OUTRAGEOUS FORTUNE

Discussion on technology and how it could be used to assist spiritual development and NOT enslave us. This includes technology that will help us live in harmony with Nature (e.g.: "Lifter" technologies that could replace the petrol driven engine). Also, discussion of past and current scientific thought so that gems are not buried in the sands of time, and spiritual progress through science is achieved.

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bomohwkl
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OUTRAGEOUS FORTUNE

Post: # 9657Post bomohwkl »

A growing number of cosmologists and string theorists suspect the form of our Universe
is little more than a coincidence. Are these harmless thought experiments, or a challenge
to science itself? Geoff Brumfiel investigates.

Why are we here? It’s a question
that has troubled philosophers,
theologians and those who’ve
had one drink too many. But
theoretical physicists have a more essentialist
way of asking the question: why is there anything
here at all?
For two decades now, theorists in the thinkbig
field of cosmology have been stymied by a
mathematical quirk in their equations. If the
number controlling the growth of the Universe
since the Big Bang is just slightly too
high, the Universe expands so rapidly that protons
and neutrons never come close enough to
bond into atoms. If it is just ever-so-slightly
too small, it never expands enough, and everything
remains too hot for even a single nucleus
to form. Similar problems afflict the observed
masses of elementary particles and the
strengths of fundamental forces.
In other words, if you believe the equations
of the world’s leading cosmologists, the probability
that the Universe would turn out this
way by chance are infinitesimal — one in a
very large number. “It’s like you’re throwing
darts, and the bullseye is just one part in 10120
of the dart board,” says Leonard Susskind, a
string theorist based at Stanford University in
California. “It’s just stupid.”
One in a zillion
Physicists have historically approached this
predicament with the attitude that it’s not just
dumb luck. In their view, there must be something
underlying and yet-to-be-discovered
setting the value of these variables. “The idea is
that we have got to work harder because some
principle is missing,” says David Gross, a
Nobel-prizewinning theorist and director of
the Kavli Institute for Theoretical Physics in
Santa Barbara, California.
But things have changed in the past few
years, says astronomer Bernard Carr of Queen
Mary, University of London, UK. String theorists
and cosmologists are increasingly turning
to dumb luck as an explanation. If their ideas
stand up, it would mean the constants of nature
are meaningless. “In the past, many people
were almost violently opposed to that idea
because it wasn’t seen as proper science,” Carr
says. “But there’s been a change of attitude.”
Much of that change stems from work
showing that our Universe may not be unique.
Since the early 1980s, some cosmologists have
argued that multiple universes could have
formed during a period of cosmic inflation
that preceded the Big Bang. More recently,
string theorists have calculated that there
could be 10500 universes, which is more than
the number of atoms in our observable Universe.
Under these circumstances, it becomes
more reasonable to assume that several would
turn out like ours. It’s like getting zillions and
zillions of darts to throw at the dart board,
Susskind says. “Surely, a large number of them
are going to wind up in the target zone.” And of
course, we exist in our particular Universe
because we couldn’t exist anywhere else.
It’s an intriguing idea with just one problem,
says Gross: “It’s impossible to disprove.”
Because our Universe is, almost by definition,
everything we can observe, there are no
apparent measurements that would confirm
whether we exist within a cosmic landscape of
multiple universes, or if ours is the only one.
And because we can’t falsify the idea, Gross
says, it isn’t science. Or at least, it isn’t science
in any conventional sense of the word. “I think
Gross sees this as science taking on some of the
traits of religion,” says Carr. “In a sense he’s
correct, because things like faith and beauty
are becoming a component of the discussion.”
And yet in the overlapping circles of cosmology
and string theory, the concept of a landscape
of universes is becoming the dominant
view. “I really hope we have a better idea in the
future,” says Juan Maldacena, a string theorist
at the Institute for Advanced Study in Princeton,
New Jersey, summing up the views of
many in the field. “But this idea of a landscape
is the best we have today.” The stakes are high:
string theorists know that pursuing an unverifiable
theory could look like desperation, but
they fear that looking for meaning in a meaningless
set of numbers may be equally fruitless.
Kepler’s error
At the core of this dilemma is a concept known
as the anthropic principle: the idea that things
appear the way they do because we live at a
certain spot in the Universe. It’s not a new concept,
and has previously been regarded more
as philosophy than science.
But some scientists say that it offers a useful
change of perspective. “It’s very important to
take into account stuff like this, or you can
come to completely incorrect
conclusions about the Universe,”
argues Max Tegmark, a
cosmologist at the Massachusetts
Institute of Technology,
Cambridge. “For example, you
might assume our Solar System
is typical, but a typical point in
space is some intergalactic void
where you can’t see a single
star.”
Failing to consider our observational
location has burned
scientists in the past. The sixteenth-
century German astronomer
Johannes Kepler spent
years trying to understand what
seemed to be the even, geometrical
spacing of our planets
from the Sun. Kepler searched
for meaning in the planets
because he thought our Solar
System was unique; today’s scientists understand
that our Solar System is but one of probably
billions in the Galaxy. Under such
circumstances it seems reasonable to assume
the planets are spaced according to little more
than random chance.
In much the same way as Kepler worried
about planetary orbits, cosmologists now
puzzle over numbers such as the cosmological
constant, which describes how quickly the Universe
expands. The observed value is so much
smaller than existing theories suggest, and yet
so precisely constrained by observations, that
theorists are left trying to figure out a deeper
meaning for why the cosmological constant
has the value it does.
Many are still searching
for some great unifying
theory that would explain
these variables. But others
have started to believe
that, like Kepler, today’s
physicists are looking for
meaning where there is
none. “In recent years, it
was looking more and
more to me like the laws of
nature were environmental,”
says Susskind, who has
just written a book making
this argument (L. Susskind
The Cosmic Landscape:
String Theory and the Illusion
of Intelligent Design.
Little Brown, 2005). He
suspects that there are
many universes, all with
different values for these
variables. Just as human
life had to evolve on a planet with water, he says,
perhaps we also had to evolve in a Universe
where atoms could form.
Until recently, Susskind was in the minority.
Hints of multiple universes, however, were
given by a cosmological theory known as inflation.
Inflation is the leading theory of the early
Universe; it postulates that a period of rapid
early expansion created the flat and uniform
cosmos we see today. One version of inflation
theory, devised in the early 1980s, suggests that
inflation occurred even before the Big Bang. In
this version, the expanding cosmos was foamy
and energetic, says Steven Weinberg, a
researcher at the University of Texas, Austin.
“Every once in a while, one part of the Universe
would expand and become a Big Bang,” he says.
“And these Big Bangs would all have different
values for their fundamental constants.”
Strings attached
In 1987, Weinberg made a prediction that
turned out to support the idea of an anthropic
Universe. Preliminary observations indicated
that the cosmological constant was zero, but
Weinberg reasoned that if the constant was
constrained by our anthropic perspective then
it would be small, so as not to interfere with the
formation of galaxies, stars and planets, but
non-zero, because it would be essentially
random. “That prediction has since been confirmed
by observations of supernovae and the
microwave background,” says Weinberg, who
admits he was a reluctant convert to the idea.
The latest circumstantial arguments for
multiple universes come from string theory.
String theory posits that tiny strings vibrating
in the fabric of space-time give rise to the multitude
of particles and forces in the macroscopic
Universe. Although string theory lacks
experimental support, it attracts broad interest
because it seems to offer a route to a grand theory
of everything — a way to unify relativity
with quantum mechanics.
But as theorists developed string theory,
they discovered that the equations gave rise to
multiple solutions, each of which represented
a universe with different physical properties.
“The hope always was that we would understand
why one solution was picked out,” says
Joe Polchinski, a string theorist at the Kavli
Institute. But despite their best efforts, after
two decades theorists are still stuck with a million
different solutions for the equations, and
therefore a million potential universes.
This landscape of solutions, as it became
known in the community, was both troubling
and intriguing. On the one hand, the theory
stubbornly refused to yield a single solution
resembling our own cosmos, but then, some
argued, that might also explain the cosmological
constant’s apparent randomness. If these
many solutions actually represent millions of
universes, then the idea that one had worked
out just right for us wasn’t so far-fetched.
Ignorance is bliss
The snag was that one million universes wasn’t
enough. To explain the perfectly adjusted cosmological
constant one would need at least 1060
universes, says Polchinski. Then, in 2000, he
and Raphael Bousso at the Lawrence Berkeley
National Laboratory in Berkeley, California,
calculated that there could be a lot more than a
million solutions. “The calculation had such
topological complexity that you could potentially
get 10500 universes,” Polchinski says. With
so many solutions, says Weinberg, it becomes
easier to imagine that we happen to live in a
Universe that seems tailored for our existence.
Easy to imagine, hard to prove. Because
other universes would be causally separated
from our own, it seems impossible to tell
whether our cosmos is the only one, or one of
many. Most scientists find this disturbing.
Talk of a Universe fine-tuned for life has
already attracted supporters of intelligent
design, who claim that an intelligent force
shaped evolution. If there’s no way to tell
whether the values of scientific constants are
a coincidence, the movement’s followers
argue, then why not also consider them
evidence of God’s handiwork?
The anthropic reasoning behind the landscape
of universes is disturbing on another
level, says Gross. Most theories grow stronger
with each observation that matches their predictions.
However, for the anthropic principle,
random chance is the main factor. Patterns
and correlations, the stones from which scientific
theories are built, weaken it. In other
words, he says: “The power of the principle is
strongest where you have ignorance.”
That may be, but measurements that could
support anthropic reasoning are in the works.
In 2007, researchers at Europe’s CERN particle
physics centre in Geneva, Switzerland, will
turn on the Large Hadron Collider, a massive
accelerator that will probe particle energies
never before seen by researchers. The accelerator
might detect so-called supersymmetric
particles, predicted by some as a way of unifying
the strong and weak nuclear forces with
the electromagnetic force, an important step in
uniting all the forces of physics within a single
theory.
These particles could also hint at whether
we live in one of many universes, says Nima
Arkani-Hamed, a string theorist at Harvard
University in Cambridge, Massachusetts. If
the collider detects certain types of supersymmetric
particles, he says, it will indicate
another fine-tuning in the cosmos — the ratio
of the weak nuclear force to the strength of
gravity. The anthropic argument is the same:
if the number was off by as little as one part in
1030, then we would not be here to discuss it.
It might seem that the detection of a second,
perfectly tuned number would only exacerbate
the debate, but Arkani-Hamed argues that it
will have the opposite effect. Unlike the cosmological
constant, which has had a controversial
history even in cosmology, this
fine-tuning would appear in the standard
model, which most physicists consider to be
the most complete physical theory ever developed
and tested. It would strengthen the
case for the arbitrary nature of certain fundamental
constants, Arkani-Hamed contends:
“These measurements wouldn’t directly prove
or disprove the landscape, but they would be a
very big push in that direction.”
Leap of faith
Still, many scientists distrust the concept and
continue to seek alternative explanations.
Among them is Lisa Randall, also at Harvard.
Randall suspects that multiple universes are a
mirage resulting from the unrefined equations
of string theory. “You really need to explore
alternatives before taking such radical leaps of
faith,” she contends. And with no foreseeable
way to detect other universes, Gross feels that
such leaps of faith should not be taken. “I feel
that it’s a rather extreme conclusion to reach at
this point,” he says.
Susskind, too, finds it “deeply, deeply troubling”
that there’s no way to test the principle.
But he is not yet ready to rule it out completely.
“It would be very foolish to throw away the
right answer on the basis that it doesn’t conform
to some criteria for what is or isn’t
science,” he says.
Gross believes that the emergence of multiple
universes in science has its origins in theorists’
20-year struggle to explain the finely
tuned numbers of the cosmos. “People in
string theory are very frustrated, as am I, by
our inability to be more predictive after all
these years,” he says. But that’s no excuse for
using such “bizarre science”, he warns. “It is
a dangerous business.” ■
Geoff Brumfiel is Nature’s physical sciences
Washington correspondent.
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shezmear
Posts: 573
Joined: Mon Oct 31, 2005 2:48 pm

Post: # 9660Post shezmear »

I love how you post this stuff bomo...
By their deeds shall you know them.
J.C
User avatar
bomohwkl
Posts: 741
Joined: Thu May 06, 2004 4:56 pm

Post: # 9661Post bomohwkl »

I was cleaning my hard disk and i found a few papers that I have saved from Nature ( the most reputable journal of science). I just would like to share. Besides, not a lot of people have such access of such journals as I do.


ERRATA:
It’s like you’re throwing
darts, and the bullseye is just one part in 10^120
of the dart board,”
User avatar
shezmear
Posts: 573
Joined: Mon Oct 31, 2005 2:48 pm

Post: # 9665Post shezmear »

bomohwkl wrote:I was cleaning my hard disk and i found a few papers that I have saved from Nature ( the most reputable journal of science). I just would like to share. Besides, not a lot of people have such access of such journals as I do.


ERRATA:
It’s like you’re throwing
darts, and the bullseye is just one part in 10^120
of the dart board,”
I don`t understand...
By their deeds shall you know them.
J.C
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Robanan
Posts: 949
Joined: Sat Dec 04, 2004 3:27 pm
Location: Denmark
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Re: OUTRAGEOUS FORTUNE

Post: # 10294Post Robanan »

This VIDEO will help you understand what is bomo here talking about.
The essence of Consciousness, is the ability to Create, Process, Transmit and Receive Information Autonomously.
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