首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Cosmology is sometimes pooh-poohed as more philosophy than science. It asks deep questions about nature but provides unsatisfyin
Cosmology is sometimes pooh-poohed as more philosophy than science. It asks deep questions about nature but provides unsatisfyin
admin
2009-08-13
76
问题
Cosmology is sometimes pooh-poohed as more philosophy than science. It asks deep questions about nature but provides unsatisfyingly vague answers. The cosmos may be 12 billion years old, but it could be as much as 15 billion. The stars began to shine 100 million years after the Big Bang, or maybe it’s a billion. "Our ideas," acknowledges Max Tegmark of the University of Pennsylvania, "have been kind of wobbly."
But much of the wobble has been fixed, thanks to a satellite known as the Wilkinson Microwave Anisotropy Probe, or WMAP. 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 universe: 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."
选项
A、tend to think more about philosophy than science.
B、have wrongly calculated the age of the cosmos.
C、don’t know for sure about our cosmos.
D、expect to solve all the problems about nature.
答案
C
解析
本题是推断题。由题干定位至首段。首句指出宇宙学受到的质疑:相比于科学而言,更像是哲学。第二句解释原因:It asks deep questions about nature but provides unsatisfyingly vague answers.末句“Our ideas... have been kind of wobbly”再次说明宇宙学家们对于宇宙的很多问题都无法给出明确的答案,[C]符合文意,故为答案。首句是宇宙学受到的质疑,不是宇宙学家们想做的事情,[A]不符合文意。
转载请注明原文地址:https://kaotiyun.com/show/FovO777K
0
专业英语八级
相关试题推荐
Honda’sworldwideoutputincreasedto______in2005.
Accordingtothespeaker,theareaofgreatestexpenditureofinvestmentfundsoccurredin______.
Whenisadriverlikelytohaveasleep-relatedaccidentaccordingtoresearchers?
TheTsunamithatoccurredinNovember2004killedover140,000people,leavingseveralmillionhomelessinAcehProvinceandSri
Oursocietyisnowbeingreshapedbyrapidadvancesininformationtechnologies—computers,telecommunicationsnetworks,andot
Itcanbeinferredfromthepassagethat______.
TheincreasingnumberoftheunaccompaniedchildrenacrosstheU.S.borderpresstheUnitedStatestodetainmoreandmorechil
A、TalkingtoomuchinbusinessnegotiationsleavesabadimpressionoAmericans.B、SilenceoftenmakesAmericansfeeluncomforta
CertainphrasesonecommonlyhearsamongAmericanswhich(1)toindividualisminclude:"Doyourownthing.""Ididitmyway."
Ifyou’veeverbeenonajury,youmighthavenoticedthatafunnythinghappenstheminuteyougetbehindcloseddoors.Everybo
随机试题
发生在口腔颌面部的红斑狼疮亚型是
下列哪项非精亏神衰的失神表现
A.六味地黄丸B.一般应从最小剂量开始C.不宜佐健脾和胃之品D.不宜用苦寒之品E.柏子养心丸老年人中药的使用应做到()
某建筑公司在对一办公大楼实行定向爆破拆除时,由于设计不合理,爆破时造成附近建筑堆置物倒塌伤人事故。按照《企业职工伤亡事故分类标准》(GB6441—1986),该起事故的类别是()。
背景资料:某客运专线2标段工程由某集团公司担负施工,标段内有路基、桥涵、隧道、CRTSⅠ型板式无砟轨道工程(不合铺轨),主要工程分布如下图所示。标段内的梁体为双线整孔箱梁,采取场制和现场架梁,计划每天架梁2孔,1号特大桥梁部
2×20年1月1日,A公司以每股5元的价格购入B上市公司(以下简称“B公司”)股票10万股,并由此持有B公司2%股权。A公司将对B公司的该项投资作为以公允价值计量且其变动计入当期损益的金融资产核算。2×21年1月1日,A公司以现金1750万元作为对价,向B
神经元是由()组成的。
某商场为促销,在五一期间开展返券活动。某女士在该商场依次购买了标价为748元、978元、350元的商品(这三样商品都能参与返券),共计消费1476元,且手头无剩余返券。则该商场的返券活动为()。
从行文方向看,意见属于(),适用范围非常广泛。
TheethicaljudgmentsoftheSupremeCourtjusticeshavebecomeanimportantissuerecently.Thecourtcannot【C1】______itsleg
最新回复
(
0
)