# BBC Brain Story, 3

I recommend the following BBC documentaries:

1. Brain Story

2. The Human Mind

3. The Human Body

4. The Human Face

5. Human Instinct

6. Human Senses

— Me@2013-01-31 10:14:26 AM

# Regret

Another sort of false prayers are our regrets. Discontent is the want of self-reliance: it is infirmity of will. Regret calamities, if you can thereby help the sufferer; if not, attend your own work, and already the evil begins to be repaired.

— Emerson

.

.

2008.03.11 Tuesday CHK2

# 乘法意思 1.1

Young man, in mathematics you don’t understand things. You just get used to them.

— John von Neumann

（安：「3 乘以 2」即是有兩個 3 加在一起，所以是 6。

3 x 2 = 3 + 3 = 6

3 x 2.1 = ?

（安：我們可以把「3 乘以 2.1」，看成有三個 2.1 加在一起：

3 x 2.1

= 2.1 x 3

= 2.1 + 2.1 + 2.1

= 6.3

— Me@2013.01.30

# No-cloning theorem 3

No-cloning in a classical context

There is a classical analogue to the quantum no-cloning theorem, which we might state as follows: given only the result of one flip of a (possibly biased) coin, we cannot simulate a second, independent toss of the same coin. The proof of this statement uses the linearity of classical probability, and has exactly the same structure as the proof of the quantum no-cloning theorem.

Thus if we wish to claim that no-cloning is a uniquely quantum result, some care is necessary in stating the theorem. One way of restricting the result to quantum mechanics is to restrict the states to pure states, where a pure state is defined to be one that is not a convex combination of other states. The classical pure states are pairwise orthogonal, but quantum pure states are not.

— Wikipedia on No-cloning theorem

2013.01.30 Wednesday ACHK

# Power

power ~ number of choices

— Me@2013.01.28

# 驗算極限 1.1

lim_{x -> 3} (x^2 – 9)/(x – 3) = 6

(3.001^2 – 9)/(3.001 – 3) = 6.001

lim_{x -> infinity} (3 x^2 – 9 x – 3)(4 x^2 – 3)

(3 (100000)^2 – 9 (100000) – 3}{4(100000)^2 – 3)

(3 (100000)^2 – 9 (100000) – 3)/(4(100000)^2 – 3) = 0.7499775

— Me@2013.01.29

# Phantoms in the Brain

Phantoms in the Brain: Probing the Mysteries of the Human Mind
by V. S. Ramachandran, Sandra Blakeslee

2013.01.28 Monday ACHK

# Answer to the Ultimate Question of Life, the Universe, and Everything

Cosmic religion 2

Whatever the nature of life and universe is, doing good is good.

— Me@2010.12.12

But be careful. By “doing good”, I refer to long-term good. Sometimes, short-term goods would create long-term evils. You should avoid doing such kind of goods.

Also, even for long-term goods, you should consider the opportunity costs. As your time is limited, you cannot do them all. You have to prioritize.

— Me@2013-01-28 11:33:24 AM

# 平行宇宙 3.3

The difference that makes no difference makes no difference.

— Me@2013.01.28

# Schrodinger’s cat

You should not apply a single-particle wavefunction to Schrodinger’s cat. Instead, you should either use classical physics or use a wavefunction for all the particles of the cat.

— Me@2013-01-23 10:25:00 AM

The uncertainty in Schrodinger’s cat’s life or death problem is classical uncertainty, not quantum uncertainty. For an observer outside the box, the cat is in a mixed state, not just a superposition of quantum eigenstates. The probability in a mixed state is classical, not quantum.

— Me@2013-01-27 09:59:13 AM

# 大世界 6.2

Self Reliance 7

.

.

I am only a small part of this world.

But this small part is already my whole world.

— Me@2013-01-26 02:15:26 PM

.

.

2008.01.26 Saturday $CHK_2$

# 考慮次序與否 2.2

P 方法：

S 方法：

（＿）
（   ）

（＿＿＿＿）
（10_C_3）

（3_C_2）（3_C_1）（4_C_0）
＿＿＿＿＿＿＿＿＿＿＿＿
（10_C_3）

（3）（3）（1）
= ＿＿＿＿＿
（120）

（3）（3）（1）
＿＿＿＿＿
（120）

= 3/40

— Me@2013.01.27

— Me@2012.10.17

# Energy conservation, 4

Is Energy Conserved in General Relativity?

In special cases, yes. In general — it depends on what you mean by “energy”, and what you mean by “conserved”.

We will not delve into definitions of energy in general relativity such as the hamiltonian (amusingly, the energy of a closed universe always works out to zero according to this definition), various kinds of energy one hopes to obtain by “deparametrizing” Einstein’s equations, or “quasilocal energy”.  There’s quite a bit to say about this sort of thing!  Indeed, the issue of energy in general relativity has a lot to do with the notorious “problem of time” in quantum gravity. . . but that’s another can of worms.

— Original by Michael Weiss and John Baez

2013.01.26 Saturday ACHK

# 大世界 6

R4

Idiot 3

.

.

– Ludwig Wittgenstein

.

– Translation, Me@2009.09.16

.

.

.

.

.

.

.

.

.

.

.

.

– Me@2009.09.17

.

.

.

2009.09.18 Friday (c) ACHK

# 平行宇宙 3.2

（安：但是，我問題的前提是，我有一部時光機。我有可能由一個平行宇宙「甲」，走到另一個平行宇宙「乙」。那樣，「宇宙甲」就可以透過我和我的時光機，去影響「宇宙乙」。甲乙就開始有因果關係。原本的兩個「平行宇宙」，亦都不再「平行」。那樣，難道甲乙宇宙，就為之「二合為一」嗎？

The difference that makes no difference makes no difference.

— Me@2013.01.26

# web.py

The web.py slogan is: “Think about the ideal way to write a web app. Write the code to make it happen.”

This is literally how I developed web.py. I wrote a web application in Python just imagining how I wanted the API to be.

— The web.py Philosophy

— Aaron Swartz

2013.01.25 Friday ACHK

# Writing and Speaking

I’m not a very good speaker. I say “um” a lot. Sometimes I have to pause when I lose my train of thought. I wish I were a better speaker. But I don’t wish I were a better speaker like I wish I were a better writer. What I really want is to have good ideas, and that’s a much bigger part of being a good writer than being a good speaker.

Having good ideas is most of writing well. If you know what you’re talking about, you can say it in the plainest words and you’ll be perceived as having a good style. With speaking it’s the opposite: having good ideas is an alarmingly small component of being a good speaker.

I first noticed this at a conference several years ago. There was another speaker who was much better than me. He had all of us roaring with laughter. I seemed awkward and halting by comparison. Afterward I put my talk online like I usually do. As I was doing it I tried to imagine what a transcript of the other guy’s talk would be like, and it was only then I realized he hadn’t said very much.

— Writing and Speaking

— March 2012

— Paul Graham

2013.01.25 Friday ACHK

# 考慮次序與否 2.1

P 方法：

（＿）（＿）（＿）

（3/10）（＿）（＿）

（3/10）（2/9）（＿）

（3/10）（2/9）（3/8）

（3/10）（2/9）（3/8）

= 1/40

（A）（A）（B）

（A）（B）（A）

（B）（A）（A）

（HYC：這一題很明顯是只有三種情況。但是，當題目不是那麼簡單，數字不是那麼小，而是要我選（例如）「四 C 三 A」時，我怎樣保證，可以羅列所有相關的情況，沒有遺漏？）

（＿）（＿）（＿）

（3/10）（2/9）（3/8）3_C_1

=（1/40）3

= 3/40

（HYC：我明白為何共有 3_C_1 種情況。但是，我不明白，為何只要將 3_C_1 乘上其中一個案例的機會率，就可以得到整體的機會率。）

（A）（A）（B）=（＿）（＿）（＿）

（A）（B）（A）=（＿）（＿）（＿）

（B）（A）（A）=（＿）（＿）（＿）

（A）（A）（B）=（3/10）（2/9）（3/8）= 1/40

（A）（B）（A）=（＿）（＿）（＿）

（B）（A）（A）=（＿）（＿）（＿）

（A）（A）（B）=（3/10）（2/9）（3/8）= 1/40

（A）（B）（A）=（3/10）（3/9）（2/8）

（B）（A）（A）=（＿）（＿）（＿）

（A）（A）（B）=（3/10）（2/9）（3/8）= 1/40

（A）（B）（A）=（3/10）（3/9）（2/8）

（B）（A）（A）=（3/10）（3/9）（2/8）

（A）（A）（B）=（3/10）（2/9）（3/8）= 1/40

（A）（B）（A）=（3/10）（3/9）（2/8）= 1/40

（B）（A）（A）=（3/10）（3/9）（2/8）= 1/40

— Me@2013.01.24

— Me@2012.10.17

# Chrono Trigger

.
Setting Out! The Dreamy Millennial Festival
The Queen who Returned
The Vanished Princess
I’m Home!
Kingdom Trial
Across the Ruins……
Factory Ruins in the Land of Mystery
The Farthest Reaches of Time
People of the Demon Village
Appeared: The Legendary Hero
Tarta and Frog
Red Stone, Rare Stone
Footprints! Track!!
Fight! Grandleon
Decisive Battle! Magus Castle!!
Before You Realize It, Primeval
Law of the Earth
Kingdom of Magic: Zeal
Release the Seal, Call Forth a Storm
The Philosopher on Grief Mountain
That Which Awaits in the Sky
The Call of Lavos
The Ancient Era’s New King
The Egg of Time
To the Fateful Time……
At the End of the Planet’s Dream
.
– Chrono Compendium
.
.
.

2010.01.03 Sunday ACHK