Search FQXi


If you are aware of an interesting new academic paper (that has been published in a peer-reviewed journal or has appeared on the arXiv), a conference talk (at an official professional scientific meeting), an external blog post (by a professional scientist) or a news item (in the mainstream news media), which you think might make an interesting topic for an FQXi blog post, then please contact us at forums@fqxi.org with a link to the original source and a sentence about why you think that the work is worthy of discussion. Please note that we receive many such suggestions and while we endeavour to respond to them, we may not be able to reply to all suggestions.

Please also note that we do not accept unsolicited posts and we cannot review, or open new threads for, unsolicited articles or papers. Requests to review or post such materials will not be answered. If you have your own novel physics theory or model, which you would like to post for further discussion among then FQXi community, then please add them directly to the "Alternative Models of Reality" thread, or to the "Alternative Models of Cosmology" thread. Thank you.

Forum Home
Introduction
Terms of Use

Order posts by:
 chronological order
 most recent first

Posts by the blogger are highlighted in orange; posts by FQXi Members are highlighted in blue.

By using the FQXi Forum, you acknowledge reading and agree to abide by the Terms of Use

 RSS feed | RSS help
RECENT POSTS IN THIS TOPIC

ahlinya benjolan: on 7/16/18 at 6:07am UTC, wrote ' target='new'>khasiat walatra propolis Qnc jelly gamat Walatra bersih...

songjoong df: on 1/2/18 at 8:42am UTC, wrote jual qnc jelly gamat di magelang jual qnc jelly gamat di mataram jual qnc...

songjoong df: on 12/27/17 at 6:31am UTC, wrote cara menjadi reseller qnc jelly gamat Cara Menjadi Agen Qnc Jelly Gamat ...

Anonymous: on 3/13/10 at 23:50pm UTC, wrote Anthony: I believe that you're focusing in too much on this hypothetical...

paul valletta: on 5/14/07 at 11:28am UTC, wrote There is another constraint, which may be intepreted thus, I have a proven...

paul valletta: on 5/10/07 at 23:10pm UTC, wrote WOW! either I hit the hidden variable "re-copy" button, or the transporter...

paul valletta: on 5/10/07 at 23:08pm UTC, wrote I would not hesitate to enter the "transporter", even without prior...

paul valletta: on 5/10/07 at 22:58pm UTC, wrote I would not hesitate to enter the "transporter", even without prior...


RECENT FORUM POSTS

Georgina Woodward: "Hi Ian, I've been thinking about choice of carrot or pepper. Behaving in a..." in Measuring Free Will: Ian...

Lorraine Ford: "(continued) 3. “…so this is what defines a free choice : the Zeta..." in Measuring Free Will: Ian...

Georgina Woodward: "What is happening in material reality provides the connection to inertia...." in Bonus Koan: Distant...

Georgina Woodward: ""We saw early on that as conformed by countless experiment, there is no..." in Bonus Koan: Distant...

andrea gonzalez: "Interesting stuff to read. Keep it up. If want to collect free gift card..." in Memory, Causality and...

Joe Fisher: "Dear Dr. Kuhn, Today’s Closer To Truth Facebook page contained this..." in First Things First: The...

Poker Online: "https://www.jakartapoker.net/" in Downward causation:...

Enquire us: "Your Ro system desires regular maintenance to confirm it’s continually in..." in Agency in the Physical...


RECENT ARTICLES
click titles to read articles

First Things First: The Physics of Causality
Why do we remember the past and not the future? Untangling the connections between cause and effect, choice, and entropy.

Can Time Be Saved From Physics?
Philosophers, physicists and neuroscientists discuss how our sense of time’s flow might arise through our interactions with external stimuli—despite suggestions from Einstein's relativity that our perception of the passage of time is an illusion.

Thermo-Demonics
A devilish new framework of thermodynamics that focuses on how we observe information could help illuminate our understanding of probability and rewrite quantum theory.

Gravity's Residue
An unusual approach to unifying the laws of physics could solve Hawking's black-hole information paradox—and its predicted gravitational "memory effect" could be picked up by LIGO.

Could Mind Forge the Universe?
Objective reality, and the laws of physics themselves, emerge from our observations, according to a new framework that turns what we think of as fundamental on its head.


FQXi BLOGS
August 25, 2019

CATEGORY: Blog [back]
TOPIC: Quantum Grantmaking [refresh]
Bookmark and Share
Login or create account to post reply or comment.

FQXi Administrator Anthony Aguirre wrote on May. 1, 2007 @ 18:00 GMT
At about 1 AM GMT on April 20, 2007, the Universe split into at least 32,768 nearly-identical copies. How? And did it really?

The event was precipitated by yours truly gathering a quantum-mechanically random number between 1 and 10,000. Generating this number required making at least 15 quantum measurements, each yielding one random bit. In the course of each measurement, a solid-state...

view entire post


Bookmark and Share
report post as inappropriate


Member Antony Garrett Lisi wrote on May. 9, 2007 @ 01:39 GMT
Have you ever been under global anesthesia? If so, when you came to, how did you know you were still you? You probably asked yourself questions like "where am I?" and the answers came back to you, from memory, as an internal dialogue. This, our memory and internal dialogue, is how we perceive our "self." If we were to make perfect copies, classical or quantum, and these selves were to ask themselves, "am I me?" the answer would come back: "yes, of course!" to both copies. It doesn't matter that there was an interruption in the stream of consciousness, any more than it mattered that your stream of consciousness was interrupted by anesthesia -- you still came back as you, and you know it because of how your memories and internal dialogue proceeded from that point forward.

If the duplication was done, and one of the copies was killed without ever being returned to consciousness, the other copy would never be the wiser -- you'd just think you were put under then brought back.

We're just not used to our classical worldline branching, so it seems bloody weird to think about.

And, umm, at one point there was another possible me very happy to receive a minigrant for a new snowboard, but I'll never get to ride it since I never applied.

Bookmark and Share
report post as inappropriate


FQXi Administrator Anthony Aguirre wrote on May. 9, 2007 @ 02:46 GMT
Garrett,

I agree that it's perfectly clear that both 'Anthony's will think they are 'me'. The question is: imagine the machine is sitting there in front of you. Knowing that the next moment there will be exactly two 'Garret's, one of which is suffering an agonizing death, would you step in or not?

If yes, how do you explain your decision to the really angry (and horribly dying) Garrett?

If not, how could you believe in the Many Worlds Interpretation? (To make this more poignant, you could get up a quantum-gun that, when you pull the trigger, fires with P=0.00000000001, and aim it at your foot. Most people after seeing this gun go 'click' a many, many times would be willing to 'shoot' it at their foot for, say $50. But if you believe MWI, but would *not* step in the described machine, I think you'd be crazy to do this).

Bookmark and Share
report post as inappropriate

Anonymous replied on Mar. 13, 2010 @ 23:50 GMT
Anthony:

I believe that you're focusing in too much on this hypothetical example. First, to answer your question, I would not step into the machine because it is designed to produce a copy that would be tortured for certain. The only thing that you've said is that there is a 99.999999%% chance that it won't be you. That means that there is an equal chance that it will be the "copy" that is harmed. I prefer we remove this scenario to the real world.

First, I believe in the many-worlds interpretation and have done so since 1991 for reasons that I won't go into here. Being a believer, and someone who has taken many risks between those days and now, I would view the outcomes of those risks as a distribution pattern of probabilities, hopefully with failure that would be fatal, at the extreme low end of the distribution. But that is how life works. The key is to avoid taking chances that have a high probability of catastrophic results, because you don't know where you will be along that probability distribution.

The dial, on the machine that you described, is of course the key to the whole situation - the control of probability so that the outcome that we wish to observe is the one with the highest probability that will be observed by us. Of course, another description for such a process would be engineering reality.

I think that it would be impractical to constantly think in terms of the fate of our copies, based on every decision that we make. Besides the fact that oft times our copies may suffer because of things beyond our control, for which we might not be adversely effected, sometimes, we are that copy that gets the bad end of the stick, the raw deal, what have you. It is then that we experience that sense of regret, that "what if", that "if I had only..."

The many-worlds interpretation is an amazing theory, one which I am glad has gained acceptance over the years. Perhaps I will discuss it more later, as the opportunity presents itself.

Bookmark and Share
report post as inappropriate


Member Antony Garrett Lisi wrote on May. 9, 2007 @ 04:23 GMT
I would have to make a decision on the desirability of the experiences of my future selves -- even though these experiences would not be shared amongst the different copies. If one of the copies is just to be snuffed out, or never revived, it's an easy decision -- since one never experiences being dead. My worldline would have a tiny dead-end stub, but otherwise continue with a happy life,

(:-D

|

|

$

\ x

V

|

|

(:-)

If one of the me's was to be painfully tortured, I would have to weigh the negative value of that experience against the reward and decide. I'm a pretty happy guy, so it would have to be a big reward... here you can see a future me with a double chin (and, of course, still bald),

(:-))

|

| x

$ (:-(

\ /

V

|

|

(:-)

Even though the future copies do all exist, independently, the rational choice should still be based on a weighing of cost vs benefit -- effectively the same as when one uses likelihoods of possibilities to make a decision.

This same decision process would apply to being paid to maybe shoot myself in the foot.

There is a difference between the classical copying and quantum splitting though: In the classical copying, I'd have to take into account the guilt felt by the surviving me, who watched the other me suffer while telling him it was worth it (thus the double chin, brought on by guilt induced binges). In the quantum splitting, it's best not to worry about your other, effectively nonexistent selves -- since they can't effect you (unless you're very small) -- and just role the dice.

Bookmark and Share
this post has been edited by the author since its original submission

report post as inappropriate


Anonymous wrote on May. 9, 2007 @ 05:29 GMT
Ah, I just thought of an amusing way to think about copying yourself:

Pretend you're an Amoeba.

Pity they're not talking... no, wait, that's probably a good thing.

Bookmark and Share
report post as inappropriate


FQXi Administrator Anthony Aguirre wrote on May. 9, 2007 @ 14:25 GMT
Garrett,

Ahh, but do the feelings of your 'tortured' version count as much as the non-tortured one? Probably you would say yes, and this is the whole point: in MWI, we are supposed to make decisions (such as whether to do a measurement that could, with tiny probability, cause our painful death) on the basis of the quantum probabilities. But tell that to the copy who is asphyxiating. :-o

Bookmark and Share
report post as inappropriate


Member Antony Garrett Lisi wrote on May. 9, 2007 @ 16:24 GMT
(btw, it was another me who made the amoeba comment)

Yes, the tortured version counts as much, but should be weighted by its probability. Drowning is a terrible thing to experience (I've come close) so the motive would have to be very strong -- a girl would need to be involved (otherwise it's hard to be that crazy).

In QM, and in classical Bayesian probability, our other versions don't effect us -- so, effectively, they don't exist and we shouldn't feel guilty about them.

Bookmark and Share
report post as inappropriate


Anonymous wrote on May. 9, 2007 @ 17:16 GMT
Garrett,

Sorry, the question was in the context of the teleporter machine, or MWI, in which both copies exist for certain.

I agree that in a Copenhagenesque view, the probabilities of one thing happen versus the other matter very much.

A

Bookmark and Share
report post as inappropriate


Member Antony Garrett Lisi wrote on May. 9, 2007 @ 18:14 GMT
Sure, we just have to think like amoeba's: our current self will be experiencing both outcomes, separately. There is a small difference though: In the teleporter case, we have to live with the fact that our other version died in our branch of reality; but in the MWI case our other version died in a reality separate from ours. This means our decision in the MWI case should be the same as for any classical gamble -- since the other selves effectively won't exist for each other. In the teleporter case, we'll be involved in a murder.

Bookmark and Share
report post as inappropriate


Member Antony Garrett Lisi wrote on May. 10, 2007 @ 00:17 GMT
(Heh, I had posted two replies. But one of them just vanished. I guess I feel OK with that.)

Bookmark and Share
report post as inappropriate


Count Iblis wrote on May. 10, 2007 @ 14:06 GMT
"At about 1 AM GMT on April 20, 2007, the Universe split into at least 32,768 nearly-identical copies. How? And did it really?"

Well, if we are going to treat the observer not as external but internal to the multiverse and subject to the laws of quantum mechanics (leading to the copies of the same observer), then we must also describe the decisions the observer makes also using these laws.

So, it should be clear that the split into the "32,768 nearly-identical copies" was not really caused by a choice someone made that had it not been made would not have resulted in the universe splitting, because Anthony himself is part of the multiverse and there exists an Anthony who decides to have a lottery and there exists an Anthony who makes a different choice. These different Anthonies exist a priori with some amplitudes in the multiverse and nothing can "change" that fact.

So, the spittings are just artefacts of looking at special sectors of the multiverse and then comparing that sector with a another sector you obtain by applying the time evolution operator. If you apply the time evolution operator on the entire multiverse you would probably see no splittings at all because the entire multiverse could well be an exact eigenstate of the Hamiltonian.

Bookmark and Share
report post as inappropriate


FQXi Administrator Anthony Aguirre wrote on May. 10, 2007 @ 16:15 GMT
Garrett:

Yes, those superpositions collapsed. (or did they just decohere....)

Count Iblis:

I agree that if we assume that the universe is in a definite quantum state evolved by some fixed Hamiltonian, then there is no place for 'branching' of the cosmic wavefunction, but rather an evolution that describes one 'Anthony' and then, later, many. But as far as I (Anthony) am concerned, this certainly is a 'branching.' So whether the 'world splits' depends on how self-centered you are...

Bookmark and Share
this post has been edited by the forum administrator

report post as inappropriate


paul valletta wrote on May. 10, 2007 @ 22:58 GMT
I would not hesitate to enter the "transporter", even without prior knowledge of the favourable probability constraint.

I would rely on the fact and knowledge based on current "experience", I would know that I would STILL remember my/the past, wheras my copy would have a 50/50 chance of remembering the/it's future!

I would retain a "current" past history, I am,thefore I am?

Bookmark and Share
report post as inappropriate


paul valletta wrote on May. 10, 2007 @ 23:08 GMT
I would not hesitate to enter the "transporter", even without prior knowledge of the favourable probability constraint.

I would rely on the fact and knowledge based on current "experience", I would know that I would STILL remember my/the past, wheras my copy would have a 50/50 chance of remembering the/it's future!

I would retain a "current" past history, I am,thefore I am?

Bookmark and Share
report post as inappropriate


paul valletta wrote on May. 10, 2007 @ 23:10 GMT
WOW! either I hit the hidden variable "re-copy" button, or the transporter "me" is falsifying my previous post!

Bookmark and Share
report post as inappropriate


paul valletta wrote on May. 14, 2007 @ 11:28 GMT
There is another constraint, which may be intepreted thus, I have a proven history, before copies were made and placed into the transporter. The "copies" history are dependant upon the transporter, they have no history prior to their creation?

Each destination has to be contained within the copies "known" historical existence, there was no point of existence prior to their creation?..so each prefered path (destiny route), is pre-chosen, and both are in a virtual future.

I would not experience any of the "destiny" outcomes, the fact is that the Transporter acts as a cut-off point for both copies that enter?

Bookmark and Share
report post as inappropriate


Login or create account to post reply or comment.

Please enter your e-mail address:
Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.