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The Universe As Magic Roundabout
Posted on Saturday, January 20, 2007 (CST) by Thoth
 Ever feel like you've been there, done that, and that the life you're living seems strangely familiar? Maybe a psychic has told you that you were once a great king or queen, or, at the very least, their eunuch.
Perhaps a neurologist has told you that the déjà vu that you're experiencing is just a trick of the mind. But while these explanations may appeal to either the spiritually or scientifically inclined, physicist Peter Lynds argues that there may be a much grander account that explains the repetitiveness of life: a cyclic universe.
In this, the first part of two articles, we look at what Lynds considers to be both vital and overlooked cosmological questions regarding the origin and mechanics of a cyclic universe.
Of course,
referring to past lives and déjà vu is being a tad flippant in regard
to Lynds' new paper on a cyclic universe, "On A Finite Universe With No
Beginning Or End," as these areas, he explains, are really the
philosophical fallout - determinism, free will, and life after death -
of his new theory. In a nutshell, the model of the universe that Lynds
is proposing, similar to others before him, is that the universe is in
fact closed and subject to an infinite cycle of big bangs and big
crunches. However, the difference between Lynds' theory and those that
have gone before it is that in Lynds' model the big bang is no more the
beginning of the universe than the big crunch is its end. Lynds
explains, as suggested by paper's title, that while the universe is
finite, there is no arrow of time; there is no past or present, and
that in neither a big crunch nor big bang is a singularity ever reached.
Lynds' latest cosmological
rumination follows a previous paper he wrote on time, and it's sure to
spark up just as much controversy. In his earlier paper, Lynds argued,
in effect, that time doesn't really exist. That is to say, there are no
discrete measurements of time that can be observed in nature, and that
our concepts of it are dependent upon the relative motions of mass and
energy. His latest effort continues along these lines, arguing that our
linear concept of time - firmly established with the introduction of
the Christian calendar - has, effectively, blinkered us from the
possibility of a cyclic universe. At this point, Lynds' critics are
sure to be thinking that he's up to his old tricks again, but he
introduces some very solid arguments, employing no less than the second
law of thermodynamics to support his claims.
Lynds' paper opens with a
paradox raised by the German philosopher Immanuel Kant, who pondered
two competing, yet similarly contradictory theories of the universe.
Kant was faced with either a universe that stretched back infinitely
through time, where there would be an infinite period of time before
any event (a procrastinator's dream), or, of a universe that did have a
beginning, but which has an equally dissatisfying outcome, as it begs
the question of what came before the "beginning," ad infinitum. Lynds
explains that the genius of Kant's paradox is yet to be properly
realized, as through proper investigation it should tell us something
about our most fundamental assumptions regarding time, cause and
cosmology. To this end, Lynds' model attempts to address the rather
curly issue of where the universe came from, and the problems
associated with both a finite and infinite universe through his model
of a cyclic universe.
Casting an eye over
previous attempts at explaining the mechanics of a cyclic universe,
Lynds turned to Stephen Hawking. Lynds relates how Hawking once
discussed how the second law of thermodynamics might affect the future
of a contracting universe (towards a big crunch). The second law of
thermodynamics is one of those rock-solid physical laws, the big gun
that a scientist may use to quell the pseudo-scientific flights of
fancy held by the reality challenged. As Lynds explains, the law states
that "heat can never pass spontaneously, or of itself, from a hot to
hotter body. Hot flows to cold." This means two things: that the
one-way direction of energy transference involved in natural processes
is irreversible, and that the entropy of an isolated system will
increase with time.
Initially, Hawking
concluded that if the universe did begin to contract then the
thermodynamic "arrow of time," as it is often called (erroneously,
according to Lynds), would also reverse. "Everything would go into the
reverse of the way we experience things today: light would travel back
to the stars, and broken eggs on the floor would miraculously put
themselves back together again," says Lynds. Philip K. Dick, of Blade
Runner fame, once wrote about a similar situation in his novel
Counter-Clock World, where many of the consequences of time reversal -
such as dead relatives and feces taking up, er, previously held
positions in your life (to be honest, I'm not sure which would be
worse) - seem quite unpalatable. Hawking stated that such a reversal
would mean that hot would flow to hotter, and that entropy would need
to decrease because, as Lynds explains, "the universe would have to
return to a symmetrical state of low entropy and high order at a big
crunch." Thankfully, the unfolding of such an unsavory scenario is
unlikely due to a number of impossible situations that would arise, not
least of which being that it would require that entropy decrease and
thus break the second law of thermodynamics. As Lynds points out,
Hawking called this "his greatest mistake."
In his model, Lynds manages
to account for, or perhaps dodge, the irreversible, asymmetric nature
of the second law of thermodynamics in a rather novel way. Lynds
reasons that if all other physical laws other than the second law are
reversible, or symmetric, then when the universe is faced with a
situation where entropy may have to decrease instead of increase; "the
order of events would simply reverse so that events took place in the
direction in which entropy was still increasing," says Lynds. "In
relation to the big crunch, this would mean that at the point where the
second law would have been breached, any future events in this
direction (where entropy would be decreasing) would reverse."
These second law
restrictions would also mean that instead of a big crunch singularity
occurring, events would instantly proceed from where this singularity
would have taken place had events not reversed. Lynds explains that
following from this: "The universe would expand from where the big
crunch singularity would have been had events not reversed (i.e. the
big crunch reversed), and with events going in this direction, entropy
would still be increasing, no singularity would be encountered, and no
laws of physics would be contravened. They would all still hold."
Copyright: Science a Go Go
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