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  • An international race is picking up speed, to see our universe for what it really is

  • and how it came to be.

  • According to the

  • standard theory that describes the origins of the universe, its early moments were marked

  • by the explosive contact between subatomic particles of opposite charge.

  • Scientists are now focusing their most powerful technologies on an effort to figure out exactly

  • what happened.

  • Our understanding of cosmic history hangs on the question: how did matter as we know

  • it survive? And what happened to its birth twin, its opposite, a mysterious substance

  • known as antimatter?

  • A crew of astronauts is making its way to a launch pad at the Kennedy Space Center in

  • Florida. They'll enter the space shuttle Endeavor for the 134th, and second to the last, flight

  • of the space shuttle.

  • Little noticed in the publicity surrounding the close of this storied program is the cargo

  • bolted into Endeavor's hold.

  • It's a science instrument that some hope will become one of the most important scientific

  • contributions of human space flight.

  • It's a kind of telescope, though it will not return dazzling images of cosmic realms long

  • hidden from view, the distant corners of the universe, or the hidden structure of black

  • holes and exploding stars.

  • Unlike the great observatories that were launched aboard the shuttle, it was not named for a

  • famous astronomer, like Hubble, or the Chandra X-ray observatory.

  • The instrument, called the Alpha Magnetic Spectrometer, or AMS, is the brainchild of

  • this man, Samuel Ting, from Massachusetts Institute of Technology.

  • At the heart of the AMS is a large superconducting magnet designed to operate in the pristine

  • environment of space.

  • With its intensive power requirements, the final version was attached to the international

  • space station.

  • The promise surrounding this device is that it will enable scientists to look at the universe

  • in a completely new way.

  • Most telescopes are designed to capture photons, so-called neutral particles reflected or emitted

  • by objects such as stars or galaxies.

  • AMS will capture something different: exotic particles and atoms that are endowed with

  • an electrical charge. Among these are a theoretical dark matter particle called a neutralino.

  • Then there are the strangelets, a type of quark that could amount to a whole new form

  • of matter.

  • The instrument is tuned to capture "cosmic rays" at high energy hurled out by supernova

  • explosions or the turbulent regions surrounding black holes.

  • And there are high hopes that it will capture particles of antimatter from a very early

  • time that remains shrouded in mystery.

  • The chain of events that gave rise to the universe is described by what's known as the

  • Standard model. It's a theory in the scientific sense, in that it combines a body of observations,

  • experimental evidence, and mathematical models into a consistent overall picture. But this

  • picture is not necessarily complete.

  • The universe began hot. After about a billionth of a second, it had cooled down enough for

  • fundamental particles to emerge in pairs of opposite charge, known as quarks and antiquarks.

  • After that came leptons and antileptons, such as electrons and positrons.

  • These pairs began annihilating each other.

  • Most quark pairs were gone by the time the universe was a second old, with most leptons

  • gone a few seconds later.

  • When the dust settled, so to speak, a tiny amount of matter, about one particle in a

  • billion, managed to survive the mass annihilation.

  • That tiny amount went on to form the universe we can know - all the light emitting gas,

  • dust, stars, galaxies, and planets.

  • To be sure, antimatter does exist in our universe today. The Fermi Gamma Ray Space Telescope

  • spotted a giant plume of antimatter extending out from the center of our galaxy, most likely

  • created by the acceleration of particles around a supermassive black hole.

  • The same telescope picked up signs of antimatter created by lightning strikes in giant thunderstorms

  • in Earth's atmosphere.

  • A European cosmic ray satellite called Pamela detected a huge store of antiprotons in orbit

  • around the earth created by high-energy particles striking the upper atmosphere, then held there

  • by magnetic fields that ring the planet.

  • Scientists have long known how to create antimatter artificially in physics labs - in the superhot

  • environments created by crashing atoms together at nearly the speed of light.

  • Here is one of the biggest and most enduring mysteries in science: why do we live in a

  • matter-dominated universe? What process caused matter to survive and antimatter to all but

  • disappear?

  • One possibility: that large amounts of antimatter have survived down the eons alongside matter.

  • That was the view of the German-born physicist Arthur Schuster, who appears to have coined

  • the term "antimatter" in 1898. He imagined that its opposite charge would allow it to

  • act as a counter to gravity:

  • "Large tracts of space," he wrote, "might thus be filled unknown to us with a substance

  • in which gravity is practically non-existent, until by some accidental cause, such as a

  • meteorite flying through it, unstable equilibrium is established, the matter collecting on one

  • side, the antimatter on the other until two worlds are formed separating from each other,

  • never to unite again."

  • The issue gathered dust until 1928, when a young physicist, Paul Dirac, wrote equations

  • that predicted the existence of antimatter.

  • Dirac showed that every type of particle has a twin, exactly identical but of opposite

  • charge.

  • So for every proton, there's an antiproton. For every electron, there's a positron. For

  • every neutron, an antineutron. Within them, are quarks and their twins, the antiquarks.

  • As Dirac saw it, the electron and the positron are mirror images of each other. With all

  • the same properties, they would behave in exactly the same way whether in realms of

  • matter or antimatter.

  • In his Nobel Prize lecture in 1933, Dirac pondered a larger reality for antimatter.

  • "If we accept," he said, "the view of complete symmetry between positive and negative electric

  • charge so far as concerns the fundamental laws of Nature, we must regard it rather as

  • an accident that the Earth (and presumably the whole solar system), contains a preponderance

  • of negative electrons and positive protons. It is quite possible that for some of the

  • stars it is the other way about, these stars being built up mainly of positrons and negative

  • protons."

  • Just the year before, the physicist Carl Anderson had confirmed the existence of antimatter

  • by shooting gamma rays at atoms, creating electron-positron pairs.

  • It became clear, though, that ours is a matter universe. The Apollo astronauts went to the

  • moon and back, never once getting annihilated.

  • Solar cosmic rays proved to be matter, not antimatter.

  • Traveling to every corner of the solar system, our probes have not encountered any objects

  • made of antimatter.

  • Cosmic rays from the Milky Way are overwhelmingly matter.

  • If there any large concentrations in nearby galaxies or galaxy clusters, we should see

  • gamma rays produced when particles and antiparticles found each other.

  • It stands to reason, too, that when the universe was more tightly packed, that it would have

  • experienced an "annihilation catastrophe" that cleared the universe of large chunks

  • of the stuff.

  • Unless antimatter somehow became separated from its twin at birth and exists beyond our

  • field of view, scientists are left to wonder: why do we live in a matter-dominated universe?

  • Dirac's "symmetrical" view of matter and antimatter, which saw them as equivalent, collapsed three

  • decades later in 1964. The American physicists James Cronin and Val Fitch examined the decay

  • of a particle called a kaon to its antiparticle twin.

  • They found that the transformation back to normal matter did not occur with the same

  • probability. That would suggest there must be small differences in the physical laws

  • that govern matter and antimatter.

  • To find out exactly what makes them different, or asymmetrical, would be a big step toward

  • understanding how our universe took the shape that it did.

  • That's why physicists are hot on the trail of antimatter with new technologies designed

  • to give them a closer look at this strange substance in nature and in the lab.

  • What if there is some antimatter out there, escapees from the mass annihilation of the

  • big bang still fleeing through the emptiness of space?

  • The crew of Endeavour placed the AMS instrument on its perch on the international space station

  • in May 2011. Since then, scientists have been combing the data for the signatures of antimatter

  • particles striking its detector.

  • If they manage to detect heavier elements such as antihelium or anticarbon, that would

  • point to concentrations of antimatter in space large enough to have formed stars, where those

  • elements are created, and suggest that symmetry may not have been broken after all.

  • Such heavier antiatoms can exist. At Brookhaven National Lab in New York, scientists recently

  • smashed gold atoms together at nearly the speed of light. From about a billion individual

  • collisions, its detectors recorded the presence of 18 antihelium atoms - atoms with two antiprotons

  • and two antineutrons.

  • The explosive potential of antimatter in this universe has long animated the voyages of

  • science fiction. It's the fuel of choice for getting beyond our solar system, and out to

  • the stars.

  • Just to get into orbit, the space shuttle had to be loaded up with some 15 times its

  • weight in conventional rocket fuel. The energy contained in antimatter is orders of magnitude

  • greater. In fact, it would take just a coin-sized portion to propel the shuttle into orbit.

  • Because antimatter is so volatile in our matter-filled universe, the challenge for scientists is

  • first to create it, then to hold it for enough time to study it, before it simply vanishes.

  • Even as the shuttle Endeavour glided onto land for the last time, AMS scientists were

  • beginning to filter through the rush of charged particles in space.

  • Meanwhile, scientists on the ground were beginning their own intensive efforts to corral antimatter

  • in their labs.

  • To really find out what happened in that early epoch of annihilation, scientists will have

  • to understand more about the properties and behavior of antimatter.

  • They are trying to do this at the giant European physics lab, CERN. In a little known corner,

  • the AntiProton Deceleration Lab, a group of scientists is showing that you can actually

  • trap and hold antimatter long enough to study it.

  • The antiprotons from the antiproton decelerator, that's the machine we need here at Cern, come

  • down this pipe right here. And they come into our apparatus, which is inside this large

  • magnet. This is a very strong magnetic field to help to confine the charged that make antihydrogen.

  • Inside the Alpha chamber, the magnetic field holds the particles in place and isolates

  • them from one another.

  • An electric field separates the electrons and positrons. They are then carefully brought

  • into contact. When two positrons collide, one falls into orbit around an antiproton,

  • forming antihydrogen.

  • Then, the molecule is trapped by magnetic fields, like a marble rolling around in a

  • bathtub. Now remove the bathtub, the magnetic fields. The antimolecule smacks up against

  • the wall of the detector and annihilates, emitting a shower of particles.

  • So what we do is hold onto them for a thousand seconds, then release them to make sure they

  • are there. That's how you do this measurement.

  • That one thousand seconds, almost 17 minutes, is a major accomplishment.

  • On the atomic life scale, a thousand seconds is forever. Things on the atomic life scale

  • are measured in nanoseconds or smaller perhaps. So this is forever for an atom to be trapped.

  • The next step is to hold onto it, see how long can we keep it around so that we can