The speed of light being a constant sounds like a simple statement. But there is more to it, quite a bit more. Let’s look at what this constancy really means. 乍一看, it says that if you are standing somewhere, and there is a ray of light going from your right to left, it has a speed Ç. And another ray of light going from left to right also has a speed Ç. So far, so good. Now let’s say you are in a rocket ship, 如下面的图中, moving from right to left.
当我们听到有关爱因斯坦的狭义相对论 (或者相对论狭义相对论, 使用真实姓名), 我们认为著名的 方程, 而奇怪的事情就像孪生佯谬. 虽然这些东西都是真实和重要, SR试图解决的问题是一个完全不同的一个. 这是捍卫物理学基本原理的尝试.
Whenever we talk about Quantum Mechanics, one of the first questions would be, “What about the cat?” This question, 真, is about the interpretations of Quantum Mechanics. The standard interpretation, 所谓哥本哈根解释, leads to the famous Schrodinger’s cat.
In this post on Quantum Mechanics (QM), we will go a bit beyond it and touch upon Quantum Field Theory – the way it is used in particle physics. In the last couple of posts, I outlined a philosophical introduction to QM, as well as its historical origin – how it came about as an ad-hoc explanation of the blackbody radiation, and a brilliant description of the photoelectric effect.
In this section, we will try to look at the historical origin of Quantum Mechanics, which is usually presented succinctly using scary looking mathematical formulas. The role of mathematics in physics, as Richard Feynman explains (in his lectures on QED given in Auckland, New Zealand in 1979, available on YouTube, but as poor quality recordings) is purely utilitarian.
量子力学 (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. 和, 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. Our job is to understand the rules by which she plays the game of reality, and do our best to make use of those rules to our advantage in experiments and technologies. Ours is not to reason why. Really.
The main difficulty in describing particle physics to general public is the fact that it is built on modern physics. Even if you are physics aficionado and did extremely well in your high school physics, what you have learned and loved is classical physics. The difference between classical physics and modern physics is not just more physics, but a completely new way of looking at the reality around us.
在我们所有的科学努力, 我们使用类似高层次的技术，了解和研究的东西. 最常用的技术是还原. 它是基于相信该行为, 庞大而复杂的对象的属性和结构可以在其简单的成分来理解. 换句话说, 我们试图了解整个 (宇宙, 例如) 在较小的方面, 减少成分 (如颗粒).
最近, 我介绍了粒子和相互作用，以我女儿的同学谁是打算前往德国电子同步加速器研究所的演讲, 德国，想拥有这是什么一回事的想法. 由于我的这种先说说, 我有点紧张，因为我不知道什么级别, 和背景, 我应该挂在谈话. 我不想弄得太基本, 我本以为这是浪费时间. 我也不想让它太技术, 这也将使得它以不同的方式无用.
Animals have different sensory capabilities compared to us humans. Cats, 例如, can hear up to 60kHz, while the highest note we have ever heard was about 20kHz. 似乎, we could hear that high a note only in our childhood. 所以, if we are trying to pull a fast one on a cat with the best hifi multi-channel, Dolby-whatever recording of a mouse, we will fail pathetically. It won’t be fooled because it lives in a different sensory world, while sharing the same physical world as ours. There is a humongous difference between the sensory and physical worlds.