seems to be a probability experiment mimicking the number 0.999... - in any universe there will have been a finite number of events in which the survival scenario prevailed, but for immortality an infinite number of survival scenarios is needed, not just a large number. This is like starting off with a probability of 0.5 of living, dividing by 2 an infinite number of times. This would produce 0.000..., which is the same as 0, just as 0.999... is the same as 1. Is this not mathematical proof that there can be no such thing as quantum immortality? Richard001 21:32, 2 January 2007 (UTC)

This talk page is for discussing changes to its associated Wikipedia article. It is not a general forum for discussing new insights into quantum immortality. That being said, you may wish to read The Everett FAQ. -- Schaefer (talk) 23:43, 2 January 2007 (UTC)

[edit] Need another example

How do you resolve that human beings apparently die after no more than 120 years when their body or brain stops working? Quantum immortality is only clear in these few extreme and violent cases. 12.41.40.20 20:22, 3 January 2007 (UTC)

• I don't think that's any sort of exemption, it fits within the idea perfectly. If probability predicts that the vast majority of times someone will die before the age of 120, in the vast majority of existing universes everyone else will experienced someone's death before the age of 120. As one gets older the probability of essential parts of someone deteriorating rise, and the chances of them dying as a result of this deterioration increases as well, but this population never reaches 1, simply a number very close to 1. --Tiak 05:40, 11 January 2007 (UTC)

[edit] David Lewis argument flawed?

Would the physicist be able to avoid the dreary fate of "survives terribly disfigured, badly disabled, and so on" if he adopted the plan of committing suicide (or quantum suicide) every time he found himself in a future that was suboptimal? This may significantly decrease the number of futures that the physicist survives to, but among those futures wouldn't the physicist be in good shape with high probability?

Quantling 20:47, 8 January 2007 (UTC)

Well, this is only true in such scenarios that one is more probable to survive, be disfigured, and be both cognitively and physically capable of suicide. In the common examples, such as the gun and the nuclear explosion, the probability is that the disfiguration will either disallow free movement or the cognitive ability to rationally consider ending one's life. So it's still rather valid miraculous survival + lobotomization, miraculous survival + parapeligia, and miraculous survival + amputeeism all are more probable than unscathed miraculous survival in most situations. --Tiak 05:59, 11 January 2007 (UTC)

[edit] Does Quantum Immortality suggest this?

Because QI suggests the possiblity of eternal life from one's own perspective, wouldn't we all eventually be in a universe where we would be infinitely old and decrepit?

Example: I die of heart failure at age 70 in one world, but I continue to live in another and die of cancer at age 82, but I continue to live in that world and die of renal failure at age 85 and so on. Wouldn't death challenge me more frequently and I would keep evading it while becoming infinitely old?

69.160.1.4 07:52, 28 January 2007 (UTC)

• Perhaps. But suppose they transfer your mind to a computer for your best interests or something like that. Or suppose they remove your brain and put it in someone else's body for some reason.

[edit] resolution

QI only says that consciousness is eternal, not the body. This is essential to understanding it. A QI-action-man only observes himself as eternally conscious from the point of view of his OWN time frame. Therefore, if you pointed the gun at your heart and pulled the trigger, in 99 999 999 universes you may be dead, but in 1 universe your body is frozen in liquid heluim only to be revived 10 000 years in the future. From the point of view of the QI action man - one second he was pulling the trigger, the next second he is waking up in a hospital 10 000 years in the future. But why stop there; there is one in googleplex chance that a billion billion years from the point of pulling the trigger, a few billion molecules spontaneously (by chance) come together and form the exact same man, on an alien planet (or just make the brain of the man in a special jar made by aliens).

So, the discussion so far makes one glaring mistake - by assuming an equivalence between "physical being" and "conscious being". The two are separate - you "are" when you are asleep, but you are not conscous - therefore - in the time frame of any man - periods of sleep do not count as "being" - being ends with falling asleep and resumes after waking up. Likewise, conscousness can very well end at death, only to resume (by chance) at some future moment. It may well be that it is much more likely to be revived by aliens a billion years from now, than to have a gun malfunction 1000 times in a row. Therefore "survival universes" in the distant future will dominate (i.e. might be more numerous) than universes where the body survives. Which brings us to the lovely notion of judgment day, when all dead arise, at some point in the future :)

Important consequences: it must be pointed out that the only possible survival scenarios are the ones that will be psychologically acceptable by the QI-action-man. For instance, a survival involving a future universe full of angels, clowds and harps might drive some insane (i.e. unconscious) so people who dont believe (or cannot believe) in such after-life scenarious will only end up in other after-life scenarious (that they may find acceptable). Likewise, being the only survivor of a nuclear holocaust may also eventually drive that person insane, which means that the universe will conspire to keep enough "others" alive (and so "judgement day" happens to lots of people in a single universe, rather than just one). Therefore, it is important TO CHOOSE NOW, what after-life scenarios one finds acceptable. And vice versa - religious zealots fervently believing in only one possible paradise (or hell) irrevocably find themselves there, after death.

Most people will probably find acceptable being revived in the future (out of a liquid hellium vat), which means that they will not see themselves physicaly surviving 1000 consequitive gun shots to the heart.

The only way to phisicaly survive without going through death and rebirth is to be a fanatical atheist, and to ensure (somehow) that any cause of death at any future moment will always result in cremation. This means that the universe "here and now" will conspire to bring scientific discoveries extending life-span and eventually physical immortality for all.

..Brrr, dark stuff, this QI-thing.

Cacxo 16:41, 7 February 2007 (UTC)

This is a Wikipedia talk page. Please try to use it for discussing changes to its associated article, not as a general forum for discussing the article's subject. -- Schaefer (talk) 22:50, 7 February 2007 (UTC)