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出了一種后來被稱之為量子力學(xué)的新理論。該理論的核心是"海森伯測不準原理"。想要知道電子的軌跡，就必定影響我們測得電子在某一瞬間的確切位置。這與測量儀器精密與否無關(guān)，而是宇宙中不變的特性~~~ ?《萬物簡史》推出部落節(jié)目版，戳這里訂閱: 文中需聽寫單詞或詞組用[-No-]表示，句子用[---No---]表示。請邊聽寫邊理解文意，這樣可以提高聽力準確度，并為訓(xùn)練聽譯打下基礎(chǔ)哦~~~ Hint: immutable Finally, in 1926, Heisenberg came up with [-1-], producing a new discipline that came to be known as quantum mechanics. At the heart of it was Heisenberg's Uncertainty Principle, which states that the electron is a particle but a particle that can be described in terms of waves. [---2---] Any attempt to measure one will [-3-] disturb the other. [---4---] There is a little uncertainty about the use of the word uncertainty [-5-] Heisenberg's principle. Michael Frayn, in an afterword to his play Copenhagen, notes that several words in German-Unsicherheit, Unscharfe, Unbestimmtheit-have been used by various translators, [-6-] . Frayn suggests that indeterminacy would be a better word for the principle and indeterminability would be better still. a celebrated compromise The uncertainty around which the theory is built is that we can know the path an electron takes as it moves through a space or we can know where it is at a given instant, but we cannot know both. unavoidably This isn't a matter of simply needing more precise instruments; it is an immutable property of the universe. in regard to but that none quite equates to the English uncertainty 1926年，海森伯終于想出個極好的妥協(xié)辦法，提出了一種后來被稱之為量子力學(xué)的新理論。該理論的核心是"海森伯測不準原理"。它認為，電子是一種粒子，不過是一種可以用波來描述的粒子。作為建立該理論基礎(chǔ)的"測不準原理"認為，我們可以知道電子穿越空間所經(jīng)過的路徑，我們也可以知道電子在某個特定時刻的位置，但我們無法兩者都知道。任何想要測定其中之一的努力，勢必會干擾其中之二。這不是個需要更精密的儀器的簡單問題；這是宇宙的一種不可改變的特性。 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>

今天的實驗中，那個偉大的實驗出現(xiàn)了——α粒子散射實驗。被電離的氦原子射向金箔，結(jié)果被結(jié)結(jié)實實地彈回來，就好像一顆38厘米的炮彈被一張紙談回來一樣。如此奇怪的現(xiàn)象讓盧瑟福不得不對原子結(jié)構(gòu)傳統(tǒng)觀念提出挑戰(zhàn)——原子內(nèi)部主要是空無一物的空間，只有當中是密度很大的核~~~ ?《萬物簡史》推出部落節(jié)目版，戳這里訂閱: 文中需聽寫單詞或詞組用[-No-]表示，句子用[---No---]表示。請邊聽寫邊理解文意，這樣可以提高聽力準確度，并為訓(xùn)練聽譯打下基礎(chǔ)哦~~~ In 1910, Rutherford (assisted by his student Hans Geiger, who would later invent the radiation detector that [-1-] his name) fired ionized helium atoms, or alpha particles, at a sheet of gold foil. [---2---] To Rutherford's astonishment, some of the particles bounced back. It was as if, he said, he had fired a 15-inch shell at a sheet of paper and it rebounded into his lap. [---3---] After [-4-] he realized there could be only one possible explanation: [---5---] An atom, Rutherford realized, was mostly empty space, with a very dense nucleus at the center. This was a most [-6-] discovery, but it presented one [-7-] problem. [---8---] bears Geiger would also later become a loyal Nazi, unhesitatingly betraying Jewish colleagues, including many who had helped him. This was just not supposed to happen. considerable reflection the particles that bounced back were striking something small and dense at the heart of the atom, while the other particles sailed through unimpeded. gratifying immediate By all the laws of conventional physics, atoms shouldn't therefore exist. 1910年，盧瑟福（在他的學(xué)生漢斯?蓋格的協(xié)助之下。蓋格后來將發(fā)明冠有他名字的輻射探測儀）朝一塊金箔發(fā)射電離的氦原子，或稱α粒子。蓋格后來還成為一個忠實的納粹分子，出賣了他的猶太同事，其中包括很多曾經(jīng)幫助過他的人。令盧瑟福吃驚的是，有的粒子竟會反彈回來。他說，他就像朝一張紙發(fā)射了一發(fā)38厘米的炮彈，結(jié)果炮彈反彈到了他的膝部。這是不該發(fā)生的事。經(jīng)過冥思苦想以后，他覺得只有一種解釋：那些反彈回來的粒子擊中了原子當中又小又密的東西，而別的粒子則暢通無阻地穿了過去。盧瑟福意識到，原子內(nèi)部主要是空無一物的空間，只有當中是密度很大的核。這是個很令人滿意的發(fā)現(xiàn)。但馬上產(chǎn)生了一個問題，根據(jù)傳統(tǒng)物理學(xué)的全部定律，原子因此就不應(yīng)該存在。 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>

說是"無法解脫地交織在一起"--不可思議地形成一份"時空"。引力--時空彎曲的一種產(chǎn)物。（大家堅持下，物理課快結(jié)束了）~~~ ?《萬物簡史》推出部落節(jié)目版，戳這里訂閱: 文中需聽寫單詞或詞組用[-No-]表示，句子用[---No---]表示。請邊聽寫邊理解文意，這樣可以提高聽力準確度，并為訓(xùn)練聽譯打下基礎(chǔ)哦~~~ Hints: sag ineluctably The most challenging and nonintuitive of all the concepts in the general theory of relativity is the idea that time is part of space. Our instinct is to regard time as [-1-], absolute, immutable—nothing can disturb its steady tick. In fact, according to Einstein, time is [-2-] and [-3-]. It even has shape. It is bound up—"inextricably interconnected," in Stephen Hawking's expression—[---4---] Spacetime is usually explained by asking you to imagine something flat but pliant—a mattress, say, or a sheet of stretched rubber—on which is resting a heavy round object, such as an iron ball. [---5---] This is roughly analogous to the effect that a massive object such as the Sun (the iron ball) has on spacetime (the material): it [-6-] and curves and warps it. [---7---] This is gravity—a product of the bending of spacetime. eternal variable ever changing with the three dimensions of space in a curious dimension known as spacetime. The weight of the iron ball causes the material on which it is sitting to stretch and sag slightly. stretches Now if you roll a smaller ball across the sheet, it tries to go in a straight line as required by Newton's laws of motion, but as it nears the massive object and the slope of the sagging fabric, it rolls downward, ineluctably drawn to the more massive object. 在"廣義相對論"的眾多概念中，最具挑戰(zhàn)性的，最直覺不到的，在于時間是空間的組成部分這個概念。我們本能地把時間看做是永恒的，絕對的，不可改變的，相信什么也干擾不了它的堅定步伐。事實上，愛因斯坦認為，時間是可以更改的，不斷變化的。時間甚至還有形狀。一份時間與三份空間結(jié)合在一起--用斯蒂芬?霍金的話來說是"無法解脫地交織在一起"--不可思議地形成一份"時空"。 　　通常，時空是這樣解釋的：請你想像一樣平坦而又柔韌的東西--比如一塊地毯或一塊伸直的橡皮墊子--上面放個又重又圓的物體，比如鐵球。鐵球的重量使得下面的底墊稍稍伸展和下陷。這大致類似于太陽這樣的龐然大物（鐵球）對于時空（底墊）的作用：鐵球使底墊伸展、彎曲、翹起。現(xiàn)在，要是你讓一個較小的球從底墊上滾過去，它試圖做直線運動，就像牛頓運動定律要求的那樣。然而，當它接近大球以及底墊下陷部分的時候，它就滾向低處，不可避免地被大球吸了過去。這就是引力--時空彎曲的一種產(chǎn)物。 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>

裹在原子核里。質(zhì)子和中子裝在原子核里，而電子在外面繞著旋轉(zhuǎn)。質(zhì)子的數(shù)量決定一個原子的化學(xué)特性~~~ ?《萬物簡史》推出部落節(jié)目版，戳這里訂閱: 文中需聽寫單詞或詞組用[-No-]表示，句子用[---No---]表示。請邊聽寫邊理解文意，這樣可以提高聽力準確度，并為訓(xùn)練聽譯打下基礎(chǔ)哦~~~ Let us pause for a moment and consider the structure of the atom as we know it now. Every atom [-1-] three kinds of elementary particles: protons, which have a positive electrical charge; electrons, which have a negative electrical charge; and neutrons, which have no charge. Protons and neutrons [-2-] the nucleus, while electrons spin around outside. [---3---] An atom with one proton is an atom of hydrogen, one with two protons is helium, with three protons is lithium, [-4-] . Each time you add a proton you get a new element. ([---5---], you will sometimes see it written that it is the number of electrons that defines an element; it comes to the same thing. [---6---]) Neutrons don't influence an atom's identity, but they do add to its mass. [---7---] Add a neutron or two and you get an isotope. The terms you hear [-8-] dating techniques in archeology refer to isotopes--carbon-14, for instance, which is an atom of carbon with six protons and eight neutrons ([-9-]). is made from are packed into The number of protons is what gives an atom its chemical identity. and so on up the scale Because the number of protons in an atom is always balanced by an equal number of electrons The way it was explained to me is that protons give an atom its identity, electrons its personality. The number of neutrons is generally about the same as the number of protons, but they can vary up and down slightly. in reference to the 14 being the sum of the two 讓我們稍停片刻，先來考慮一下現(xiàn)在我們所

想用肉眼看到草履蟲在一滴水里游，你非得把這滴水放大到12米寬。然而，要是你想看到同一滴水里的原子，你非得把這滴水放大到24公里寬。 　　換句話說，原子完全存在于另一種微小的尺度上。若要知道原子的大小，你就得拿起這類微米大小的東西，把它切成10000個更小的東西。那才是原子的大?。?毫米的千萬分之一．這么小的東西遠遠超出了我們的想像范圍。但是，只要記住，一個原子對于上述那條1毫米的線，相當于一張紙的厚度對于紐約帝國大廈的高度，它的大小你就有了個大致的概念。 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>

也許說明了道爾頓的早熟，也說明了那所學(xué)校的狀況，也許什么也說明不了。我們從他的日記里知道，大約這時候他正在閱讀牛頓的《原理》--還是拉丁文原文的--和別的具有類似挑戰(zhàn)性的著作。到了15歲，他一方面繼續(xù)當校長，一方面在附近的肯達爾鎮(zhèn)找了個工作；10年以后，他遷往曼徹斯特，在他生命的最后50年里幾乎沒有挪動過。在曼徹斯特，他成了一股智力旋風(fēng)，出書呀，寫論文呀，內(nèi)容涉及從氣象學(xué)到語法。他患有色盲，在很長時間里色盲被稱做道爾頓癥，因為他從事這方面的研究。但是，是1808年出版的一本名叫《化學(xué)哲學(xué)的新體系》的厚書，終于使他出了名。 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>

多比銀河系要大，要遠得多。 僅僅這一項發(fā)現(xiàn)就足以使哈勃名揚天下，但是，他接著把注意力轉(zhuǎn)向另一個問題，想要計算宇宙到底大了多少，于是有了一個更加令人矚目的發(fā)現(xiàn)。哈勃開始測量遠方星系的光譜--斯萊弗已經(jīng)在亞利桑那州開始做的那項工作。他利用威爾遜山天文臺那臺新的254厘米天文望遠鏡，加上一些聰明的推斷，到20世紀30年代初已經(jīng)得出結(jié)論：天空中的所有星系（除我們自己的星系以外）都在離我們遠去。而且，它們的速率和距離完全成正比：星系距離我們越遠，退行速率越快。 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>

也是第一次有人想出了一個計算浩瀚宇宙的實用方法。 （為了合理評價這些深邃的見解，也許值得注意的是，當萊維特和坎農(nóng)在根據(jù)照片上遠方星星的模糊影子推定宇宙的基本特性的時候，哈佛大學(xué)的天文學(xué)家威廉?H.皮克林--他當然能從一流的天文望遠鏡里想觀察多少次就觀察多少次--卻在建立自己的理論，認為月球上的黑影是由大群大群的、隨著季節(jié)遷徙的昆蟲形成的。） 這篇材料你能聽出多少？點擊這里做聽寫，提高外語水平>>