T**m
发帖数: 142 | 1 I am not an expert in the field of Jacob Lurie. Here is my impression:
His work is of foundational nature in the same way category theory connects
different kinds of mathematics. This new theory allows ideas of homotopy
theory to enter into other areas of mathematics, such as algebraic geometry,
moduli problems in differential geometry, and a lot more... |
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m***c
发帖数: 1177 | 2 畅想未来的话：推荐这篇日志的原因很简单，给所有期望在学科研究上能有所建树的学
子们一面镜子，镜子里不仅有这位昔日的IMO金牌、北大数院毕业后前往MIT攻读博士后
、29岁拿到拉马努金奖、现在Stanford做Assistant Professor的大神恽之玮，还有比
利时数学家Pierre Deligne（皮埃尔·德利涅）以及德国数学家Gerd Faltings (格尔
德·法尔廷斯)和Peter Scholze等大神的影子，更为重要的是，作者揭示了大神之所以
能称为“大神”，背后所付出的一切，同时又用一个个鲜活的事例演示了现代版的“山
外有山”的典故。本文来自人人网“冷雪霏的日志”，感谢作者给我们提供了恽之玮的
近况。
为什么我总是低估YUN神
作者的话：一直都知道YUN神强，无以伦比的强，但总是发现他比我想象的还强。最后
我终于发现是我对“强”的定义太局限了，不知道人原来是可以强成这样子。
[转载]学友眼中的大神——恽之玮究竟有多强
恽之玮
YUN神究竟有多强
其实YUN神有多强这个问题，从大学起一直都在... 阅读全帖 |
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m***c
发帖数: 1177 | 3 畅想未来的话：推荐这篇日志的原因很简单，给所有期望在学科研究上能有所建树的学
子们一面镜子，镜子里不仅有这位昔日的IMO金牌、北大数院毕业后前往MIT攻读博士后
、29岁拿到拉马努金奖、现在Stanford做Assistant Professor的大神恽之玮，还有比
利时数学家Pierre Deligne（皮埃尔·德利涅）以及德国数学家Gerd Faltings (格尔
德·法尔廷斯)和Peter Scholze等大神的影子，更为重要的是，作者揭示了大神之所以
能称为“大神”，背后所付出的一切，同时又用一个个鲜活的事例演示了现代版的“山
外有山”的典故。本文来自人人网“冷雪霏的日志”，感谢作者给我们提供了恽之玮的
近况。
为什么我总是低估YUN神
作者的话：一直都知道YUN神强，无以伦比的强，但总是发现他比我想象的还强。最后
我终于发现是我对“强”的定义太局限了，不知道人原来是可以强成这样子。
[转载]学友眼中的大神——恽之玮究竟有多强
恽之玮
YUN神究竟有多强
其实YUN神有多强这个问题，从大学起一直都在... 阅读全帖 |
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s****s
发帖数: 4 | 4 The role played by science in human being's development is obvious, and
China's lack of it, especially in modern times is puzzling. But once you
take a deeper look at some scientific developments in recent history,
including those in early twentith century in both China and Japan, the
importance of leading figures immediately manifest itself.
One might argue the importance of "tradition". But so called "tradition" is
essentially another expression for dominant leading figures, its community
and ... 阅读全帖 |
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h*h
发帖数: 27852 | 5 【 以下文字转载自 Military 讨论区 】
发信人: hsh (nidaye), 信区: Military
标 题: 莫宗坚谈张益唐：张没有找莫要推荐信
发信站: BBS 未名空间站 (Thu Jun 2 15:59:38 2016, 美东)
Zhang, Yitang’s life at Purdue
(Jan. 1985-Dec, 1991)
T.T.Moh1
Dr. Zhang Yitang made a major advancement to the twin prime conjecture
as verified by Prof. H. Iwaniec, a famous number theorist. This is a
historic result. I congratulate Dr. Zhang, Yitang.
The concept of prime nummbers started with Greek mathematics. Euclid
shown that there were infinitly many primes. We may... 阅读全帖 |
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O***p
发帖数: 1333 | 6 CFD helps determin the convection HTC for the geometry. I did modeling in
Patran and I had to manually input the convection coefficient for the
geometry, which I hated so much because you know how difficult that is to do
with a finned heat sink, and when you have a pin-fin array heat sink, just
forget it.
Conduction only applies within the package. Convection and radiation is the
way to remove heat into ambient air. That's why I think CFD software is needed
conduction.
电的
，比
果有 |
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f*******r
发帖数: 204 | 12 我不确定，不过猜起来可能就是正交固定坐标系和非正交的坐标系，比如曲面坐标系 |
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b***2
发帖数: 5 | 14 Call for Ph.D. Student
Position: Ph.D. student (research assistant) in mechanical engineering.
University: Tennessee Technological University, Cookeville, Tennessee, USA
Advisor: Kwun-lon Ting (ASME fellow) http://www2.tntech.edu/me/Faculty_Bios/ktingbio.html
Financial aid: Research assistant ship starting $1300/month (renewable
annually) plus all tuitions and fees
Starting time: As early as possible
Area of research: computer aided geometry design, kinematics, linkages/
gearing... 阅读全帖 |
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d********e
发帖数: 198 | 15 Journal of Lubrication Technology
April 1968
Volume 90, Issue 2
“The Effects of Geometry and Inertia on Face Seal Performance—Laminar Flow”
H. J. Sneck
pp. 333-341
“The Effects of Geometry and Inertia on Face Seal Performance—Turbulent
Flow"
H. J. Sneck
pp. 342-350
Email: w********[email protected]
多谢多谢！！ |
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w*********y
发帖数: 10 | 16 Postdoctoral position in artificial two-dimensional materials
BC: 68606
The Fondazione Istituto Italiano di Tecnologia – IIT (www.iit.it) - was
founded with the objective of promoting the country's technological
development and further education in science and technology. In this sense
IIT is committed to achieving its scientific program, which sees in the
integration between basic scientific research and the development of
technical applications a major inspirational principle. The research
pro... 阅读全帖 |
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k*********g
发帖数: 791 | 17 原来那个写了一本非常好的“calculus”书的，是个做differential geometry的；
相信他的书都写得很好；
不过，原本以为场论里面都是代数，both classical linear space algebra and
modern abstract algebra；
没想到，又是geometry，跟广义相对论很相似？
需要 albegraic topology，differential topology？
数学太乱了；
物理世界真的有这么复杂码？？ |
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b***2
发帖数: 5 | 18 【 以下文字转载自 ME 讨论区 】
发信人: byu42 (william), 信区: ME
标 题: call for PhD student
关键字: 博士,招生,机械
发信站: BBS 未名空间站 (Tue Mar 1 11:44:16 2011, 美东)
Call for Ph.D. Student
Position: Ph.D. student (research assistant) in mechanical engineering.
University: Tennessee Technological University, Cookeville, Tennessee, USA
Advisor: Kwun-lon Ting (ASME fellow) http://www2.tntech.edu/me/Faculty_Bios/ktingbio.html
Financial aid: Research assistant ship starting $1300/month (renewable
annually) plus all... 阅读全帖 |
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e*******n
发帖数: 4912 | 19 1.在这个系列里我打算写一些我在各种文章和书中看到的八卦
希望能博大家一笑
有一次littlewood问hardy,为什么他每次到一个旅馆就会把镜子用毛巾盖起来?
回答是:因为他长得太丑了
2.Hadamard,Jacques去意大利Bologna开1928年国际数学家大会,期间要坐火车去一个地
方
车厢里有很多人在聊天,他觉得十分累,就出了道困难的数学题,众人思考这道题,
车厢里马上安静下来了,于是Hadamard就可以睡觉了
3.Bourbaki是一个法国数学家的集体代名词
Bourbaki的第一篇文章发表在comptes Rendus(法国科学院的一个杂志)上
在1949年Journal of symbolic logic上的一篇文章
"Foundations of mathematics for the working mathematican"
中,Bourbaki教授的地址是University of Nancago
一个杜撰的地址,分别是Nancy和Chicago(weil在那里)前后组合
1940年,Boas,Ralph(MR的主编)曾经在Encyclopa... 阅读全帖 |
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s****s
发帖数: 4 | 20 The role played by science in human being's development is obvious, and
China's lack of it, especially in modern times is puzzling. But once you
take a deeper look at some scientific developments in recent history,
including those in early twentith century in both China and Japan, the
importance of leading figures immediately manifest itself.
One might argue the importance of "tradition". But so called "tradition" is
essentially another expression for dominant leading figures, its community
and ... 阅读全帖 |
|
发帖数: 1 | 21 【 以下文字转载自 Military 讨论区 】
发信人: tranquilan (zhutou), 信区: Military
标 题: 中国科学家吴岳良发表物理学终极理论论文，为爱因斯坦之谜打开新窗口
发信站: BBS 未名空间站 (Sat Jan 27 14:30:24 2018, 美东)
中国科学家吴岳良发表物理学终极理论论文，为爱因斯坦之谜打开新窗口
据中科院官方网站报道，中国科学院院士吴岳良在物理学大统一理论上实现重要突破。
报道称，吴岳良在揭秘爱因斯坦统一场论的研究中取得突破，创建了超统一场论（
hyperunified field theory）。该理论受相对论性狄拉克旋量理论、爱因斯坦广义相
对论、杨-米尔斯规范理论和大统一理论的启发，并基于吴岳良前期发展的引力量子场
论的研究成果，为揭示爱因斯坦统一场论理念中的不解之谜，探索终极统一理论打开了
一扇新窗口。
中国科学院院士吴岳良
众所周知，中国在物理学终极理论领域，同世界顶级水平还存在着较大差距，那么，吴
岳良院士的理论究竟处于什么水平？
吴岳良院士这次的研究成果是发表在《欧洲物理杂志C》上。据观察者网查询，《欧洲
... 阅读全帖 |
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r**a
发帖数: 536 | 22
JF
return
这个当然算了，比如SABR model。实际上SABR里面的技术非常universal。只要你不怕
麻烦，你可以用它来算更一般的SV模型。问题在于，并不是什么SV模型都能有closed
form asymptotic expansion的。在SABR里，核心是那个heat kernel on poincare
plane。正是因为这个玩意有closed form，这样才有Hagan的asymptotic expansion。
你的SV模型如果对应的Riemannian Geometry不是poincare geometry。那么you are
probability in trouble.
另外一点是要看你模型如何用。比如如果你要price一个20年的option，你要问一下你
自己你的formula这时候能不能用。效果怎么样。这些都要做test的。
实现起来也 |
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L*******t
发帖数: 2385 | 23 不会转发帖子，只能硬贴过来了。。。。
发信人: Leinhardt (Leinhardt), 信区: Mathematics
标 题: 求版上大牛推荐微分几何的书或者Notes
关键字: Differential Geometry
发信站: BBS 未名空间站 (Sat Aug 23 14:17:04 2014, 美东)
我想系统性地重温和学习如下知识：
Differential manifolds
Tangent Space and Cotangent Space
Connections, Lie Group and Lie Algebra
Principal Fiber Bundle and related Geometry
Homotopy
Gauge Theory
我以前是学黎曼几何的，可惜荒废太久，希望以上的概念和知识都是从数学的角度入手
：）
请版上大牛推荐一些书和Notes吧，有PDF最好啦！ |
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r**a
发帖数: 536 | 24 same feeling here.
If you are interested in the detailed derivation of Hagan's SABR model, it
is helpful. However, if you are trying to apply this kind of tech to other
real models, you will meet many problems. The framework of geometry and
stochastic process had been done long long time ago. The first difficulty
you are facing is the close-form solution of heat equation on manifold
corresponding to the SDE system, if you want to apply this tech in reality.
The close-form solution of heat equati... 阅读全帖 |
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a**u
发帖数: 99 | 25 What is theoretical physics?
Algebra and geometry were good for describing size, but not for
describing motion, so Newton invented calculus.
Theoretical physicists use mathematics to describe certain aspects of
Nature. Sir Isaac Newton was the first theoretical physicist, although
in his own time his profession was called "natural philosophy".
By Newton's era people had already used algebra and geometry to build
marvelous works of architecture, including the great cathedrals of
Europe, but alg |
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g***e
发帖数: 9 | 26 Seems you are studying general relativity or string theory?
If you have learned the basic math in college, i.e. real analysis
and complex analysis, linear algebra, differential equaitons... you'd
better start with Lie group and Lie algebra, which are very important
in particle physics. For geometry I think you need know something about
topology first, then differential manifold and Riemann geometry. The fibre
bundle theory is very useful in physics and you also need know a little
bit of inde |
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y***u
发帖数: 25 | 27 I forgot to mention about the math foundation of string.
Besides what you have learned, geometry is very helpful. K. Nakahara's
<> is excellent. But to be honest, I only read
a few chapters. I also need to learn more goemetry. Studying string is really
a hard job, at least to me. Probably because I am too dumb. And there is even
no good and updated text book. I don't like Polchinski's book. Fortunately,
there will be an excellent text book appears soon (maybe half |
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a***u
发帖数: 72 | 28 Mathematics: The reluctant celebrity
A reclusive Russian claims to have solved a century-old mathematical problem
— but his enigmatic personality is adding a fresh dimension to the
proof-checking process. Emily Singer reports.
C. GUNN & S. LEVY, GEOMETRY CENTER, UNIV. MINNESOTA
Proving the Poincaré conjecture will offer fresh insight into
three-dimensional geometry.
It takes guts for a young Russian to stride into the heart of the US
mathematical establishment after claiming to have solved a pro |
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R*****s
发帖数: 41236 | 30 http://www.nytro.com/index.cfm/nytro-blog/the-new-cervelo-p5-co
nytro/
At Cervelo, aerodynamics benchmarks are meant to be reset. And they are
doing it once again with the one tri bike you've been waiting for - The new
Cervelo P5
The much anticipated lauch in 2011 has been pushed back to perfect and make
some final tweeks. Worth the wait? Definitely. Continuing Cervelo's pack
leading position in triathlon and TT bikes, the new P5 will arrive not just
pushing the technological envelope by tearing... 阅读全帖 |
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i*********5
发帖数: 19210 | 31 来自主题: _Triathlon版 - 购车求建议 Triathlon Bike or Road Bike?
http://www.beginnertriathlete.com/cms/article-detail.asp?articl
Tri-specific bikes
Tri bikes also handle well but in a different way. Tri bikes are made to go
fast while utilizing rider energy efficiently and even conserving energy to
some extent (remember – the bike is only 1/3 of the race). In order to
accomplish this, tri bike geometry has a steeper seat tube angle, usually 76
-78 degrees. The head tube angle is usually a little less aggressive, the
top tube is sl... 阅读全帖 |
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S*********g
发帖数: 24893 | 32 【 以下文字转载自 StephenKing 俱乐部 】
发信人: StephenKing (金博士), 信区: StephenKing
标 题: 不系安全带，John Nash今天车祸死了
发信站: BBS 未名空间站 (Sun May 24 11:17:59 2015, 美东)
John Forbes Nash, Jr.
Born June 13, 1928
Bluefield, West Virginia, U.S.
Died May 23, 2015 (aged 86) [1]
Residence United States
Nationality American
Fields
Mathematics
Economics
Institutions
Massachusetts Institute of Technology
Princeton University
Alma mater
Princeton University
Carnegie Institute of Te... 阅读全帖 |
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p*********e
发帖数: 32207 | 33 ☆─────────────────────────────────────☆
pandamalone (0000~史前圣灵猫熊) 于 (Wed Oct 21 02:30:51 2009, 美东) 提到:
【 以下文字转载自 Automobile 讨论区 】
发信人: doubleswords (=>>双剑>>: 姚明=宇宙第一中锋), 信区: Automobile
标 题: Lexus 终于推出 超级跑车了 LFA
发信站: BBS 未名空间站 (Wed Oct 21 01:58:45 2009, 美东)
好久不来这里逛了，今天看了一下东京的车展新闻
这车已经拖得太长时间，基本都失去关心兴趣了，全球 500 辆 $400K的价格就更没意
思了。也就下个月的 LA 车展上扫两眼了。只是希望这个发动机能用在普通 Toyota 上
面。整车里面不错，外面特别是前脸一般般。
* 4.8-liter 72-degree V10 putting out 560 hp at 8,700 RPM (that's 116.5
hp/liter) and 354 lb.-ft. o... 阅读全帖 |
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w*******y
发帖数: 60932 | 34 Link:
http://www.amazon.com/gp/product/B002EL32US/ref=s9_simh_gw_p309
Lowest price I've ever seen for these. Bought them a few months back at $58,
also from amazon. The $48.46 model is the polished black frame/gray lenses.
Pretty nice, but the matte black frame with iridium lenses are my favorite.
NOT POLARIZED!
If the world wasn't made to fit you, you're in good company. The legends of
action sports go through life reveling in originality and crushing
conventional ideas beyond recognition. If o... 阅读全帖 |
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q********g
发帖数: 10694 | 35 Sobereva
Department of Chemistry, University of Science and Technology Beijing,
Beijing 100083, China
前言：本文主要介绍过渡态、反应路径的计算方法，并讨论相关问题。由于这类算法极
多，可以互相组合，限于精力不可能面面俱到展开，所以只介绍常用，或者实用价值有
限但有启发性的方法。文中图片来自相关文献，做了一定修改。由于本文作为帖子发布
，文中无法插入复杂公式，故文中尽量将公式转化为文字描述并加以解释，这样必然不
如公式形式严谨，而且过于复杂的公式只能略过，但我想这样做的好处是更易把握方法
的梗概，有兴趣可以进一步阅读原文了解细节。对于Gaussian中可以实现的方法，文中
对其在Gaussian中的使用进行了一些讨论，希望能纠正一些网上流传的误区。虽然绝大
多数人不专门研究计算方法，其中很多方法也不会用到，但多了解一下对开阔思路是很
有好处的。
文中指的“反应”包括构象变化、异构化、单分子反应等任何涉及到过渡态的变化过程
。“反应物”与“产物”泛指这些过程的初态和末态。“优化”若未注明，... 阅读全帖 |
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i**e
发帖数: 19242 | 36 by unschoolingmom
声明一下，不是所有人适合或者愿意unschooling的。我自己也在学习过程中，时间和
论坛气氛允许的情况下，分享一下自己的学习经历。有兴趣留痕，无兴趣飘过。：）
How can I stop my children from learning?
on Sunday, July 4, 2010 at 2:53am
Seriously, I cannot stop my children from learning!
I have been looking into unschooling for a little bit more than a year. In
the last 14 months,
I have read over 50 books on related subjects
I have subscribed and read a couple of unschooling mailing lists for one or
two hours everyday
I have attended my first unschooling... 阅读全帖 |
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s******o
发帖数: 298 | 37 March 15, 2002 | During the mid-1970s, fortuitous geometry allowed Mariner 10
to zip by Mercury three times in a 12-month period. But that same geometry
precluded the spacecraft from seeing almost half of the innermost planet's
surface — a "terra incognita" that remains virtually unknown nearly three
decades later.
However, as radar facilities on Earth continue to probe the unseen territory
with ever-improving resolution, Mercury is slowly giving up its secrets.
Several days of observations made |
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C*********e
发帖数: 587 | 38 全世界还都在用欧几里德的geometry了，这个绝对比牛顿的微积分之类的用得更多，那
怎么不把希腊的学校一把推上去？ |
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m**********e
发帖数: 12525 | 39 可怜的奥数金牌，知识就永远停留在了大一的数学分析上面，
有时间看看alain connes的大作去吧
发信人: mifepristone (弃婴), 信区: Military
标 题: Re: 时间是连续的吗？
发信站: BBS 未名空间站 (Thu Jan 24 21:19:25 2013, 美东)
一帮外行上窜下跳
这个问题，早已经研究了几十年了，其实就是x,t满足不对易李代数，数学上叫做
noncommutative geometry,如果有兴趣看看数学家的作品：
http://www.alainconnes.org/docs/book94bigpdf.pdf
如果觉得太深奥，也可以看看物理学家的作品：
http://rmp.aps.org/abstract/RMP/v73/i4/p977_1
一句话，因为引力常数太小，所以如果spacetime是quantization的话，李代数的结构
常数不是量子力学里面的planck常数，而是比planck小几十个数量级的常数，所以除非
能达到比big bang的planck scale还高无数倍的能级，否则在理论上讨论都是毫无意义
的... 阅读全帖 |
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c***s
发帖数: 70028 | 40 物理学家一直在寻求能够统一所有物理学的那个终极理论。现在看来，他们或许不得不止 步于一组理论，无法将它们合为一体。
霍金：真实世界的“真实”
物理学家一直在寻求能够统一所有物理学的那个终极理论。现在看来，他们或许不得不止 步于一组理论，无法将它们合为一体。
撰文 斯蒂芬?霍金（Stephen Hawking）
莱昂纳德?蒙洛迪诺（Leonard Mlodinow）
几年前，意大利蒙扎市议会通过了一项法案，禁止市民将金鱼养在圆形鱼缸里观赏。提案者解释说，把金鱼关在圆形鱼缸里非常残忍，因为弯曲的表面会让金鱼眼中的“现实” 世界变得扭曲。抛开这一法案给可怜的金鱼带来的福祉不谈，这个故事还提出了一个有趣的哲学问题：我们怎么知道我们感知到的“现实”是真实的？金鱼看见的世界与我们所谓的“现实”不同，但我们怎么能肯定它看到的就不如我们真实？据我们所知，就连我们自己说不定终其一生，也在透过一块扭曲的镜片打量周遭的世界。
在物理学中，这个问题并非纯理论空想。实际上，物理学家和宇宙学家发现他们自己眼下的处境和金鱼差不多。数十年来，我们一直上下求索，渴望得到一个终极的万有理论，可以用一套完备自洽的基本定律来... 阅读全帖 |
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c*********5
发帖数: 5813 | 41 这家伙难道是big bang里人物的原型？
昂纳德?蒙洛迪诺是美国加州理工学院的理论物理学家。他写过 7 本科普著作，包括《
欧几里德之窗：从平行线到超空间的几何历 程》（Euclid’s Window: The Story of
Geometry from Parallel Lines to Hyperspace）和《醉汉晃悠悠：随机性如何决定我
们的生活》（The Drunkard’s Walk: How Randomness Rules Our Lives）。他还为《
百战 天龙》（MacGyver）和《星际迷航：下一代》写过剧本 |
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L*********d
发帖数: 7037 | 42 此几何非彼几何。不会认为曹操是讲geometry吧。 |
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i*****s
发帖数: 4596 | 43 丘成桐：从明治维新到二战前后中日数学人才培养之比较
序言
在牛顿（1642～1727）和莱布尼茨（1646～1716）发明微积分以后，数学产生了根本性
的变化。在18到19世纪200年间，欧洲人才辈出，在这期间诞生的大数学家不可胜数，
重要的有：尤拉（Euler，1707～1783），高斯（Gauss，1777～1855），阿贝尔（Abel
，1802～1829），黎曼（Riemann，1826～1866），庞卡莱（Poincare，1854～1912）
，希尔伯特（Hilbert，1862～1943），格拉斯曼（Grassmann，1809～1877），傅立叶
（Fourier，1768～1830），伽罗华（Galois，1811～1832），嘉当（E.Cartan，1869
～1951），伯努利（D. Bernoulli，1700～1782），克莱姆（G. Cramer，1704～1752
），克莱罗（A. Clairaut，1713～1765），达朗贝尔（d’Alembert，1717～1783），
兰伯特（J. Lambert，1728～1777），华林（E. Waring，1... 阅读全帖 |
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S**********b
发帖数: 3142 | 44 我读EUCLID’S ELEMENTS OF GEOMETRY
就在想难道那些线啊角啊不能用中国字表示么？
那几条公理难道不能用中国文字表达么？
公理体系难道不是通过思维想象出来的？
想象力难道被中国的方块字就压抑了不得解放？ |
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S**********b
发帖数: 3142 | 45 Imagine the geometry of four-dimensional space done with a view to learning
about the living conditions of spirits. Does this mean that it is not
mathematics? |
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c***r
发帖数: 4631 | 46 "中间有一个大写的g字， 共济会自称其含义是推动世界向光明的方向发展"
我叉，这么多年一直以为是Geometry的意思，原来是“光明”的意思。 |
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s**********t
发帖数: 2401 | 47 操蛋的玩意儿永远是操蛋的玩意儿，本质改不了，就算是四五代还是这样。
中世纪以来欧洲贵族脑子里在想什么？数学符号，哲学术语，和音律。
四艺 arithmetic, geometry, music,astronomy对他们来说都是基本功。
天朝的这帮玩意儿，身边要么不是妓院老鸨，金融骗子，就是军界痞子，算是这个社会
的渣滓总稽核 |
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k*******1
发帖数: 526 | 48 您哪儿看出我没搞清什么是应力来的？你回答我这个问题，我对应力的理解怎么错的？
先说应力：假设一个bar吧，有axial load P
sigma = P/A
P就是载荷，A是面积。
我这个理解有错吗？您如果认为错了，你说说说你的理解，写出个公式来。
应力集中，stress concentration,就是局部应力比较高，有可能是由于集中载荷造成
的，就好比锤子砸在石板上，在锤子接触石板的地方，应力集中，而远离接触点/面的
位置，应力逐渐下降。还有一种可能是由于geometry造成的，比如一个铁板，中间有个
空，在外力载荷下，孔附近的应力较高。
好，你不是要我用ansys算吗，我会的，我现在没有license，两个license 都在run
job.等我有了license,也就10分钟的事儿。我会把结果贴出来的。 |
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s******r
发帖数: 5309 | 50 You need to read more, and you will know, I don't have a year to teach you.
Can you teach a 5 year old
differential geometry in one day? LOL |
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