薛定谔的猫英文版

Austrian physicist Erwin Schrodinger is one of the founders of quantum mechanics,but he’s most famous for something he never actually did:a thought experiment involving a cat.He imagined taking a cat and placing it in a sealed box with a device that had a 50% chance of killing the cat in the next hour.At the end of that hour,he asked,“What is the state of the cat?”Common sense suggests that the cat is either alive or dead,but Schrodinger pointed out that according to quantum physics,at the instant before the box is opened,the cat is equal parts alive and dead,at the same time.It’s only when the box is opened that we see a single definite state.Until then,the cat is a blur of probability,half one thing and half the other.This seems absurd,which was Schrodinger’s point. He found quantum physics so philosophically disturbing,that he abandoned the theory he had helped make and turned to writing about biology.As absurd as it may seem,though,Schrodinger’s cat is very real.In fact,it’s essential.If it weren’t possible for quantum objects to be in two states at once,the computer you’re using to watch this couldn’t exist.The quantum phenomenon of superposition is a consequence of the dual particle and wave nature of everything.In order for an object to have a wavelength,it must extend over some region of space,which means it occupies many positions at the same time.The wavelength of an object limited to a small region of space can’t be perfectly defined,though.So it exists in many different wavelengths at the same time.We don’t see these wave properties for everyday objects because the wavelength decreases as the momentum increases.And a cat is relatively big and heavy.If we took a single atom and blew it up to the size of the solar system,the wavelength of a cat running from a physicist would be as small as an atom within that Solar System.That’s far too small to detect,so we’ll never see wave behavior from a cat.A tiny particle,like an electron,though,can show dramatic evidence of its dual nature.If we shoot electrons one at a time at a set of two narrow slits cut in a barrier,each electron on the far side is detected at a single place at a specific instant,like a particle.But if you repeat this experiment many times,keeping track of all the individual defections,you’ll see them trace out a pattern that’s characteristic of wave behavior:a set of stripes-regions with many elections separated by regions where there are none at all.Block one of the slits and the stripes go away.This shows that the pattern is a result of each electron going through both slits at the same time.A single electron isn’t choosing to go left or right but left and right simultaneously.This superposition of states also leads to modern technology.An electron near the nucleus of an atom exists in a spread out,wave-like orbit.Bring two atoms close together,and electrons don’t need to choose just one atom but are shared between them.This is how some chemical bonds form.An electron in a molecule isn’t on just atom A or atom B,but A+B.As you add more atoms,the electrons spread out more,shared between vast numbers of atoms at the same time.The electrons in a solid aren’t bound to a particular atom but shared among all of them,extending over a large range of space.This gigantic superposition of states determines the ways electrons move through the material,whether it’s a conductor or an insulator or a semiconductor.Understanding how electrons are shared among atoms allows us to precisely control the properties of semiconductor materials,like bining different semiconductors in the right way allows us to make
transistors on a tiny scale,millions on a single computer you’re using to watch this video.An old joke says that the Internet exists to allow the sharing of cat videos.At a very deep level,though,the Internet owes its existence to an Austrian physicist and his imaginary cat.
奥地利物理学家埃尔文·薛定谔是量子力学的奠基人之一，但是他最为大众所知的却是他从未做过的一项试验，一个关于猫的思想试验。

他假想将一只猫置于一个密闭盒子内，里面安放了一个一小时内有50%几率杀死猫的装置。

一个小时后，他提出一个问题：现在猫是活的还是死的。

常识告诉我们猫不是活的就是死的，但是薛定谔指出，根据量子物理，在打开盒子的前一瞬间，猫既是活的也是死的，即猫同时处于生与死的混合状态。

只有打开盒子我们才能知道猫是生还是死，除此之外，猫一直处于一种混沌可能性的状态，既生又死。

薛定谔的观点听起来很荒谬，他发觉量子物理如此难以理解，以至于他本人都放弃验证此理论，并转而研究生物。

虽然薛定谔的猫看上去很荒谬，但是他却是很真实的。

实际上，也是很重要的。

如果量子物理不能同时处于双重状态，我们现在用来观看此视频的电脑就不会存在。

量子的叠加现象，是自然物质波粒二象性作用的结果。

一个物体要想有波长，就必须扩展空间范围，这就意味着它必须同时占据许多位置，限制在很小空间的不可能太明晰物体的波长，所以它同时存在于波长内的许多不同地点。

我们在日常生活的物品中看不到这些波，因为波长在变短的同时却有增长的趋势，而因为猫相对而言比较大和重。

如果我们取一个原子并放大到太阳系大小，那么猫奔向物理学家产生的波长就相当于太阳系里的一个小原子，它小到很难探测，所以我们从未看到猫的波动。

但是很小的物质，比如说一个电子，却是能表明波粒二象性存在的证据。

如果我们一次把一个电子射向一个有两个狭窄裂缝的装置，远处的电子会像物质一样马上被测出在哪个位置。

我们大量重复此实验，持续追踪所有电子的轨迹，你会发现它们的轨迹表现出了波的特征，条纹区间内集聚了大量电子夹杂在没有电子的区间之中，遮挡住一个细微裂缝，条纹区间就不复存在，这表明电子的集聚形式是电子，同时有两个裂缝可穿过的作用结果。

一个电子无法选择通过哪个裂缝，但是通过裂缝的电子却是同时发生的，这种状态叠加也可由现代科学解释：绕原子核旋转的电子的轨道是分散的似波轨道，使两个原子靠近，电子不需要选择原子轨道，只需要共享轨道，这就是化学键的形式。

分子中的电子不是在原子A或B中，是在A和B中。

如果你添加更多的原子，电子会更加扩散，同时被大量原子共享，电子并不是牢固地绕某个原子旋转，却在空间内绕着分子旋转。

这种庞大的状态叠加，表明了电子是如何运动的，不论是在导体，绝缘体还是半导体之间。

了解电子被原子共享的方式，使我们有可能精确地控制半导材料的性能，比如说硅，将不同的半导体以正确的方式组合，令我们可以将晶体管制造成很小的规模，集成大规模作成电路放在电脑芯片里。

这些芯片和扩散的电子，掌握你们正在看此视频的电脑。

有这么一个老笑话，互联网的存在使我们可以在网上撸猫，但是溯本求源，互联网的出现，却要归功于一位奥地利物理学家和那只虚构的猫。