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When it comes to nursing articles, Sam suggest that parents should ______.
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But much of the wobble has been fixed, thanks to a satellite known as the Wilkinson Microwave Anisotropy Probe, or W. MAP. Since July 2001, WMAP has been orbiting in deep space, more than a million kilometers from Earth, studying the most ancient light in existence. And in a dramatic reminder that important space science is almost always done by machines, not fragile humans, it reported a series of precision measurements that will finally put cosmology on a firm foundation.
What the satellite found, says Princeton University's David Spergel, a theorist on the WMAP team, "is that the universe can be explained with five numbers. "First, the cosmos is 13. 7 billion years old, give or take a negligible couple of hundred million years. Second, the first stars turned on just 200 million years after the Big Bang, Finally, the universe is made of three things in the following proportions: 4% ordinary atoms; 23% "dark matter," whose nature is still unknown; and 73% "dark energy," the equally mysterious force whose antigravity effect is speeding up the cosmic expansion. "This," says astrophysicist John Bahcall, of the Institute for Advanced Study in Princeton, New Jersey, "is a rite of passage for cosmology, from speculation to precision science."
WMAP learned this and more by scrutinizing the faint whisper of microwaves left over from the Big Bang. Hidden in that radiation are patterns of warmer and cooler spots, marking places where matter was a little more or less dense than average--spots that would eventually evolve into the clusters of galaxies and empty spaces that we see today. These patterns were first detected in crude form. by the Cosmic Background Explorer satellite in 1992, But without enough detail for much to be said about them. But with a resolution some 40 times as sharp as COBE's, WMAP has plenty to say. "It's a lot like matching fingerprints," says Spergel. "We ran computer simulations based on many different values for all of the numbers, generated patterns for each and found the one that best matched what we actually saw."
WMAP also confirmed what earlier experiments had suggested about a basic characteristic of the milverse; the geometry of space-time, in the Einsteinian sense, is flat. That's consistent with a theory called inflation, which posits that the cosmos underwent a period of turbocharged expansion before it was a second old. "I have to admit," says Bahcall, "that I was skeptical of the picture theorists had put together. Inflation, dark matter, dark energy--it's all pretty implausible. But this implausible, crazy universe has now been confirmed with exquisite detail."
That's not to say that WMAP has answered every question. Nobody knows what dark matter and dark energy are, and the theory of inflation, while strengthened, is far from proved. Beyond that, there are some strange measurements in WMAP's data that might be mere statistical flukes or might point to some major monkey wrench that could still throw cosmology into turmoil. "We should know better after we get in more data," says Charles Bennett of the Goddard Space Flight Venter, who is the V team leader.
But cosmologists won't be sitting around waiting. "You're going to see a thousand papers based on these results," says Tegmark, who is already working on several. "It's an exciting time to be in this field"
It can be inferred from the first paragraph that cosmologists ______.
Slobodan Davidovic was given a 15-year prison sentence because ______.
The companies are lured by a booming market in which capitalist competition is still scarce. The num her of university students is expected to double in the next 25 years to 170 million worldwide. Demand greatly exceeds supply, because the 1990s saw massive global investment in primary and secondary schools, but not in universities. The number of children enrolled in primary or secondary schools rose by 18 percent around the world--more than twice the rate of increase in any previous decade. Now these kids are often graduating from high school to find no openings in national universities, which nevertheless don't welcome for-profit competition. The Brazilian university teachers' union warned that foreign corporations would turn higher education into "a diploma industry". Critics raised the specter of declining quality and a loss of Brazil's "sovereign control" over education.
For-profit universities met with similar suspicion when they first opened in the United States. By the 1980s they were regularly accused of offering substandard education and had to fight for acceptance and respect. Lately, they have flourished by catering to older students who aren't looking for keg parties, just a shortcut to a better career. For-profit colleges now attract 8 percent of four-year students in the United States, up from 3 percent a decade ago. By cutting out frills, including sports teams, student centers and summer vacation, these schools can operate with profit margins of 20 to 30 percent.
In some countries, the American companies operate as they do at home. Apollo found an easy fit in Brazil, where few universities have dorms, students often take off time between high school and college, and there's no summer vacation--just two breaks in July and December. In other Latin countries, Sylvan has taken a different approach, buying traditional residential colleges like the Universidad del Valle de Mexico (UVM). It has boosted enrollment by adding and heavily advertising courses in career-track fields like business and engineering, and adding no-frills satellite campuses. Sensitive to the potential hostility against foreign buyers, Sylvan keeps original school names, adding its own brand, Sylvan International Universities, to publicity materials, and keeps tuition in line with local private schools.
Most of the schools that Sylvan has purchased were managed by for-profits to begin with, including the prestigious Les Roches Hotel Management School in Switzerland. But in general, Says Urdan, Sylvan's targets "have not been run with world-class business practices. They're not distressed, but there's an opportunity for them to be better managed." When Sylvan paid $ 50 million for a controlling stake in UVM two years ago, the school had revenues of about $ 80 million and an enrollment of 32,000. The success of the for-profits is nothing to be afraid of, says World Bank education expert Jamil Salmi: "I don't think they will replace traditional universities, but they can push some more traditional providers to be more innovative and more attentive to the needs of the labor market."
Some students at Sylvan schools in Latin America welcome the foreign invasion. At the Universidad de las Americas in Santiago, Daniela Villagran says friends tease her
According to the interviewee, all of the following can parents do to save money EXCEPT ______.
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