我第一次見到朱棣文是在1970年，當時他作為加州大學伯克利分校物理系一年級的研究生，加入了我的實驗室，選修了“熱力學”和“統(tǒng)計力學”的課題。時間不長，我就發(fā)現(xiàn)他非常的不一般：反應機敏、有才氣、精力充沛，并且為人友善。他卓越的表現(xiàn)，使他成為班里最出色的學生。他會提出很多的問題，我們也經(jīng)常進行討論，很快我們就成為伙伴。

后來的一些時間，朱棣文問我是否可以同意他成為我的助理研究生。在那時，我快要完成我的一些研究課題，并且很渴望去尋找一些新的課題，但是我不能確定新的研究方向。以我的辦事準則，我是不太想讓一個新的研究生加入的，但從另外一個角度，如上所述我怎么能拒絕像朱棣文這樣出色的學生呢？因此，我同意接受他并且我們開始一起工作，先從一個課題，再到另外一個課題。

在那些年代里，我們難免遇到挫折和失敗，我感到有才氣的朱棣文會提出比我更好的建議，來解決這些問題。

現(xiàn)在已過去30多年了，朱棣文作為一個物理學的研究員和教授，他獲得了巨大的成功，獲得了崇高的榮譽，獲得了諾貝爾獎，最近又被聘為勞倫斯伯克利國家實驗室主任。

他能做出如此優(yōu)異的成績，我以前是沒有想到的，但是，他做到了。然而，我作為他的導師，我仍然感到無比的自豪和驕傲，出于這個原因，非常高興為李劍君和曹慧所寫的《朱棣文》寫序，以此短序來表達我對他們努力將朱棣文介紹給廣大中國的讀者工作的敬意。

歐根·康明斯(Eugene D. Commins)

注：歐根·康明斯是加州大學物理系終身教授，世界實驗物理大師。

To the biegraplievs of Steven Clam:

I first met Steven Chu in 1970, when he attended my lectures in thermodynamics and statistical mechanics as a first-year graduate student in physics at the University of California,Berkeley. It did not take long for me to realize that he was very unusual: quick, brilliant,energetic, and outgoing, he distinguished himself as the best student in that class. He asked many questions, we entered into many discussions, and soon we became well-acquainted.

After some time, Steven asked me if I would accept him as a research student. At that moment, I had nearly completed several research problems, and was anxious to try something new; but I was unsure of what that new direction should be. Thus as a matter of principle, I was reluctant to take on a new research student just then; on the other hand how could I forego the opportunity with someone so outstanding as Steven? So, I agreed to accept him and we started to work together, first on one problem, then on another. For several years, we encountered only frustration and failure, and I began to feel that the very brilliant Steven Chu surely deserved a better advisor than me.　However, he remained faithful and determined, and eventually we found a fruitful and interesting path to pursue together-parity nonconservation in atoms.

Now more than 30 years have past, and Steven Chu has achieved great honor and distinction as a research physicist and professor, as a Nobel Prize winner, and most recently as Director of the Lawrence Berkeley National Laboratory. I have no right to claim any credit for his many brilliant accomplishments, most of which I never imagined could be possible before he actually did them. Still, as his teacher, I may perhaps be forgiven for feeling very proud of him.For this reason I am very glad that Li Jianjun and Cao Hui have written this biography of Steven Chu in an effort to introduce him to Chinese readers, and I am honored to contribute this short preface to their work.