量子力学,,en,粒子与相互作用,,en,还原论,,en,古典物理学,,en,量子力学的历史渊源,,en,量子场论,,en,量子力学-解释,,en,狭义相对论,,en,光速,,en,狭义相对论的解释,,en,电子书版本的《粒子与相互作用》现已推出,,en,可作为与移动设备兼容的设计精美的可打印电子书提供,,en,立即获取,,en,质量管理,,de,是小事物的物理学,,en,他们的行为举止如何相互影响,,en,QM的这种框架明显缺席的原因,,en,为什么小事情做什么,这是质量管理一个问题,,en,如果您要在这个主题上取得进展,,en,最好的选择是遏制问为什么,,en,自然就是她,,en

Particles and Interactions

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量子力学,,en,粒子与相互作用,,en,还原论,,en,古典物理学,,en,量子力学的历史渊源,,en,量子场论,,en,量子力学-解释,,en,狭义相对论,,en,光速,,en,狭义相对论的解释,,en,电子书版本的《粒子与相互作用》现已推出,,en,可作为与移动设备兼容的设计精美的可打印电子书提供,,en,立即获取,,en,质量管理,,de,是小事物的物理学,,en,他们的行为举止如何相互影响,,en,QM的这种框架明显缺席的原因,,en,为什么小事情做什么,这是质量管理一个问题,,en,如果您要在这个主题上取得进展,,en,最好的选择是遏制问为什么,,en,自然就是她,,en (QM) is the physics of small things. How do they behave and how do they interact with each other? Conspicuously absent from this framework of QM is why. Why small things do what they do is a question QM leaves alone. And, if you are to make any headway into this subject, your best bet is to curb your urge to ask why. Nature is what she is. 我们的工作是了解她玩现实游戏的规则,,en,并尽我们最大的努力利用这些规则来在实验和技术上占优势,,en,我们的理由不是,,en,真,,en,话说回来,,en,我知道我们需要一些动力,,en,类似的解释,,en,至于为什么小东西,,en,粒子,,en,行为不同于我们直觉上的想象,,en,物质的小水滴,,en,去做,,en,我可以给您三个答案,它们的哲学难度越来越高,,en,观察问题,,en,观察或测量是与所观察到的相互作用,,en,互动可能会改变观察,,en,让我从现实世界中得出一个艰难的类比,,en,鲨鱼是好奇的生物,,en,如果你在水中th动,,en, and do our best to make use of those rules to our advantage in experiments and technologies. Ours is not to reason why. Really.

Having said that, I know that we need some motivation, some semblance of an explanation, as to why small things (particles) behave differently from what we intuitively imagine them (tiny little droplets of matter) to do. I can give you three answers with increasing levels of philosophical difficulty.

Problem of Observation

An observation or a measurement is an interaction with what is being observed. And an interaction can potentially change the observation. Let me draw a labored analogy from the real world: sharks are inquisitive creatures. If you are thrashing about in the water, 一位伟大的白人可能会感到好奇,并决定“观察”或对您进行测量,,en,为你不幸,,en,鲨鱼没有四肢可以与您结账,,en,所以他们咬了一口,,en,可以改变观察到的结果,,en,即你,,en,这是我们尝试定位电子时大致所做的事情,,en,我们用高能辐射轰炸它以观察,,en,但是到我们看到它的时候,,en,我们本来可以让它飞向上帝知道方向,,en,可以将质量管理视为解决此观察困难的框架,,en,尽管这种思路不太正确,,en,超越知觉的理论,,en,关于质量管理的一种稍微合适的思考方法仍然涉及人类的感知,,en,在上一篇文章中,我们看到了经典物理学,,en,这是,,en. Unfortunately for you, sharks don’t have any limbs to check you out with. So they take a bite, which has the effect of changing what is being observed, namely you. This is roughly what we are doing when we try to locate an electron. We bombard it with an energetic radiation to observe, but by the time we get to see it, we would have sent it flying in god knows what direction. QM can be thought of as a framework to handle this observational difficulty, although this line of thinking is not quite right.

Theory beyond Perception

A slightly more appropriate way of thinking about QM still involves human perception. We saw in the previous post that we have classical physics (which is, 总的来说,,en,我们常识的数学演绎,,en,处理人类规模的现象,,en,一旦我们突破了知觉装置的界限,,en,然而,,en,我们无权根据我们的常识期望事物遵循框架,,en,只是不适用于这些域,,en,粒子及其相互作用存在于我们常识之外的现实中,,en,如果你考虑一下,,en,一定是那样,,en,水分子的组成,,en,即氢和氧,,en,别像水一样,,en,原子的组成,,en,电子和质子,,en,不必表现任何类似的事情,,en,粒子不是物质的小液滴,,en,它们是奇怪的实体,其属性我们无法直观地把握,,en, a mathematical rendition of our common sense) to handle phenomena taking place at human scales. Once we breach the boundaries of our perceptual apparatus, however, we have no right to expect things to follow the framework based on our common sense, which just doesn’t apply in those domains. In other words, particles and their interactions exist in a reality that is beyond our common sense.

If you think about it, it has to be that way. The constituents of a water molecule, namely hydrogen and oxygen, don’t behave anything like water. Similarly, constituents of an atom, electrons and protons, do not have to behave anything like matter. Particles are not little droplets of matter. They are strange entities with properties that we cannot intuitively grasp. 我们很幸运,那些聪明的物理学家想出了量子力学,,en,哪些粒子和相互作用似乎确实服从,,en,观察量子力学的第三种方法,即哲学上的难题,还是基于感知和现实,,en,虽然我们没有这样描述,,en,经典物理学背后的哲学假设是显而易见的,,en,这可能就是为什么没人愿意描述它的原因,,en,我们假设我们的感官和测量仪器能够并且确实忠实地感知和报告现实,,en,有一个物理现实,,en,我们直接感觉到它的功能,,en,这些特征构成了我们构建物理学的基础,,en,如图,,en,现在,,en,数字,,en,我们的现实感,,en,以及它在物理学中的用法,,en, which particles and interactions do seem to obey.

Perception, Physics and Philosophy

The third and philosophically hard way of looking at Quantum Mechanics is again in terms of perception and reality. Although we didn’t describe it that way, the philosophical assumption behind classical physics is an obvious one, which is probably why nobody takes the trouble to describe it. We assume that our senses and our measuring apparatuses can and do perceive and report the reality faithfully. In other words, there is a physical reality out there, and we just sense its features directly. These features form the basis on which we build our physics, as shown in Figure 1 below.

now

Figure 1. Our sense of reality, and how it is used in physics

However, 我们没有特殊的理由去相信现实,,en,我们知道听觉创造的现实,,en,声音,,en,音调等,,en,与感觉到的无关,,en,气压波,,en,频率等,,en,气味与任何真实的事物都相去甚远,,en,引起它们的分子的物理性质,,en,我们还知道,蝙蝠回声定位空间中的运动学与我们的空间有很大不同,,en,蝙蝠空间,,en,与狭义相对论的空间几乎相同,声音的速度取代了光的速度,,en,不过那是另一回事了。,,en,空间,,en,气味等,,en,只是代表我们大脑接收信号的认知模型,,en,这些模型可以帮助我们导航和生存,,en,但是它们本身不是现实,,en. After all, we know that the reality created by our auditory sense (sound, tone etc.) has nothing to do with what is being sensed (air pressure waves, frequency etc.) Similarly, smells are a far cry from any real, physical properties of the molecules causing them. We also know that the kinematics in a bat’s echolocated space is very different from that of our space. (In fact, the bat space is pretty much identical to the space in Special Relativity with the speed of sound replacing that of light; but that is another story.)

Space, sound, smell etc. are merely cognitive models representing the signals that our brain receives. These models help us navigate and survive. But they are not reality itself. 因此,我们应该牢记的现实情况如下图所示,,en,产生我们的感知数据输入的不可知的绝对现实,,en,创造我们感知的现实,,en,当涉及到空间和物体时,,en,我们误认为这是真实的现实,,en,并尝试使用我们的科学机制对其进行描述,,en,现实,,en,关于现实及其在物理学中应如何使用的更准确的思考方式,,en,这是中间的街区,,en,古典物理学很好地描述了“感知现实”,,en,而正是量子力学中缺少的这一块,,en,我们没有认知模型,,en,我们的思想不能很好地应对它的缺席,,en,因此,我们尝试提出填补这一空白的解释,,en,最好的事情,,en 2. There is an unknowable absolute reality generating our sense data inputs, which create our perceived reality. When it comes to space and objects, we mistake it to be the true reality, and try to describe it using our scientific machinery.

reality
Figure 2. A more accurate way of thinking about reality and how it should be used in physics

It is the middle block, “Perceived Reality” that classical physics describes so well. And it is this block that lacking in Quantum Mechanics. We do not have a cognitive model, and our minds cannot deal with its absence too well. So we try to come up with interpretations that fill this void. The best thing to do, however, 就是相信作为质量管理工具的数学框架可以了解绝对现实之间的联系,,en,引起我们感知现实的原因,,en,以及我们可以进行实验和测试的科学,,en,我确实警告过您,我的第三种解释在哲学上很难,,en,现在,我们走到了绝对现实与感知现实之间的区别,,en,让我们更进一步,,en,可以将感知和认知的影响与我们的感知现实区分开来,,en,尽管假设了绝对现实的几何形状,,en,并为,,en,某些天体现象,,en,我的书,,en,基于这种思路,,en,在下一篇文章中,,en,我们将摆脱这种哲学的讨论,,en (the cause giving rise to our perceived reality) and the science that we can do experiments with and test. Well, I did warn you that this third interpretation of mine was philosophically hard.

Now that we came this far with the distinction between absolute reality and perceived reality, let’s take it a bit further. It is possible to disentangle the effects of perception and cognition from our perceived reality (albeit by assuming a geometry for the absolute reality) and work out interesting models for certain astrophysical phenomena. My book The Unreal Universe is based on this line of thinking.

In the next post, we will get out of this philosophical discussion, 并描述物理学家如何知道古典物理学是不完整的,并且他们需要一种新的理论来处理小事情,,en,现代物理学,,en,量子力学,,en.

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