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From: Higgo James <james.higgo.domain.name.hidden>

Date: Mon, 16 Nov 1998 09:48:03 -0000

Give me your feedback, Guys!

November 1998

Does the 'many-worlds' interpretation of quantum mechanics

imply immortality?

James Higgo

18 Harcourt Terrace

London SW10 9JR

e-mail james.higgo.domain.name.hidden

Abstract

The Everett 'Many Worlds Interpretation' of quantum physics

postulates that that all systems evolve according to the Schrödinger

equation, whereas the more conventional Copenhagen Interpretation says that

this is true until the moment of observation, at which point the equation

'collapses'. The proposed paper examines some philosophical questions

arising from the MWI interpretation. In particular, it synthesises the

Tegmark (1997) 'quantum suicide' experiment with the Stapp (1998) analysis

of the quantum effects on calcium ions in neural synapses, to develop a

'Quantum Theory of Immortality' (QTI).

The 'Many-Worlds' Interpretation of Quantum Physics

First, a disclaimer for those new to the subject: Niels Bohr, the founder of

modern quantum theory said, "Anyone who is not shocked by quantum theory has

not understood it". And he didn't understand the Many-Worlds Interpretation

(MWI). The quantum mechanics (QM) presented here is quite mainstream, even

though it still seems crazy to physicists, who have no choice but to accept

it. The major assumption I have made is to adopt Everett's (1957) MWI,

which is just one of half a dozen competing interpretations of QM. According

to various polls, MWI and the original 1927 'Copenhagen Interpretation' now

have a similar share of the votes among physicists, but many of the 'big

names' (Hawking, Feynman, Deutsch, Weinberg) are said to () have subscribed

to the MWI.

The weirdness of quantum physics can be seen in the famous parallel-slit

experiment. This shows that individual photons seem to split into two

particles which can nevertheless interfere with each other as if they were

waves. The 'Copenhagen Interpretation' of the phenomena and the equations

which describe them, agreed at the 1927 Solvay conference, essentially says

that the 'wave packet' somehow associated with a particle 'collapses' when

it is observed - this necessitates a relationship between the observer's

consciousness and the particle. The MWI, on the other hand, holds that the

equations used to predict quantum mechanical events continue to hold after

observation - it is just that all things happen simultaneously, but due to

'decoherence' we do not actually see, for example, a radioactive source both

decay and not decay. For an explanation of how this implies parallel

universes, see Vaidman (1996).

There is one way of proving that the MWI is true and the Copenhagen and

other interpretations are wrong. Unfortunately, the experimenter can only

prove it to himself, and never persuade anyone else of its validity.

The Tegmark 'Quantum Suicide' experiment

Tegmark (1997) describes the 'Quantum Suicide Experiment' as follows (I have

simplified the text and removed the mathematical proofs):

The apparatus is a "quantum gun" which each time its trigger is

pulled measures the z-spin of a particle [particles can be spin up or spin

down, seemingly at random]. It is connected to a machine gun that fires a

single bullet if the result is "down" and merely makes an audible click if

the result is "up".... The experimenter first places a sand bag in front of

the gun and tells her assistant to pull the trigger ten times. All [QM

interpretations] predict that she will hear a seemingly random sequence of

shots and duds such as

"bang-click-bang-bang-bang-click-click-bang-click-click". She now instructs

her assistant to pull the trigger ten more times and places her head in

front of the barrel. This time the "shut-up-and calculate" [non-MWI

interpretations of QM] have no meaning for an observer in the dead state...

and the [interpretations] will differ in their predictions. In

interpretations where there is an explicit non-unitary collapse, she will be

either dead or alive after the first trigger event, so she should expect to

perceive perhaps a click or two (if she is moderately lucky), then "game

over", nothing at all. In the MWI, on the other hand, the ... prediction is

that [the experimenter] will hear "click" with 100% certainty. When her

assistant has completed this unenviable assignment, she will have heard ten

clicks, and concluded that the collapse interpretations of quantum mechanics

[all but the MWI] are ruled out to a confidence level of 1-0.5n ~ 99.9%. If

she wants to rule them out "ten sigma", she need merely increase n by

continuing the experiment a while longer. Occasionally, to verify that the

apparatus is working, she can move her head away from the gun and suddenly

hear it going off intermittently. Note, however, that [almost all

instances] will have her assistant perceiving that he has killed his boss.

What this means is that, in most universes, there is one less experimenter,

but the experimenter herself does not experience death.

The QTI is formed by reformulating the 'Quantum Suicide' experiment so that

the movement of a calcium ion in a brain is used as a proxy for the

spin-watching 'quantum gun', following the work of Stapp.

Stapp's work on 'Quantum Theories of the Mind'

Stapp does not accept the MWI, but prefers the Copenhagen Interpretation for

reasons - essentially matter of philosophical preference - given in Stapp

(April, 1996) and (July 21, 1998). This does not affect the useful analysis

he puts forward concerning the quantum effects inside synapses.

Stapp shows that quantum effects are indeed important in the way the brain

operates. In fact, they must have a dramatic effect on the function if the

brain - perhaps allowing it to function as a 'quantum computer' and take

advantage of search algorithms, perhaps similar to that proposed by Grover

(1997)

Stapp's (April, 1996) evidence that quantum effects must be present in the

brain is as follows:

a) A calcium ion entering a bouton through a microchannel of

diameter x must, by Heisenberg's indeterminacy principle, have a momentum

spread of hbar/x, and hence a velocity spread of (hbar/x)/m, and hence a

spatial spread oin time t, if the particle were freely moving, of

t(hbar/x)/m. Taking t to be 200 microseconds, the typical time for the ion

to diffuse from the microchannel opening to a triggering site for the

release of a vesicle of neurotransmitter, and taking x to be one nanometer,

and including a factor of 10-5 for diffusion slowing, one finds the diameter

of the wave function to be about 40 times 10-8 centimeters, which is

comparable to the size of the calcium ion itself.

In other words, it is quite feasible that in some universes a

neurotransmitter will activate its target, whereas in others it will not,

simply due to the 'Heisenberg uncertainty principle'.

This is important when trying to understand how the brain can act as a

'quantum computer', and very interesting when we take these ideas in

conjunction with Tegmark's experiment.

Integrating Tegmark and Stapp

Consider a calcium ion which has a 50% probability, according to

Schrödinger's equations, of activating its target receptor. Imagine that

that receptor will make the difference between two possible states of mind:

one corresponding with a motorcyclist's decision to overtake a car on a

dangerous road, and the other corresponding with the opposite decision.

Assume that the overtaking manoeuvre would be fatal.

The motorcyclist is the experimenter in Tegmark's quantum suicide. According

to the MWI prediction, the cyclist will perceive that he has made the

decision corresponding to the staying-alive outcome with 100% certainty. Of

course, onlookers in 50% of universes will see a messy accident.

The Quantum Theory of Immortality developed here avers that all

life-or-death decisions correspond with the same quantum mechanical

equations. In all life-or-death decisions, the 'experimenter' finds that he

has chosen life.

Further implications

Deutsch (1997) argues that it follows from MWI that anything possible exists

- somewhere in the 'multiverse'. If this is true, we can say that there are

many universes (but a very tiny proportion of the multiverse) where you,

dear reader, are a billion years old.

Could it follow that you, the experimenter's consciousness, will inevitably

'end up' in one of those universes? If so, we are immortal - from our own

point of view.

Problems with Quantum Theory of Immortality

The QTI rests on some contentious premises: Deutsch's development of the

Everett 'many-worlds' hypothesis; the Tegmark 'quantum suicide' experiment,

Stapp's work on quantum effects on the brain and, most tentatively, the idea

that the specific case of the 'quantum gun' can be generalised into any

life-or-death scenario.

Bibliography

1. Deutsch, David, The Fabric of Reality, (Penguin Books, 1997)

2. DeWitt, B. S. and N. Graham, eds., The Many Worlds Interpretation of

Quantum Mechanics, (Princeton University Press, Princeton, 1973).

3. Grover, L. K, 'Quantum mechanics helps in searching for a needle in

a haystack', Phys. Rev. Lett 79, 325-328 (1997)

4. Stapp, Henry P, Mind, Matter, and Quantum Mechanics

(Springer-Verlag, Berlin, New York, 1993)

5. Stapp, Henry P., On Quantum Theories of the Mind, (Lawrence Berkeley

National Laboratory, May 29, 1997)

6. Stapp, Henry P., Quantum Ontology and Mind-Matter Synthesis

(Lawrence Berkeley National Laboratory, July 21 1998)

7. Stapp, Henry P., Science of Consciousness and the Hard Problem

(Proceedings of the Conference Toward a Science of Consciousness, University

of Arizona, April 8-13,1996)

8. Steane, Andrew, Quantum Computing (unpublished, July 1997)

Tegmark, Max, 'The Interpretation of Quantum Mechanics: Many Worlds or Many

Worlds', preprint September 15, 1997

Received on Mon Nov 16 1998 - 01:52:10 PST

Date: Mon, 16 Nov 1998 09:48:03 -0000

Give me your feedback, Guys!

November 1998

Does the 'many-worlds' interpretation of quantum mechanics

imply immortality?

James Higgo

18 Harcourt Terrace

London SW10 9JR

e-mail james.higgo.domain.name.hidden

Abstract

The Everett 'Many Worlds Interpretation' of quantum physics

postulates that that all systems evolve according to the Schrödinger

equation, whereas the more conventional Copenhagen Interpretation says that

this is true until the moment of observation, at which point the equation

'collapses'. The proposed paper examines some philosophical questions

arising from the MWI interpretation. In particular, it synthesises the

Tegmark (1997) 'quantum suicide' experiment with the Stapp (1998) analysis

of the quantum effects on calcium ions in neural synapses, to develop a

'Quantum Theory of Immortality' (QTI).

The 'Many-Worlds' Interpretation of Quantum Physics

First, a disclaimer for those new to the subject: Niels Bohr, the founder of

modern quantum theory said, "Anyone who is not shocked by quantum theory has

not understood it". And he didn't understand the Many-Worlds Interpretation

(MWI). The quantum mechanics (QM) presented here is quite mainstream, even

though it still seems crazy to physicists, who have no choice but to accept

it. The major assumption I have made is to adopt Everett's (1957) MWI,

which is just one of half a dozen competing interpretations of QM. According

to various polls, MWI and the original 1927 'Copenhagen Interpretation' now

have a similar share of the votes among physicists, but many of the 'big

names' (Hawking, Feynman, Deutsch, Weinberg) are said to () have subscribed

to the MWI.

The weirdness of quantum physics can be seen in the famous parallel-slit

experiment. This shows that individual photons seem to split into two

particles which can nevertheless interfere with each other as if they were

waves. The 'Copenhagen Interpretation' of the phenomena and the equations

which describe them, agreed at the 1927 Solvay conference, essentially says

that the 'wave packet' somehow associated with a particle 'collapses' when

it is observed - this necessitates a relationship between the observer's

consciousness and the particle. The MWI, on the other hand, holds that the

equations used to predict quantum mechanical events continue to hold after

observation - it is just that all things happen simultaneously, but due to

'decoherence' we do not actually see, for example, a radioactive source both

decay and not decay. For an explanation of how this implies parallel

universes, see Vaidman (1996).

There is one way of proving that the MWI is true and the Copenhagen and

other interpretations are wrong. Unfortunately, the experimenter can only

prove it to himself, and never persuade anyone else of its validity.

The Tegmark 'Quantum Suicide' experiment

Tegmark (1997) describes the 'Quantum Suicide Experiment' as follows (I have

simplified the text and removed the mathematical proofs):

The apparatus is a "quantum gun" which each time its trigger is

pulled measures the z-spin of a particle [particles can be spin up or spin

down, seemingly at random]. It is connected to a machine gun that fires a

single bullet if the result is "down" and merely makes an audible click if

the result is "up".... The experimenter first places a sand bag in front of

the gun and tells her assistant to pull the trigger ten times. All [QM

interpretations] predict that she will hear a seemingly random sequence of

shots and duds such as

"bang-click-bang-bang-bang-click-click-bang-click-click". She now instructs

her assistant to pull the trigger ten more times and places her head in

front of the barrel. This time the "shut-up-and calculate" [non-MWI

interpretations of QM] have no meaning for an observer in the dead state...

and the [interpretations] will differ in their predictions. In

interpretations where there is an explicit non-unitary collapse, she will be

either dead or alive after the first trigger event, so she should expect to

perceive perhaps a click or two (if she is moderately lucky), then "game

over", nothing at all. In the MWI, on the other hand, the ... prediction is

that [the experimenter] will hear "click" with 100% certainty. When her

assistant has completed this unenviable assignment, she will have heard ten

clicks, and concluded that the collapse interpretations of quantum mechanics

[all but the MWI] are ruled out to a confidence level of 1-0.5n ~ 99.9%. If

she wants to rule them out "ten sigma", she need merely increase n by

continuing the experiment a while longer. Occasionally, to verify that the

apparatus is working, she can move her head away from the gun and suddenly

hear it going off intermittently. Note, however, that [almost all

instances] will have her assistant perceiving that he has killed his boss.

What this means is that, in most universes, there is one less experimenter,

but the experimenter herself does not experience death.

The QTI is formed by reformulating the 'Quantum Suicide' experiment so that

the movement of a calcium ion in a brain is used as a proxy for the

spin-watching 'quantum gun', following the work of Stapp.

Stapp's work on 'Quantum Theories of the Mind'

Stapp does not accept the MWI, but prefers the Copenhagen Interpretation for

reasons - essentially matter of philosophical preference - given in Stapp

(April, 1996) and (July 21, 1998). This does not affect the useful analysis

he puts forward concerning the quantum effects inside synapses.

Stapp shows that quantum effects are indeed important in the way the brain

operates. In fact, they must have a dramatic effect on the function if the

brain - perhaps allowing it to function as a 'quantum computer' and take

advantage of search algorithms, perhaps similar to that proposed by Grover

(1997)

Stapp's (April, 1996) evidence that quantum effects must be present in the

brain is as follows:

a) A calcium ion entering a bouton through a microchannel of

diameter x must, by Heisenberg's indeterminacy principle, have a momentum

spread of hbar/x, and hence a velocity spread of (hbar/x)/m, and hence a

spatial spread oin time t, if the particle were freely moving, of

t(hbar/x)/m. Taking t to be 200 microseconds, the typical time for the ion

to diffuse from the microchannel opening to a triggering site for the

release of a vesicle of neurotransmitter, and taking x to be one nanometer,

and including a factor of 10-5 for diffusion slowing, one finds the diameter

of the wave function to be about 40 times 10-8 centimeters, which is

comparable to the size of the calcium ion itself.

In other words, it is quite feasible that in some universes a

neurotransmitter will activate its target, whereas in others it will not,

simply due to the 'Heisenberg uncertainty principle'.

This is important when trying to understand how the brain can act as a

'quantum computer', and very interesting when we take these ideas in

conjunction with Tegmark's experiment.

Integrating Tegmark and Stapp

Consider a calcium ion which has a 50% probability, according to

Schrödinger's equations, of activating its target receptor. Imagine that

that receptor will make the difference between two possible states of mind:

one corresponding with a motorcyclist's decision to overtake a car on a

dangerous road, and the other corresponding with the opposite decision.

Assume that the overtaking manoeuvre would be fatal.

The motorcyclist is the experimenter in Tegmark's quantum suicide. According

to the MWI prediction, the cyclist will perceive that he has made the

decision corresponding to the staying-alive outcome with 100% certainty. Of

course, onlookers in 50% of universes will see a messy accident.

The Quantum Theory of Immortality developed here avers that all

life-or-death decisions correspond with the same quantum mechanical

equations. In all life-or-death decisions, the 'experimenter' finds that he

has chosen life.

Further implications

Deutsch (1997) argues that it follows from MWI that anything possible exists

- somewhere in the 'multiverse'. If this is true, we can say that there are

many universes (but a very tiny proportion of the multiverse) where you,

dear reader, are a billion years old.

Could it follow that you, the experimenter's consciousness, will inevitably

'end up' in one of those universes? If so, we are immortal - from our own

point of view.

Problems with Quantum Theory of Immortality

The QTI rests on some contentious premises: Deutsch's development of the

Everett 'many-worlds' hypothesis; the Tegmark 'quantum suicide' experiment,

Stapp's work on quantum effects on the brain and, most tentatively, the idea

that the specific case of the 'quantum gun' can be generalised into any

life-or-death scenario.

Bibliography

1. Deutsch, David, The Fabric of Reality, (Penguin Books, 1997)

2. DeWitt, B. S. and N. Graham, eds., The Many Worlds Interpretation of

Quantum Mechanics, (Princeton University Press, Princeton, 1973).

3. Grover, L. K, 'Quantum mechanics helps in searching for a needle in

a haystack', Phys. Rev. Lett 79, 325-328 (1997)

4. Stapp, Henry P, Mind, Matter, and Quantum Mechanics

(Springer-Verlag, Berlin, New York, 1993)

5. Stapp, Henry P., On Quantum Theories of the Mind, (Lawrence Berkeley

National Laboratory, May 29, 1997)

6. Stapp, Henry P., Quantum Ontology and Mind-Matter Synthesis

(Lawrence Berkeley National Laboratory, July 21 1998)

7. Stapp, Henry P., Science of Consciousness and the Hard Problem

(Proceedings of the Conference Toward a Science of Consciousness, University

of Arizona, April 8-13,1996)

8. Steane, Andrew, Quantum Computing (unpublished, July 1997)

Tegmark, Max, 'The Interpretation of Quantum Mechanics: Many Worlds or Many

Worlds', preprint September 15, 1997

Received on Mon Nov 16 1998 - 01:52:10 PST

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