[ExI] Public draft of my book 'Tales of the Turing Church

[Stuart LaForge]

John Clark wrote:

>  Copenhagen has many faults but I don't think FTL wave function collapse
> violates relativity because it can't be used to transmit a  signal faster
> than light.  

It's not the potential for FTL signals that is the problem. It is the
instantaneous nature of collapse. If you and I are space-like separated
and we are both studying the same entangled quantum system, then the first
one of us to observe our entangled particle instantly collapses the wave
function for both of us. But according to relativity, the concept of
"first" between two space-like separated events is meaningless. So which
one of us actually collapsed the wave function? Instantaneous wave
function collapse and general relativity are logically incompatible.

>
>> That was the part of Everett's interpretation that I disliked the most
>> until I realized that the math works out the same if universe doesn't
>> split because all the possible universes are all already out there 
>
> That is only from the viewpoint of somebody outside the multiverse
> looking in at it, and that viewpoint does not exist.

I am not sure I understand this objection. I can never directly observe
the fusion occurring in the heart of the sun, yet I can be confident it
occurs based on theory and the observation of the energy released.
Similarly I cannot observe the multiverse, but I can observe the quantum
states that result from statistically sampling from the multiverse.

>>  If all possible causal cells (Everett branches) exist on the same
>> infinite n-dimensional manifold, then the overall state of universe
>> itself does not change
>
> Does not change in what dimension? If the spacetime in the multiverse did
> not change in any direction the Multiverse could only be an eternal
> unbounded infinitely large homogeneous lattice, and anything that simple
> and dull could never have something as complex as life in it or anything
> interesting.  

If the multiverse contains all possible arrangements of matter and energy
in all possible space-times then the multiverse as a whole cannot change.
Similarly, there are infinite possible subsets of integers, and I can
sample the integers over time and get a different subset each time, so the
subsets can vary over time, but the infinite set of all integers does not
change.

> When speaking about the multiverse and Many Worlds the use of personal
> pronouns like "you" and "your" can easily become ambiguous.

True. Where the multiverse is concerned you are no longer an individual
but an entire category of individuals that share certain properties.
However all the instances of you throughout the multiverse should, in
theory, be entangled with one another. So there is still some
justification for all your instances being called you.

>
>
>>>   I don't see how  locality could be wrong. If things were non-local
>>> a change anywhere would instantly change everything everywhere and
>>> before you could understand anything you'd have to understand
>>> everything. We certainly don't know everything but we do know a few
>>> things and I don't see how we could if things were non-local.
>
>>  String theorists propose as many as 14 dimensions. All it takes is for
>> one of those extra dimensions to actually exist and opposite sides of
>> the observable universe could be an inch apart through that extra
>> dimension.
>
> But then it's hard to understand why classical physics can do such a good
> job at predicting the tides when it only takes into account the moon and
> the sun, it ignores all the movements of planets a billion light years
> away and assumes that things are local. And classical physics gets away
> with it and I don't see how it could if things were not local. 

Well most things in physics probably are local but for some reason quantum
information doesn't seem to be. Either that or everything that exists
exists solely to be observed by consciousness, and doesn't exist when not
being observed. And that sounds a lot like a simulation to me.

> Alan Guth's Inflation theory explains that very nicely, the distant parts
> of the universe we see with our largest telescopes are not causally
> connected now but at one time there were, and then the universe expanded
> much faster than light and that's why they are in thermal equilibrium
> now.

I have some serious misgivings of physics that supposedly worked once and
only once in the entire history of the universe solely for the purpose of
patching holes in our models. For example, superluminal inflation would
have super-cooled the universe requiring a "reheating" period which is
just kind of glossed over. How would the universe have reheated itself
after inflation. Where did the heat come from if the universe was all
there was and fusion which requires baryons hadn't started yet?

> But the fact is you chose to do X
> rather than Y because you prefer X. Why do you prefer X ? There are only
> 2 possibilities,  there was a reason for you preferring it in which case
> you are in the realm of cause and effect, or there was no cause for your
> preference in which case it was random. So it's always a cuckoo clock or
> a roulette wheel.

A choice is a decision and decisions are not mystical phenomenon. A
thermostat makes decisions, computers make decisions, and bacteria make
decisions. Choice is a real physical phenomenon.

I think you are conflating reason with cause. I can choose to save my
money to buy a car in the future. Such a choice has no cause because
classic causation presumably follows the arrow of time. Causes are in the
past and effects are in the future. Therefore my preference to save my
money has no past cause but it certainly has a reason and is certainly not
random or irrational. You could make a case for reverse causation, but I
have trouble envisioning a retrocausal cuckoo clock.
 

>>  Furthermore Conway published theorems regarding free will which
>> defined it as the ability to make choices that are not a function of >>
the past.

> That's an event without a cause, and that's the definition of random. 

Humans can make decisions based upon preferences for future states that do
not yet exist. Those decisions are events that are neither random nor
caused by most accepted notions of causation.

> The only definition of free will that I know of that isn't gibberish is
> the inability to always know for sure what you're going to do next until
> you actually do it, and I find that no more mysterious and profound than
> the fact that you don't know what the results of a calculation will be
> until you've finished the calculation.

I agree that there is nothing profound or mysterious about the ability to
make decisions.

>
>>  Whether Conway's definition of free will is correct or not is
>> debatable, but I can deliberately choose to say a non-sequitur or do
>> something unpredicatbly spontaneous.
>
> I agree, there is no law of logic that demands every event have a cause,
> randomness is possible. And there is another name for doing things for no
> reason, irrational.  

Not all reasons for doing things are causes since some reasons for doing
things are the effects of whatever it is that your are doing. And doing
something to bring about a desired effect is neither random or irrational.


> I sure don't see why that doesn't follow! Evolution can't see
> consciousness so it certainly could not have selected for it, and yet it
> produced me and I am conscious. So Evolution must have selected for
> something that it can see, like intelligence, and consciousness just rode
> in on its coattails.

Neither me nor evolution would be able to see the intelligence of John
Clark if he were implemented on a computer so slow that it took days to
process the image of a dangerous predator stalking him. Perhaps this means
intelligence is a relative and time-dependent phenomenon rather than being
some sort of all or nothing absolute.

> No, if Life is Turing complete, and it is, then it necessarily does mean
> it can emulate Windows or a Mac or the actions of John Clark. Of course
> to do all that the Turing Machine used would need to able to go into many
> many different states, but that's just a question of software, the
> hardware wouldn't change.

I think intelligence is more than just the sheer number of states a system
has but also how fast the system can change between those states. Which
might be why nobody uses the adjective intelligent to describe plants.

Stuart LaForge