Daily Archives: November 16, 2012

Single-world interpretation, 6.2.2

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Information lost, 5

In the Many-worlds interpretation (MWI), when we say that “a + b” collapses to “a”, there is a shift of definition of “you”.

MWI is in one sense correct: choice b version of you still exists. But the trick is that he is not in another universe. He is in the environment of this universe.

And perhaps in reverse, you are also part of the environment of him.

— Me@2011.11.20

This environment theory is not totally accurate. For example, in the photon double slit experiment, during the wave function collapse, 

sqrt(2) | left > + sqrt(2) | right >

–> | left >    ,

| right > as the unchosen choice, or the lost information, goes to the environment.      

However, the macroscopic reality of | photon goes left > requires not only the state of the photon but also the state of its environment, including the lost information | right >_micro. Just the lost information itself is not enough to form a macroscopic reality.

— Me@2012.04.03

2012.11.16 Friday (c) All rights reserved by ACHK

歸納筆記 2.2

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這段改編自 2010 年 6 月 8 日的對話。

試想想，如果你有在臨考前背誦「魔記筆記」，又怎可能在考試時「臨場遺忘」，內裡記載的常用技巧呢？

你們可能會問：「又怎可能在半小時內，把『魔法筆記』的所有內容，都閱讀一次呢？」

你留意，你現在手上的「魔法筆記」，並不是「真身」，而只是第一個版本。如果你跟足「魔法筆記方法」的劇情，臨考試前「魔法筆記」，一定會很薄。「魔法筆記」的原意，是把課程內容的（例如）四百頁，歸納成二百頁，成為第一個版本。然後，再把那二百頁，歸納成一百頁，成為第二版，如此類推。臨考試前的「魔法筆記」，應該只有少於五十頁。

另外，保證準時的唯一方法，就是大大提早到達。考試當日，正常人也會十分緊張，會提早出門，以防有突發交通事故。如果行程順利，你會在早於開考前的一個小時，就到達試場。所以，可用於背誦筆記的時間，通常也不只半小時那麼少。　

— Me@2012.11.16

2012.11.16 Friday (c) All rights reserved by ACHK

Philosophical Investigations

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Relation to the Tractatus

According to the standard reading, in the Philosophical Investigations Wittgenstein repudiates many of his own earlier views, expressed in the Tractatus Logico-Philosophicus. The Tractatus, as Bertrand Russell saw it (though it should be noted that Wittgenstein took strong exception to Russell’s reading), had been an attempt to set out a logically perfect language, building on Russell’s own work. In the years between the two works Wittgenstein came to reject the idea that underpinned logical atomism, that there were ultimate “simples” from which a language should, or even could, be constructed.

In remark #23 of Philosophical Investigations he points out that the practice of human language is more complex than the simplified views of language that have been held by those who seek to explain or simulate human language by means of a formal system. It would be a disastrous mistake, according to Wittgenstein, to see language as being in any way analogous to formal logic.

Instead, language has many context-sensitive expressions, such as indexicals.

— Wikipedia on Philosophical Investigations

2012.11.16 Friday ACHK