r*****h
发帖数: 61 | 1 倒不一定是量化的人想出来的。
应给是做模拟的人先想出来这个概念的。
DFT的书里也会用到这个概念。
参考Richard M. Matin的Electronic Structure
另，两带电body间的相互作用能说的不确切。
因为两宏观带电体相互作用能做多极展开，只有第一项是Coulomb能。
后边是偶极能、四极能什么的multiple interaction energy项。 |
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f**d
发帖数: 768 | 2 这是一本计算神经科学的优秀著作，全文拷贝这里（图和公式缺），有兴趣的同学可以
阅读
如需要，我可以分享PDF文件（－－仅供个人学习，无商业用途）
From Computer to Brain
William W. Lytton
From Computer to Brain
Foundations of Computational Neuroscience
Springer
William W. Lytton, M.D.
Associate Professor, State University of New York, Downstato, Brooklyn, NY
Visiting Associate Professor, University of Wisconsin, Madison
Visiting Associate Professor, Polytechnic University, Brooklyn, NY
Staff Neurologist., Kings County Hospital, Brooklyn, NY
In From Computer to Brain: ... 阅读全帖 |
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A***n
发帖数: 8859 | 3 系数没有关系，但总力有
Coulomb friction, named after Charles-Augustin de Coulomb, is an approximate
model used to calculate the force of dry friction. It is governed by the
equation:
where
is the force of friction exerted by each surface on the other. It is
parallel to the surface, in a direction opposite to the net applied force.
is the coefficient of friction, which is an empirical property of the
contacting materials,
is the normal force exerted by each surface on the other, directed
perpendicular (norm... 阅读全帖 |
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n********g
发帖数: 6504 | 4 Original AI前线小组 AI前线 今天
作者｜Mikhail Dyakonov
译者｜李志
编辑｜Debra
AI 前线导读：爱好科幻小说的你，一定对量子计算并不陌生。而如今，备受瞩目的量
子计算到底进展如何呢？本文将带你走进当今的量子计算世界，听听理论物理学界大师
Mikhail Dyakonov 为什么不相信量子计算。
更多干货内容请关注微信公众号“AI 前线”（ID：ai-front）
插画作者：Christian Gralingen
当今，量子计算备受瞩目，风靡一时。每天，各种新闻媒体都争相报道这项高大上的技
术能为人类社会带来的神奇改变。然而，大多数评论家都忘记了——或者说有意掩盖了
这样一个事实：人们几十年来一直殚精竭虑地进行着量子计算研究，却到现在仍没有什
么实质性的应用展示出来。
有人说（相关文章：https://www.research.ibm.com/ibm-q/learn/what-is-quantum-
computing/）， 量子计算机可以“在许多学科中提供突破，包括材料和药物发现，复
杂人造系统的优化和人工智能”。还有人说（相关文章：https... 阅读全帖 |
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L*******o
发帖数: 895 | 5 1. Isaac Newton - English. Quantified and Qualified laws of motion and
gravity. Invented the reflecting telescope. Explained the concept of light
dispersion and co-invented the Calculus.
2. Albert Einstein - German/Swiss/American - Developed Theories of Special
and General Relativity. Described Brownian Motion. Nobel Prize winner for
his work on the photoelectric effect. Showed mass-energy equivalence.
3. Galileo Galilei - Italian - Discovered the law of Uniformly accelerated
motion. Improved on... 阅读全帖 |
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X******i
发帖数: 1384 | 6 物理：
Marie Curie
André-Marie Ampère
Henri Poincaré
Pierre-Simon Laplace
Blaise Pascal
Alfred Kastler
Edmond Becquerel
Charles-Augustin de Coulomb
Jean le Rond d'Alembert
Louis de Broglie |
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t**8
发帖数: 4527 | 7 杨28 唯一排上名的是活着的有名物理学家19 ， 在李政道之后，
其他的连前 50 名都排不上
Greatest physicist everThis is a featured page
In intellectual rankings, greatest physicist ever is an epitaph given to a
person, depending on ranking methodology, some rankings of which are listed
below, that classify, list, or describe someone as being the greatest
thinker in the field of physics of all time.
One of the more dominant surveys was the recent millennium poll on the
greatest physicist of all time, conducted by the British journal Phy... 阅读全帖 |
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o***s
发帖数: 42149 | 8 两名年轻女子周二在法庭上指控安省的一名男教师﹐说她们3人6年前一起有过性行为﹐
两人还以為男教师宠爱自己﹐对她们特別好。
据加通社消息，两个女子说﹐她们当年上学﹐一有空閒时间﹐就会到沃特福德高中学校
(Waterford High School)﹐进课堂找男教师库隆(Kristian Coulombe)。她们说﹐2000
年某一天﹐她们到学校找库隆﹐他邀请她们到他的寓所。那时候﹐她们不过10多岁﹐一
人15岁﹑另一人16岁。后来，她们一起和那名男教师在他的浴室和睡房发生了性行为。
两名女子表示，当时迷恋库隆﹐就像乐迷恋上摇滚巨星。女子的朋友较早前作证﹐指出
库隆不是她们的老师﹐没有教导她们﹐但是她们到课堂找他﹐他给她一种感觉﹐好像自
己「非常﹑非常」特別。
33岁的库隆被控性侵犯5名前女学生﹐对每一个女生犯了5项性剥削和性虐待罪行。 |
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o***s
发帖数: 42149 | 9 据星星生活报道，加拿大联邦统计局的周二公布的一份研究报告显示，尽管新移民所受
的教育程度比较高，但其收入状况比九十年代还要糟糕。也就是说，新移民的高学历并
不意味着高收入。
依据统计局的研究报告，在2002年，新移民在抵埠满一年的低收入比例比土生土长的加
拿大人高出3.5倍。两年之后的2004年，这个比率略有回落，为3.2倍。
报告说，这些数字比上世纪九十年代的任何年份都要高。在那个年代，新移民的低收入
率大致为本土加拿大人的3倍。
统计局的分析师说，最为担心的是，从公共政策角度看，那些最难于安居乐业的人士是
具有高学历、高技能的移民。
统计局说，现在加拿大所面临的贫穷已经不再是单身母亲领取社会福利地问题。在九十
年代，具有良好教育和技能的技术移民已经转换为持续贫穷的主体。如果要解决持续贫
困的问题，必须要了解构成这一群体的主体成分。
撰写该项研究报告的是联邦统计局的分析师加尼特-皮寇（Garnett Picot）、侯峰（
Feng Hou）和西蒙-库仑比（Simon Coulombe）。报告的题目是《近年移民群体持续低
收入及低收入的动态研究》（Chronic low income |
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c****s
发帖数: 5892 | 10 据加拿大驻华使馆提供的信息，第二届中国－加拿大科技合作联合委员会会议3月24日在北京召开，加拿大国家研究理事会主席库隆博（Dr. Pierre Coulombe）与中国科技部副部长曹健林共同主持了本次会议。
来自加拿大外交国贸部、工业部、自然资源部、农业与食品部、卫生研究院、驻华使馆及加有关省份驻华代表与中国科技部、环保部、中科院、国家自然科学基金委、中国驻加拿大使馆科技处及地方省市代表共60余人出席了本次联委会。
加方在本届联委会上表示，希望通过加中科技联委会平台，进一步加强两国在多个领域的合作与交流，优势互补、互惠互利，并愿与中方共同寻求多渠道科技合作项目。中方介绍了中国政府为应对金融危机带来的全球衰退，在科技促进经济增长、调整产业结构、增强自主创新能力方面采取的一系列政策措施，引起加方的极大关注。来自黑龙江、山东、上海及加拿大魁北克、安大略省的代表还介绍了两国友好省份间的科技合作进展。
会后，加拿大卫生研究院与中国科技部签署了合作谅解备忘录，启动了加中卫生健康研究合作计划。该计划的目标是为了进一步加强加拿大和中国共同关注的优先领域的卫生及医学的研究能力，以解决及减轻中加两国在主要 |
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a******o
发帖数: 16625 | 11 【 以下文字转载自 Military 讨论区 】
发信人: LindaLiao (梅影清吟), 信区: Military
标 题: 世界历史上最有成就的五十名物理学家。
发信站: BBS 未名空间站 (Sun Apr 8 17:18:35 2012, 美东)
1. Isaac Newton - English. Quantified and Qualified laws of motion and
gravity. Invented the reflecting telescope. Explained the concept of light
dispersion and co-invented the Calculus.
2. Albert Einstein - German/Swiss/American - Developed Theories of Special
and General Relativity. Described Brownian Motion. Nobel Prize winner for
his work on the photoelectric ef... 阅读全帖 |
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E********8
发帖数: 22 | 12 Then, it should not be a big deal. The novelty is perhaps the first
structrue solved using "Free electron laser".
About the radiation damages, they are always there, which is physics.
However, if ultrashort x-ray pulse is used, one can record a "radiation-damage-free
" picture before coulomb explosion.
monster breakthrough.
need to struggle to get crystals. As to the phase issue, LZ did not mention
it, I think they use molecular replacement. Otherwise I can't imagine a
stronger beam source will |
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l**********1
发帖数: 5204 | 13 空气是不好 MM还是比北京多的 魔都嘛
不过要是cs的微软的都被硬盘了
以下的Bio Cs PD 除非以后进医院 MD 后才能稳拿吧 当然O8 的医改
把美中的博士屯和 浦东陆家嘴的 MD的年收入 都税前的 以欧元换算后
扯平了的话
one example:
Postdoc Positions, Computational Research
Shanghai Jiao Tong University
Postdoctoral positions in computational research at SJTU
Institute of Natural Sciences (INS) – a newly established interdisciplinary
institute at Shanghai Jiao Tong University (SJTU) http://ins.sjtu.edu.cn to conduct first-rate research in natural and engineering sciences, is recruiting Ins... 阅读全帖 |
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C********5
发帖数: 194 | 14 From Coulomb's law and W=Fdr |
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b**u
发帖数: 17 | 15 这里列的是我知道的一些原Bourbaki成员名单. 肯定不全.
Henri Cartan, Claude Chevalley, Jean Delsarte, Jean Dieudonn'e,
Ren'e de Possel, Andr'e Weil, Charles Ehresmann, Szolem Mandelbrojt,
Jean Coulomb,
Armand Borel, Samuel Eilenberg, Serge Lang, Saunders Mac Lane,
Claude Chabauty, Jacques Dixmier, Pierre Cartier, Jean-Pierre Serre,
Roger Godement, Laurent Schwartz, Pierre Samuel, Michel Demazure,
Francois Bruhat, Jean Giraud, Bernard Malgrange, Jean-Louis Koszul,
Charles Pisot, Jean-Loui Verdier, Adrien Douady, Alexan |
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w******t
发帖数: 107 | 16 请教版上搞电化学的兄弟：
在cycle多孔碳材料（amorphous）的时候，用什么样的电解液合适呢？
用1M LiClO4/EC/DMC(1:1 v/v)与用LiPF6/EC/DMC(1:1 v/v)有显著性区别吗？看书上说
LiPF6形成的SEI layer更致密。我曾经用过1M LiClO4/PC，但是发现cycleability不太
理想，而且Coulombic efficiency也没有在最初几个循环中超过90%。在第一个charge
过程中，在0.9V (vs. Li+/Li)处有一个很大的平台，我想是PC（和LiClO4）分解导致
的吧？可是看书上和文献中都说，PC可以用作amorphous carbon anode的电解液。咋回
事呢？谢谢了先！ |
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w****1
发帖数: 4931 | 18 As far as I understand the quantum critical theory is described by a CFT
that connects a Higgs phase to a Coulomb phase. It is described by the IR
fixed point of a (fined tuned) gauge theory rather than a Wilson-Fisher type
fixed point. "Simple" field theories are often the hardest to solve. Highly
supersymmetric field theories look complicated but are easy to solve.:) |
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C**R
发帖数: 1047 | 19 please calculate how strong a B field u need to bend the proton as much as
you need to bend a electron with the same velocity and the same curvature.
then, u will give up considering proton.
the only reason that i can think of is that the coulomb blur effect (also
called space charge effect) is smaller for protons. You don't loose too much
temporal resolution while ur bunch of protons travel a long way. If you are
not doing ultra-fast, space charge effect is ignorable (hopefully).
please read ja |
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h*******e
发帖数: 288 | 20 网上找到相关的，但是找不到最基本的概念，公式。哪位指点一下。万分感谢！ |
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e**********n
发帖数: 359 | 22 A terminology to confuse people. |
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o***k
发帖数: 23 | 25 V Ernst 1978 J. Phys. A: Math. Gen. 11 311-339 doi: 10.1088/0305-4470/11/2
/010
A quantum theory of the self-energy of non-relativistic fermions and of the
Coulomb-Yukawa force acting between them
thanks a lot ! |
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m*******s
发帖数: 3142 | 26 I find that some book e.g. Many-body theory of solids by John C. Inkson P145
says that :" By analogy with the classical polarization, we define a
polarization
propagator through the relationship ... ε=1-vP" , where ε is the
dielectronic response function, and v is the bare Coulomb potential.
I do not remember such relationship in electrodynamics. Can anybody remind
me of it?
In fact, on the next page in the book, I find a new relationship i.e. P=δρ
/δV， where V is the total potential instead of |
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c****e
发帖数: 2097 | 27 both a pretty elementary, due to pauli exclusion principle you may say.
1) splitting of degenerate states by spin coupling/pairing
2)coulomb repulsion (of protons) compared with fermi levels of neutrons (is that the right name?) |
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c*********n
发帖数: 305 | 28 就是Coulomb staircase (single electron transfer)的模拟软件 不知道那里有免费
下载的？ 谢先！ |
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c**m
发帖数: 1632 | 29 Acoustic phonons close to the long wavelength limit. Rough estimation gives
2*pi*Vs/kB*T and that's why they talked about breather mode of the HTc
ceramics. From my perspective, not so much physics there. The mechanism of
HTc superconductivity is the "coulomb-repulsion induced electron coherent
state" though the exact model is not available. "Phonon assisted pairing
mechanism" works for low temperature superconductors and it could not
explain the phase transition in chemical stoichiometry. |
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b******r
发帖数: 45 | 30 Of course gauge symmetry can be unbroken. But that's not my point. My point
is that you can't explicit break it without introducing new degrees of freed
om. For the case of un-gauged symmetries, you can do that by simply tuning s
ome charges off.
In QED, I can just work in the Coulomb gauge and forget about the U(1) gauge
symmetry. The U(1) symmetry is introduced only for mathematical convenience
. |
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Q******g
发帖数: 607 | 31 that's right. Coulomb gauge in QED is physical. of course, it's
mathematically harder and uglier to quantize it in this
non-covariant gauge. but it is doable. In fact, one can even do it
for QCD. It is much more uglier and complicated. One reference
for such kind of treatment is TD Lee's QFT book.
part
exis
the
sho
th
and
physi
spin |
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c********6
发帖数: 658 | 32 本人早年在国内上过普通物理，近期修了一门nuclear physics,感觉不难，但是对
Electromagnetism这门课不了解，这门课需要那些数学知识？ 太难的话就不上了。
谢谢！！
Electromagnetism:
The laws of electricity and magnetism are developed using the language of
vector calculus. Topics include: Coulomb’s Law, the electrostatic field and
potential, Gauss’ Law, dielectrics, capacitors, electric current, the
steady magnetic field, Biot Savart Law, Ampere’s Law, magnetic materials,
Faraday’s Law, the displacement current, Maxwell’s Equations, and plane
electromagnetic wave... 阅读全帖 |
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l***y
发帖数: 1166 | 34 转载不代表本人意见，有人是这么认为的：
《電磁波的機理》的信件回复
電磁波的機理是表面力場的共振接替，好比是接力賽，這是很基礎的物理知識。一百五
十年前的法拉第（Michael Faraday 1791-1867）就已經非常清楚電磁波的機理，所以
他能總結並發明電磁感應定律，而在二百年前的奧斯特（Hans Christian Oersted
1777-1851），也了解到這個機理，甚至連更早的庫倫（Charles Augustin de Coulomb
1736-1806）也發現了這個現象，只是沒有做出總結，而這個科學知識已經三百年之久
，結果中國的學生到今日還不清楚，甚至博士生也完全搞不清楚。
你或許會認為電磁波不用介質也能運動，這就是愚民，是非常幼稚的愚民，而這是
三百年前的科學知識，是哥白尼時代的科學知識，卻是新中國的科普教材。
這一切的亂象都是被相對論害的，被美國政府的教科書害的，因為中國使用的教科
書全部都繼承自美國政府旗下的科學家所亂寫的，全部使用帝國主義的資料去刪改的，
國內的論文，全部抄襲帝國主義者提供的公開論文，沒有機密性質的論文，所以全是這
些愚民東西，不斷的被繼承... 阅读全帖 |
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r*f
发帖数: 731 | 35 A Party of Famous Physicists
One day, all of the world's famous physicists decided to
get together for a tea luncheon.
Fortunately, the doorman was a grad student, and able to
observe some of the guests...
Everyone gravitated toward Newton, but he just kept
moving around at a constant velocity and showed no reaction.
Einstein thought it was a relatively good time.
Coulomb got a real charge out of the whole thing.
Cavendish wasn't invited, but he had the balls to show up anyway.
Ca |
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