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Summary - (Apr 29, 2005) Gravitational lensing happens when the gravity of a relatively close galaxy acts as a telescope lens to focus the light from a more distant galaxy. It allows astronomers to see distant objects they could never have a hope of observing with current instruments, essentially looking back to moments after the Big Bang (cosmically speaking). The galaxies are never perfectly lined up, though, and the "natural telescope" is a bit blurry. But now astronomer Remi Cabanac has found one of the most complete lenses ever discovered: a near perfect Einstein Ring, magnifying a distant galaxy with...

If the universe contains more than three spatial dimensions, as many physicists believe, our current laws of gravity should break down at small distances. Nothing seems more certain than the "fact" that there are three dimensions of space. But can we be sure that there are only three dimensions? Imagine a tightrope walker balancing on a cable high above the ground. To the tightrope walker the cable is effectively a 1D object, because he only needs one coordinate to specify his position as he walks back and forth. But an ant, for instance, sees the cable as a 2D object,...

n a kind of belated birthday present to Albert Einstein, whose theory of relativity is 100 years old this year, astronomers say they have confirmed an essential but previously unconfirmed prediction of general relativity, namely that the entire universe can act as a magnifying lens. The light from distant quasars, enigmatic and violent galaxy-birthing events on the shores of time, some 10 billion light-years away, has been magnified by the gravitational force of lumps and irregularities in the structure of the nearby cosmos. So the quasars appear slightly brighter in telescopes than they actually are, according to a multinational team...

A hundred years ago, Albert Einstein published his theory of relativity. On this occasion, Euronews' Space magazine plunges into the subject of gravitational waves and features the joint ESA-NASA "LISA" mission which hopes to detect them in space. The existence of gravitational waves stems from Einstein's postulates. When very massive bodies are disturbed, they radiate waves or ripples that travel through space. When these waves hit an object, this will make minute movements as a consequence of the deformation of the space-time texture in which it is at rest. The Laser Interferometer Space Antenna (LISA) mission, whose launch is envisaged...

Galaxy Observations Show No Change In Fundamental Physical Constant The results are being reported today (Monday, April 18) at the annual meeting of the American Physical Society (APS) by astronomer Jeffrey Newman, a Hubble Fellow at Lawrence Berkeley National Laboratory representing DEEP2, a collaboration led by the University of California, Berkeley, and UC Santa Cruz. Newman is presenting the data and an update on the DEEP2 project at a 1 p.m. EDT press conference at the Marriott Waterside Hotel in Tampa, Fla. The fine structure constant, one of a handful of pure numbers that occupy a central role in physics,...

The concept of time is self-evident. An hour consists of a certain number of minutes, a day of hours and a year of days. But we rarely think about the fundamental nature of time. Time is passing non-stop, and we follow it with clocks and calendars. Yet we cannot study it with a microscope or experiment with it. And it still keeps passing. We just cannot say what exactly happens when time passes. Time is represented through change, such as the circular motion of the moon around the earth. The passing of time is indeed closely connected to the concept...

In mid–February, I participated in a NASA Science Update press briefing that presented gamma–ray and radio observations of a flaring neutron star. A neutron star is a solar–mass worth of mundane and exotic nuclei and fundamental particles trapped by gravity at supranuclear densities, exhibiting superfluidity and superconductivity. The star is encased within a solid crust, a liquid ocean, a gaseous atmosphere, and a relativistic plasma magnetosphere capable of inducing zettavolt electromotive forces and radiating intense, coherent emission. Neutron stars are used to test general relativity and to search for gravitational radiation. The neutron star in question is also a “magnetar,”...

Black holes are staples of science fiction and many think astronomers have observed them indirectly. But according to a physicist at the Lawrence Livermore National Laboratory in California, these awesome breaches in space-time do not and indeed cannot exist. Over the past few years, observations of the motions of galaxies have shown that some 70% the Universe seems to be composed of a strange 'dark energy' that is driving the Universe's accelerating expansion. George Chapline thinks that the collapse of the massive stars, which was long believed to generate black holes, actually leads to the formation of stars that contain...

An Open Letter to the Scientific Community cosmologystatement.org(Published in New Scientist, May 22, 2004)The big bang today relies on a growing number of hypothetical entities, things that we have never observed-- inflation, dark matter and dark energy are the most prominent examples. Without them, there would be a fatal contradiction between the observations made by astronomers and the predictions of the big bang theory. In no other field of physics would this continual recourse to new hypothetical objects be accepted as a way of bridging the gap between theory and observation. It would, at the least, raise serious questions...

For more than 30 years, astrophysicists have believed that black holes can swallow nearby matter and release a tremendous amount of energy as a result. Until recently, however, the mechanisms that bring matter close to black holes have been poorly understood, leaving researchers puzzled about many of the details of the process. Now, however, computer simulations of black holes developed by researchers, including two at The Johns Hopkins University, are answering some of those questions and challenging many commonly held assumptions about the nature of this enigmatic phenomenon. "Only recently have members of the research team -- John Hawley and...

Are We Alone? A Tête-à-Tête Between Neil deGrasse Tyson and Peter Ward Despite decades of concerted effort by radio astronomers working on the project known as SETI, the Search for Extraterrestrial Intelligence, we've had no sign of beings elsewhere in the universe that match or exceed us in smarts. That's just one of many pieces of evidence that paleontologist Peter Ward, coauthor of Rare Earth: Why Complex Life is Uncommon in the Universe, points to when claiming that intelligent life beyond Earth must be exceedingly rare. Since many other scientists believe advanced life is common out there—Carl Sagan estimated...

Black holes may define the perfect fluid, suggests a study of black holes that only exist in a theoretical 10-dimensional space. The finding may have spawned a new universal law in physics, which puts constraints on the way fluids behave in the real world. Dam Thanh Son from the University of Washington, US, and his colleagues used string theory to model a 10-dimensional black hole as a liquid. String theory tries to explain fundamental properties of the universe by predicting that seven more spatial dimensions exist on top of the known three. While the concept is currently unproven as a...

ROME (Reuters) - A small group of physicists are battling what they see as the cosmological equivalent to the bogeyman: an enormous dark force, that nobody has ever seen, driving galaxies apart. Conventional wisdom holds that the mysterious force, called "dark energy," may make up 70 percent of the universe, and could be the determining factor in whether it is eventually destroyed billions of years from now. But Italian and American cosmologists are offering a controversial alternative to explain the accelerating expansion of the universe. They say it's not dark energy, but an overlooked after-effect of the "Big Bang" --...

The Good and Bad of String Theory The most celebrated theory in modern physics faces increasing attacks from skeptics who fear it has lured a generation of researchers down an intellectual dead end. In its original, simplified form, circa the mid-1980s, string theory held that reality consists of infinitesimally small, wiggling objects called strings, which vibrate in ways that yield the different subatomic particles that comprise the cosmos. Advocates claimed that string theory would smooth out the conflicts between Einsteinian relativity and quantum mechanics and the result would be a unifying "theory of everything," which could explain everything from...

Astronomers have found distant red galaxies—very massive and very old—in the universe when it was only 2.5 billion years post Big Bang. “Previous observations suggested that the universe at this age was home to young, small clumps of galaxies long before they merged into massive structures we see today,” remarked Carnegie Observatories Ivo Labbé, who led the group of astronomers in the study. [Members of the research project are listed at the end of the original article.] “We are really amazed — these are the earliest, oldest galaxies found to date. Their existence was not predicted by theory and it...

Giant space-time ripples may cause cosmic expansion* 17:43 18 March 2005 * NewScientist.com news service * Maggie McKee Dark energy is not necessary to explain the accelerating expansion of the universe observed by astronomers, suggest controversial new calculations. Instead, gigantic ripples in space-time - larger than the observable universe - may be the cause. Astronomers have known since the 1920s that space itself has been expanding since the big bang about 14 billion years ago. But in 1998, they discovered the expansion must have sped up about a billion years ago, based on observations of supernovae that appeared farther away...

Why is the universe expanding at an accelerating rate, spreading its contents over ever greater dimensions of space? An original solution to this puzzle, certainly the most fascinating question in modern cosmology, was put forward by four theoretical physicists, Edward W. Kolb of the U.S. Department of Energy's Fermi National Accelerator Laboratory, Chicago (USA): Sabino Matarrese of the University of Padova; Alessio Notari from the University of Montreal (Canada); and Antonio Riotto of INFN (Istituto Nazionale di Fisica Nucleare) of Padova (Italy). Their study was submitted yesterday to the journal Physical Review Letters. Over the last hundred years, the expansion...

An international team of astronomers using the world's largest X-ray and optical telescopes have spotted the most distant massive object ever detected, a cluster of galaxies 9 billion light years distant from Earth. The cluster of galaxies is so far away that the light detected by the team is much older than the Earth itself. The galaxy cluster, if it is even still there, would be at least 11 billion years old now. "By capturing this ancient, 9-billion-year-old light, we have a snapshot of the universe at a youthful age of less than 5 billion years, which is about 1/3...

Could two lookalike galaxies, barely a whisker apart in the night sky, herald a revolution in our understanding of fundamental physics? Some physicists believe that the two galaxies are the same - its image has been split into two, they maintain, by a "cosmic string"; a San Andreas Fault in the very fabric of space and time. If this interpretation is correct, then CSL-1 - the name of the curious double galaxy - is the first concrete evidence for "superstring theory": the best candidate for a "theory of everything", which attempts to encapsulate all the phenomena of nature in one...

Does Science Point to God? Part II: The Christian Critics By Benjamin D. WikerAuthor's note: In the first part of this article, "Does Science Point to God? The Intelligent Design Revolution" (April 2003), I focused on Intelligent Design (ID) as a scientific revolution. In this article, I will get at the importance of the ID movement from a different angle. What happens if we just ignore the ID challenge to evolutionary theory, accept the status quo, and accommodate ourselves to Darwinism? As we shall see, the price of indiscriminate accommodationism to Darwinism is rather high indeed.No scientific theory should have...