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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">More
on black holes.<SPAN style="mso-spacerun: yes"> </SPAN>There are a number
of theories in the world of theoretical physics (not just the world of Buddhism)
in which the universe is cyclical—it dies and from its cinder is born
again.<SPAN style="mso-spacerun: yes"> </SPAN>One of those is my Big Bagel
Theory.<SPAN style="mso-spacerun: yes"> </SPAN>Others include Max
Tegmark’s toroidal theory, a theory in which the cosmos is also curved like a
doughnut, and a theory in which “branes”—skin-like surfaces on which universes
spread—periodically meet.<SPAN style="mso-spacerun: yes"> </SPAN>In most
of these theories the universe ends in a big crunch that’s the mirror opposite
of the big bang, then a new universe pops out of the singularity of that
crunch.<SPAN style="mso-spacerun: yes"> </SPAN></FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">A
question I’ve been pondering, and occasionally muttering about on paleopsych
over the last year or so, goes something like this.<SPAN style="mso-spacerun: yes"> </SPAN>Can we or whatever beasts are burped out
after us by the creative cosmos manage to sum up what we’ve learned and pass it
through the eye of the needle, through the singularity of the big crunch, and on
to whatever cosmos comes after us?<SPAN style="mso-spacerun: yes">
</SPAN>In other words, can universes learn from their parents?</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">The
answer would have been “no” a year or two ago.<SPAN style="mso-spacerun: yes"> </SPAN>Information, said the party line, can’t
pass through a singlurity—it can’t stream through the infinitessimal squinch in
time and space that makes for big bangs, big crunches, and black holes.<SPAN style="mso-spacerun: yes"> </SPAN>Well, now the view of just how much a
singularity turns all information into non-information seems to be
changing.<SPAN style="mso-spacerun: yes"> </SPAN>First Stephen Hawking
changed his mind in the summer of 2004 and decided that information can, indeed,
sift into—and, more important, out of—the singularity of a black
hole.</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">Now
a bunch of other theoretical physicists are discovering ways their theoretical
structures also make the sluicing of data through the eye of the needle, through
a singularity, possible.</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">Which brings us back to the question—can one cosmos pass
its wisdom on to the cosmos that comes after it?<SPAN style="mso-spacerun: yes"> </SPAN>Can universes learn, then pass their
knowledge on from one generation to the next and through the next to universes
ten generations down the line?<SPAN style="mso-spacerun: yes"> </SPAN>Can
information scrunchers like us humans possibly become part of this process?<SPAN style="mso-spacerun: yes"> </SPAN>Can we—or can our great, greate, great,
grandchildren a million generations down the line—find ways to compress
knowledge so it passes through the big crunch on to the next big
bang?</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">The
answer has shifted from what it was two years ago.<SPAN style="mso-spacerun: yes"> </SPAN>Then it was an unequivocal “no”.<SPAN style="mso-spacerun: yes"> </SPAN>Now it’s just conceivably
“yes”.<SPAN style="mso-spacerun: yes"> </SPAN>Howard</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">Ps.
For those who don’t know the Bloom Big Bagel Theory, conceived in 1959, then
supported in surprising ways when we discovered in 1998 that the universe is
accelarating in its expansion, I’ll toss in an old summary below.<SPAN style="mso-spacerun: yes"> </SPAN>And below that is an article summing up
the new views on information’s passage through and/or out of black holes and, by
implication, other singularities.</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">The
Big Bagel Theory.<SPAN style="mso-spacerun: yes"> </SPAN>We can do this
the easy way, or we can do it the hard way.<SPAN style="mso-spacerun: yes"> </SPAN>The easy way is Rob Kritkausky’s
animation of the theory, which isn’t quite complete but gets a heck of a lot
across in a very small amount of time.<SPAN style="mso-spacerun: yes">
</SPAN>The animation is at </FONT><A href="http://www.bigbangtango.org/website/BigBagel.htm"><FONT face="Times New Roman">http://www.bigbangtango.org/website/BigBagel.htm</FONT></A></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">The
hard way is by using words.<SPAN style="mso-spacerun: yes"> </SPAN>Here
come the words:</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">The
Bloom Big Bagel theory of the cosmos says that at the infinitessimally small
point of the beginning of the Big Bang, two cosmoses whomped out, each into its
own curved plane of space. One is the cosmos in which we live. The
other is the cosmos of anti-matter. Do we need a silly, comic-book level
theory of this sort? We sure as heck do. When I went through several
hundred astrophysics papers trying to find the dates of nucleogenesis of the
various complex atoms--the atoms beyond hydrogen, helium, and lithium--I
couldn't find the information. Why? Because there is a subject in
astrophysics called nucleocosmochronology. You'd think that chronologists
of the birth of nucleii would try to figure out the date of the first iron atom,
the first, oxygen atom, the first potassium atom, and so on. But,
no. There's something else on nucleocosmochronologist's minds. It's
a simple question. Why is there so much ordinary matter in this universe
and so little anti-matter? Theory says that the amount of ordinary matter
and anti-matter should be the same. So where did all the anti-matter
go? The Bloom Big Bagel Theory of the Cosmos is toroidal.<SPAN style="mso-spacerun: yes"> </SPAN>In topology, that means it’s
doughnut-like.<SPAN style="mso-spacerun: yes"> </SPAN>Big Bagel Theory
says to idiots like me, "Hey, nut case, the missing anti-matter went into a
negative universe, a universe in which time runs in reverse, a universe in which
its obstreperous backwardness actually fits."<SPAN style="mso-spacerun: yes"> </SPAN>Meanwhile, astrophysicists are now
asking why the universe's elements--novas, stars, and galaxies--accelerate away
from each other once they pass a certain point. They've tried a bunch of
names to account for whatever the cause might be--negative gravity,
quintessence, the cosmological constant, and, this year's favorite, dark
energy. But Big Bagel theory says that a curved space represents a curve
in gravity. Gravity tells space how to bend. Reach the highpoint of
the bagel and you begin to slide down a gravity curve. You begin to
accelerate. You do it for two reasons simultaneously (two reasons
that are simultaneous and seem each others opposites may be instances of Niels
Bohr's complimentarity). Once you get over the hump, gravity turns
negative--it pushes you away from a common gravitational center instead of
toward that center. And once you get over the hump, you're being pulled by
the gravity of the anti-universe. When the two universes meet at the outer
limits of the Big Bagel they annihilate to a pinprick of energy and are back
where they started, in the center, big-banging and big-bageling again.<SPAN style="mso-spacerun: yes"> </SPAN>The idea of an anti-universe gains a
peculiar kind of support--and a new kind of reality--from the concept that i=the
square root of minus one. There is no square root of minus one, so why
does it show up in calculations that actually predict things we can
measure? Because the square root of minus one doesnt' exist HERE. It
exists THERE...in the anti-universe on the underside of the bagel. Those
two universes were once one. They will be one again someday...when they
meet on the bagel's outer limit, its periphery. So it makes sense that the
math of this cosmos--our cosmos--has to use the math of the negative cosmos,
too. The matter universe and the anti-matter universe are twins and will
continue to be connected--even if only distantly--so long as they both
exist. </FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">________</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">Now
for the articles on the ways in which information could slip through a
singularity--</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman">Retrieved January 20, 2005, from the World Wide Web<SPAN style="mso-spacerun: yes">
</SPAN>http://www.newscientist.com/article.ns?id=mg18524836.500<SPAN style="mso-spacerun: yes"> </SPAN>Free E-Zines<SPAN style="mso-spacerun: yes"> </SPAN>Subscribe to Magazine<SPAN style="mso-spacerun: yes"> </SPAN>Customer Service 21 January 2005<SPAN style="mso-spacerun: yes"> </SPAN>Black holes, but not as we know them 22
January 2005<SPAN style="mso-spacerun: yes"> </SPAN>From New Scientist
Print Edition. Subscribe and get 4 free issues.<SPAN style="mso-spacerun: yes"> </SPAN>JR Minkel<SPAN style="mso-spacerun: yes"> </SPAN>JR Minkel is a writer in New York
City<SPAN style="mso-spacerun: yes"> </SPAN>More Stories Explore:
fundamentals<SPAN style="mso-spacerun: yes"> </SPAN>Explore: space <IMG SRC="cid:X.MA1.1106344697@aol.com" height=859 width=576 border=0 v:shapes="_x0000_i1025" DATASIZE="53331" ID="MA1.1106344697" ><SPAN style="mso-spacerun: yes"> </SPAN>Enlarge
image Black hole revolution<SPAN style="mso-spacerun: yes"> </SPAN>Enlarge
image Black holesTHEY are the most fearsome objects in the universe. They
swallow and destroy everything that crosses their path. Everyone knows that
falling into a black hole spells doom. Or does it? In the past few years, cracks
have started to appear in the conventional picture. Researchers on the quest for
a more complete understanding of our universe are finding that black holes are
not so black, and perhaps not holes either. Furious debates are raging over what
black holes contain and even whether they deserve the name.<SPAN style="mso-spacerun: yes"> </SPAN>The term "black hole" was coined in the
1960s by physicist John Wheeler to describe what happens when matter is piled
into an infinitely dense point in space-time. When a star runs out of nuclear
fuel, for example, the waste that remains collapses in on itself, fast and hard.
The gravitational attraction of this matter can overwhelm its natural tendency
to repel itself. If the star is big enough, the result will be a singularity.
Around the singularity lies an event horizon, a point of no return. Light cannot
escape once it passes beyond this boundary, and the eventual fate of everything
within it is to be crushed into the singularity.<SPAN style="mso-spacerun: yes"> </SPAN>But this picture always contained the
seeds of its own destruction. <B>In 1975 Stephen Hawking at the University of
Cambridge calculated that black holes would slowly but inexorably evaporate.
According to the laws of quantum mechanics, pairs of "virtual" particles and
antiparticles continually bubble up in empty space. Hawking showed that the
gravitational energy of the black hole could be lent to virtual particles near
the event horizon. These could then become real, and escape, carrying away
positive energy in the form of "Hawking radiation". Over time, the black hole
will bleed away into outer space.</B><SPAN style="mso-spacerun: yes">
</SPAN>This led to a problem dubbed the information paradox. While <B>relativity
seems to suggest that information about matter falling into a black hole would
be lost, quantum mechanics seemed to be suggesting it would eventually
escape.</B> <B>Hawking claimed the random nature of Hawking radiation meant that
while energy could escape, information could not. But last summer, he changed
his mind </B>(New Scientist, 17 July 2004, p 11). His reversal was just one part
of a larger movement to rethink the rules that govern black holes.<SPAN style="mso-spacerun: yes"> </SPAN>Much of the impetus for this rethink
comes from string theory, our best attempt to unify general relativity and
quantum mechanics. <B>Now 20 years old, string theory posits that space-time,
and everything in it, is composed of vibrating strings so small we will be lucky
ever to get evidence of their existence. Its big appeal is the promise that it
could unite general relativity and quantum mechanics, because one type of string
carries the force of gravity, while the vibration of the strings is random, as
predicted by quantum mechanics.</B><SPAN style="mso-spacerun: yes">
</SPAN><B>String theory was first applied to black holes in the mid-1990s.
Andrew Strominger and Cumrun Vafa of Harvard University began to work on the
information paradox by imagining what the inside of a black hole might be like.
The researchers found that string theory would allow them to build highly dense
little structures from strings and other objects in string theory, some of which
had more than three dimensions. These structures worked just like black holes:
their gravitational pull prevents light escaping from them.<SPAN style="mso-spacerun: yes"> </SPAN>“The number of ways strings can be
arranged in black holes is amazingly large”</B>Strominger and Vafa counted how
many ways the strings in these black holes could be arranged, and found this was
amazingly large.<SPAN style="mso-spacerun: yes"> </SPAN>The calculation
was heralded as a huge validation for string theory. In the 1970s, Hawking and
Jacob Bekenstein, then at Princeton University, had calculated the entropy of a
black hole using quantum mechanics. <B>The entropy of an object is roughly a
measure of the amount of information it can contain. In particular, it measures
the number of different ways the parts making up an object can be arranged. It
just so happened that the number of ways that Strominger and Vafa calculated
that strings could be arranged in a black hole exactly matched the entropy
calculated by Hawking and Bekenstein.</B><SPAN style="mso-spacerun: yes">
</SPAN>Fuzzballs But this did not tell physicists how those strings were
arranged. Over the past year, <B>Samir Mathur of Ohio State University and his
colleagues</B> have begun to look at what string configurations there could be
in black holes. They <B>found that the strings would always connect together to
form a large, very floppy string, which would be much larger than a point-size
singularity.</B><SPAN style="mso-spacerun: yes"> </SPAN><B>Mathur's group
calculated the total physical sizes of several stringy black holes, which they
prefer to call "fuzzballs" or "stringy stars". To his surprise, they found they
were the same size as the event horizon is in traditional theory.</B> "It is
changing our picture of the black hole interior," says Mathur. <B>"It would
really mean the picture of the round hole with a black dot in the centre is
wrong."<SPAN style="mso-spacerun: yes"> </SPAN>Mathur's fuzzball does away
with the idea of the event horizon as a sharp boundary.</B> In the traditional
view, the event horizon is a well-defined limit. Objects passing particular
points in space at particular moments in time are guaranteed to end up being
pulverised at the black hole singularity. <B>In the fuzzball picture, the event
horizon is a frothing mass of strings</B>, not a sharp boundary.<SPAN style="mso-spacerun: yes"> </SPAN>The fuzzball picture also challenges the
idea that a black hole destroys information. In Mathur's description, there is
no singularity. The mass of strings reaches all the way to the fuzzy event
horizon. This means <B><SPAN style="BACKGROUND: yellow; mso-highlight: yellow">information can be stored in
the strings and imprinted on outgoing Hawking radiation</SPAN></B>.<SPAN style="mso-spacerun: yes"> </SPAN>So what happens to the information that
falls into a black hole? <B>Imagine pouring cream into black coffee.</B> <B>Drop
the coffee and cream into the old-style black hole and they will go to the
singularity and be lost. You will never see the results of the mixture. But drop
your coffee and cream onto a Mathur fuzzball and information about the
cream-coffee mixture will be encoded into string vibrations. Hawking radiation
that comes out can carry detailed information about what happened to each
particle of cream and every particle of coffee.</B> "There's no information
problem. It's like any other ball of cotton," says Mathur. This picture is very
preliminary, cautions Vafa. Mathur has not yet calculated exactly how his model
applies to large black holes or understood how a black hole evolves over
time.<SPAN style="mso-spacerun: yes"> </SPAN><B>Gary Horowitz of the
University of California, Santa Barbara, and Juan Maldacena of the Institute for
Advanced Study in Princeton, New Jersey, also recently proposed that information
can get out of a black hole. But unlike Mathur, they believe that black holes do
contain a singularity at their heart. They suggested that information might
escape by means of quantum teleportation.</B> This allows the state of one
particle to be instantly teleported to another. So Horowitz and Maldacena
suggested that information could pass from matter hitting the singularity to
outgoing Hawking radiation.<SPAN style="mso-spacerun: yes"> </SPAN>“The
most information any black hole would possibly retain is just half a bit -
everything else will eventually escape”But to make their calculation work, they
had to assume that infalling matter and outgoing radiation would not collide
with each other. If they did, this could disrupt the teleportation process.
Quantum information theorists Daniel Gottesman of the Perimeter Institute for
Theoretical Physics in Waterloo, Canada, and John Preskill of the California
Institute of Technology in Pasadena say such disruption could occur very
easily.<SPAN style="mso-spacerun: yes"> </SPAN>That seems to raise a
problem for Horowitz and Maldacena. But last summer, Seth Lloyd of the
Massachusetts Institute of Technology worked out that all such disruptions would
actually cancel each other out. Then Lloyd calculated that the most information
a black hole would possibly retain permanently was just half a bit - everything
else will eventually escape. This applies to all black holes, whether they are
supermassive ones at the heart of a galaxy (see "Giants of the universe") or
mini black holes created in a particle accelerator (see "Baby black
holes").<SPAN style="mso-spacerun: yes"> </SPAN>But Gottesman and Preskill
have a second criticism that might be more fatal to the teleportation picture.
They showed that the effect could allow faster-than-light communication, which
is taboo in relativity. <B>The teleportation calculation relies on the
assumption that every piece of matter inside a black hole has the same quantum
state.</B> <B>Although quantum mechanics allows one particle to have an
instantaneous effect on the quantum state of another, this cannot be used to
communicate. For example, if one person, Alice, measures the quantum state of a
particle that is linked with a particle held by her friend, Bob, the effect of
this measurement will be instantaneously communicated to Bob's, but there is no
way to use this to communicate faster than light, because Alice needs to tell
Bob what kind of measurement process she carried out on her particle, before he
can decode the meaning of the change he sees.</B> That information has to travel
to Bob in the normal way.<SPAN style="mso-spacerun: yes"> </SPAN>Black
hole communication <B>However, if Alice throws her particle into a black hole,
the researchers found the measurement will be immediately constrained to the
quantum state of the black hole. This would have an effect on Bob's particle
that he could determine without needing the extra information from Alice.</B>
<B>Gottesman</B> concludes that the teleportation idea cannot work very well.
Indeed, he<B><SPAN style="BACKGROUND: yellow; mso-highlight: yellow"> wonders if
the framing of the information paradox is wrong in a way that is not yet
understood. "My own guess is somehow we're asking a stupid question," he
says.</SPAN></B><SPAN style="mso-spacerun: yes"> </SPAN>The scenario also
bothers quantum-gravity theorist Ted Jacobson of the University of Maryland, who
still believes that the information that falls into black holes is lost forever
to those outside the black hole. He finds the teleportation picture particularly
unconvincing. "I put it in the category of desperate attempts to make
information come out," he says. And even the researchers themselves aren't sure
they are right. "We suggested one possibility," says Horowitz, but he admits it
doesn't have a good basis in string theory yet. "So I can't say we are confident
this is the right picture."<SPAN style="mso-spacerun: yes">
</SPAN>Jacobson argues that the connection between the outside and inside of a
black hole is so complicated in string theory that no one can be sure they have
ruled out the possibility of information leaking out of our space-time. People
may be simply assuming the conclusion that they want for their own reasons. "I
see no problem with letting the darn stuff fall down the drain. Why are people
so afraid of the singularity?"<SPAN style="mso-spacerun: yes"> </SPAN>The
problem, says Vafa, is that the concept of information could be very subtle in
string theory, and not yet well-defined. "Information loss is a critical
question, but our understanding of black holes is too primitive."<SPAN style="mso-spacerun: yes"> </SPAN>So whether information can escape from
black holes or is destroyed remains a topic of intense debate. But there might
turn out to be a third option.<B> One competing theory to string theory is
called loop quantum gravity, pioneered by, among others, Lee Smolin </B>of the
Perimeter Institute in Waterloo, Canada.<B><SPAN style="BACKGROUND: yellow; mso-highlight: yellow"> It proposes that space-time
is constructed of loops even smaller than strings. Joining loops together
creates a mesh of nodes and branches called a spin network.</SPAN></B> <B>The
advantage of this model is that<SPAN style="BACKGROUND: yellow; mso-highlight: yellow"> space-time itself can be
built out of these networks</SPAN> instead of having to be assumed, as it is in
string theory.</B><SPAN style="mso-spacerun: yes"> </SPAN>Abhay Ashtekar
of Pennsylvania State University in Pittsburgh and Martin Bojowald of the Max
Planck Institute for Gravitational Physics in Golm, Germany, have studied <B>a
model of a black hole created using spin networks. They found the equations that
describe space-time continue to apply in an orderly way even at the singularity
itself.</B> This is very different to the conventional picture, in which the
equations of physics break down when space-time collapses. <B><SPAN style="BACKGROUND: yellow; mso-highlight: yellow">It means that information that
reaches the singularity could survive there, encoded in the spin
networks.</SPAN></B> <B>As far as Ashtekar and Bojowald can tell, the
information trapped in a black hole will be unable to escape via Hawking
radiation. Wait long enough, however, and it will survive, eventually rejoining
the rest of the universe when the black hole evaporates.</B><SPAN style="mso-spacerun: yes"> </SPAN>So whatever the theory that eventually
supersedes relativity, it seems a good possibility that black holes may be just
a little less dramatic than we thought. After all, who's afraid of a big ball of
string?<SPAN style="mso-spacerun: yes"> </SPAN>From issue 2483 of New
Scientist magazine, 22 January 2005, page 28 Giants of the universe While debate
rages over what black holes really are, <B>the astronomical evidence that every
galaxy is built around a supermassive black hole is stronger than ever.</B><SPAN style="mso-spacerun: yes"> </SPAN>Observations made with the Hubble Space
Telescope have found that every galaxy has a mass at its core millions of times
as massive as our sun. <B>The bigger this mass, the larger the size of the
"galactic bulge" - the number of stars clustered around the galactic
centre.<SPAN style="mso-spacerun: yes"> </SPAN>The speed with which stars
orbit the centre of a galaxy reveals the mass of the object they are
orbiting,</B> and very careful measurements can reveal its size too. For a
handful of galaxies, including the Milky Way, the central mass is known to be
crammed into a space just a few times as wide as the distance between the Earth
and the sun, indicating that what lies within is so dense, it must be a black
hole.<SPAN style="mso-spacerun: yes"> </SPAN><B>Some young galaxies emit
copious amounts of high-energy radio and X-ray radiation. Lines in X-ray spectra
taken from these objects are shifted as if the rays had struggled to escape from
the strong gravitational field of a supermassive black hole.</B> <B><SPAN style="mso-spacerun: yes"> </SPAN>The closest object to the centre of our
galaxy is a bright, compact source of radiation known as Sagittarius A*. X-ray
flares coming from it, and picked up by the Chandra X-ray telescope, are thought
to be the dying gasps of matter falling into a supermassive black hole.</B><SPAN style="mso-spacerun: yes"> </SPAN>Baby black holes You don't have to go to
space to find a black hole: mini versions could be created to order, right here
on Earth. That's what some physicists claim will be possible using the world's
most powerful particle accelerator, due to turn on in 2007.<SPAN style="mso-spacerun: yes"> </SPAN>Currently under construction <B>at the
CERN laboratory in Geneva, the Large Hadron Collider</B> will smash protons
together with a collision energy of 14,000 billion electronvolts. This<B> might
just be enough to create several black holes every second</B>, provided some
strange ideas about unknown physics turn out to be right. Each mini wonder would
weigh no more than a few micrograms and be smaller than a speck of dust.<SPAN style="mso-spacerun: yes"> </SPAN>A black hole is thought to form when the
core of a massive star collapses under its own weight and is crushed to a point.
Vast amounts of matter weighing more than a few suns are needed to produce
gravity strong enough for this to happen.<SPAN style="mso-spacerun: yes">
</SPAN>Yet the special theory of relativity gives a clue to making black holes
in the laboratory. Einstein used the theory to show that <B>energy is equivalent
to matter. So black holes should also pop into existence when vast amounts of
energy are concentrated into a point, and that's exactly what happens when
particles smash together at extreme energies.</B><SPAN style="mso-spacerun: yes"> </SPAN>But there's a snag. According to our
existing knowledge of particles and the forces that operate between them, the
minimum energy needed to make a black hole this way is 10 million billion times
more than LHC can produce. And the chances of ever building a particle
accelerator that can reach such energies are virtually nil.<SPAN style="mso-spacerun: yes"> </SPAN>In the past few years though, the
prospects for making black holes in the lab have improved. This is down
to<B><SPAN style="BACKGROUND: yellow; mso-highlight: yellow"> a theory that says
gravity is actually much stronger than we think. Huge masses are needed for the
force of gravity to become important in everyday life, and this feebleness
puzzles physicists. Some suggest that it can be explained if space has extra,
invisible dimensions that only gravity can reach.</SPAN></B> <B>The
gravitational force leaks away into them,</B> while our universe and the
particles spewing out of accelerators are trapped in three dimensions, rather
like specks of dust on the surface of a soap bubble.<SPAN style="mso-spacerun: yes"> </SPAN><B>If the idea is right, gravity could
be much stronger when it applies over distances so small that there is no chance
of leakage into other dimensions.</B> Pack enough energy into a 10-20-metre
space and it could be enough to create a black hole.<SPAN style="mso-spacerun: yes"> </SPAN>These mini curiosities will evaporate
within 10-26 seconds, losing most of their mass by radiating energy, as
predicted by Stephen Hawking. A group led by Roberto Emparan at the University
of the Basque Country in Bilbao, Spain, calculated that most of this Hawking
radiation should appear as particles that can be spotted by detectors. If
Emparan is right, the LHC could provide the first evidence for Hawking radiation
from a black hole.<SPAN style="mso-spacerun: yes"> </SPAN>A computer
simulation devised by Bryan Webber at the University of Cambridge and others
creates mini black holes from LHC-style collisions. The simulation shows that
the structures should decay into a large number of high-energy particles, which
would be sprayed all over the detector. If the theory is right, researchers
expect to see many more of these striking events than they might otherwise. By
measuring the energy and momentum of the particles radiated, they hope to
measure the mass of the mini marvels.<SPAN style="mso-spacerun: yes">
</SPAN>Valerie Jamieson<SPAN style="mso-spacerun: yes"> </SPAN>New
Scientist magazine © Copyright Reed Business Information Ltd.<SPAN style="mso-spacerun: yes"> </SPAN>Home Breaking News Explore by Subject
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<DIV><FONT lang=0 face=Arial size=2 FAMILY="SANSSERIF" PTSIZE="10">----------<BR>Howard Bloom<BR>Author of The Lucifer Principle: A
Scientific Expedition Into the Forces of History and Global Brain: The Evolution
of Mass Mind From The Big Bang to the 21st Century<BR>Visiting Scholar-Graduate
Psychology Department, New York University; Core Faculty Member, The Graduate
Institute<BR>www.howardbloom.net<BR>www.bigbangtango.net<BR>Founder:
International Paleopsychology Project; founding board member: Epic of Evolution
Society; founding board member, The Darwin Project; founder: The Big Bang Tango
Media Lab; member: New York Academy of Sciences, American Association for the
Advancement of Science, American Psychological Society, Academy of Political
Science, Human Behavior and Evolution Society, International Society for Human
Ethology; advisory board member: Youthactivism.org; executive editor -- New
Paradigm book series.<BR>For information on The International Paleopsychology
Project, see: www.paleopsych.org<BR>for two chapters from <BR>The Lucifer
Principle: A Scientific Expedition Into the Forces of History, see
www.howardbloom.net/lucifer<BR>For information on Global Brain: The Evolution of
Mass Mind from the Big Bang to the 21st Century, see
www.howardbloom.net<BR></FONT></DIV></FONT></BODY></HTML>