Re: Omega Point theory and time quanta

2004-08-01 Thread Hal Finney
Stathis Papaioannou writes:
 There has been some discussion in recent posts about Tipler's Omega Point
 theory, which postulates that an infinite amount of subjective time can
 be squeezed into the last few moments of a collapsing universe. This
 is straightforward mathematically using infinite series, but if time
 is quantised, it would not work in reality; and it seems to be widely
 accepted that time is indeed quantised. Is there a way around this
 difficulty?

At 
http://www.sciam.com/askexpert_question.cfm?articleID=000A03B0-6000-1C71-9EB7809EC588F2D7
John Baez, a widely respected physicist, responds to the question,
is time quantized:

The brief answer to this question is, 'Nobody knows.' Certainly there
is no experimental evidence in favor of such a minimal unit. On the
other hand, there is no evidence against it, except that we have not yet
found it. There are no well-worked-out physics theories incorporating
a fundamental unit of time, and there are substantial obstacles to
doing so in a way that is compatible with the principles of General
Relativity. Recent work on a theory of quantum gravity in which gravity is
represented using loops in space suggests that there might be a way to do
something roughly along these lines--not involving a minimum unit of time
but rather a minimum amount of area for any two-dimensional surface, a
minimum volume for any three-dimensional region in space and perhaps also
a minimum 'hypervolume' for any four-dimensional region of space-time.

So I think it is an oversimplification to say that it is widely accepted
that time is quantized.  It is pretty clear that something strange
must happen as we go to smaller and smaller time and distance scales,
but nobody knows what.

Tipler's Omega Point theory is basically a theory of general relativity
and I don't think it incorporates quantum mechanics.  So it has to
be viewed as extremely speculative on that basis, although the same
thing might be said of the Big Bang, or of discussion of black hole
singularities, both of which involve infinities much like the Omega
Point theory does.

I'll tell you something else about the OP that most people don't know.
Many people may think of the universal collapse as providing an energy
source and/or effective time speedup which leads to this prediction
that an infinity of calculating can be done.  But this is not the case.
With overwhelming probability, a natural Big Crunch will not allow
for infinite calculations, rather only a finite amount of computation
is possible.

The only way to get an infinite amount of calculation is for the collapse
to take a very special and peculiar form, in which the universe oscillates
unstably from one extreme shape to another.  Instead of collapsing as
a nice little ball getting smaller and smaller, the universe has to
stretch in first one direction, then another, ever more extensively.

Such wild gyrations will not occur naturally, yet they are the only way
for infinite calculations to occur.  Only this will create the ever more
extreme temperature variations that can drive ever-faster calculations.

Tipler's idea is that life itself will take over control of the
universe's collapse.  Just as we may some day control the weather by
predicting its course with extreme accuracy and modifying inputs to
make it do what we want, so, Tipler theorizes, life could control the
very shape of the universal collapse by measuring it, making short
and long term predictions, and then making small modifications to the
energy and matter under life's control in order to shape the path.
Since the universal collapse is a chaotic system, as is the weather,
it might theoretically be possible.

Life's task will become ever more difficult as each oscillation of the
collapse occurs.  With each gyration, life must move more quickly and
accurately to keep the universe on its path.  A single slip-up anywhere
along the line and the potential for infinite calculation is lost.
And meanwhile the temperature is rising exponentially, threatening the
physical stability of whatever substrate of mass and energy life has
adopted to provide for continuity of existence.

Oh, and I forgot to mention that life at one side of the universe can't
communicate with life at the other side.  Infinite computation may be
possible but not infinite communication.  The photons won't get there
before the collapse occurs.  So all of this delicate balancing act must be
accomplished without any global communication, each part of the universe
must act on faith that every other part is going to perform exactly those
steps required to make the whole thing come together and work perfectly.
All this is without any pre-arrangment beyond what we can accomplish in
this era.  We better get our acts together before we head out colonizing.

Given these immense challenges, which increase in difficulty
and complexity literally without limit, improbability piled upon
impossibility, we can throw in the still-unknown 

Re: Omega Point theory and time quanta

2004-08-01 Thread scerir
From: Stathis Papaioannou 

 ...an infinite amount of subjective time can be squeezed 
 into the last few moments of a collapsing universe 

This reminds me of a strange story
I've learned long time ago.
A dynamical system which passes
through a succession of states, 
at constant time intervals, is
a clock. Clocks measure times,
and, coupled with other systems,
can also measure the duration 
of a physical process. Clocks can also
be used to control the duration
of a process, or the evolution of a 
physical system. In this case if a clock 
has a good time resolution, there is
some energy exchange between the
clock and the controlled process,
that is the evolution of the physical 
system under control. Both the evolution
of the physical system and the clock
are then perturbed, because when you 
include the clock mechanism in the Hamiltonian 
describing the quantum system to be observed, 
or to be controlled, you get this perturbation. 
If then a clock is too precise, a sort of 
quantum Zeno effect occurs - the evolution 
of the physical system under control may be 
even halted.



Re: Omega Point theory and time quanta

2004-08-01 Thread Stathis Papaioannou
I thought that quantum theory (in all its flavours and interpretations) 
*does* imply that reality isdigital. For example, if light is quantised, 
then the light reflected from a real object will produce a pixelated image, 
albeit far more finely grained than the image on any computer screen. The 
Bekenstein Bound sets an upper limit to the amount of information that can 
be contained in a given volume, or a lower limit to how finely grained an 
object or its representation can be. Everything is digital; analogue is an 
illusion.

Stathis Papaioannou
From: Norman Samish [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Omega Point theory and time quanta
Date: Sat, 31 Jul 2004 22:22:01 -0700
Perhaps mathematics, which is digital, is incapable of precise simulation 
of
reality, which is not digital.

Norman Samish
- Original Message -
From: Stathis Papaioannou [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Saturday, July 31, 2004 9:36 PM
Subject: Omega Point theory and time quanta
There has been some discussion in recent posts about Tipler's Omega Point
theory, which postulates that an infinite amount of subjective time can be
squeezed into the last few moments of a collapsing universe. This is
straightforward mathematically using infinite series, but if time is
quantised, it would not work in reality; and it seems to be widely accepted
that time is indeed quantised. Is there a way around this difficulty?
Stathis Papaioannou

_
Play Love Hunt to win a $9000 holiday and find love!  
http://mobilecentral.ninemsn.com.au/mclovehunt/lovehunt.aspx



Re: Omega Point theory and time quanta

2004-08-01 Thread Stathis Papaioannou
Danny Mayes writes:
***
This is my understanding as well.  Also, in regards to Hal's comments about 
how unlikely the OP theory is, or how our universe does not appear likely to 
collapse, even accepting these points if the OP computer is physically 
possible it must occur under the MWI (somewhere in the multiverse), correct?
***

Yes, this is true, and I believe Tipler threw it in as an afterthought in 
his book. The question arises, however, why would you bother with such an 
elaborate mechanism for immortality as the OP theory if the MWI of QM is 
correct? The MWI ensures immortality through an infinite number of possible 
scenarios which collectively must be far more likely than Omega Point.

***
I'm sure everyone is familiar with the ancient philosophical argument that 
time and space must be quantized, because if they were not you could never 
get to a determined point in space or time given that the distance left to 
travel could be infinitely divided in two...
***

Actually, I thing that this argument (Zeno) came about because the ancient 
Greeks did not have any concept of an infinite series which converges to a 
finite value. There is a related argument, however: if reality is analogue, 
then any physical parameter would require an infinite number of 
non-repeating decimal places to describe it exactly. This would mean that 
what appears to be a finite system, such as an analogue voltmeter measuring 
a voltage, actually contains an infinite amount of information, which is 
absurd. Therefore, physical reality must be digital rather than analogue at 
the finest level.

I am not sure where I first heard the above argument, and I am not sure 
about the absurdity of an infinite amount of information being contained in 
finite system.

Stathis Papaioannou
_
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---BeginMessage---




This is my understanding as well. Also, in regards to Hal's comments
about how unlikely the OP theory is, or how our universe does not
appear likely to collapse, even accepting these points if the OP
computer is physically possible it must occur under the MWI (somewhere
in the multiverse), correct?

I'm sure everyone is familiar with the ancient philosophical argument
that time and space must be quantized, because if they were not you
could never get to a determined point in space or time given that the
distance left to travel could be infinitely divided in two...

Stathis Papaioannou wrote:
I thought that
quantum theory (in all its flavours and interpretations) *does* imply
that reality is"digital". For example, if light is quantised, then the
light reflected from a real object will produce a pixelated image,
albeit far more finely grained than the image on any computer screen.
The Bekenstein Bound sets an upper limit to the amount of information
that can be contained in a given volume, or a lower limit to how finely
grained an object or its representation can be. Everything is digital;
analogue is an illusion.
  
  
Stathis Papaioannou
  
  
  From: "Norman Samish"
[EMAIL PROTECTED]

To: [EMAIL PROTECTED]
    
Subject: Re: Omega Point theory and time quanta

Date: Sat, 31 Jul 2004 22:22:01 -0700


Perhaps mathematics, which is digital, is incapable of precise
simulation of

reality, which is not digital.


Norman Samish


- Original Message -

From: "Stathis Papaioannou" [EMAIL PROTECTED]

To: [EMAIL PROTECTED]

Sent: Saturday, July 31, 2004 9:36 PM
    
Subject: Omega Point theory and time quanta



There has been some discussion in recent posts about Tipler's Omega
Point

theory, which postulates that an infinite amount of subjective time can
be

squeezed into the last few moments of a collapsing universe. This is

straightforward mathematically using infinite series, but if time is

quantised, it would not work in reality; and it seems to be widely
accepted

that time is indeed quantised. Is there a way around this difficulty?


Stathis Papaioannou



  
  
_
  
Play Love Hunt to win a $9000 holiday and find love!
http://mobilecentral.ninemsn.com.au/mclovehunt/lovehunt.aspx
  
  
  
  





---End Message---


Omega Point theory and time quanta

2004-07-31 Thread Stathis Papaioannou
There has been some discussion in recent posts about Tipler's Omega Point 
theory, which postulates
that an infinite amount of subjective time can be squeezed into the last few 
moments of a collapsing
universe. This is straightforward mathematically using infinite series, but 
if time is quantised, it
would not work in reality; and it seems to be widely accepted that time is 
indeed quantised. Is there
a way around this difficulty?

Stathis Papaioannou
_
Play Love Hunt to win a $9000 holiday and find love!  
http://mobilecentral.ninemsn.com.au/mclovehunt/lovehunt.aspx



Re: Omega Point theory and time quanta

2004-07-31 Thread Norman Samish
Perhaps mathematics, which is digital, is incapable of precise simulation of
reality, which is not digital.

Norman Samish

- Original Message - 
From: Stathis Papaioannou [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Saturday, July 31, 2004 9:36 PM
Subject: Omega Point theory and time quanta


There has been some discussion in recent posts about Tipler's Omega Point
theory, which postulates that an infinite amount of subjective time can be
squeezed into the last few moments of a collapsing universe. This is
straightforward mathematically using infinite series, but if time is
quantised, it would not work in reality; and it seems to be widely accepted
that time is indeed quantised. Is there a way around this difficulty?

Stathis Papaioannou