I’m doing a (free) operating system (just a hobby, won’t be big and professional like gnu) for 386(486) AT clones.
— Torvalds, Linus (1991-08-25). Post to comp.os.minix newsgroup. Retrieved on 2006-08-28.
— Notes: This was the launch of Linux.
2012.04.22 Sunday ACHK
The most powerful illusion, 3
The biggest problem we have as human beings is that we confuse our beliefs with reality.
— Alan Kay
Reality is that which, when you stop believing in it, doesn’t go away.
— Philip K. Dick
2012.04.22 Sunday ACHK
這段改編自 2010 年 3 月 20 日的對話。
留意，這個「軟硬智力」比喻，不可用得太盡，因為，「人腦硬件」和「電腦硬件」，有一個核心的分別。
人腦的軟件是思想。人腦的硬件是一大堆腦細胞，即是「神經元細胞」。人腦可以通過增加和增強神經元細胞之間的聯繫，來提升運作效能。電腦的硬件則不會自我改變。改進電腦硬件的唯一方法是，把它更換掉。
— Me@2012.04.22
2012.04.22 Sunday (c) All rights reserved by ACHK
時空幻境 3
Portal is a 2007 single-player first-person puzzle-platform video game developed by Valve Corporation.
The game primarily comprises a series of puzzles that must be solved by teleporting the player’s character and simple objects using “the handheld portal device”, a device that can create inter-spatial portals between two flat planes.
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| By Kaini [CC-BY-SA-3.0], from Wikimedia Commons |
The game’s unique physics allows momentum to be retained through portals, requiring creative use of portals to maneuver through the test chambers.
— Wikipedia on Portal (video game)
2012.04.21 Saturday ACHK
Process, not a state, 6
Perseverance is not a quality, but an effect
of keeping doing your best “now and here”,
whatever the past and future.
— Me@2012-04-05 12:24:36 PM
2012.04.21 Saturday (c) All rights reserved by ACHK
Weak isospin is to the weak interaction what electric charge is to the electromagnetism, and what color charge is to strong interaction.
— Wikipedia on Weak interaction
2012.04.20 Friday ACHK
Those that can, do. Those that can’t, complain.
— Torvalds, Linus (2003-09-23).
— Post the Linux Kernel Mailing List.
— Retrieved on 2007-06-26.
2012.04.20 Friday ACHK
軟硬智力 5.5
這段改編自 2010 年 3 月 20 日的對話。
（安：根據你剛才的比喻，「硬件」代表腦部本身，「軟件」代表腦部中的思想。而你現在講，「韌體」是「軟件」的其中一種。那樣，你想用「韌體」這個概念，來比喻哪一類思想呢？）
「作業系統」代表「思考習慣」和「生活模式」。你試想一想，有什麼思想，比「思考習慣」和「生活模式」更加頑固？
那一類思想，就可以比喻成「韌體」。
如果「作業系統」代表「思考模式」，「韌體」大概可以指「思考傾向」。「思考傾向」可以說是來自於「潛意識」。但是，「潛意識」這個用語在這裡，未必有大意義，因為，我只是把自己腦中思想的未知部分，統稱為「潛意識」罷了。到頭來，「潛意識」是什麼，或者「潛意識」從何以來，仍然是一個未知之數，仍然需要另外的考究。
（安：我又不覺得，那完全是一個未知項。你已經把「潛意識」，解釋成「思考傾向的來源」。那就不算是完全未知。還有，既然你已經把「潛意識」比喻成「韌體」，何不從這個方向追究，「潛意識」如何形成？）
— Me@2012.04.20
2012.04.20 Friday (c) All rights reserved by ACHK
People get a lot of confusion, because they keep trying to think of quantum mechanics as classical mechanics.
— Quantum Mechanics in Your Face
— Sidney Coleman
— Apr. 9, 1994
2012.04.19 Thursday ACHK
.
Be consistent, not uniform
— Government Digital Service Design Principles
2012.04.19 Thursday ACHK
這段改編自 2010 年 6 月 2 日的對話。
你這道機會率題目做錯了。我建議你不要自己追究，自己的想法錯在哪裡，因為，有時一些錯誤的想法，很難可以自己指出錯在何處，除非你的造詣，已經達到大師的級數。
例如，你試一試指出，以下的論證，有何不妥之處：
擁有一支筆 好過 沒有任何東西；
沒有任何東西 好過 擁有一位好太太。
結論：
擁有一支筆 好過 擁有一位好太太。
如果想追究想法錯在哪裡，你可以直接問我。我的機會率精神狀態，間中會達到大師的境界。
— Me@2012.04.19
2012.04.19 Thursday (c) All rights reserved by ACHK
Universal wave function, 17.2
Relativity
Pilot wave theory is explicitly nonlocal. As a consequence, most relativistic variants of pilot wave theory need a foliation of space-time. While this is in conflict with the standard interpretation of relativity, the preferred foliation, if unobservable, does not lead to any empirical conflicts with relativity.
The relation between nonlocality and preferred foliation can be better understood as follows. In de Broglie–Bohm theory, nonlocality manifests as the fact that the velocity and acceleration of one particle depends on the instantaneous positions of all other particles. On the other hand, in the theory of relativity the concept of instantaneousness does not have an invariant meaning. Thus, to define particle trajectories, one needs an additional rule that defines which space-time points should be considered instantaneous. The simplest way to achieve this is to introduce a preferred foliation of space-time by hand, such that each hypersurface of the foliation defines a hypersurface of equal time.
However, this way (which explicitly breaks the relativistic covariance) is not the only way. It is also possible that a rule which defines instantaneousness is contingent, by emerging dynamically from relativistic covariant laws combined with particular initial conditions. In this way, the need for a preferred foliation can be avoided and relativistic covariance can be saved.
…
There has been work in developing relativistic versions of de Broglie–Bohm theory.
— Wikipedia on De Broglie–Bohm theory
2012.04.18 Wednesday ACHK
Never forget what someone says to you when they’re angry, because that’s when the cover-up truth comes out.
—
2012.04.18 Wednesday ACHK
軟硬智力 5.4
這段改編自 2010 年 3 月 20 日的對話。
在電腦中，「firmware」（韌體／固件）是軟件的一種。一般的軟件，無論是「應用程式」，還是「作業系統」，都是儲存在硬碟之內。但是，「韌體」卻是儲存於，個別硬件（hardware）自己的晶片之內，負責該個硬件本身的運作。例如，主機板（motherboard）的韌體，是晶片內的程式，負責主機板和其他硬體（hardware）的銜接和溝通。
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| This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. Author: Appaloosa |
又例如，顯示卡晶片內的程式，負責顯示卡本身和其他硬體（主要是中央處理器與顯示屏）的訊息往來。
因為韌體不是儲存於硬碟（hard disk drive）內，更改韌體，比起更改「作業系統」，還要困難得多。你說要「更改韌體」，和你說要「更換硬件」，意思其實差不多，因為「更改韌體」的最快捷方法是，直情把該個硬件換掉。例如，如果你電腦的顯示卡表現不佳，你會聯想到，可能需要安裝一張較強的顯示卡。但是，你大概不會考慮，不如先升級顯示卡內的程式（韌體），看看能否提升效能。
（安：根據你剛才的比喻，「硬件」代表腦部本身，「軟件」代表腦部中的思想。而你現在講，「韌體」是「軟件」的其中一種。那樣，你想用「韌體」這個概念，來比喻哪一類思想呢？）
— Me@2012.04.18
2012.04.18 Wednesday (c) All rights reserved by ACHK
General relativity is consistent with the local conservation of energy and momentum …
— Wikipedia on Einstein field equations
2012.04.17 Tuesday ACHK
… Nobel laureate Sheldon Glashow told the Boston Globe. “… within the community of theoretical physicists, he’s kind of a major god. He is the physicist’s physicist.”
Coleman’s lectures at Harvard were also legendary. Students in one quantum field theory course created T-shirts bearing his image and a collection of his most noted quotations, among them: “Not only God knows, I know, and by the end of the semester, you will know.” Despite this acclaim, he did not generally enjoy teaching or mentoring graduate students:
I hate [teaching]. You do it as part of the job. Well, that’s of course false … or maybe more true than false when I say I hate it. … But I certainly would be just as happy if I had no graduate students. … Occasionally there is a graduate student who is a joy to collaborate with. Both David Politzer and Erick Weinberg were of this kind, but they were essentially almost mature physicists. They were very bright by the time they came to me. In general, working with a graduate student is like teaching a course. It’s tedious, unpleasant work. A pain in the neck. You do it because you’re paid to do it. If I weren’t paid to do it I certainly would never do it.
— Wikipedia on Sidney Coleman
2012.04.17 Tuesday ACHK
這段改編自 2010 年 6 月 2 日的對話。
機會率是一個分數。分子代表期望的結果；分母代表已知的東西，又名「樣本空間」。
即使期望的事件相同，如果已知的東西不同，都會導致機會率的數值有分別。例如，假設有一粒骰子是公平的，即是各個結果出現的機會率均等。如果要擲到「3」，機會率是多少呢？
期望的結果只有一個，就是擲到「3」，所以機會率分子是 1。樣本空間，就是所有可能結果的集合，即是｛1, 2, 3, 4, 5, 6｝。樣本空間，顯示總共有 6 個可能的結果，所以機會率分母是 6。答案是，擲到「3」的機會率是 1/6。
但是，如果你已知結果一定是單數，樣本空間就會收窄成｛1, 3, 5｝。因為現在只有 3 個可能的結果，機會率分母應該改為 3。結論是，擲到「3」的機會率是 1/3。
你現在用「集合論」中的「文氏圖」（Venn diagram），來分析一題機會率題目，理論上是合理的。但是，實際上，你要十分小心，因為「文氏圖」所直接表達的，只有期望的結果，即是「機會率分子」。稍一不留神，你會忘記了，還要考慮「樣本空間」，即是「機會率分母」。
— Me@2012.04.17
2012.04.17 Tuesday (c) All rights reserved by ACHK
Universal wave function, 17.1
The non-local hidden variables predict a genuine violation of the Lorentz symmetry. I think that all these theories predict such a brutal violation of the Lorentz symmetry that they are safely ruled out, too.
— Lubos Motl
The de Broglie–Bohm theory is explicitly non-local: The velocity of any one particle depends on the value of the wavefunction, which depends on the whole configuration of the universe. Because the known laws of physics are all local, and because non-local interactions combined with relativity lead to causal paradoxes, many physicists find this unacceptable.
This theory is deterministic. Most (but not all) variants of this theory that support special relativity require a preferred frame.
— Wikipedia on De Broglie–Bohm theory
2012.04.16 Monday ACHK
真相客觀程式 2
We want to stand upon our own feet and look fair and square at the world – its good facts, its bad facts, its beauties, and its ugliness; see the world as it is, and be not afraid of it. Conquer the world by intelligence, and not merely by being slavishly subdued by the terror that comes from it.
– Bertrand Russell
2012.04.16 Monday ACHK
軟硬智力 5.3
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| By Miko3k, Tene, Fri13 [GFDL or CC-BY-SA-3.0], via Wikimedia Commons |
2012.04.16 Monday ACHK
Physics Town 
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