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The Belle collaboration at the KEK laboratory in Japan has discovered a new sub-atomic particle which it is calling the "X(3872)". The particle does not fit into any known particle scheme and theorists are speculating that it might be a hitherto unseen type of meson that contains four quarks (arxiv.org/abs/hep-ex/0309032; Phys. Rev. Lett. to be published). The discovery has been confirmed by the CDF collaboration at Fermilab in the US, where the new particle is being called the "mystery meson". Mesons are particles that contain a quark and an antiquark that are held together by the strong nuclear force. Since...

In part 2 of the interview, Astronomer Royal, Sir Martin Rees discusses the limits to our knowledge of what might have preceded the big bang. Everyone asks the question: what was 'there' the instant before everything came to be?, but the question may not go as deep as the answers it spawns. Helen Matsos: Last year the big "science event" was measuring the cosmic microwave background and dating the big bang to 13.8 billion years ago, within an 8 to 10 percent margin of error. Can you give us some idea of the boundaries of the big bang -- what...

Lisa Randall has become a star in the rarefied world of high-energy physics, and her theory about a “fifth dimension” has caught the imagination of the general public too. That doesn’t mean she still isn’t shy and a little nervous about all the hoopla. “I really like that my work is getting more people interested in science,” says the 43-year old Harvard physicist. “And while it can get a little nerve-wracking dealing with all the attention, I really enjoy speaking to the public and answering questions.” Randall seems constantly in motion. She seldom sits still, and says her mind brims...

The European Space Agency is considering a unique experiment that could explain strange gravitational phenomena in the outer solar system. Since 1998 astronomers have known that the space probes Pioneer 10 and Pioneer 11 are following trajectories that cannot be explained by conventional physics. Launched in 1972 and 1973, respectively, to explore the outer planets, the Pioneer craft are now at the edge of the solar system, with Pioneer 10 being some 86 astronomical units (about 13 billion kilometres) from the Sun. But they are not quite where they should be, based on the gravitational pull of the known bodies...

SEARCH RESULTS Evidence for Universe Expansion FoundEvidence for Universe Expansion FoundScientists: Find explains how universe formedCold War gamma-ray mystery solved in a flashU.S. spacecraft set to study cosmic bursts Front page March 17, 2006, 12:51AMOldest light shows universe grew fast, researchers sayFirst stars arose 400 million years after big bang, not 200 million years, as once thought By DENNIS O'BRIEN Baltimore Sun Scientists examining the oldest light in the universe say they've found clear evidence that matter expanded at an almost inconceivable rate after the big bang, creating conditions that led to the formation of the first stars.Light from...

It was the summer of 1998, recalls Harvard University physicist Lisa Randall, when extra dimensions finally pulled her in. Extra dimensions -- beyond the four we encounter every day (three of space plus one of time) -- have been an ingredient of theoretical physics for decades: mathematician Theodor Kaluza proposed a fifth in 1919, string theory requires 10 of them, M-theory needs 11. But Randall hadn't much use for them, she says, until that summer when she decided they might be helpful to supersymmetry, one of the conundrums she was pondering. Randall contacted Raman Sundrum, a Boston University postdoctoral student...

Gamma-ray bursts could be the signature of ultradense stars. This X-ray image shows the 3C58 pulsar, the remnant of a supernova noted on Earth in AD 1181, which astronomers suspect may be a quark star. It lies about 10,000 light years from Earth.© NASA/SAO/CXC/P.Slane et al. Intense flashes of gamma rays in far-off galaxies might be produced by a bizarre kind of star, consisting of phenomenally dense material in which the particles that make up atomic nuclei have fallen apart. Two astrophysicists have proposed that gamma-ray (gamma-ray) bursts, whose origins have foxed astronomers for decades, might be the signatures of...

In what is widely regarded as the most important scientific discovery of 1998, researchers turned their telescopes to measure the rate at which cosmic expansion was decelerating and instead saw that it was accelerating. They have been gripping the steering wheel very tightly ever since. As deeply mysterious as acceleration is, if you just accept it without trying to fathom its cause, it solves all kinds of problems. Before 1998, cosmologists had been troubled by discrepancies in the age, density and clumpiness of the universe. Acceleration made everything click together. It is one of the conceptual keys, along with other...

Scientists are closer than ever to balancing the checkbook of cosmic matter. This is because two recent independent measurements of normal matter in the universe are in agreement. The results further strengthen the case for the Big Bang theory and for the nature of the universe as astronomers understand it today. The universe contains normal atomic matter, what makes you, your dog, the stars, and everything in between. Normal matter is what Carl Sagan was talking about when he said we are all star-stuff. But in addition to star-stuff, there is invisible dark matter that is known only because the ...

A GROUP of astronomers and cosmologists has warned that the laws thought to govern the universe, including Albert Einstein's theory of relativity, must be rewritten. The group, which includes Professor Stephen Hawking and Sir Martin Rees, the astronomer royal, say such laws may only work for our universe but not in others that are now also thought to exist. "It is becoming increasingly likely that the rules we had thought were fundamental through time and space are actually just bylaws for our bit of it," said Rees, whose new book, Our Cosmic Habitat, is published next month. "Creation is ...

The genius of Albert Einstein, who added a "cosmological constant" to his equation for the expansion of the universe but later retracted it, may be vindicated by new research published today in the journal Astronomy and Astrophysics. The enigmatic "dark energy" that drives the acceleration of the Universe behaves just like Einstein's famed cosmological constant, according to the Supernova Legacy Survey (SNLS), an international team of researchers in France and Toronto and Victoria in Canada, collaborating with large telescope observers in Oxford, Caltech and Berkeley. Their observations reveal that the dark energy behaves like Einstein's cosmological constant to a precision...

WASHINGTON, D.C. - Scientists may not have to go over to the dark side to explain the fate of the universe.The theory that the accelerated expansion of the universe is caused by mysterious "dark energy" is being challenged by New York University physicist Georgi Dvali. He thinks there's just a gravity leak.Scientists have known since the 1920s that the universe is expanding. In the late 1990s, they realized that it is expanding at an ever-increasing pace. At a loss to explain the stunning discovery, cosmologists blamed it on dark energy, a newly coined term to describe the mysterious antigravity force...

Grisha Perelman, where are you? Three years ago, a Russian mathematician by the name of Grigory Perelman, a k a Grisha, in St. Petersburg, announced that he had solved a famous and intractable mathematical problem, known as the Poincaré conjecture, about the nature of space. After posting a few short papers on the Internet and making a whirlwind lecture tour of the United States, Dr. Perelman disappeared back into the Russian woods in the spring of 2003, leaving the world’s mathematicians to pick up the pieces and decide if he was right. Now they say they have finished his work,...

Space and time are pervasive in our everyday experience, and yet it is hard to say exactly what they are. They resist definition in terms other than themselves. Moreover, they have various subtle and elusive properties, with which science continues to grapple. Relativity and quantum mechanics, the physics breakthroughs of the 20th century, revolutionized scientific thinking about these subjects. And this revolution has not played itself out, since cutting-edge physics today involves further radical rethinking of time and space. The Fabric of the Cosmos: Space, Time, and the Texture of Reality, by Brian Greene (Knopf, $28.95), is an excellent guide...

Welcome to the fourth dimension. And the fifth, and the sixth. A team of astrophysicists claims to have identified evidence that space is six-dimensional. Joseph Silk of the University of Oxford, UK, and his co-workers say that these extra spatial dimensions can be inferred from the perplexing behaviour of dark matter. This mysterious stuff cannot be seen, but its presence in galaxies is betrayed by the gravitational tug that it exerts on visible stars. Silk and his colleagues looked at how dark matter behaves differently in small galaxies and large clusters of galaxies. In the smaller ones, dark matter seems...

More than 60 years ago, G. H. Hardy, an English mathematician besotted with abstraction, wrote, " `Imaginary' universes are so much more beautiful than this stupidly constructed `real' one." Were Hardy around today, he'd find plenty of company. From astronomers peering out into space to particle physicists inspecting atomic innards, the more scientists study the universe, the more preposterous, random, and, yes, ugly it becomes. But hold it. How can the universe be thought ugly? This realm of wheeling galaxies whose stars explode gloriously to seed space with the building blocks of life? A cosmos that bore at least one...

December 7, 2004 Shiing-Shen Chern, 93, Innovator in New Geometry, Is Dead By KENNETH CHANG r. Shiing-Shen Chern, a mathematician whose seemingly purely abstract discoveries about the twistings of geometric surfaces have found wide use in physics and mathematics, died Friday at his home in Tianjin, China. He was 93.Dr. Chern also helped set up three mathematics institutes, two in China and one at the University of California, Berkeley. Nankai University, where Dr. Chern established an institute in 1985, reported his death."He's a towering figure in 20th-century mathematics," said Dr. Calvin C. Moore, a professor of mathematics at the...

Physicists have created the state of matter thought to have filled the Universe just a few microseconds after the big bang and found it to be different from what they were expecting. Instead of a gas, it is more like a liquid. Understanding why it is a liquid should take physicists a step closer to explaining the earliest moments of our Universe. Not just any old liquid, either. Its collective movement is rather like the way a school of fish swims 'as one' and is a sign that the fluid possesses an extremely low viscosity, making it what physicists call...

Public release date: 26-Oct-2004 [ Print This Article | Close This Window ] Contact: Steve Koppes skoppes@uchicago.edu 773-702-8366 University of Chicago Scientists zero in on why time flows in one direction The big bang could be a normal event in the natural evolution of the universe that will happen repeatedly over incredibly vast time scales as the universe expands, empties out and cools off, according to two University of Chicago physicists. "We like to say that the big bang is nothing special in the history of our universe," said Sean Carroll, an Assistant Professor in Physics at the University of...