Daily Archives: January 4, 2011

Gluon

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Gluons (from English glue and the suffix -on) are elementary expressions of quark interaction, and are indirectly involved with the binding of protons and neutrons together in atomic nuclei through the strong force. The antiparticle of a gluon is another gluon (see Eight gluon colors below).

In technical terms, they are vector gauge bosons that mediate strong color charge interactions of quarks in quantum chromodynamics (QCD). Unlike the electrically neutral photon of quantum electrodynamics (QED), gluons themselves carry color charge and therefore participate in the strong interaction in addition to mediating it, making QCD significantly harder to analyze than QED.

— Wikipedia on Gluon

2011.01.04 Tuesday ACHK

Original

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* Next to the originator of a good sentence is the first quoter of it.

* A great man quotes bravely, and will not draw on his invention when his memory serves him with a word just as good.

* Genius borrows nobly. When Shakespeare is charged with debts to his authors, Landor replies: “Yet he was more original than his originals. He breathed upon dead bodies and brought them into life.”

— Ralph Waldo Emerson

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2011.01.04 Tuesday ACHK

驗算校對 1.1

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這段改篇自 2010 年 4 月 23 日的對話。

你加減乘除準不準確？

（CN：一題數式要左右對調時，就有時會錯。）

有兩種驗算策略：一種是，做完整份卷才開始驗算；另一種是，做完每題立刻驗算，驗算好才開始做下一題。我不知道，哪一種比較適合你。

（CN：我覺得應該做完整份卷才驗算，因為如果每題做完也立刻驗算的話，不會有足夠時間完成整份卷。）

「做完整份卷才驗算」的問題是，可能你整份卷根本完成不了，從而導致最後完全沒有任何驗算的機會。

（CN：但是，如果每題做完也立刻驗算的話，明明是原本有足夠時間完成的試卷，也會完成不了。）

可能真的是那樣。但是，「每題立刻驗算」會令到你凡是完成了的題目，都完全準確，即使你不能完成所有題目。

（CN：但是，後面那些你沒有時間完成的，可能正正是你擅長的題目。）

兩害取其輕。

（CN：那又是。）

每題立刻驗算的話，可能令你只能完成八成的題目，但是，那八成都是運算準確的。不每題立刻驗算的話，可能令你可以完成十成的題目，但是，那十成之中，有多少成是運算準確的，你也不敢估計。

其實，哪一個「害」比較大，要有上文下理：視乎是哪一個考生、哪一份試卷。所以，我並沒有說定，哪一個方法，比較適合你。

— Me@2011.01.04

2011.01.04 Tuesday (c) All rights reserved by ACHK