万物简史 第241期:马斯特-马克的夸克(13)

Hubble realized that this could be expressed with a simple equation, Ho = v/d (where Ho is the constant, v is the recessional velocity of a flying galaxy, andd its distance away from us). Ho has been known ever since as the Hubble constant and the wh

万物简史 第242期:马斯特-马克的夸克(14)

This would mean that the universe was only half the size and age that Sandage believedten billion years. Matters took a further lurch into uncertainty when in 1994 a team from the Carnegie Observatories in California, using measures from the Hubble s

万物简史 第243期:马斯特-马克的夸克(15)

The difficulty in making final determinations is that there are often acres of room for interpretation. Imagine standing in a field at night and trying to decide how far away two distant electric lights are. Using fairly straightforward tools of astr

万物简史 第235期:马斯特-马克的夸克(7)

The charged pion and antipion decay respectively into a muon plus antineutrino and an antimuon plus neutrino with an average lifetime of 2.603 x 10-8 seconds, the neutral pion decays into two photons with an average lifetime of about 0.8 x 10-16 seco

万物简史 第236期:马斯特-马克的夸克(8)

Although quarks are much too small to have color or taste or any other physical characteristics we would recognize, they became clumped into six categoriesup, down, strange, charm, top, and bottomwhich physicists oddly refer to as their flavors, and

万物简史 第234期:马斯特-马克的夸克(6)

Particle physics, in short, is a hugely expensive enterprisebut it is a productive one. Today the particle count is well over 150, with a further 100 or so suspected, but unfortunately, in the words of Richard Feynman, it is very difficult to underst

万物简史 第233期:马斯特-马克的夸克(5)

The intention of the collider was to let scientists probe the ultimate nature of matter, as it is always put, by re-creating as nearly as possible the conditions in the universe during its first ten thousand billionths of a second. The plan was to fl

万物简史 第232期:马斯特-马克的夸克(4)

CERN, the European Organization for Nuclear Research, is like a little city. Straddling the border of France and Switzerland, it employs three thousand people and occupies a site that is measured in square miles. CERN boasts a string of magnets that

万物简史 第231期:马斯特-马克的夸克(3)

Particles can come into being and be gone again in as little as 0.000000000000000000000001 second (10-24). Even the most sluggish of unstable particles hang around for no more than 0.0000001 second (10-7). 粒子可以在短达0.000 000 000 000 000 0

万物简史 第230期:马斯特-马克的夸克(2)

As physicists built bigger and more ambitious machines, 随着物理学家建造越来越大、越来越雄心勃勃的机器， they began to find or postulate particles or particle families seemingly without number: 他们开始或推断出似乎永无

万物简史 第229期:马斯特-马克的夸克(1)

11 Muster Mark's Quarks 第十一章 马斯特马克的夸克 IN 1911, A British scientist named C. T. R. Wilson was studying cloud formations by tramping regularly to the summit of Ben Nevis, 1911年，一位名叫C.T.R.威尔逊的英国科学家经常

万物简史 第406期:浩瀚的海洋(25)

Biologists, according to the New York Times, 据《纽约时报》说：生物学家们估计， estimate that 90 percent of lobsters are caught within a year after they reach the legal minimum size at about age six. 大龙虾大约在6岁达到法定的

万物简史 第408期:生命的起源(2)

Proteins are what you get when you string amino acids together, and we need a lot of them. 你把氨基酸串在一起，就得到了蛋白质。我们需要大量的蛋白质。 No one really knows, but there may be as many as a million types of pro

万物简史 第407期:生命的起源(1)

19 The Rise Of Life 第十九章 生命的起源 In 1953, Stanley Miller, a graduate student at the University of Chicago, took two flasksone containing a little water to represent a primeval ocean, 1953年，芝加哥大学的研究生斯坦利米勒拿

万物简史 第417期:生命的起源(11)

Fred Hoyle and his colleague Chandra Wickramasinghe further eroded enthusiasm for panspermia 我们已经在第三章里提到，弗雷德霍伊尔和他的同事钱德拉威克拉马辛格认为， by suggesting that outer space brought us not only

万物简史 第409期:生命的起源(3)

There are actually twenty-two naturally occurring amino acids known on Earth, 实际上，地救上有22种天然存在的氨基酸， and more may await discovery, but only twenty of them are necessary to produce us and most other living things. 更多

万物简史 第411期:生命的起源(5)

Without the cell, they are nothing more than interesting chemicals. 没有细胞，它们只是有意思的化学物质。 But without the chemicals, the cell has no purpose. 但要是没有这些化学物质，细胞就毫无用处。 As the physici

万物简史 第412期:生命的起源(6)

Well, that's essentially what Hoyle and others (including many ardent creationists) argue when they suggest that proteins spontaneously formed all at once. 哎呀，那基本上就是霍伊尔和其他人（包括许多热心的特创论者）提出的

万物简史 第413期:生命的起源(7)

De Duve thought it likely that such conditions would be encountered perhaps a million times in every galaxy. 德迪夫认为，很有可能，这样的条件在每个星系里大约会遇到100万次。 Certainly there is nothing terribly exotic in t

万物简史 第414期:生命的起源(8)

As one leading biology text puts it, with perhaps just a tiny hint of discomfort, 正如一篇重要的生物学文章所说，说得也许有点儿令人不大舒服： Researchers agree that such reactions would not have been energetically favorabl