[HN Gopher] Tsung-Dao Lee, physicist who challenged a law of nat...
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Tsung-Dao Lee, physicist who challenged a law of nature, has died
Author : nsoonhui
Score : 137 points
Date : 2024-08-06 11:49 UTC (1 days ago)
(HTM) web link (www.nytimes.com)
(TXT) w3m dump (www.nytimes.com)
| toomuchtodo wrote:
| https://en.wikipedia.org/wiki/Tsung-Dao_Lee
| Koshkin wrote:
| I wonder if the autograph in this copy of a T.D.'s book is real.
|
| https://www.amazon.com/Symmetries-Asymmetries-Particles-Jess...
| neonate wrote:
| https://archive.ph/7Gtuz
| toomuchtodo wrote:
| Related: https://news.ycombinator.com/item?id=41173850
| CHB0403085482 wrote:
| RIP Dr Lee....
| dredmorbius wrote:
| NPR Obit (from an earlier submission):
| <https://www.npr.org/2024/08/06/nx-s1-5065675/chinese-america...>
| Jun8 wrote:
| Chien-Shiung Wu, who conducted the experiment that proved Lee's
| (and Yang's) theory didn't share the Nobel Prize with them in
| 1956. When I read people lamenting the fact that Rosalind
| Franklin didn't get the Nobel due to sexism I wonder why Wu is
| not mentioned. For more information on the circumstances see
| https://physicsworld.com/a/overlooked-for-the-nobel-chien-sh...
| zem wrote:
| I believe a large part of it is that DNA is a famous discovery,
| and lots of people have heard of the double helix story. far
| fewer would know about Lee and Yang or understand the first
| thing about what they discovered.
| sampo wrote:
| > the fact that Rosalind Franklin didn't get the Nobel due to
| sexism
|
| The primary reason why Rosalind Franklin didn't get a Nobel is
| that she died in 1958. It's maybe not easy to speculate what
| would have happened in the alternate timeline where she had
| lived until the Nobel nominations started to happen.
| KingMob wrote:
| For those unaware: the Nobel is not awarded posthumously.
| dekhn wrote:
| The primary reason Franklin didn't get the Nobel is that she
| didn't contribute the key component of the discovery: that
| DNA is a _double_ helix that is _antiparallel_.
| ioblomov wrote:
| In his memoir of their discovery, _The Double Helix_ , James
| Watson suggests that, had Franklin not died due to cancer a
| few years after their ground-breaking research, she might
| have shared their Nobel. He further speculates that since her
| protege Aaron Klug later won the Nobel in chemistry for his
| X-ray crystallography work (techniques she introduced him
| to), it wouldn't be far-fetched to imagine her having been a
| double laureate.
| GemesAS wrote:
| I think part of it was there a number of subsequent experiments
| that would also confirmed Lee & Yang's prediction in short
| order.
|
| My PhD advisor worked with Wu at Columbia. He held her in very
| high esteem.
| thbb123 wrote:
| This headline would suggest Tsung-Dao Lee challenged the law of
| gravity by jumping from a building and failing to make his point.
| g15jv2dp wrote:
| I don't think anybody understood the headline like that.
| dwighttk wrote:
| That was my first thought... I thought it was silly, but it
| was my first thought.
| throw310822 wrote:
| And the lesson is.. never challenge a law of nature.
|
| Also, this comes to mind:
| https://www.youtube.com/watch?v=AL8chWFuM-s
| dessimus wrote:
| One might even say: He fought the law, and the law won.
| dghughes wrote:
| Yeah that headline is bonkers. As if there were a duel and Lee
| lost.
| perihelions wrote:
| 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
| Modified3019 wrote:
| "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.
| samanator wrote:
| 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."
| Modified3019 wrote:
| 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.
| noworld wrote:
| "imagine that we were talking to a Martian"
| indoordin0saur wrote:
| I think by Martian he just meant "alien". Obviously if
| you're on Mars you could use all sorts of celestial
| bodies to demonstrate chirality.
| lern_too_spel wrote:
| The rest of the story about developing a way to communicate
| with the alien is a significant part of Andy Weir's Project
| Hail Mary, which is also a good book for kids.
| AaronM wrote:
| I thought about this for a bit. One easy to use explanation for
| left and right is a number line. Smaller numbers are on the
| left and larger numbers are on the right. It's still an
| assumption that alien species would count that way.
| jodacola wrote:
| I think this still illustrates the problem, though: where is
| the start of the number line? Perhaps this alien species has
| a right-to-left written language. Or top to bottom. How would
| one help orient the alien to the left to right numbering
| system used in this language?
|
| Very interesting thought experiment while drinking my coffee
| this morning!
| DonaldFisk wrote:
| What if they draw a number line with smaller numbers on the
| right and larger numbers on the left?
| perihelions wrote:
| Indeed.
|
| There's nothing you possibly draw on paper that answers the
| question, in isolation. A diagram on paper means exactly
| the same thing if you simultaneously (i) flip it, and (ii)
| flip your mental interpretation if it.
|
| Or: if you run a software program on a raster image, there
| exists a different program that returns identical output
| given an input image which is mirror-flipped copy of the
| first one. (It's just the first program, plus a pre-
| processing step that flips its input (which is computable).
| If f is a computable program, and f(img) = "left" and
| f(flip(img)) = "right", there exists a computable program
| g=f[?]flip such that g(img) = "right" and g(flip(img)) =
| "left").
|
| Similarly: there's nothing you can do in complex analysis
| that can distinguish the case where all +sqrt(-1)'s are
| swapped with -sqrt(-1)'s. Nor can you invent _any math
| whatsoever_ that has an isomorphism to the plane, that
| works differently if the plane is mirror-reversed.
| meroes wrote:
| But we can distinguish i and -i by convention and keep
| consistent right? Akin to sending the distant alien a
| sample? It's in the abstract that we can't really tell
| them apart. But as soon as we are given any kind of
| starting point to form a convention, like the first
| mathematical textbook tells us which is i and which is
| -i, we have enough?
|
| I think of an unlabeled, unconnected graph of two
| vertices. If I just pick one and call it A say by
| pointing to it, that's enough. The trick is to do it for
| limited communication partners like the alien right?
| InitialLastName wrote:
| Is the number line even universal among humans? Do cultures
| that read top-to-bottom or right-to-left still conceptually
| sort the larger numbers to the right?
| dotancohen wrote:
| Why couldn't we just tell the aliens to observe the direction
| of the field lines of electromagnetism? We could define for
| them "lower potential energy direction" by describing gravity,
| then use that phrase for describing the motion of the electrons
| in a conducting wire around a magnetic coil.
| griffzhowl wrote:
| How would that allow you to distinguish the coil from its
| mirror image?
| jxy wrote:
| We chose a random direction as a convention, just as we chose
| a random charge as positive.
| dotancohen wrote:
| No, the electrons actually move in the same direction
| always, just as a free falling object always moves towards
| the locally dominant mass. We could call the direction of
| electron movement "right".
| snarkconjecture wrote:
| It's the magnetic field that has the arbitrary sign
| convention. You can't determine the direction of a
| magnetic field from observations without using the right
| hand rule.
| dotancohen wrote:
| You don't have to know the sign, you could tell which way
| the electrons are going.
|
| We tell the aliens: you take all sorts of organics with
| liquid inside (on earth we typically use a lemon, but
| other organics will do), and put a stake of element 29 in
| one side and a stake of element 30 in the other. You then
| connect them with a length of element 29. Keep trying
| different organics until you find one that works. They
| might not have lemons, but there is a good chance that
| something will eventually work.
|
| You'd need to predefine what the atomic numbers mean and
| some other things, but we're already assuming some level
| of communication already being established so this aspect
| is not far-fetched.
| pgalvin wrote:
| Okay, I've got elements 29 and 30. Which side do I put
| each on?
|
| See the problem? :)
| dotancohen wrote:
| No, it really doesn't matter. Have you never made a lemon
| or potato battery before?
| ko27 wrote:
| Congrats, you devised an experiment to determine left and
| right. The only issue? You need to know what's left and
| right when placing those elements.
| luxuryballs wrote:
| physicist L100, human anatomy L1 (the heart is in the center)
| blipvert wrote:
| Ha, I remember this from an old Open University TV lecture.
| They suggested looking at the spin of a particular particle. So
| eventually the alien arrives and it goes to shake
| hands/tentacles, but it's not holding out the right one as it
| has been taught is customary ...
|
| _BOOM_ annihilation
|
| Ah, the alien was made from antimatter, where the spin is
| different. Oops.
| netdevnet wrote:
| 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
| teleforce wrote:
| 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.
| pnut wrote:
| Well he ended up dying, so the lesson is clearly, be careful
| who you challenge.
| KwisatzHaderack wrote:
| > 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!
| lokimedes wrote:
| Pope without pontification!
| Koshkin wrote:
| Indeed, Fermi was called "the Pope of physics."
|
| _Fermi's "intuito fenomenale" -- phenomenal intuition -- and
| his near infallibility in predicting the results of
| experiments were characteristics that prompted colleagues at
| the University of Rome to designate him "the Pope."_
| busyant wrote:
| > Fermi, made Lee teach him stuff, not the other way around!
|
| In grad school, one of my profs said something to the effect
| of, "We expect you to aggressively eradicate any ignorance you
| have on the whatever papers we assign to you _before_ lecture.
| "
|
| Then we were Socratically interrogated _in_ lecture. For me, it
| was a great way to learn, even if I 'm not remotely in the
| class of Fermi and Lee.
| nyc111 wrote:
| "subatomic particles, contrary to what scientists thought, are
| always symmetrical."
|
| This cannot be called challenging a law of nature. He questions
| what his colleagues generally believed. He challenges a
| convention of physics profession not a law of nature. But we know
| that media must exaggerate to sell papers.
| davrosthedalek wrote:
| No. What he challenged was an assumed law of nature. All laws
| of nature are assumed, as you cannot prove them, or only proof
| them in the context of a theory (which you then have to
| assume). It was not a convention.
| nyc111 wrote:
| So, before Lee made his discovery physicists believed (or
| assumed, or conjectured, or theorized) that "the laws of
| physics were identical whether observed directly or as a
| mirror image." Lee and Yang proposed that this did not always
| hold. Their proposal was later confirmed by experiments.
|
| So, what physicists believed before Lee, was not a law of
| nature. Lee challenged what his colleagues believed to be
| true.
|
| But you are right all so called laws of physics are
| provisional.
| lutorm wrote:
| I met Lee briefly, along with a few other Nobel laureates, in
| 1991 at a weird symposium in Japan. Unlike some of the others, he
| was very friendly and relaxed. RIP.
| treetalker wrote:
| The photograph capturing the expression of Albert Camus among the
| other laureates is gold.
| greatNespresso wrote:
| Just clicked to see his face, confirmed it's was worth it
| nyc111 wrote:
| "for discovering that subatomic particles, [...] are always
| symmetrical."
|
| "for overturning what had been considered a fundamental law of
| nature -- that particles are always symmetrical"
|
| The first sentence from the subhead is wrong. The second sentence
| is correct. "the laws of physics are not identical when observed
| directly or as a mirror image."
| timetraveller26 wrote:
| Who wrote this headline? It may sound as if breaking a nature's
| law was the direct cause of his death.
| xiaodai wrote:
| The first Chinese national to win a Nobel Prize!
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