2007年8月25日星期六

商用 BT

BitTorrent (BT) 的分發技術似乎又有新發展。以前,BT 大概可以說是一種民用的技術。這技術是一個普通電腦程式師發明和發揚光大的。自此,就有不少的電腦使用者利用這種技術分發檔案。當中的檔案,我想大部份都是有版權的商品,包括音樂 MP3,電影(VCD,DVD 或已經壓縮的格式)和軟件等。

這種技術大大的加速了分發具版權的檔案,所以一時引起了各商品受益人的反感,想要壓制這種分發檔案的技術。其實,錯不在這種技術,而是那些將檔案於上 BT 網絡上的人。如果我們可以好好的利用這種技術,說不定會為商業世界帶來新契機。

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2007年8月13日星期一

IAS Distinguished Lecture Series: The Future of Physics

The speaker of the talk is Prof. David Gross, Nobel Laureate of Physics in 2004. Prof. Gross discuss about 25 questions that might guide Physics in the next 25 years. The questions range from cosmology to Biophysics.

  • How did the universe begin?
    • How far can we probe?
    • Can string theory determine initial conditions?
    • Was there a time before the big bang?
    • Is time itself an emergent concept?
    • How does time begin?
  • What is the nature of dark matters (~21%)?
    • How do we detect dark matter?
    • Can we produce them in the laboratory?
  • What is the nature of dark energy (~75%)?
    • Is it constant or varying in time?
    • Or is it just the Einstein's cosmological constant, Λ?
  • How do stars form?
    • How do we understand spectrum of masses, frequency of binaries and clusters?
  • How do planets form?
    • What is the frequency of habitable planets?
  • Is General Relativity valid in all scales?
    • Would it breakdown at small distance and/or strong field?
  • Is gravitational waves detectable?
  • Can we determine Kerr Metric of a blackhole experimentally?
  • Is quantum mechanics the ultimate description of nature or will it fail somewhere?
    • Fail at very short distances? (Resolved by string theory)
    • Fail in large complex systems? (the Schrodinger's cat)
    • Problems with conscious systems (problems of measurements)
  • Problems with Standard Model
    • Is there any pattern for the masses and interaction coefficients of the elementary particles?
  • Does quantum fluctuation give rise to an energy (= cosmology constant)?
    • Λobs ~ 10-4eV4 ≠ 0
    • Λtheory ~ 1060eV4
    • Why is there such a large inconsistency between the observed and theoretical values?
  • Are diamonds forever? (Is nucleus stable?) Why?
    • Proton's lifetime > 1032 years. Why is it so stable?
    • Can we significantly improve this measurement?
  • What is the origin of the enormous hierarchy of energy scales?
    • The scale (length, energy & time) of our living universe differs a lot from the natural scale (Planck scale)
  • Is there low energy supersymmetry?
    • Due to supersymmetry, there is a super-partner (super-particle) for each observed particle, e.g. quark → squark; electron
  • Can we solve quantum chromodynamics at long distance?
    • Possibly by dual string theory
  • What is string theory?
    • Actually string theory cannot be solved in approximative way. Yet now we cannot solve it in an exact manner.
  • What is space-time?
    • Is space-time an emergent concept?
  • Are there generic non-Fermi-liquid?
  • For quantum computers, how can we deal with the background noise?
    • In an quiet way - isolated from the noise
    • In an deaf way - "topological" quantum bits that are delocalized and that are totally decoupled from the noise
    • Can we construct an applicable quantum computer? (we need >10,000 QuBits)
  • Is there room temperature (or even higher temperature) superconductor?
  • Is there room temperature ferromagnet made by electronic (semiconductors) materials?
  • Theoretical Biology Problem
    • How to we think of analyze and exhibit dynamics over many wide-ranging time scales?
  • Genomics
    • Can theory of evolution be quantitative or predictive?
      For example, there may be a genomics question like this in the year of 2107:
      What is the outlook of the creature that have the DNA sequence of AAAGTCTGAC...... > Answer <
    • What is consciousness and/or memory?
    • Can one measure the onset of consciousness in infant? For instance, consciousness increases continuously with age? Or discontinuously?
  • Computational Physics
    • Will computer replace analytic techniques?
    • When will we have creative theoretical computers?
      • How do we train them? (With Jackson?)
  • In high energy Physics, will the experimental apparatus become unaffordable or too difficult to be built?
    • Can we find any alternative ways to prove/disprove the theories?
  • Will Physics be a useful subject in the next 25 years? (Yes, for sure)



Prof. Gross is specialized in high energy Physics, so inevitably the content of the talk had to have some bias towards those area, such as string theory and standard model etc.

In my view, most of the questions related to high energy Physics can't be resolved in a short time. Physicists still have to work really hard.

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2007年8月12日星期日

網絡時代

網絡時代--是一個給這個新世代的好名字吧?電腦和網絡的出現,使人類的生活有著巨大的轉變。現在的生活好像都離不開這兩個元素似的。網上聊天改變了以前使用電話的習慣;網誌使一種新的媒體平台誕生,令更多人可以參與和討論;愛聽音樂的不用再到 CD 店買了,只要在安坐家中上網買,然後下載就可。還有太多太多,YouTubeFaceBook 等等,全部都使網絡使用者比以前連繫得更緊,距離更短。

網絡時代有著另一個名稱,資訊爆炸的時代,兩者是等價的。

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2007年8月9日星期四

電腦雜誌

話說上一次買了本電腦雜誌,也在網上搜尋一下,更新自己的電腦知識。我發現電腦雜誌的存在價值愈來愈低。

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2007年8月1日星期三

逛高登

我想熟識電腦的人都應該知道黃金與高登這個地方。這座專門作為電腦電玩的商場,是很多電玩電腦發燒友其中一個必到之地(其餘的是旺角和灣仔的電腦商場)。也許很多人都知道其實黃金與高登其實是屬於不同的戶主的,而且他們並不相連。

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