汉语是联合国官方正式使用的6 种同等有效语言之一。请不要歧视汉语！ Chinese is one of the six equally effective official languages of the United Nations. Not to discriminate against Chinese, please! 宏观点电荷发出的磁场、电磁波 判定实验原理 我们地球表面，电磁屏蔽的大尺度内部空间，电场、磁场、电磁辐射都趋于0。 （1）加入微弱的磁场。小磁针有固定的指向。慢慢移入一个宏观点电荷，小磁针静止后是否偏转角度变化。再慢慢移入一个宏观点电荷，再次检查小磁针静止后是否偏转。 宏观点电荷反电性，再次实验。总共4种搭配。 （2）两个一样的宏观点电荷，放置一定的空间距离。它们是否会自动振动或移动（扣除库仑定律的作用）。 宏观点电荷反电性，再次实验。总共4种搭配。 感谢您的指教！ 感谢您指正以上任何错误！ 感谢您提供更多的相关信息 ！
汉语是联合国官方正式使用的6 种同等有效语言之一。请不要歧视汉语！ Chinese is one of the six equally effective official languages of the United Nations. Not to discriminate against Chinese, please! TA能发现这个电磁波吗？ 在静止的惯性系，一个宏观电荷 Q （下图的 矩形 ） 做简 谐振动，如下图： https://en.wikipedia.org/wiki/Vibration 静止惯性系的观察者 A ，能够发现这个简谐振动的点电荷 Q 发出的电磁波。 问题： 假定另一个观察者 B 和该点电荷 Q （上图的 矩形 ）绑定在一起， 由于观察者 B 和该点电荷 Q 保持了相对静止，根据库仑定律，观察者 B 能发现点电荷 Q 的静电场。 观察者 B 能发现点电荷 Q 激发的电磁波吗？ 这可不是开玩笑。 相关链接： 科学出版社 ，2015-08-10， 科学上过分漂亮的结论很有可能是以无中生有的方式编造出来的 精选 http://blog.sciencenet.cn/blog-528739-911890.html Vibration, From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Vibration 2018-8-28 ， 关于电磁场“场”概念的局限性、电荷能量的偶感 http://blog.sciencenet.cn/blog-107667-1131501.html 2016-10-13， 电磁学（物理学）的基础：磁场的起因 http://blog.sciencenet.cn/blog-107667-1008502.html 2015-09-06，rainsnow 老师：我的担忧并没有消失！！ http://blog.sciencenet.cn/blog-107667-918874.html 中国科学院科学智慧火花，2012-04-12，SI基本单位中安培定义的两种可能缺陷 http://idea.cas.cn/viewdoc.action?docid=4681 Williams E R, Faller J E, Hill H A. New experimental test of Coulomb's law: a laboratory upper limit on the photon rest mass . Physics Review Letters, 1971, 26(12): 721-724. http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.26.721 上面的素材卡通下载自互联网，感谢原作者！ 感谢您的指教！ 感谢您指正以上任何错误！ 感谢您提供更多的相关资料！
惠林之谏： 宇宙源于微观服从微观 张永和 宇宙存在的基本法则：运动，分解，连续，和谐，循环。 由运动而分解，由分解而连续，由连续而和谐，由和谐而循环。 物质有动能而运动，有粒子性而分解，有波动性而连续，有势能而和谐，有轨道而循环。 当分解与连续不和谐时，宇宙形成了 宏观世界，法则符合经典力学： a = F/m 。 当分解与连续和谐时，宇宙形成了微观世界， 法则符合波动力学： -h 2 2 / 8 2 m - Z e 2 /4 ? 0 r = E 核电荷力 Ze 2 受定域 r 制约所形成的势能 Z e 2 /r 就是 离子共价二象性 。 宇宙宏观源于微观，宏观必然性隶属于微观或然性。
Nature , 2010. DOI: 10.1038/nature08967 Nature , 2010. DOI: 10.1038/nature08998 如果有人告诉你，让你的头发处于量子状态，你会怎么想呢？ 这不是科幻，最新一期Nature杂志发表Andrew Cleland 研究组的文章，他们成功地将人眼可以看到的物体（约50微米）置于量子状态，让它处于动和不动的复合状态。他们的实验表明量子力学的原理不仅适用于原子而且可用于日常所见物体。 宏观物体的量子效应可以追溯到薛定谔的薛定谔猫的理想实验。没有明确的物理原理表明量子力学原理不适用于由微观粒子组成的宏观体。也就是说薛定谔猫也是可能现实存在的。 Scientists supersize quantum mechanics http://www.nature.com/news/2010/100317/full/news.2010.130.html#B1 Largest ever object put into quantum state. Geoff Brumfiel A team of scientists has succeeded in putting an object large enough to be visible to the naked eye into a mixed quantum state of moving and not moving. Andrew Cleland at the University of California, Santa Barbara, and his team cooled a tiny metal paddle until it reached its quantum mechanical 'ground state' the lowest-energy state permitted by quantum mechanics. They then used the weird rules of quantum mechanics to simultaneously set the paddle moving while leaving it standing still. The experiment shows that the principles of quantum mechanics can apply to everyday objects as well as as atomic-scale particles. The work is simultaneously being published online today in Nature and presented today at the American Physical Society's meeting in Portland, Oregon 1 . According to quantum theory, particles act as waves rather than point masses on very small scales. This has dozens of bizarre consequences: it is impossible to know a particle's exact position and velocity through space, yet it is possible for the same particle to be doing two contradictory things simultaneously. Through a phenomenon known as 'superposition' a particle can be moving and stationary at the same time at least until an outside force acts on it. Then it instantly chooses one of the two contradictory positions. But although the rules of quantum mechanics seem to apply at small scales, nobody has seen evidence of them on a large scale, where outside influences can more easily destroy fragile quantum states. No one has shown to date that if you take a big object, with trillions of atoms in it, that quantum mechanics applies to its motion, Cleland says. There is no obvious reason why the rules of quantum mechanics shouldn't apply to large objects. Erwin Schrdinger, one of the fathers of quantum mechanics, was so disturbed by the possibility of quantum weirdness on the large scale that he proposed his famous 'Schrdinger's cat' thought experiment. A cat is placed in a box with a vial of cyanide and a radioactive source. If the source decays, it triggers a device that will break the vial, killing the cat. During the time the box is shut, Schrdinger argued, the cat is in a superposition of alive and dead an absurdity as far as he was concerned. Wonderful weirdness Cleland and his team took a more direct measure of quantum weirdness at the large scale. They began with a a tiny mechanical paddle, or 'quantum drum', around 30 micrometres long that vibrates when set in motion at a particular range of frequencies. Next they connected the paddle to a superconducting electrical circuit that obeyed the laws of quantum mechanics. They then cooled the system down to temperatures below one-tenth of a kelvin. At this temperature, the paddle slipped into its quantum mechanical ground state. Using the quantum circuit, Cleland and his team verified that the paddle had no vibrational energy whatsoever. They then used the circuit to give the paddle a push and saw it wiggle at a very specific energy. Next, the researchers put the quantum circuit into a superposition of 'push' and 'don't push', and connected it to the paddle. Through a series of careful measurements, they were able to show that the paddle was both vibrating and not vibrating simultaneously. It's wonderful, says Hailin Wang, a physicist at the University of Oregon in Eugene who has been working on a rival technique for putting an oscillator into the ground state. The work shows that the laws of quantum mechanics hold up as expected on a large scale. It's good for physics for sure, Wang says. So if trillions of atoms can be put into a quantum state, why don't we see double-decker buses simultaneously stopping and going? Cleland says he believes size does matter: the larger an object, the easier it is for outside forces to disrupt its quantum state. The environment is this huge, complex thing, says Cleland. It's that interaction with this incredibly complex system that makes the quantum coherence vanish. Still, he says, there's plenty of reasons to keep trying to get large objects into quantum states. Large quantum states could tell researchers more about the relationship between quantum mechanics and gravity something that is not well understood. And quantum resonators could be useful for something, although Cleland admits he's not entirely sure what. There might be some interesting application, he says. But frankly, I don't have one now. References O'Connell, A. D. et al. Nature doi:10.1038/nature08967 (2010).
量子振动： 现有的技术条件下可以用激光把处于两个反射镜之间的超薄的振动薄膜（鼓膜）冷却到它的量子力学基态。（见图）。两篇理论文章预言一对振动薄膜可以像两个原子形成一个分子一样耦合起来，甚至能够演示纠缠。 薛定谔那只囚禁在生和死的量子叠加态上的猫是永远不可发生在现实中的。但是根据在2008年4日发表在 Physical Review Letters 和十月份发表在P hysical Review A 上的理论文章指出在不久的将来可以观测到另一种不同种类的宏观物体的量子效应一个在光腔中类似于鼓反射膜的振动。研究者证明了利用现有技术试验学家能够冷却一对这样的振动鼓膜到它们像一个两原子或者像一个纠缠态测量一个会立即影响另一个的状态。 奇怪量子行为对于电子或者分子是很普通的，但宏观物体并不具有。研究者通过论证大物体（特别是固态振动或者摇摆的系统）的量子行为以希望观察到从量子到经典的过渡。例如振荡的弹簧或单摆在原理上存在一个基态（即振幅最小的的状态）和一组就像原子的能级一样量子化的（不连续）的振幅。奇怪的量子预测是两个物体可以纠缠在一起，锁在同一个量子状态即不论两个物体相距多远测量一个会立即影响另一个的状态（这和相对论相矛盾），爱因斯坦嘲笑说这是距离的幽灵行为。 在今年三月来自Yale University 的 Jack Harris 和他的同事报道了一个用7cm的两端是镜子的光腔的实验。在光腔的中间他们悬挂了一个用厚度为50纳米的氮化硅做成的一平方毫米的薄膜（鼓膜）。这个薄膜（鼓膜）的表面能部分的反射并能自由的振动。Harris和他的团队试图利用一束激光照射光腔来冷却薄膜（鼓膜）到基态。那些因镜子和薄膜（鼓膜）反射阻塞的光子能够减少薄膜的振动而使其冷却到7微开（标准温度）的低温这是处于初始温度时振动的10，000分之一，但是还没有达到量子极限。 在 Physical Review A 上, 来自 在 Tucson now 的大学 Arizona 的Mishkat Bhattacharya and Pierre Meystre 更进了一步在理论上证明了一对这样的薄膜（鼓膜）可以形成一个类似分子的状态。他们把两个薄膜（鼓膜）中心对称的放入光腔并写下了他们的运动方程。因为两个鼓膜都和激光光子相互作用，所以就像用弹簧固定在墙上的两个物体被一个弹簧连接在一起而使它们有效地耦合在一起。这样产生不同振动频率的两个振动模式质心模（两个鼓膜的同向振动）和呼吸膜（两个鼓膜的反向振动） 带入实际的实验参数以后，研究者发现通过入射合适频率的激光这两个振动模式可以分别的被冷却。这两个鼓膜原子有效的结合成一个鼓膜分子，根据计算可以冷却到这个分子振动到它的基态。 来自Imperial College London 的 Michael Hartmann 和 Martin Plenio 在 Physical Review Letters 上发表文章证明应当可以制备这两个鼓膜长寿命的纠缠态。在他们的方案中这两个鼓膜以腔中心对称的放置，导致不同类型的振动模式。这个团队通过计算发现这两个振动模可以用两束激光同时冷却。 他们发现通过小心的选择激光频率，当模被冷却时，激光和鼓膜的相互作用恰好把两个鼓膜制备到它们的纠缠态。只要有激光纠缠态就存在。为了非破坏的验证纠缠，可以再用两束很弱的激光探测它们。来自Yale的Steven Girvin 和Harris在薄膜冷却方面合作。他认为这两个方案利用现在的实验技术能够在不久的将来在实验室里实现。他说：这是个能够产生很多神奇动力学的丰富的系统。 --Michelangelo D'Agostino 英文来自 http://focus.aps.org/story/v22/st16 参考文献: J. D. Thompson et al. , Strong Dispersive Coupling of a High-Finesse Cavity to a Micromechanical Membrane, Nature (London) 452 , 72 (2008) . Multiple Membrane Cavity Optomechanics M. Bhattacharya and P. Meystre Phys. Rev. A 78 , 041801 (issue of October 2008) Steady State Entanglement in the Mechanical Vibrations of Two Dielectric Membranes Michael J. Hartmann and Martin B. Plenio Phys. Rev. Lett. 101 , 200503 (issue of 14 November 2008)
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