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New QG blog-Yidun Wan

  1. May 8, 2006 #1

    marcus

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    New QG blog---Yidun Wan

    Back in October 2005 when Smolin gave his talk at Loops '05 conference he referred several times to work by a Perimeter/Waterloo PhD student called Yidun Wan (in the online audio he pronounces Yidun's name like Eton the school in UK where they play Rugby)

    I just learned that Yidun has a blog. I like the header photo, and how it is set up, and also the name. The blog is bilingual: quite a lot perhaps the majority is in Chinese. There are quite a few QG papers coming out of China these days---especially Beijing University but also other places---so it seems like a good idea to have a QG blog in Chinese. It also has entries in English.

    http://www.wanyidun.com/blog_r2u/?p=50

    Yidun has a background which is (to me) very interesting because he did a Masters at University of Pennsylvania in Computer Science, his webpage says, before entering the PhD program at Waterloo.
    I am always expecting QG physicists to construct computer models simulating spacetime-matter. Or to make computer models simulating some interesting graph-theoretical aspect, such as the (de)evolution of non-locality by purely local moves.

    Dan Christensen at UWO is a QG researcher with access to supercomputers and a program combining mathematics, physics, and computer science. IIRC one or more of Ashtekar's students at Penn State have gone to UWO to work with Dan Christensen. They have done some massive spinfoam calculations at UWO. I think there should be more programs like Christensen's at UWO that combine the necessary skills and computer-power.

    It seems like it would help if the QG field could attract some PhD students with a Computer Science background---especially background in simulations by massive parallel computation, or Monte Carlo methods. The salary gradient probably goes the wrong way. If you have a degree in Computer Science then you can make too much money (if you are good) so why go into theoretical physics?

    this bad salary gradient is probably the only reason that we do not see today huge computer models of spacetime-matter running at all major universities :smile: just kidding
     
    Last edited: May 8, 2006
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  3. May 8, 2006 #2

    marcus

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    Yidun blog on knots

    the blog (abbreviated r2u for "road to unification") has a way of getting the entries that are in English
    http://www.wanyidun.com/blog_r2u/?cat=8

    and when you scan down this you see some beautiful pictures of knots and some history of humans studying knots.

    did you know that the study of knot theory was begun by Gauss?

    ===quote r2u===
    ...It was Gauss (why always Gauss?) who initialized the study of knots and links. He created some basic calculus used to distinguish some knots and links from one another. More amazingly, he found a relation between the linking number of links and the electrogmagetism (we will come back to this point later). He considered knot theory as analysis situs and even predicted that it will become a main branch of future mathematics but not of the mathematics of his time...
    ===endquote===

    there are some photographs of traditional Chinese folk art knots. Tieing certain complicated knots, which have names and distinctive appearance, is a folk art form. also there are some pictures of more usual knots and an introduction to knot theory

    ===================

    this short essay on knots is especially a propos because in one kind of QG unification
    matter arises as knots in graph of space relationships.
     
    Last edited: May 8, 2006
  4. May 24, 2006 #3

    lqg

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    Thanks!

    Wow, what a nice free advertisement for my blog! Thanks a lot to you, Marcus! It is a great work for you to manage such a nice forum.

    Actually, I noticed on May 8th there was a burst of visitings on my blog, that must be due to this thread of you.:rofl:

    I would like to say a bit more about the languages in my posts. All posts regarding physics and math are in English or at least bilingual. For some essay-like posts requiring exquisite language skills, I prefer to use Chinese, because, as you may already noticed, my English is not good enough to handle them. However, I also have a problem with my Chinese in scientific writing that I do not know exact words of many physics/math terms in Chinese, since I did not do an advanced study of physics in China. I hope one day I will be able to write all the posts in both languages.

    Computer science is not a science, because we call it science. For a true science, we don't call it science, e.g. physics.:wink: By the way, it is a long story why I took so long to start doing physics.

    Eaton
     
  5. May 24, 2006 #4

    marcus

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    Heh heh. I dont manage. I provide some content. People like selfAdjoint and ZapperZ manage (and provide content as well).
    It is nice though. a really nice place.

    I see that the way to write your name---Wan---looks like PLANCK'S h-bar CONSTANT
    that seems cool, to spell your name with the h-bar symbol.

    I am just guessing from the small writing at upper left corner of your blog, which looks like it might be your name written in characters.

    I was amused by what you said about driving 1900 kilometers in 19 hours with a friend----and a total trip of 7000 kilometers during about a week break. I did some of that when I was much younger. it is probably crazy but it can feel good at the time, or used to. Now it would probably leave me a total wreck.

    the most interesting thing about your blog lately is that you are trying to explain GROUP FIELD THEORY. that is something i try to understand from time to time and always find a bit difficult, so i am glad you are tackling it in your blog.

    ciao,
    thanks for coming to visit us as "lqg"
     
    Last edited: May 24, 2006
  6. May 25, 2006 #5

    lqg

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    Then thank everyone who contributed to this great forum! You have written a lot!
    I actually come often, but just don't say anything, because I guess it is better for me to listen than to speak on my current level.:tongue2:

    You guessed the right Chinese character for my last name. It looks like h-bar. However, there is another Chinese character, which is closer to the shape of h-bar.

    I am just learning GFT. I would like to share what I learned with others who are interested and expect their criticism.

    Btw, the center of LQG in China is not in Being University but in Being Normal University and Nanchang University. It is truely a center because of its tiny size.:wink:
     
  7. May 25, 2006 #6

    marcus

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    visiting your blog got me interested in Pinyin and characters. I found a useful dictionary called CEDICT
    http://www.mandarintools.com/worddict.html

    please say what is the Pinyin for "Beijing Normal"

    on my exercise walk up the hill, I happened to meet a retired physicist from China (also getting exercise) and I asked him how do you say "Bejing Normal". He said there are two universities in Beijing one called
    BEI DA and the other called CHIN HUA (I am just guessing phonetically about spelling)
    and he did not know which one should be translated "Beijing Normal".

    this puzzled me because I know that there were 4 or 5 people from Beijing Normal at the Loops '05 coference at Potsdam last year. So how can this gentleman who was educated in China not know of Beijing Normal?
     
    Last edited: May 25, 2006
  8. May 25, 2006 #7
    Please start a thread. You can call it "GFT".
    One question I have about GFT is whether there is not a corresponding Algebraic Quantum Field Theory. I guess that there might be since for a Lie group there is a corresponding algebra. Does this Group/Algebra correspondence occur in Group Field Theories as well? Thanks.
     
    Last edited: May 25, 2006
  9. May 25, 2006 #8

    marcus

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    Eaton already did start a discussion of it at his blog
    (so I would not expect him to start a parallel one here because it would duplicate effort---he must have to budget his time since in PhD program)

    check out his blog, you will see he is just getting started talking about GFT.
    hard topic, in my opinion
    ===================

    btw I used that CEDICT to interpret some characters that I saw at YiDun's blog. they show tones by accent marks, like YI4 is yi in the firm falling fourth tone, spelled yì (you see the accent is sloping down, like the fourth tone when spoken)
    and the meaning of the character is basically "correctness"
    (you can say justice or righteousness in other contexts)
    and DUN is written dùn, by coincidence it also happens to be fourth tone. And the dictionary meaning appears to be something like a MEASURE IN MUSIC (a beat, a pause, a timeperiod, a workbreak). It doesnt appear to have one unambiguous meaning).

    So I think you could PHILOSOPHICALLY INTERPRET the name YiDun as having a connotation of "correct timing" or "correct measure"

    Admittedly this would be an inappropriate way to treat a NAME because a name is just a name, like William, or Smith.

    this dictionary CEDICT is quite fun to use, if you have any curiosity about Chinese characters.

    ============
    [edit] I just looked up the word-meaning of the surname Wan and as a word it means ten thousand, or more generally "a large number"-----and the symbol for it looks a little bit like h-bar

    Eaton probably thinks it is funny for people to look at his blog and begin trying to figure out chinese writing, but that is what he gets for putting up a nice-looking bilingual blog
     
    Last edited: May 25, 2006
  10. May 25, 2006 #9

    lqg

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    The Pinyin for "Beijing Normal" is "Beijing Shifan".
    I don't know that person. But there is only one "Bei Da" in Beijing, which is the short for Beijing University or Peking University. The other is "Qing Hua" rather than "Chin Hua". Yah, I don't know how this gentleman does not know Beijing Normal either.
     
  11. May 25, 2006 #10

    lqg

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    It is interesting to interpret my name in such a way. I wish I would be a "correct measure" in physics:tongue: There are more meaning of the characters of my name. However, I don't care the meaning so much. The true story of my name is complicated. I am not sure if I would be able to make this clear, but I'll try as follows.
    Last name is simple. Yidun should be understood separately somehow. The character "Yi" in my name was actually determined about 300 years ago for me and for anyone at the same level as I am at in the hierarchy of this Wan's family. Usually, a kind of prebytery of the family writes down a Chinese poem of certain number of sentences, each of which has the same number of characters. From then on, character in the poem will be used in the order as they are in the poem for the pre-fixed name for the descendents. That is, each character corresponds to a generation. The poem as a whole has an auspicious meaning. After several hundred years when the poem is used up, a new prebytery at that time will need to figure out a new poem with different characters to continue this "game".
    In my case, the current poem has 8 sentences, each of which has 5 characters. There are thus 40 characters which can be used for 40 generations. Mine, "Yi" is the very 12th in this poem. In my hometown, there are people (of course with Wan as their last name) who are named with the 17th character in this poem. That's why I said "Yi" was determined to be my name about 300 years ago. So, only "dun" was given by my parents for me.
    Interestingly, if you met someone in the future who's name is also "Wan Yi" plus something, he may be a cousine of mine.:tongue:
    This is only a small part of the whole story of Chinese traditional naming system. As a side effect of modernization, much of our tradition has been forgotten or discarded by our people. However, we still keep a large portion of the tradition in my family.

    If you did not see what I said above, please just forget it. I will tell you later again when I can explain traditional Chinese stuff in English in a better way.
     
  12. May 25, 2006 #11

    marcus

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    This was over a month ago that I asked him and I think now he DID say Qing Hua, I merely remembered that wrong. He may not have understood my question. I did not hear him say "Beijing Shifan". I heard him say there are TWO important universities in Beijing---and when he was a student at Bei Da they would have regular fights with the students of Qing Hua.

    We were discussing some of the excessive behavior of UC Berkeley students and Stanford students.

    Anyway, thank you. Now finally I know it is Beijing Shifan where all the quantum gravity people seem to come from. It is not important for me to know this. I only suffer from idle curiosity.
     
  13. May 25, 2006 #12

    marcus

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    excuse me for being so curious into personal matters, but does the poem rhyme?

    I happen to like poems that rhyme and I have been told that many classical chinese poems do this. (as do, of course, many older European poems also).

    I mean specifically END rhyme where the syllable at the end of the line rhymes with the syllable at the end of the next, or some other, line.

    If you have a son or daughter that person will receive the syllable number 13 of the poem. How do you like that syllable? Have you thought about it?

    Personally I find this system of names beautiful and interesting because, as the people of this town or region continue to have children generation after generation they are spelling out the poem through many years.

    (I see a problem with daughters here, if the name Wan goes with the sons----daughters would not continue the system as perfectly)

    I never heard of anything like this. Thank you for telling us about it!

    =============
    the word presbyter originally meant someone who is OLDER (another way to say it is an ELDER)
    and we get the word "priest" from the word presbyter----by saying it quickly and gradually forgetting to pronounce all the sounds.

    the early christians did not always have official priests but the community would have a GROUP of older people called "the Council of Elders". This group was also called the "presbytery" but now that word is nearly forgotten.

    everything you wrote about this is perfect and clear except that you should probably call the person who composed the poem an Elder. If he wears a special garb (like a costume or uniform) he is a Priest. If he does not have special clothes but just looks normal (but is especially respected by the people) then he is an Elder.

    this is incredibly fascinating! I will force myself to stop because I don't want to irritate Lee Smolin. He probabably has graduate student work for you to do and wants to keep you busy, so we will make him crazy if we talk all the time about chinese and european customs!
     
    Last edited: May 25, 2006
  14. May 25, 2006 #13

    lqg

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    Fine. This is not a secret though.
    The poem certainly rhymes, since otherwise it is not a Chinese poem. However, that two characters rhyme each other does not necessary mean that they sounds very similar.
    My son is 1 year and 9 months now. He takes the very 13th character for his name and my father gave him the third character for his name.
    Yes, you'r right. Daughters are not named with the characters in the poem. Peole invented funny ways to get around the problem if the there are only daughters in the new generation.:confused:
    Allow me tell you more. The word "name" in chinese is "Ming zi", "Ming" and "Zi" are different. However this correspondence is not so true. In the past, one is not allowed to have his "Zi" before his 20th birthday. That is, one can only have a "Ming", which precisely corresponds to "name", before he is 20 years old. 20th birthday is very important in a man's life. A special ceremony, called "Guan Li" is usually held on that day. "Guan" means a hat as a noun and means "put a hat on one's head" as a verb. In this contex, it is a verb. In such a ceremony of a young man, the elder in the family puts a hat on his head. After this event, he is admitted by people as an adult. I only have a "Ming", which is right "Yi dun". But my father already proposed a "Zi" for my son that is not gonna be used for now.
     
    Last edited: May 25, 2006
  15. May 25, 2006 #14

    lqg

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    Marcus,
    Thanks for pointing out my inappropriate use of that word. I used "elder" in the previous reply. The reason why I used presbytery is that those elders in the family have great power in making decisions and judgements.
     
  16. May 25, 2006 #15

    marcus

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    I am very happy to know all these interesting things.
    Work hard on your physics. We will talk later.
     
  17. May 25, 2006 #16

    lqg

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    Hah, hah. Thanks! He only talks to me about physics. :wink: No worry, this is during my dinner break.:wink: But sure, we can stop now.
     
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