Entheon Village at Burning Man
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© 2007 Entheon Village
Tag Archives: SCIENCE & TECH./TECHNOLOGY
Cellulose & nanotubes combine to create cheap, flexible & paper-thin batteries
Storing electricity: It looks good on paper
Aug 14th 2007
From Economist.com
Cellulose and nanotubes combine to bring flexible batteries to the world
ELECTRICITY-storage devices are getting more flexible, in a literal
sense as well as in their design. This week sees the unveiling of the
most robust but flexible battery ever. Pulickel Ajayan and his
colleagues at Rensselaer Polytechnic Institute in New York made it by
mixing carbon nanotubes (cylindrical, electrically conductive molecules
made of carbon atoms) with cellulose, the stuff of paper. The result,
which they report in this week’s Proceedings of the National Academy of Sciences, is an energy store that is cheap, flexible and paper-thin.
Broadly speaking, devices for storing electricity come in two
varieties: batteries and capacitors. Batteries contain lots of
incipient electricity in the form of chemicals that, when they react,
can be used to generate an electric current. Such “high energy density”
devices, however, release their potential slowly. For a short, sharp
shock a capacitor is better. This is a low energy-density device, which
stores electricity directly by charging two conductive plates with
static. One plate is positive, the other negative. When the plates are
connected as part of a circuit, the charge flows rapidly between them
and produces a far more powerful current than a battery. This is ideal
for applications such as camera flashes.
The delightful thing about Dr Ajayan’s device is that with suitable
tweaking it can be used as a capacitor, a battery, or both. A sheet
containing two layers of nanotubes acts as a capacitor (each layer is a
plate). A sheet containing one layer, but with a coating of metallic
lithium on the other side, acts as a lithium-ion battery. A sheet with
two layers of nanotubes and a lithium coating can be switched from one
application to the other as required.
The crucial component for making this material is an exotic solvent
called 1-butyl, 3-methylimidazolium chloride. This molecular mouthful
has the rare ability among solvents of being able both to dissolve
cellulose and to act as an electrolyte—that is, a chemical that can
carry charge between the electrodes of a battery in the form of charged
molecules, or ions. It is thus integral both to the manufacturing
process of the device and to its operation.
The result is a material that works at temperatures from –80°C to
180°C, and can be rolled up, folded or cut like paper with no effect on
its performance. It could be attached to folding solar panels of the
sort used in space missions, and back on Earth it could provide
portable power in deserts or at the poles.
The three-layer version, in particular, provides a unique hybrid
power supply. It has the characteristics needed for applications that
require both high-power pulses and steady, battery-like flow. Moreover,
it provides them both while charging and while discharging. Hybrid cars
are one such application. Many use dynamos to recover their energy of
motion when they brake. The recovered energy is normally stored in a
battery. However, such a car needs a burst of energy to get going
again. Dr Ajayan’s device could provide this more effectively than a
conventional battery.
Like the cells of a conventional battery, layers of supercapacitor
can be stacked together to increase output. Unlike conventional
batteries, however, no poisonous chemicals are used to make Dr Ajayan’s
device. That makes it promising for medical applications. Cellulose,
which makes up more than 90% of the weight of the devices, is already
used in implants. Carbon nanotubes are not fully tested in medical
applications, but should be inert. And the researchers did some
preliminary experiments using body fluids such as blood and sweat as
electrolytes (having sweated the 1-butyl, 3-methylimidazolium chloride
out first), and obtained encouraging results.
The next phase is to scale up the manufacturing process, with the
aim of making the material rather as you would convert wood-pulp to
newsprint. When you need more portable power, you may one day just pull
some off a roll, and go.
Is Science Fiction obsolete in an age when we can't even predict the present?
07.20.2007
Blinded by Science: Fictional Reality
Sci-fi helped make the present; now it's obsolete.
In a sulfurous chasm beneath Reality, lit by the orange glow from
what appears to be a river of molten Time, the serpent and the eagle
have reached their moment of final reckoning. The eagle swoops in for
the kill with talons extended, each mighty feather a-bristle with fury.
The serpent marshals what’s left of its coiled strength and turns its
fanged and slavering maw to meet the eagle’s gaping beak in a cosmic
kiss of death that will obliterate countless worlds, if not, in fact,
all of them.
Other than this, however—the design on the back of the Hawaiian-cut
shirt of a very old man investigating the bean dip over at the buffet
table—this gathering of the Science Fiction and Fantasy Writers of
America is palpably low on excitement. We’re on the 38th floor of a
Marriott hotel in Lower Manhattan, in a poky beige suite filled with
the same cheap, gestural furniture you find in those fake rooms that
get set fire to in fire-safety videos. And with the exception,
obviously, of this correspondent, we’re a fairly drab and subdued sort
of bunch. The demographic is middle-aged to old. The median shirt type
is sweat-. And there are several grown men apparently untroubled by the
fact that they’re wearing backpacks to a social event, yet troubled to
the point of madness and eczema by pretty much everything else.
Not that there’s anything wrong with that. This is, after all, a
gathering of fiction writers, and if fiction writers were good at going
to parties, well, most of them wouldn’t be fiction writers. Fiction is
a job for people with Big Ideas, not a flair for small talk—and with
the exception of Tom Wolfe, they’re generally too concerned with topics
like the human condition and the fate of the world to worry about their
appearance.
But this is science fiction, which I thought was supposed to be
different. I wasn’t hoping for Naomi Campbell in Vera Wang, just a few people dressed as Klingons,
perhaps, or painted green, even very faintly, or even just in a nice
houndstooth jacket or something, wildly gesticulating with the stem of
an unlit pipe. Energy is what I’m missing, that raw, spittly, unsocialized fizz that only an overexcited nerd can produce.
I suppose they may all be fatigued. After all, this is only Night
One of their annual Nebula Awards Weekend, and apparently many have
driven all the way across the country to be here.
Then again, it could also be the other thing—the thing that nobody’s
quite bringing up over the plastic cups of Yellowtail Merlot. Which is
that science fiction, the genre that lit the way for a nervous mankind
as it crept through the shadows of the 20th century, has suddenly and
entirely ceased to matter.
Granted, the ways in which it once did matter were never obvious.
The early days of science fiction, much like all its later days, found
its exponents bickering about what the genre was, what it should be,
and what its relationship was—if indeed it had one—with the more
established human pursuit known as Science.
One view, subscribed to by the towering French figure of Jules
Gabriel Verne, a man with a better claim to being the Father of Science
Fiction than anyone else, was that the genre should consider itself
almost a legitimate field of science proper, or at least should try to
hold itself to an analogous code of rigor. Verne conjured up imaginary
futures, and he sent his heroes on adventures armed with
as-yet-uninvented technologies. But he didn’t like to make scientific
leaps of faith just for the sake of the story. If Verne had his heroes
travel 20,000 Leagues Under the Sea in a pimped-out luxury
submarine, his personal code required him to explain how such a
contraption could be built according to the principles of physics as
they were understood at the time of writing: 1870. When he wanted to
send protagonists From the Earth to the Moon, he first had to
figure out how to get them there. It was rocket science, literally, but
the poor sap muddled through, eventually dispatching a three-man crew
from a space center in Florida riding a rocket made of newly discovered
aluminum at a speed of 12,000 yards per second. Fortunately, Verne had
been dead for 64 years by the time of the Apollo 11 mission in 1969 and
was thus spared the embarrassment of knowing the actual launch speed of
the aluminum craft that would carry the three men would be 11,424 yards
per second, and that part of the rocket would be named “Columbia,” not
his own ludicrously off-base suggestion, “Columbiad.”
The other view of science fiction, figureheaded in retrospect by
one Herbert George Wells—“H. G.” to pretty much everyone—was that
actual science was best left to actual scientists and science-themed
novelists should feel free to make stuff up if it helped uncover the
social and philosophical pitfalls in humanity’s road ahead. The Time Machine does not contain a blueprint for a working time machine, but it does contain a fairly rigorous and careful projection
of where early-20th-century capitalist society, and science itself,
might leave the species if certain changes weren’t made. In due course,
this approach would be given the label “soft science fiction,” as
opposed to the “hard,” nuts-and-bolts approach of Jules Verne, but the
schism was palpable even back then. According to lore, Verne publicly
accused Wells of “scientifically implausible ideas,” and Wells, firing
back in fittingly less forensic language, went public with the
observation that “Jules Verne can’t write his way out of a paper sack,”
further twisting the knife by failing to provide any details as how
such a large sack would be constructed or how Jules Verne might find
himself trapped within it.
Seems petty now, especially if one forgets that Verne and Wells were
fighting for the soul of an art form that would frame the great debates
of the modern age. It is hard to imagine how opponents of genetic
engineering would function without the noun-turned-prefix
“Frankenstein,” coined and imbued with dreadful power by Mary Shelley’s
1818 soft SF classic. As for “Orwellian,” where does one even begin? It
seems safe to say that the book 1984 is more an expression of George
Orwell’s revulsion with the actual totalitarian societies of 1948 than
a warning for future generations about the dangers of interactive
television, but the Soviet Union has collapsed and the meme of
Orwellianism lives on. Would we even be bothered by the proliferation
of surveillance cameras if we didn’t recognize the phenomenon as
“Orwellian” and know, therefore, that it is bad? Probably, but I think
you see my point.
Nor were SF’s gifts to humanity confined to the world of ideas.
Space precludes a full listing here of every real-world marvel lifted
straight from a work of futuristic fiction, but suffice it to say that
an artificial Earth-orbiting satellite was depicted in the sci-fi short
story “Brick Moon” by Edward Everett Hale in 1869. And though it would
irk Jules Verne no end, there’s also the fact that Leo Szilard, the man
who first theorized about a nuclear chain reaction, said he was
directly inspired by the work of H. G. Wells, in whose book The World Set Free, the term “atomic bomb,” as well as the vague mechanics of same, were first published.
Atomic bombs and satellites. Is there another field of literary fiction
to rival science fiction’s impact on the world? Chicklit? Chicano
realism? I rather think not.
All of which underscores the question of how it came to this: Why
are the heirs to such a grand tradition dipping their tortilla chips
into bean dip that has not even been decanted from its original plastic
container into a proper bowl? A plastic container, furthermore, to
whose circumference still adhere flapping shreds of cellophane safety
seal, the bulk of it clearly peeled off and discarded by someone who
has ceased to even give a damn? Why are they not holding their annual
meetings in some sort of gilded purpose-built pyramid while humanity
waits breathlessly outside to receive their inklings into our future?
Less poignantly but more shockingly, why are the science fiction
shelves of bookstores glutted with brightly colored works of “fantasy”
whose protagonists, judging by the covers, are shirtless bodybuilders
with Thor hairstyles fighting dragons with swords?
One clue, I would submit, is preserved in the fossil record that is the written work of one Michael Crichton.
There might be purists who’d argue that what Crichton writes are better
classified as techno-thrillers than works of science fiction, because
drawing petty distinctions is what being a purist is all about. But we
can surely all agree that for decades the man has been writing fiction
about science, and that his visions of the dangers of
as-yet-uninvented, or only-just-invented technologies have influenced
the way we think more than those of any other living novelist. “Could
we be looking at an Andromeda Strain scenario here?” news
anchors will even today inquire of experts whenever some mysterious
virus escapes from a lab. And no advance in our understanding of
dinosaur genetics can be reported without an assurance, tinged with
disappointment, that cloned T. rexes aren’t about to start trying to
eat our children the way they did in Jurassic Park.
Jurassic Park
But Jurassic Park, which came out in 1990, was pretty much it
for Crichton as an effective, hard-SF prognosticator. When he returns
to science fiction in 1999 with Timeline, something clearly has
changed. The topic is time travel, and true to his career-long hard-SF
principles, Crichton does at least sketch out for the reader how such a
thing might actually be possible. Sort of. The key, he ventures, might
be “quantum foam.” In the real world, quantum foam is a term used by
hard-core physicists standing beside vast, cantilevered chalkboards
full of squiggles to describe a theoretical state, or scale, or reality
at which particles of time and space blink in and out of existence in a
soup of their own mathematical justification. But in Crichton’s hands,
it’s actual foam. His heroes step into their time machine, pass
quickly through a metaphysical car wash of suds, and then spend the
rest of the novel jousting with black-armored knights and rolling under
descending portcullises. The science, in other words, is pure nonsense,
and the science fiction is not so much “hard” or “soft” as what you
might call, well, “bad.”
And there’s more of it in Crichton’s next book, Prey. The
threat this time is from nanotechnology and the “emergent behaviors” by
which large groups of tiny mindless entities shape themselves into a
single purposeful, highly intelligent organism (see Riverdance).
At least here the science is real; nanotechnology actually exists;
geese really do fly in a V formation without discussing it beforehand.
But in Crichton’s hands it’s just so much foam. His little particles
coalesce into swirling, malevolent clouds, but their intelligence maxes
out at roughly the IQ of a Nazi without a speaking part in a war movie,
just another evil presence for his heroes to outrun and outfox.
As to the question of what happened, not just to Crichton but to all
serious science fictionists, I reckon it boils down, like so many
things, to a pair of factors.
For one, it was around that time, the mid-1990s, that fiction—all
fiction—finally became obsolete as a delivery system for big ideas.
Whatever the cause—dwindling attention spans, underfunded schools,
something to do with the Internet—the fact is these days that if a Top
Thinker wakes up one morning aghast at man’s inhumanity to man, he’s
probably going to dash off a 300-word op-ed and e-mail it to The New York Times,
or better still, just stick it up on his blog, typos and all, not
cancel his appointments for the next seven years so he can bang out War and Peace
in a shed. If one truly has something to say, seems to be the
consensus, then why not just come out and say it? If your goal is to
persuade and be believed about the truth of a particular point, then
what would possess you to choose to work in a genre whose very name,
fiction, explicitly warns the reader not to believe a word she reads?
This trend in global epistemology would probably have made science
fiction irrelevant all by itself, I reckon. But the genre has an even
bigger dragon to slay with its new profusion of cheesy, dwarf-wrought
superswords: the scarcity of foreseeable future.
The world is speeding up, you may have noticed, and the rate at which it’s speeding up is speeding up,
and the natural human curiosity that science fiction was invented to
meet is increasingly being met by reality. Why would I spend my money
on a book about amazing-but-fake technology when we’re only a few weeks
away from Steve Jobs unveiling a cell phone that doubles as a jetpack
and a travel iron? As for the poor authors, well, who would actually
lock themselves in a shed for years to try to predict the future when,
in this age, you can’t even predict the present?
But the science fiction writers—not only of America, but of the
world—should not beat themselves up. If, through their talent and
imagination, our species has progressed to the point that it no longer
requires their services, then that should be a source of pride, not
shame, and the rest of us should be honoring these obsolete souls, not
making fun of their beards and backpacks in snarky, supposedly humorous
commentaries (you know who you are).
There is only one tribute commensurate with the debt. Let all of us,
today, march into the fiction section of our bookstores, with phasers
set to give-me-a-minute-I-know-what-I’m-doing, and quietly relabel the
shelves to set the record straight.
Let everything but the truth be “Fantasy,” I say, and let the
truth—the searing, unmanageable, discombobulating truth of the lives we
have invented for ourselves in a world it took artists to imagine—be
Science Fiction.
Second Life: An alternate universe
Second Life: An alternate universe
Friday, July 27, 2007
Second
Life is emerging as a powerful new medium for social interactions of
all sorts, from romance to making money. It may be the Internet's next
big thing.
Life is emerging as a powerful new medium for social interactions of
all sorts, from romance to making money. It may be the Internet's next
big thing.
By Jessica Bennett and Malcolm Beith
It's 1 a.m., and the “Dublin” nightclub is packed.
Women in trendy ball gowns and men in miniskirts dance to Bon Jovi.
Simon Stevens spins his wheelchair across the room, then leaps up
and starts dancing, a move he can execute only here in Second Life,
a 3-D virtual world that Stevens roams on his PC screen, using an
avatar – a graphic rendering of himself, liberated from his
cerebral palsy. “I flourish in Second Life,” says the 33-year-old,
who heads a disability-consulting firm called Enable Enterprises,
out of his home in England. “It's no game – it's a serious tool.”
Rhonda Lillie and Paul Hawkins live thousands of miles apart -
she in California, he in Wales – and until this week, had never met
face to face. But they've been dating for more than two years – in
Second Life. The detachment of meeting through their avatars
allowed them to open up to one another in a way they might never
have done in the real world. “We felt like we could go in and
really be ourselves,” Lillie says.
Anshe Chung is a virtual land baroness with a real-life fortune.
The woman behind the Anshe avatar is Ailin Graef, a former language
teacher living near Frankfurt, Germany. Three years ago she started
buying and developing virtual land in Second Life to see whether
its virtual economy could sustain a real life. Turns out it can:
Chung became Second Life's first millionaire in 2006. Her business,
Anshe Chung Studios, with a staff of 60, buys virtual property and
builds homes or other structures that it rents or sells to other
denizens of Second Life.
When San Francisco software developer Philip Rosedale dreamed up
the idea for Second Life in 1998, he never imagined that it might
have such an impact on the world at large. Just as Google sexed up
the way we search, and instant messaging altered the way we
interact, Second Life is fast becoming the next red-hot tool on the
Internet.
The numbers tell the story. Rosedale launched Second Life in
2001, but it got off to a slow start, reaching only 1.5 million
registered users in 2006. In the past year, membership has soared
to more than 8 million users – 2 million having signed on in the
last two months alone. This hypergrowth, driven mainly by word of
mouth, is now attracting competitors. South Korea's Cyworld started
out as a social-networking site, but has evolved into a
two-dimensional equivalent of Second Life, claiming 20 million
registered users from Asia to Latin America. Richard Branson's
Virgin recently announced plans to create its own 3-D community
called A World of My Own. By 2011, four of every five people who
use the Internet will actively participate in Second Life or some
similar medium, according to Gartner Research, which recently did a
study looking at the investment potential of virtual worlds. If
Gartner is to be believed (and it is one of the most respected
research firms in the field) this means 1.6 billion – out of a
total 2 billion Internet users – will have found new lives
online.
The power of Second Life lies in its utility for the gamut of
human activities. It's a potent medium for socializing – it
provides people with a way to express, explore and experiment with
identity, vent their frustrations, reveal alter egos. The likes of
MySpace and Facebook have already created online communities, but
they lack the three-dimensional potential for interaction that
Second Life provides. The people who are coming to this online
universe aren't just socializing, however. They're also doing
business, collaborating on research, teaching courses, dating and
even having sex. More than 45 multinational companies, including
the likes of American Apparel, IBM, General Motors and Dell are
beginning to use the medium for customer service, sales and
marketing. Many people are coupling the Second Life chat technology
with Skype, the popular audio Internet software, so they can talk
out loud while interacting inside the virtual world. Or they use
live streaming video to talk and see each other in real life
(sitting in front of a computer screen), as well as through their
avatars inside Second Life. “The unique thing about Second Life is
that it's immersive,” says Michael Rowe, head of IBM's digital
convergence team. “There's a huge opportunity here, just as in the
early days of the Internet.”
The medium sucks people in. A recent Dutch study found that 57
percent of Second Lifers spend more than 18 hours a week there, and
33 percent spend more than 30 hours a week. On a typical day,
customers spend $1 million buying virtual clothes, cars, houses and
other goods for their avatars, and total sales within this virtual
economy are now growing at an annual rate of 10 percent. As a
result, the money flowing through Second Life has attracted the
attention of the U.S. tax authorities, who are currently
investigating profits made in online businesses. And as it has
evolved, those with ill intentions have apparently discovered
Second Life, too. FBI agents are investigating possible gambling
operations, and the German TV news program “Report Mainz” recently
revealed allegations of child abuse in the virtual world. (Adults
were purportedly using their avatars to have sex with the avatars
of minors; they were expelled.)
Back in 1998, Rosedale simply hoped to create a vivid
three-dimensional landscape in which graphic designers could create
likenesses of their real-world ambitions – houses, cars, forests,
anything one might find in a virtual game like EverQuest or World
of Warcraft. Except Rosedale's creation wouldn't be a game: Second
Life had no rules, no levels, no dragons to slay. It was
open-ended, a digital landscape without regulations (much like the
Internet in its early days). It was created on software that
operates across multiple servers – a grid system that could easily
grow to accommodate a large, far-flung community. A user in Germany
could easily partner with a peer in Mexico to form their own
mini-community inside Second Life, based on common interests -
architectural designs, whatever. “It's basically Tom Friedman's
flat world,” says Philip Evans, an economist at Boston Consulting
Group who studies the industry. “It's the globalization of the
virtual world.”
At first, it was a world with no rules. Rosedale's company,
Linden Lab, oversaw the allotments of server space, which
translates into virtual real estate, but imposed no controls over
what went on inside the Garden of Eden it had created. A user's
representation in Second Life – his avatar – would be bound by no
social constraints. And anything could be built, as long as you
could write good enough code. The first pioneers – graphic
designers, for the most part – simply set up display spaces for
their technological projects. Then small communities with common
ideas and visions – much like an artistic community, say, in the
real world – sprang up. Since then, cities have grown, with urban
amenities from stores to clubs. Upon arrival, users are given the
PC commands that enable them to move around (walk, run, fly), dress
their avatar and communicate with others.
Newcomers agree to a list of several do's and don'ts, but within
the communities they form, residents can impose their own codes of
conduct. That laissez-faire attitude seems unsustainable – as
Second Life expands, eventually Linden Lab will have to figure out
a way to deal with the darker elements. In one of the first
troublesome incidents, residents reported last year that “gangs”
were forcing avatars out of public spaces. Rosedale declined to
intervene, saying his hope was that residents would organize to
police their own communities. They are currently doing so
successfully, with rare exceptions like the recent alleged
child-abuse incident.
For the moment, the social freedom is one of Second Life's big
draws. One can teleport to a nightclub like Dublin, find a pristine
beach on which to relax or start looking for business opportunities
right away. Crowded urban streets are lined with clothing stores,
car lots, supermarkets and nightclubs. Real estate is the hot
moneymaking market, with “islands” – private invitation-only plots
of Second Life land – selling for as much as $1,650.
Real-world entrepreneurs and businesses sense the opportunity.
With its large, densely settled population, which allows for
division of labor, and citizens universally armed with ownership
rights and the tools to produce just about anything, Second Life is
in some ways the ideal free market. Consider 40-year-old Peter
Lokke. Toiling away as a department manager at a Pathmark
supermarket, the New York native had dreamed of opening his own
design business, but “never pushed myself to get into it
professionally.” Two and a half years ago, a friend urged him to
chase his goals in Second Life. So Lokke paid $230 to Linden Lab to
buy a 375-square-meter plot of Second Life land, and opened up his
own clothing shop.
Today his avatar – a woman, incidentally – earns nearly $300 a
day selling clothing he designs for users to drag and drop onto
their avatars – twice what Lokke earned at the supermarket. As for
the clothes, he can make “infinite copies of anything.” Once he's
designed a T shirt, he can make millions of replicas at no
additional cost. “My supply is limitless,” he says. “There's no
bottom line. The costs are only what I pay Linden Lab.”
Linden Lab's “no control” policy allows for any income made
inside Second Life (the virtual world's currency is the Linden
dollar) to be cashed out through the company into U.S. dollars -
even deposited directly into your checking account (at an exchange
that has remained fairly stable at about 270 Linden dollars per
U.S. dollar). A product created in Second Life can also be sold
outside it – on eBay, for example, a private island was recently
listed for $1,395.
And unlike, say, Sony, which owns the rights to anything created
in EverQuest, Linden Lab has relinquished all intellectual-property
rights to creations in its world, spurring entrepreneurship.
Roughly 90 percent of Second Life's content is created by the users
themselves – Linden Lab built the basic architecture, like
“Orientation Island,” where users first create their avatar and
learn about Second Life. Indeed, the barriers to entry and to
commerce are so low, it is hard to imagine a more ideal business
environment for entrepreneurs, which may prove to be the biggest
driver of Second Life's growth. Lokke is so hooked, he says, “I'd
rather panhandle on the street than leave Second Life.”
A kind of alternate global economy is emerging in Second Life.
Linden Lab keeps information on transactions within the virtual
world to itself, but economists who study it closely forecast that
by the end of the year users will have spent 125 billion Linden
dollars in Second Life (about $460 million). About 5 billion Linden
dollars were changed (through the official currency exchange, the
LindeX) into $19 million in 2006. So far this year, they've
converted $37 million, much of it earned in virtual-world
transactions.
The multinational companies are using Second Life in a different
way: some are holding staff meetings where avatars representing
employees can discuss ideas via instant message, e-mail or Skype,
in a souped-up virtual office. Others are using it to connect to
customers. For instance, IBM is working with clients like Sears and
Circuit City to enhance the shopping experience: adviser avatars
can walk customers through models of, say, televisions, and
actually show them how the product might fit in the living room.
The 3-D, real-time experience also allows multiple customers, who
might not be together in the real world, to communicate while
shopping. A husband and wife on separate business trips can pick
out a new couch “together,” discussing the dimensions, color and
material in real time. “Second Life allows you to strike up a
natural conversation that you can't do on a two-dimensional Web
site,” says IBM's Rowe.
With face-to-face interaction on the decline in offices – where
it's easier to e-mail or videoconference than schedule a live
meeting – and companies increasingly use the Web for everything
from distribution to customer service, a virtual world offers the
potential to form relationships that are far more personal than
online forms or e-mail. Nissan, for instance, lets customers talk
to salespeople and even “test-drive” its new Sentra on a virtual
driving track in Second Life. The Dutch bank ABN AMRO has financial
advisers available as avatars.
That communication potential also makes Second Life attractive
as an educational and research tool. Architecture professor Terry
Beaubois began teaching a Montana State University course in Second
Life two years ago, remotely from his California home. Now at MSU
full time, he meets with classes each week out of “University
Island,” a mock campus that his students designed and built, with
classrooms, workshops and an oceanside gallery where they display their work. …
The idea has caught on. Although Beaubois's colleagues questioned his decision to teach through what they called a “computer game,” he's now head of MSU's Creative Research Lab and has the backing of the university's president (who has an avatar of his own). And more than 250 universities, including Harvard and MIT, now operate distance-learning programs in Second Life.
Students meet in virtual classrooms to discuss history and
political science. Teachers give virtual presentations, and lead
virtual field trips. Guest lecturers visit from all over the
world.
At the University of California, Davis, psychiatrist Peter
Yellowlees has set up virtual simulations to show students what
happens in a schizophrenic episode. Students can walk through a
replica of his psychiatric ward, analyzing terrifying voices and
eerie laughs, and can even see simulated schizophrenic
hallucinations. Many students find the images disturbing, but
Second Life helps them comprehend the “lived experience” of
patients who “constantly complain” that doctors don't understand
them, says Yellowlees.
True to the unofficial Second Life mantra – by the people, for
the people – patients themselves are utilizing that clinical
potential, too. “Brigadoon,” for instance, is a Second Life island
inhabited by a group of adults who suffer from Asperger's syndrome,
a form of autism characterized by awkward, eccentric and obsessive
behavior. Asperger's patients have trouble interacting socially and
don't perceive things that should come naturally – how to introduce
themselves or strike up a conversation, for instance. But in Second
Life, these patients are learning to interact in ways that would be
terrifying for them in real life. One sufferer has re-created a
favorite restaurant, where the group regularly meets. Gradually,
they are leaving their private island to venture into the rest of
Second Life, integrating into the larger community. “The one thing
that really amazes me about Second Life is the way it empowers
people,” says John Lester, the former Harvard Medical School
researcher who set up the group (and now works for Linden Lab). “It
frees them from the role of the biological device.”
Not everyone is convinced that Second Life is a good thing. Some
critics are uneasy with the idea of people's getting more and more
of their social activity online. “No matter how you beef it up with
little icons or fancy colors, [virtual worlds] don't have the
nuance of face-to-face interaction,” says Oxford University's Susan
Greenfield, who heads the U.K.'s Institute for the Future of the
Mind. It all depends, of course, on whether you see Second Life's
taking the place of ordinary social interaction or supplementing
it, or as just another kind of diversion – like “the 21st-century
version of the novel,” says Greenfield.
For diehard inhabitants, Second Life is a novel they won't put
down soon. Elizabeth Ward, who suffers from reflex sympathetic
dystrophy – a severe and chronic pain disorder that now keeps her
at home – says “the interaction goes one step further than anything
that could be achieved online.” Ward, who lives with her husband, a
software engineer, in Rhode Island, says her disability can make
life “frustrating and lonely,” but Second Life “has opened up
another world.” It's allowed her to continue working, to meet
people, to visit her son, who lives in Nevada, and her best friend
in India. She's gone sky diving, ice-skating – even played an
eight-piece violin concerto with a group of mermaids under the sea.
“I told my husband when I first started, 'I felt joy as I did when
I was little, playing with paper dolls',” Ward explains. “But now
the paper dolls are virtual and can interact with real people.”
Whether you think it's a pale imitation of reality or a vivid world
of the mind, it's captivating the globe.
© 2007 Newsweek, Inc.
The Large Hadron Collider (LHC): Beyond the standard model
Nature 448, 297-301 (19 July 2007) |
doi:10.1038/nature06079;
Published online 18 July 2007
Beyond the standard model with the LHC
John Ellis1
Abstract
Whether
or not the Large Hadron Collider reveals the long-awaited Higgs
particle, it is likely to lead to discoveries that add to, or
challenge, the standard model of particle physics. Data produced will
be pored over for any evidence of supersymmetric partners for the
existing denizens of the particle 'zoo' and for the curled-up extra
dimensions demanded by string theory. There might also be clues as to
why matter dominates over antimatter in the Universe, and as to the
nature of the Universe's dark matter.
The
unparalleled high energy of the Large Hadron Collider (LHC), with its 7
TeV per beam and its enormously high collision rate that should reach a
billion collisions per second, makes it a microscope able to explore
the inner structure of matter on a scale that is an order of magnitude
smaller than previously achieved. Results at the energies and distances
explored so far led physicists to successfully describe matter using
the standard model of particle physics1, 2, 3.
But this description is incomplete, and the standard model raises, but
leaves unanswered, many fundamental questions. Explanations are needed
for the origin of particle masses and the small differences seen in the
properties of matter and antimatter, as well as to establish whether
fundamental interactions can be unified. Moreover, the standard model
has no explanation for some of the basic puzzles of cosmology, such as
the origin of matter and the nature of the Universe's dark matter and
dark energy. There are high hopes that the LHC will help resolve at
least some of these basic issues in cosmology and in physics beyond the
standard model4.
Theoretical
calculations made using the standard model agree well with data
collected at lower-energy accelerators, such as at CERN's Large
Electron–Positron (LEP) accelerator in the 1990s and, more recently, at
the Tevatron proton–antiproton collider at Fermilab (Batavia, Illinois)5.
Data collected at LEP agreed with the standard model at the per-mille
level, and recent measurements of the masses of the intermediate vector
boson W (ref. 6) and the top quark7
agree well with standard-model predictions. But the theoretical
calculations are valid only with an ingredient that has not yet been
observed — the notorious Higgs boson. Without this missing ingredient,
the calculations yield incomprehensible, infinite results8, 9.
The agreement of the data with the calculations implies not only that
the Higgs boson (or something equivalent) must exist, but also suggests
that its mass should be well within the reach of the LHC5.
In
this review, I discuss the likelihood of finding the Higgs boson and
what other physics beyond the standard model the accelerator might
reveal.
Searching for symmetry breaking
Why
should the Higgs boson exist, and are there any alternatives? In the
underlying equations of the standard model, none of the elementary
particles seems to have mass. In the real world, however, only the
photon and gluon, the carriers of the electromagnetic and strong
nuclear interactions, are massless. All the other elementary particles
are massive, with the W and Z bosons, intermediaries of
the weak nuclear interaction, and the top quark weighing as much as
decent-sized nuclei. The underlying symmetry between the different
particles of the standard model must be broken so that some may acquire
masses.
There are two ways to break the symmetry of
the standard model. The preferred way is to respect the symmetry of the
underlying equations, in which the massless photon and the massive W and Z
bosons appear in the same way, but look for an asymmetric solution,
much as the reader and writer are lopsided solutions of the symmetric
equations of electromagnetism. According to this approach to the
standard model, symmetry is thought to be already broken in the
lowest-energy state, the so-called vacuum. This 'spontaneous' symmetry
breaking is ascribed to a field that permeates all space, taking a
specific value that can be calculated from the underlying equations,
but with a random orientation in the internal 'space' of particles that
breaks the underlying symmetry. This mechanism, which was suggested by
Peter Higgs10 and independently by Robert Brout and François Englert11,
forces some particles, such as the photon, to remain massless, but
gives masses to others in proportion to their coupling to this vacuum
field (Fig. 1).
Figure 1: Picturing the Higgs field.
The
behaviour of physicists in a crowded social event at a conference is an
analogy for the Higgs mechanism, as proposed by David Miller
(University College London). The physicists represent a non-trivial
medium permeating space. In the upper panel, the physicists cluster
around a famous scientist who enters the room, slowing the scientist's
progress. In much the same way, a particle passing through the
Higgs–Brout–Englert field slows down and acquires a mass. In the lower
panel, a rumour propagates. This is an excitation of the medium — the
group of physicists — itself, forming a body with a large mass; this is
analogous to the formation of a Higgs boson. Figure reproduced with
permission from CERN.
In the same way that the
electromagnetic field has a quantum particle associated with it, the
photon, this vacuum field would also have an associated quantum
particle, the Higgs boson. Experiments at LEP seemed at one time to
have found a hint of its existence12. In the end, however, these searches were unsuccessful and told us only that any Higgs boson must weigh at least 114 GeV (ref. 13).
If its mass is less than about 200 GeV, researchers using the Tevatron
may find some evidence for it before the LHC comes into operation14.
The large experiments, ATLAS15 and CMS16, at the LHC will be looking for the Higgs boson in several ways (Fig. 2). The Higgs boson is predicted to be unstable and decay into other particles, such as photons, bottom quarks, tau leptons, W or Z
bosons. It may well be necessary to combine several different decay
modes to uncover a convincing signal. The LHC experiments should be
able to find the Higgs boson even if it weighs as much as 1 TeV, and
there are high expectations that it could be found during the first
couple of years of LHC operation. Its discovery would set the seal on
the success of the standard model.
Figure 2: The Higgs boson at the LHC.
A Higgs (H) boson may be produced by a range of interactions, two examples of which are shown here. The first, a, is through fusion of gluons (g) from the protons in the LHC beams, through a top (t) quark loop; and the second, b, is through a bremsstrahlung process, in which a quark (q) and antiquark 
annihilate to create a W or Z boson, which may then radiate a Higgs. c,
The Higgs itself then decays, and it is these decay products that will
be caught in a detector. The 'branching fraction' or probability of
decay to certain products depends on the (as-yet unknown) mass of the
Higgs particle, which is dominated by decay to a bottom–antibottom
quark pair at low mass, but by decay to pairs of W bosons at high mass.
Higgs or bust?
With
the impending confirmation or refutation of the Higgs hypothesis, many
theorists are getting cold feet. Some are beginning to support
alternative scenarios that go beyond the standard model17.
One popular suggestion is that the Higgs boson might not be an
'elementary' particle in the same sense as the quarks, leptons and the
photon, but instead might be composed of simpler constituents18.
This model would be analogous to the Bardeen–Cooper–Schrieffer (BCS)
theory of superconductivity, in which a photon acquires an effective
mass by interacting with 'Cooper pairs' of electrons. In this analogy,
the W and Z bosons would 'eat' tightly bound pairs of
novel strongly interacting fermions rather than an elementary Higgs
field. It seems rather difficult to reconcile this composite
alternative with the accurate low-energy data from LEP5,
but some enthusiasts are still pursuing this possibility.
Alternatively, it has been suggested that the Higgs boson is indeed
elementary, but is supplemented by some additional physics — for
example, being supersymmetric (discussed later).
The
most radical alternative to the Higgs hypothesis exploits the second
way of breaking the standard model's symmetry. It postulates that,
although the underlying equations are symmetric, their solution is
subject to boundary conditions that break that symmetry. What boundary
would that be, given that space is apparently infinite (or at least
very large compared to the scale of particle physics)? The answer is
that there might be additional, very small dimensions of space with
edges where the symmetry may be broken19.
Such models would have no Higgs boson, and are difficult to reconcile
with the data already acquired that seem to require a relatively light
Higgs boson.
Theorists are amusing themselves
discussing which would be worse: to discover a Higgs boson with exactly
the properties predicted in the standard model or to discover that
there is no Higgs boson. The former would be a vindication of theory,
but would teach us little new. The latter would upset the entire basis
of the standard model. The absence of a Higgs boson would be exciting
for particle physicists, but it might not be so funny to explain to the
politicians who have funded the LHC mainly to discover this particle.
Whichever option nature chooses, the good news is that the LHC will
provide us with a clear-cut experimental answer and end the speculation.
The hierarchy problem
Resolving
the Higgs question will set the seal on the standard model, but, as I
mentioned at the beginning, there are plenty of reasons to expect other
physics beyond the standard model to be discovered (Fig. 3).
Specifically, there are good reasons to expect other discoveries at the
TeV energy scale, within reach of experiments at the LHC. Many would
consider this to be the primary motivation for the leap into the
unknown that the LHC represents.
Figure 3: Physics beyond the TeV scale.
The
standard model has been well tested up to around the 100-GeV mass
scale. The LHC will test beyond this, to the crucial 1,000-GeV level,
the TeV scale, at which hints of new physics, such as supersymmetry and
extra dimensions, may emerge. String theory or grand unified theories
(GUTs) inhabit much higher energy scales, approaching 1019 GeV, which is called the Planck scale.
For example, it is generally
thought that the elementary Higgs boson of the standard model cannot
exist in isolation. Specifically, difficulties arise when one
calculates quantum corrections to the mass of the Higgs boson owing to
the exchanges of virtual particles (see, for example, ref. 20).
Not only are these corrections infinite in the standard model, but, if
the usual procedure of controlling them by cutting the theory off at
some high energy or short distance is adopted, the net result depends
on the square of the cut-off scale. This implies that, if the standard
model were embedded in some more complete theory that kicks in at high
energy — such as a grand unified theory of the particle interactions or
a quantum theory of gravity — the mass of the Higgs boson would be
sensitive to the details of this high-energy theory. This would make it
difficult to understand why the Higgs boson has a (relatively) low
mass. It would also, by extension, make it difficult to explain why the
energy scale of the weak interactions — as reflected in the masses of
the W and Z bosons — is so much smaller than that of unification or quantum gravity.
One
might be tempted simply to wish away this 'hierarchy problem' by
postulating that the underlying parameters of the theory are tuned
finely, so that the net value of the Higgs boson mass obtained after
adding in the quantum corrections is unnaturally small as the result of
some sneaky cancellation. But it would surely be more satisfactory
either to abolish the extreme sensitivity to the quantum corrections or
to cancel them in a systematic manner. Indeed, this has been one of the
reasons for believing that the Higgs boson is composite. If it is, the
Higgs boson would have a finite size, which would cut the pesky quantum
corrections off at some relatively low scale. In this case, the LHC
might uncover a cornucopia of new particles with masses around this
cut-off scale, which should be near 1 TeV. At the very least, the
interactions of the W and Z vector bosons would be modified in an observable way.
The supersymmetric solution
An alternative way to get rid of these quantum corrections is provided by supersymmetry21.
This is an elegant theory that would pair up fermions, such as the
quarks and leptons that make up ordinary matter, with bosons, such as
the photon, gluons, W and Z that carry forces between the matter particles or even the Higgs itself (Fig. 4).
Supersymmetry also seems to be essential for making a consistent
quantum theory of gravity based on string theory (of which more later).
However, these elegant arguments give no clue as to what energies would
be required to observe supersymmetry in nature.
Figure 4: Examples of supersymmetric partners.
Supersymmetry
is a symmetry drawn between fermions (with half-integer spin) and
bosons (with integer spin). It postulates that, for each fermion, there
exists a bosonic partner — such as the supersymmetric electron, or
'selectron', which partners the electron. Similarly, each boson is
thought to have a fermionic superpartner, which for the gluon is the
'gluino'.
The first argument that
supersymmetry might appear near the TeV scale was provided by the
hierarchy problem: in a supersymmetric theory, the quantum corrections
owing to the pairs of virtual fermions and bosons cancel each other
systematically22, and a low-mass Higgs boson no longer seems unnatural23.
The residual quantum corrections to the mass of the Higgs boson would
be small if differences in mass between supersymmetric partner
particles were less than about 1 TeV. Because the fermions and bosons
of the standard model do not pair up with each other in a neat
supersymmetric manner, this theory would require each of the
standard-model particles to be accompanied by an as-yet unseen
supersymmetric partner. It might seem profligate for there to be all
these partners, but at least the hypothesis predicts a 'scornucopia' of
supersymmetric particles that should weigh less than about 1 TeV and
hence could be produced by the LHC15, 16.
In
the wake of this hierarchy argument, at least three other reasons have
surfaced for thinking that supersymmetric particles weigh about 1 TeV.
The first is that these particles would facilitate the unification of
the strong, weak and electromagnetic forces into a simple grand unified
theory24.
Another argument is that a theory with low-energy supersymmetry would
predict that the Higgs boson weighs less than about 150 GeV (ref. 25),
which is precisely the range favoured indirectly by the present data.
The final one is that, in many models, the lightest supersymmetric
particle (LSP) is an ideal candidate for the dark matter advocated by
astrophysicists and cosmologists.
The LSP is ideal because it is stable when a suitable combination of baryon and lepton numbers is conserved26,
as happens in the minimal supersymmetric extension of the standard
model, as well as in simple models of grand unification and neutrino
masses. In this case, LSPs would be left over as relics from early in
the Big Bang, and calculations of their abundance yield a density of
dark matter in the range favoured by astrophysics and cosmology if the
LSP weighs at most a few hundred GeV, probably putting it within reach
of the LHC27.
Supersymmetry
could be a bonanza for the LHC, with many types of supersymmetric
particle being discovered. In many models, the LHC would produce pairs
of gluinos (the supersymmetric partners of the gluons) or squarks (the
supersymmetric partners of the quarks) that would subsequently decay
through various intermediate supersymmetric particles. Finally, each of
these pairs of particles would yield a pair of LSPs that interact only
weakly and hence carry energy away invisibly. In favourable cases, the
masses of several intermediate particles could be reconstructed this
way. It might even be possible to use these measurements to calculate
what the supersymmetric dark-matter density should be, so as to compare
the result with the astrophysical estimates28.
Into extra dimensions?
Postulating
a composite Higgs boson or supersymmetry are not the only strategies
that have been proposed for dealing with the hierarchy problem. Another
suggestion is that there are additional dimensions of space29.
Clearly, space is three-dimensional on the scales that we know so far,
but the idea that there are additional dimensions curled up so small
that they are invisible has been in the air since it was first proposed
by Kaluza and Klein over 80 years ago. This idea has gained ground in
recent years with the realization that string theory predicts the
existence of extra dimensions of space30.
According
to string theory, elementary particles are not idealized points of
euclidean geometry, but are objects extended along one dimension (a
string) or are membranes with more dimensions31.
For the quantum theory of strings to be consistent, particles have to
move in a space with more than the usual three dimensions. Initially,
it was thought that these extra dimensions would be curled up on scales
that might be as small as the Planck length of around 10-33
cm. But more recently, it was realized that at least some of these new
dimensions might be much larger and possibly have consequences
observable at the LHC.
One of the possibilities
offered by these speculations is that gravity is strong when these
extra dimensions appear, possibly at energies close to 1 TeV. Under
this condition, according to some variants of string theory,
microscopic black holes might be produced by the LHC32.
These would be short-lived, decaying rapidly through thermal (Hawking)
radiation. Measurements of this radiation would offer a unique
laboratory window on the mysteries of quantum gravity. The microscopic
black holes would emit energetic photons, leptons, quarks and
neutrinos, providing distinctive experimental signatures. In
particular, the neutrinos they emit would carry away more invisible
energy than LSPs would in the supersymmetric models discussed previously33.
Although
microscopic black holes would be the most dramatic sign of large extra
dimensions, they are not the only sign of such theories that might be
visible at the LHC. If the extra dimensions are curled up on a
sufficiently large scale, the ATLAS and CMS projects might be able to
see Kaluza–Klein excitations of standard-model particles, or even of
the graviton, the mediator particle of gravity. Indeed, the
spectroscopy of some extra-dimensional theories might be as rich as
that of supersymmetry34.
If so, how do we tell which cornucopia the LHC is uncovering? There are
significant differences in the relationship between, for example, the
masses of the partners of quarks and leptons in supersymmetric theories
and in theories with large extra dimensions. Moreover, the spins of the
Kaluza–Klein excitations would be the same as those of their
standard-model progenitors, whereas the spins of the supersymmetric
partners would be different. These underlying differences translate
into characteristic differences in the spectra of decay products in the
two classes of model and into distinctive correlations between them35.
It is amusing that, in some theories with extra dimensions, the lightest Kaluza–Klein particle (LKP) might be stable36,
rather like the LSP in supersymmetric models. In this case, the LKP
would be another candidate for astrophysical dark matter. Thus, there
is more than one way in which LHC physics beyond the standard model
might explain the origin of dark matter: fortunately, the tools seem to
be available for distinguishing between them.
The matter–antimatter conundrum
Will the LHC explain the origin of conventional matter? As was first pointed out by the Russian physicist Andrei Sakharov37,
particle physics can explain the origin of matter in the Universe in
terms of small differences in the properties of matter and antimatter,
such as those discovered in the decays of K and B
mesons. Present experimental data accord well with the
matter–antimatter differences allowed by the standard model. However,
by themselves, these differences in the properties of matter and
antimatter would be insufficient to generate the matter seen in the
Universe. It is possible that the deficit will be explained by new
physics at the TeV scale revealed by the LHC. For example,
supersymmetry allows many more possibilities for differences between
the properties of matter and antimatter than are possible in the
standard model38; some of these differences might explain the amount of matter in the Universe.
This provides one of the motivations for the LHCb experiment39,
which is dedicated to probing the differences between matter and
antimatter, notably looking for discrepancies with the standard model (Box 1).
In particular, LHCb has unique capabilities for probing the decays of
mesons containing both bottom and strange quarks, the constituents of
the B and K mesons probed in other experiments
investigating matter–antimatter differences. There are many other ways
to explore the physics of matter and antimatter, and the ATLAS and CMS
experiments will also contribute to them, in particular by searching
for rare decays of mesons containing bottom quarks.
If
these experiments detect any new particles beyond the standard model at
the TeV scale, questions will immediately arise as to whether this new
physics distinguishes between matter and antimatter, and whether or not
this new physics explains the origin of matter in the Universe. For
example, if the Higgs boson is discovered at the LHC, are its couplings
to matter and antimatter the same? If supersymmetry is discovered at
the LHC, do supersymmetric 'sparticles' and 'antisparticles' behave in
the same way? There are many models in which matter–antimatter
differences in the Higgs or sparticle sector are responsible for the
origin of the matter in the Universe.
Into the future
According
to present plans, the first full-energy collisions of the LHC will take
place in 2008, although it will take some time for the accelerator to
build up to its designed nominal collision rate. There are hopes,
however, that in its first couple of years of operation, it will
already start to provide crucial information on physics beyond the
standard model, for example by discovering the Higgs boson — or other
new particles such as those predicted by supersymmetry, if they are not
too heavy40.
Continued running of the LHC at its nominal luminosity would enable
many properties of the Higgs boson to be verified, for example by
providing measurements of its couplings to some other particles and
checking whether these are proportional to the particles' masses. This
period should also enable the properties of any other newly discovered
particles to be checked, such as establishing whether their spins are
the same as those of their standard-model counterparts or are different.
What
might be possible using the LHC after these planned phases of
exploitation? One possibility is to add new components to the existing
ATLAS and CMS detectors that would provide new ways to study the Higgs
boson. For example, new components close to the beams several hundred
metres from the interaction points might be able to detect rare
proton–proton collisions that produce nothing except a single isolated
Higgs boson41.
Another possibility is that supersymmetric or other new particles might
show up in unexpected ways. For example, in some supersymmetric
scenarios there would be a metastable charged particle that would have
quite distinctive experimental signatures42, and it might be interesting to devise new detectors to explore this possibility.
It
might also be possible to increase the LHC collision rate significantly
beyond the nominal value. This possibility would be particularly
interesting if, for example, the initial runs of the LHC discover new
physics with a very low production rate, perhaps because it has a high
energy threshold. Increasing the LHC collision rate might be possible
by redesigning the collision points using new magnet technologies; it
would also require replacing at least some of CERN's lower-energy
accelerators, such as the low-energy linear proton accelerator and the
Proton Synchrotron, so as to feed more intense beams into the LHC43.
Technical options for increasing the LHC collision rate are now being
evaluated, so that they can be considered when the first experimental
results from the initial LHC runs become available, some time around
2010.
Exploitation of the LHC and the study of
possible upgrade options are among the highest priorities for European
particle physics and were decided upon at a special meeting of the CERN
Council in Lisbon in July 2006 (ref. 44).
Possible future accelerators were also considered, such as a linear
electron–positron collider or a neutrino factory. The priorities for
these options will surely depend on the nature and energy scale of
whatever new physics beyond the standard model the LHC reveals, as well
as on developments in other areas such as neutrino physics. A central
element in the European strategy for particle physics is the need to
review advances in particle physics in the coming years, and in
particular to review the implications of any LHC discoveries at the end
of this decade.
Particle physics stands on the brink
of a new era. Research using the LHC will make the first exploration of
physics in the TeV energy range. There are good reasons to hope that
the LHC will find new physics beyond the standard model, but no
guarantees. The most one can say for now is that the LHC has the
potential to revolutionize particle physics, and that in a few years'
time we should know what course this revolution will take. Will there
be a Higgs boson, or not? Will space reveal new properties at small
distances, such as extra dimensions or supersymmetry? Will experiments
at the LHC cast light on some fundamental cosmological questions, such
as the origin of matter or the nature of dark matter? Whatever the
answers to these questions might be or whatever surprises the LHC might
spring, it will surely set the agenda for the next steps in particle
physics.
Top of page
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