[Harri (OP)]

You have to admit, whether you believe it or not, that the Quantum Suicide Game is intriguing. Your quantum gun against your head goes click click click click ... and you're relieved. Because if it went click click click bang ... you wouldn't be alive to feel relieved!

What if your cancer diagnosis was also determined by the QSG ? A positive spin and you're relieved ... a negative spin and you have a death sentence.

In both instances there is a YOU that survives. Along with the other YOU's that are surviving all kinds of other life threatening scenarios I guess?

So then at  the end of YOUR natural life you die. Do all the other YOU's die at the same time as well? Let's say YOUR heart stops on your death bed. If another you is on the golf course does he drop down dead too? And all the other YOU's drop dead as well ?

Or is it a case of the last YOU standing?

[alancalverd]

You have a death sentence anyway. It's just that most people don't know when or how it will be enacted. There is no evidence of the existence of other you's - "many worlds" is just a mathematical tool for assessing probabilities.

[Bored chemist]

In a many worlds scenario the word "You" is not well defined.

[Halc]

As B-C says, MWI does not support the concept of identity of objects, be they living or not.
I have all the respect in the world for Tegmark, but he's got an incompatible preferred-world dualist attitude in his description of this quantum suicide machine.  The two views are not compatible.

[Harri (OP)]

It's a genuine concern of mine, taking into consideration my 62 years on this planet, that I have and always will have an innate inability to tackle anything mathematically based. For as many of my 62 years as I can remember I have always been interested in the BIG questions. That most of the answers to these questions are founded on mathematical outcomes then I always will come to a conclusion that is perhaps too simplistic, based on thought and popular current thinking rather than hard facts. I think this might be the case here.

It's strays from my original question but do you think it is possible, in the world of quantum mechanics for instance, to get a firm grasp on the facts of the matters in question without a mathematical foundation?

Halc, if I may, what exactly do you mean by ... 'incompatible preferred-world dualist attitude' ... could you specify which 2 views are not compatible?

[jeffreyH]

You die. If you are buried then other lifeforms feed on you. They consume your energy for their own use. If you are cremated all your energy goes up a chimney. This continuous cycle continues until all species become extinct, the planet loses its atmosphere and water. Then the sun expands to consume the planet. Ultimately many worlds are consumed this way until the ultimate heat death of the universe. And they all lived happily ever after.

[Halc]

It's strays from my original question but do you think it is possible, in the world of quantum mechanics for instance, to get a firm grasp on the facts of the matters in question without a mathematical foundation?

Well, I do happen to have a reasonable mathematical background, but I certainly cannot follow much of the mathematics of either quantum or relativity theories posted in the various papers. That doesn't stop me from accepting or trying to understand the conclusions of those that can.

So I happen to know relativity fairly well, and I know many of the differences (if not the deep details) of the various quantum interpretations, all of which are essentially philosophy, not science, since they lack any empirical test to distinguish them.

[Halc]

Halc, if I may, what exactly do you mean by ... 'incompatible preferred-world dualist attitude' ... could you specify which 2 views are not compatible?

All living things have a sense of identity, a concept of 'me', the benefit for which decisions (like drawing the next breath) are made.  If the thing doesn't have this basic sense, it isn't fit, and it gets selected out.  That identity has sort of evolved into a sense of there being a separate experiencer of the body, which is the dualism (the other of the two views) I mentioned.  All the religions seem to flourish by making promises not to the mortal person, but to the supposedly immortal experiencer of that person.  Anyway, it is incompatible with any interpretation (MWI being one) that has no concept of identity.

There are all these worlds, some of which have a person in it that claims the same common ancestor (say you a year ago) as do you.  'You' can't be both of them, so which is the original?  Who experiences the other ones if not the thing that experienced you a year ago?

Don't need MWI to demonstrate this.  Suppose a baby is conceived: a fertilized egg.  In the course of the next day, the egg splits and separates rather than holds together.  That happens sometimes.  Now there are identical twins (fraternal twins are a different story).  Which of those two twins is the original?  Which is the new person? If you believe in this immaterial experiencer, at what point does it get assigned to either baby?  MWI is like that, except it happens many times a second continuously, so what you think is 'you' a minute ago is actually somebody else.

Many other interpretations of QM have no problem with a thing holding onto identity like that, so those interpretations are more compatible with say the religions that make all the promises to such identities.

Oh, and by 'preferred world physics', I mean the assertion that there is one world (this one) that is experience by 'you' (the identity), leaving apparently no identity entity to experience the people in the other worlds.  Tegmark's quantum suicide machine was meant to force that preferred observer to always take the path where the body isn't imminently destroyed.  Notice he hasn't enough faith in his belief to actually perform the experiment.

[Harri (OP)]

I'm beginning to think there is an effort to carry over into the world of relativity ... the things that happen, or appear to happen in the world of quantum. Whether in the world of quantum or otherwise the proof of theory is in repeatable experimentation I'm led to believe. Tegmark taking part in his quantum suicide game would go some way to prove his many worlds theory I guess.

[jeffreyH]

The problems begin when people try to add philosophy to quantum mechanics. They feel shocked that the results of experiments seem weird. They don't fit with their rational world view. That is not a shortcoming of quantum mechanics. It is a result of our limited perspective.

It isn't a problem that quantum mechanics is counter intuitive. It is the most interesting aspect of it.

[Harri (OP)]

I think I might fall into that category jeffrey. Yes most of the quantum world is weird and shocking but I only explore it in a positive way. And I too view it as exciting. Although I bring to the table 62 years of philosophy and learning e.t.c. ... if nothing else I have always been inquisitive, open minded to all possibilities and perhaps a little 'weird' to my friends and family in that respect. 'Entanglement' and 'superposition' may bring a 'get out of here' response from most people ... my response ... WOW!

On the subject of superposition ... do waves/particles in a superposition have mass? I ask because ... A wave or A particle with mass would have some affect on the actual surrounding space. And if these waves/particle were in a superposition wouldn't the effect on the surrounding space be greater? In my head I see a fish in a bath with the consequence of displacement and water disturbance. If there were many more fish in the bath I would expect to see more displacement and water displacement. Entering the bathroom and observing the one fish the water level would be lower than before I entered the room.

[Halc]

On the subject of superposition ... do waves/particles in a superposition have mass?

All particles have mass.  Things that move at light speed have relativistic mass, but not proper mass.  Waves are not really 'things', but rather disturbances in a medium, and any mass associated with them is best associated with the medium and not the disturbance.  Superposition makes no difference to any of this.  A cat in superposition of being dead and alive still masses one cat, else I could make an infinite energy device using the concept.

I ask because ... A wave or A particle with mass would have some affect on the actual surrounding space. And if these waves/particle were in a superposition wouldn't the effect on the surrounding space be greater?

No, the same.

In my head I see a fish in a bath with the consequence of displacement and water disturbance. If there were many more fish in the bath I would expect to see more displacement and water displacement.

Yes, but there is only the one fish, yes?  If it is in some kind of superposition, that's fine, but it cannot displace more water.

Entering the bathroom and observing the one fish the water level would be lower than before I entered the room.

You've envisioning two fish, rather than one in a superposition of states (like facing north and facing south).  The water has measured the direction the fish is facing, so the water is entangled with the fish (is in superposition along with the fish).  It takes an incredible amount of effort to not measure this and collapse the superposition state.  Not being in the room isn't anywhere near enough, but they have actually done it with a macroscopic object (one large enough to see without instruments).

[Colin2B]

.... if these waves/particle were in a superposition wouldn't the effect on the surrounding space be greater?

If the particle in superposition has an effect on the surrounding space this would in effect be a measurement and hence we could detect the state and the particle which would no longer be in superposition but in a defined state.
Note: a particle in superposition is not particles (plural) but particle (singular).

[set fair]

Perhaps you could give us an outline of the Quantum Suicide Game. I came across something that may be it or related to it. It goes like this. A physicist rigs up a device to randomly select numbers for the lottery in the belief that in nearly all the many worlds she will lose but in a few she will win. The winning numbers are fed into a device which will kill her (in her sleep) if it doesn't match her numbers. The outcome is that she will go to sleep and when she wakes up she cashes her winning ticket.

[Harri (OP)]

I can't post attachments in my post so I've cut and pasted this ...   The quantum suicide thought experiment was first posed by Max Tegmark in 1997, and it goes something like this: Imagine a gun is hooked up to a machine that measures the spin of a quantum particle every time the trigger is pulled. If the particle is measured as spinning clockwise, the gun will fire; if it's spinning counter-clockwise, it won't. A man points the gun at a sandbag and pulls the trigger 10 times. The gun goes off seemingly at random: "bang-click-bang-bang-bang-click-click-bang-click-click." Then, the man points the gun at his own head and attempts to pull the trigger 10 more times. What does he hear? "Click-click-click-click-click-click-click-click-click-click." He could keep on pulling the trigger for eternity, and the gun would never fire. How is that possible?

Now let's go back in time to the first moment he pointed the gun at his head. He pulls the trigger, and the gun fires. The man is dead. How can that happen when we already know the gun never fired? It's because every time he pulls the trigger, the universe splits into separate timelines: one where the gun fired, one where it didn't. When he was shooting the sandbag, he existed in the timelines created by that series of bangs and clicks. But when he aimed the gun at himself, the only timelines he could exist in were the ones where he survived — and thus, the ones where the gun didn't go off.

[Halc]

I can't post attachments in my post so I've cut and pasted this ...   The quantum suicide thought experiment was first posed by Max Tegmark in 1997, and it goes something like this: Imagine a gun is hooked up to a machine that measures the spin of a quantum particle every time the trigger is pulled. If the particle is measured as spinning clockwise, the gun will fire; if it's spinning counter-clockwise, it won't. A man points the gun at a sandbag and pulls the trigger 10 times. The gun goes off seemingly at random: "bang-click-bang-bang-bang-click-click-bang-click-click." Then, the man points the gun at his own head and attempts to pull the trigger 10 more times. What does he hear? "Click-click-click-click-click-click-click-click-click-click." He could keep on pulling the trigger for eternity, and the gun would never fire. How is that possible?

Yea, that's the original idea.  My complaint against it is that he is assuming an interpretation that doesn't give an identity (something that satisfies the law of identity) to a person, and yet he equates the identity of the person commencing this experiment with the person that survives it.  The one survivor (about a thousand to one odds) hears all the clicks and the other 10 Tegmarks are dead, and the only reason the losers don't remember hearing 'bang' is because the device removes their ability to remember that outcome.

Now let's go back in time to the first moment he pointed the gun at his head. He pulls the trigger, and the gun fires. The man is dead. How can that happen when we already know the gun never fired?

Nobody in the world with the body knows that the gun never fired. They've obviously measured otherwise.

It's because every time he pulls the trigger, the universe splits into separate timelines: one where the gun fired, one where it didn't. When he was shooting the sandbag, he existed in the timelines created by that series of bangs and clicks. But when he aimed the gun at himself, the only timelines he could exist in were the ones where he survived — and thus, the ones where the gun didn't go off.

Sounds like you got a handle on it.  Don't think it's something I'd like to try.