> ......... Yes, it seems all the empirical evidence is mounting
> against a truly cosmic-scale implementation of Tipler's design for
> infinite/eternal computation, but could his design be implemented on a
> smaller scale? In other words, just because the cosmos in toto won't
> collapse, couldn't a local region be structured for asymetrical collapse to
> achieve the same result?
Lawrence Schulman claims that it is possible to have opposite-running-time
regions and that ³some² degree of contact between them will not destroy the
arrows of time.
In the same way that electrons and positrons run in opposite time
directions, there are - Schulman suggests - galaxies with backward-running
time, following the timeline from Crunch to Bang.
At this instant they are, perhaps, very old and hence not very luminous,
although they are still exerting a gravitational pull.
I do not know whether, or not, "some" interaction between these
opposite-running-time regions, or galaxies, or universes, could ensure the
infinite computing power. Maybe.
A compromised arrow of time
L. S. Schulman
The second law of thermodynamics - the usual statement of the arrow of time
- has been called the most fundamental law of physics. It is thus difficult
to conceive that a single dynamical system could contain subsystems, in
significant mutual contact, possessing opposite thermodynamic arrows of
time. By examining cosmological justification for the usual arrow it is
found that a consistent way to establish such justification is by giving
symmetric boundary conditions at two (cosmologically remote) times and
seeking directional behavior in between. Once this has been demonstrated, it
is seen that entropy increase can be reversed and that the usual arrow is
less totalitarian than previously believed. In the same vein, other boundary
conditions, modeling shorter periods in the evolution of the cosmos, can be
found that allow the simultaneous existence of two thermodynamic arrows,
notwithstanding moderate interaction between the systems possessing those
arrows. Physical consequences of the existence and detection of
opposite-arrow regions are also considered.
Opposite Thermodynamic Arrows of Time
L. S. Schulman
A model in which two weakly coupled systems maintain opposite running
thermodynamic arrows of time is exhibited. Each experiences its own retarded
electromagnetic interaction and can be seen by the other. The possibility of
opposite-arrow systems at stellar distances is explored and a relation to
dark matter suggested.
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