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Tsung-Dao Lee, physicist who challenged a law of nature, has died

nytimes.com

11–20 of 81 posts

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#12
Feynman wrote a exceptionally clear explanation of this experiment and what it meant:

- "To illustrate the whole problem still more clearly, imagine that we were talking to a Martian, or someone very far away, by telephone. We are not allowed to send him any actual samples to inspect; for instance, if we could send light, we could send him right-hand circularly polarized light and say, “That is right-hand light—just watch the way it is going.” But we cannot give him anything, we can only talk to him. He is far away, or in some strange location, and he cannot see anything we can see. For instance, we cannot say, “Look at Ursa major; now see how those stars are arranged. What we mean by ‘right’ is …” We are only allowed to telephone him."

- "Now we want to tell him all about us. Of course, first we start defining numbers, and say, “Tick, tick, two, tick, tick, tick, three, …,” so that gradually he can understand a couple of words, and so on. After a while we may become very familiar with this fellow, and he says, “What do you guys look like?” We start to describe ourselves, and say, “Well, we are six feet tall.” He says, “Wait a minute, what is six feet?” Is it possible to tell him what six feet is? Certainly! We say, “You know about the diameter of hydrogen atoms—we are 17,000,000,000 hydrogen atoms high!” That is possible because physical laws are not invariant under change of scale, and therefore we can define an absolute length. And so we define the size of the body, and tell him what the general shape is—it has prongs with five bumps sticking out on the ends, and so on, and he follows us along, and we finish describing how we look on the outside, presumably without encountering any particular difficulties. He is even making a model of us as we go along. He says, “My, you are certainly very handsome fellows; now what is on the inside?” So we start to describe the various organs on the inside, and we come to the heart, and we carefully describe the shape of it, and say, “Now put the heart on the left side.” He says, “Duhhh—the left side?” Now our problem is to describe to him which side the heart goes on without his ever seeing anything that we see, and without our ever sending any sample to him of what we mean by “right”—no standard right-handed object. Can we do it?"

https://www.feynmanlectures.caltech.edu/I_52.html

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#13

Feynman wrote a exceptionally clear explanation of this experiment and what it meant: - "To illustrate the whole problem still more clearly, imagine that we were talking to a Martian, or someone very far away, by telephone. We are not allowed to send him any actual samples to inspect; for instance, if we could send light, we could send him right-hand circularly polarized light and say, “That is right-hand light—just…

“Try to teach an alien on a telephone about left and right” actually sounds like a fun game to try with a class full of kids.

I would solve this particular circumstance by using the andromeda galaxy (“the closest galaxy”) as a reference, but it definitely stumped me for a bit.

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#14
Is it just me or does anyone also get this odd feeling when people use phrases like "challenged a law of nature". Makes it sound like he did something that is physically impossible when he actually attempted something that was believed to be impossible or highly unlikely

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#15
post #10

This headline would suggest Tsung-Dao Lee challenged the law of gravity by jumping from a building and failing to make his point.

And the lesson is.. never challenge a law of nature.

Also, this comes to mind: https://www.youtube.com/watch?v=AL8chWFuM-s

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#16

Is it just me or does anyone also get this odd feeling when people use phrases like "challenged a law of nature". Makes it sound like he did something that is physically impossible when he actually attempted something that was believed to be impossible or highly unlikely

Yes, it's not only you, it'll less confusing and more accurate statement should be who challenged the understanding of natural laws but then the headline would not be sensational. Anything that challenged law of nature can be considered miracles for biblical examples the creation of Adam and Eve without parents, and Jesus virgin birth.

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#17

Feynman wrote a exceptionally clear explanation of this experiment and what it meant: - "To illustrate the whole problem still more clearly, imagine that we were talking to a Martian, or someone very far away, by telephone. We are not allowed to send him any actual samples to inspect; for instance, if we could send light, we could send him right-hand circularly polarized light and say, “That is right-hand light—just…

“Try to teach an alien on a telephone about left and right” actually sounds like a fun game to try with a class full of kids. I would solve this particular circumstance by using the andromeda galaxy (“the closest galaxy”) as a reference, but it definitely stumped me for a bit.

You can't use cancellation or heavenly bodies:

"He is far away, or in some strange location, and he cannot see anything we can see. For instance, we cannot say, “Look at Ursa major; now see how those stars are arranged. What we mean by ‘right’ is …” We are only allowed to telephone him."

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#19

Earlier quoted context omitted.

“Try to teach an alien on a telephone about left and right” actually sounds like a fun game to try with a class full of kids. I would solve this particular circumstance by using the andromeda galaxy (“the closest galaxy”) as a reference, but it definitely stumped me for a bit.

You can't use cancellation or heavenly bodies: "He is far away, or in some strange location, and he cannot see anything we can see. For instance, we cannot say, “Look at Ursa major; now see how those stars are arranged. What we mean by ‘right’ is …” We are only allowed to telephone him."

Ah good catch, I somehow still assumed same galaxy.

Thinking about it, ironically I think the direct mention of Ursa Major might have played a part in that.

Re: Tsung-Dao Lee, physicist who challenged a law of nature, has died

#20
> Lee became Dr. Fermi’s sole doctoral student in theoretical physics, meeting with him every week. It was an extraordinary learning experience, partly because of Dr. Fermi’s teaching technique, which Dr. Lee explained in the 2007 interview with the Nobel Institute. “‘You see,’ he said, ‘there are things that I would like to know,’” Dr. Lee recalled Dr. Fermi saying. “‘Lee, why don’t you look up and give me a lecture next week.’” “I was very happy to teach Fermi,” Dr. Lee added. “Of course, this is an excellent way of building the student’s confidence. And then he would ask me questions and I would have to answer.”

Was fascinated by this. His advisor, Fermi, made Lee teach him stuff, not the other way around!

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