【2018.03.22】狄拉克纪念文集摘录

　　狄拉克纪念文集《Paul Adrien Maurice Dirac: Reminiscences about a great physicist:》分为三个部分，第一部分Human side，主要讲述狄拉克教授生活中非科学家的一面，这部分的文章记录了许多与狄拉克教授有关的趣事，我摘录了其中一些。

　　翻译均为个人翻译，恳请斧正。每段的作者与文章名附在英文原文最后括号内。

Simplicity and clarity were among Professor Dirac's greatest attributes. One day, going around a small lake in Matheson Hammock Park in Coral Gables, I counted seven birds and told him I saw seven birds, and he said, 'No, there are eight.' I asked him, 'Where is the eighth?' He said, 'One just dove.' (Kursunoglu, B. N., A memorial to P. A. M. Dirac)

　　清晰、简洁是两个狄拉克教授最为美好的特质。一天，我们在Coral Gables的Matheson Hammock公园，围着一个小湖散步时，我数到了七只鸟，然后把结果告诉了他。他说，“不，有八只鸟。”我问他，“第八只在哪儿？”他回答，“有一只刚刚潜进水下了。”

On matters of beauty and physics, Dirac has always been ahead of everybody else. On one occasion during a dinner in Fort Lauderdale, I said, 'Paul, just the other day, some people asked about my religion. I indicated to them that beauty was my religion, such as beauty in arts, in sciences, in nature, and in woman. Sometimes, I tell them that Professor Dirac has the same religion. Do you think I made a mistake?' Dirac added immediately, 'I shouldn't think so,' and he then asked, 'You aren't going to advertise this, are you?' With tongue in cheek, I replied, 'Of course not!' (Kursunoglu, B. N., A memorial to P. A. M. Dirac)

　　若提及物理与美这个话题，狄拉克总是领先于众人的。有回在Fort Lauderdale的晚宴上，我说，“保罗，就在那天，有些人问到我的宗教信仰。我表示我的信仰是美，比如艺术之美，科学之美，自然之美，还有女性之美。有时，我告诉他们狄拉克教授也有着同样的信仰。你觉得我说错了吗？”狄拉克教授立刻回答，“我不该这么认为。”然后他接着问，“你没打算把这个广而告之吧？”我促狭道，“当然不会！”

It was soon after my arrival; we were having lunch at one of these restaurants, when a tall, slender young man entered the dinning room, looked at Eugene and greeted him. He looked lost, and sad. I asked who he was, still standing undecided and none too happy looking. I was told, he was an English physicist, whom Eugene knew in Götthingen, where they used to have their meals together. 'He does not like to eat alone.' 'So why don't you ask him to join us?' This was how I met Paul Dirac. (Dirac, M., Thinking of my darling Paul)

　　那时我刚到普林斯顿不久；我们在其中的一家餐厅吃饭，期间一位身材修长纤细的年轻人走进了餐厅，看见了尤金，并和尤金打了招呼。他看上去失落而悲伤。当时我还未入座，犹豫不决，且看上去也不是很开心。我询问有关他的身份，然后被告知他是一位英国物理学家。尤金在哥廷根认识了他，在哥廷根他们曾一起用餐。“他不喜欢自己一个人吃饭。”“那你为什么不让他和我们一起吃？”这就是我遇见保罗.狄拉克的经过。

Dirac had his sabbatical leave from Cambridge University. He came to the U.S.A. via Russia, where he visited some of his Russian friends. At one of our meals, he spoke about having to go up to New York, to buy himself a winter coat. He had left his in Russia - one of his great friends there had none. The friend was Tamm, the year 1934 when shortages in Russia were many and sever. He obviously dreaded a shopping day, while I was, and still am, an enthusiastic shopper. (Dirac, M., Thinking of my darling Paul)

　　狄拉克在学术假期间离开了剑桥。他经由俄罗斯到达美国，在俄罗斯，他见了一些他的俄罗斯朋友。一次，在我们共同用餐时，他提到他要去往纽约给自己买一件新的冬大衣。他把他之前的那件留在了俄罗斯——他的一个俄罗斯朋友一件冬大衣都没有。这个朋友是塔姆。1934年，俄罗斯经历了一次严重而广泛的物资短缺。狄拉克很明显惧怕购物日，而我是个购物狂，直至今日也如是。

I asked him once if he ever got tired after lunch and wanted to take a nap. He said he did nap in his chair or put his head on his desk to sleep to refresh himself for the rest of the day. I asked him, 'When you are working, do you ever get stuck?' He said, 'All the time.' (Kursunoglu, S. A., Dirac in Coral Gables)

　　我问他（狄拉克）他是否会在午餐后觉得疲惫想要小憩，他说他会在自己的椅子上小憩，或者头枕着他的桌子睡觉，让自己在一天余下的时间里都能清醒一些。我问他，“你在工作时，是否经历卡壳的情况？”他说，“一直如此。”

At the end of the conference, which lasted only four days, Mary was returning to Princeton. Behram was driving the Diracs to the airport on the new expressway. I-95 was a brand-new road to the airport. We were pressed for time, and Mary was worried that she might mess her plane. I said to Behram, 'The next exit is the airport.' Professor Dirac, in a stern tone, said to me, 'Let's not have back-seat drivers.' That was the only time I heard him speak to me in that tone of voice in the nearly 16 years I knew him. He was always very sweet and gentle with me. (Kursunoglu, S. A., Dirac in Coral Gables)

　　在四天的学会结束时，玛丽（狄拉克的女儿）要回普林斯顿了。贝拉姆（该文作者的丈夫）开车走新的高速公路送狄拉克夫妇去机场。我们有些赶时间，玛丽担心她可能错过她的飞机。我告诉贝拉姆，“下一个出口就是机场。”狄拉克教授语气严厉地对我说，“我们还是别让后座乘客来驾驶。”我与他认识近16年，这是他唯一一次用这样的语气与我说话。他对我的态度一向是十分温柔友善的。

Before the 1969 epidemic destroyed thousands of coconut trees in Miami, we had many in our back yard. Professor Dirac was fascinated with them. Some weekends, we had cook-outs for him in our garden by the pool, and he would easily stretch his arm and pick a coconut from a tree. Even though they were still green, he would crack them with an axe, split them into halves, drain the white coconut milk through a strainer into a glass, and drink it right away. He said it was delicious. Then, he would scoop out the tender coconut meat with his pocket knife and eat some of it. He always ate very little and very slowly. (Kursunoglu, S. A., Dirac in Coral Gables)

　　在1969年的传染病摧毁了迈阿密的数千株椰子树前，我们的后院里种了很多这种植物。狄拉克教授很喜欢它们。有时周末我们会为他在花园的水池旁边举行露天烧烤会，他就只要伸手就能很轻松地从树上摘下一颗椰子来。即使叶子还是青色的，他也会用斧子凿开它们，把它们分成两半，用一个滤器把白色的椰子水流进玻璃杯里，然后立刻喝掉它。他说这味道很不错。然后，他会用他的小折刀把柔软的椰子肉挖出来，吃掉其中的一些。他总是吃得很少，也吃得很慢。

I do not recall how Dr. Rhona and Mrs. Dirac first met, but they became immediate friends with a common Hungarian heritage. Dr. Rhona worked as a research scientist at the marine Laboratory. While the two of them spoke together in Hungarian, Professor Dirac would watch with amusement. He used to say to me, 'Moncie (as he called Mrs. Dirac) likes to talk Hungarian.' Although he did not speak Hungarian, it was of little matter, since, even when conversation was in English, he used to fall asleep in his seat. Often, though, when he heard his name mentioned, he would open his eyes and look around, momentarily interrupting his nap.

We have a comfortable 'Florida Room' on one corner of our house. Behram uses it as his study. One day while Professor Dirac was visiting, he dozed off while sitting in one of the heavy, padded chairs he favored. When I came into the room and noticed his eyes open, I asked if he had had a nice rest. He said he could not sleep, because Behram was chewing gum and was making a lot of noise. Behram had quit smoking at that time and had started chewing gum as a substitute. (Kursunoglu, S. A., Dirac in Coral Gables)

　　我不记得罗纳博士和狄拉克夫人的初见情形，但她们因为同为匈牙利出身，所以她们立刻就成为了朋友。罗纳博士在海洋实验室作为一个科学家进行研究。当她们俩用匈牙利语交流时，狄拉克教授会饶有兴致地看着。他曾经告诉我，“曼琪（他如是称呼狄拉克夫人）喜欢讲匈牙利语。”尽管他不说匈牙利语，这也根本无关紧要。因为，哪怕对话是以英语进行的，他也会在自己的座位里睡着。不过，通常他听到有人提到他的名字时，他会暂时停下小憩，睁开眼然后四下环顾。

　　在我们家的一个角落里，有个很舒服的“佛罗里达室”。贝拉姆把这个房间做学习研究用。一天狄拉克教授来做客，当他坐在一个他喜欢的厚重的、加了衬垫的椅子上时，他打起了瞌睡。当我进入房间时，我发现他的眼睛是睁开的。我问他休息得如何，他说他没能睡着，因为贝拉姆嚼口香糖发出了很大的噪音。那时贝拉姆戒了烟，并开始嚼口香糖作为替代。

One Saturday, Professor Dirac went with Behram and my son to an afternoon matinee to see the film Swiss Family Robinson. When the movie was over and they came out, they saw that the two of them were the only adults at the show. (Kursunoglu, S. A., Dirac in Coral Gables)

　　在一个星期六，狄拉克教授和贝拉姆带着我的儿子去了午后场看《海角一乐园》的电影。当电影结束，他们出来时，发现全场只有他们两个大人。

Despite his quiet ways, he was always full of surprises. One day, Mrs. Dirac asked me to go with them to Coconut Grove to an antique shop run by Mr. Campbell and his mother. Mrs. Dirac and I often went shopping together, and Professor Dirac liked to tease her. He would say, 'Did you go shopping with Sevda today? Tomorrow you will want to go back and return what you bought.' On this particular occasion, she wanted to make a major purchase, so she took her husband along. They looked at several paintings in the front room of the shop, before moving to the darker back room to see the larger paintings. Mrs. Dirac pointed to a big oil painting on the wall and said to me, 'You have better eyes, look at it. What do you think?' It was like a Toulouse-Lautrec painting; a lady wearing a long evening dress with yellow, orange, and red floral print.

I remarked, 'This is exactly like the dress I wore to the conference party last night!' Professor Dirac replied, 'Yours was low cut.' His answers were always short and to the point. (Kursunoglu, S. A., Dirac in Coral Gables)

　　尽管狄拉克教授是个性格安静的人，但他也总是充满惊喜。有一天，狄拉克夫人让我和他们一起去Coconut Grove上Campbell和他的妈妈共同经营的古董店。我和狄拉克夫人经常一起购物，而狄拉克教授喜欢戏弄她。他会说，“你今天又和塞弗达一起去购物了？明天你就会想把你今天买的东西退回去的。”而这一次，因为狄拉克夫人想要买的东西比较重要，所以她拉上了她的丈夫一起。在他们去往比较昏暗的后厅去看更大的绘画作品前，他们在商店大厅里先看了几幅画。狄拉克夫人指着墙上的一幅油画跟我说，“你眼光更好，看看这幅，你觉得怎么样？”那好像是一幅图卢兹-洛特雷克的作品：一位女士，穿着长长的印着黄色、橙色，和红色花纹的晚礼服。

　　我评论道，“这件衣服和我昨晚在会议聚会上穿的一模一样！”狄拉克教授回答，“你那件是低胸的。”他的回答总是简洁明了、一语中的。

Professor Dirac sat comfortably in a chair, looking out their living room window while having his drink. He would sit there peacefully, sometimes closing his eyes and sleeping quietly, even when others around him were talking or moving about. His movements were very gentle. He would get up slowly, walk slowly, take a step forward slowly, and speak slowly, as if he were counting every word he was using to express himself.

He had graceful hands with long, slender fingers covered with transparent white skin, like fine porcelain that could break easily. At the dinner table, there was harmony between his hands and the fine crystal glasses when he reached out to drink his water - always without ice. (Kursunoglu, S. A., Dirac in Coral Gables)

　　狄拉克教授舒服地坐在椅子上，一边享用饮料，一边看向客厅窗外。他会安静地坐在那里，有时闭上眼睛安然睡觉，哪怕周围有人在说话或走来走去。他的动作总是很轻柔。他会慢慢起身，慢慢行走，慢慢向前迈步，慢慢说话，仿佛他在计算他用来表达自身的每个词似的。

　　他有一双优雅的手，修长的手指覆盖着晶莹洁白的皮肤，好像易碎的瓷器。在晚餐时，当他伸手举杯喝水——总是不加冰——的时候，他的双手与精致的水晶杯之间存在着一种协调的美感。

The conference party was in the ballroom of the Surf Club in Surfside, near Miami Beach. The orchestra started playing and, somehow, Professor Dirac was asked to start the dance with me. When I got up and walked to the dance floor with him, I did not know which way to turn. He said to me, 'This way, I have to lead'. (Kursunoglu, S. A., Dirac in Coral Gables)

　　会议聚会在Surfside的Surf Club的舞会厅，那里靠近Miami Beach。乐队开始了演奏，然后由于一些经纬，狄拉克教授被要求与我一起开始跳舞。当我起身和他一起走向舞池，我不知道该向哪一边转身。他告诉我，“这一边，我得领舞。”

I frequently asked Professor Dirac's advice. At that time, I was one of the women who went back to school to continue their education. I had finished my B.A. degree in mathematics, and, with Professor Dirac's encouragement, I was working toward a master's degree, also in mathematics. Sometimes it was very hard to pursue my studies with my socially demanding lifestyle. Since we live nearby, I often liked to walk to the campus to use the library or study in my office. I found my studies very exciting, and I enjoyed spending my free time learning higher mathematics. At the same time, I was afraid of what others would be thinking about my behavior. So, one day, I asked Professor Dirac about it. He said to me, 'You come first. Think about yourself first. If nobody gets hurt, do it.' (Kursunoglu, S. A., Dirac in Coral Gables)

　　我时常向狄拉克教授寻求建议。那时，我是重返学校接受教育的女性之一。我完成了数学本科学位，然后，在狄拉克教授的鼓励下，我开始攻读数学硕士学位。有时，因为我的生活方式对社交要求非常严格，我发现要同时追求学业就变得十分困难。因为我们住得很近，所以我经常走去学校，然后在图书馆或者我的办公室里学习。我的学习相当振奋人心，我也很享受在空闲时间了解更为高阶的数学。但同时，我也担心他人对我这样行为的看法。所以有一天，我就此向狄拉克教授请教。他告诉我，“你自己是最重要的，首先考虑你自己。如果没有人会因此遭受损失，就去做。”

The female undergraduate student who came to his office and handed him a rose, commenting only that it was to respect and honor him, and then leaving without introduction. (Lannutti, J. E., Recollections of Paul Dirac at FSU)

　　一位本科女生去了他的办公室，并给了他一朵玫瑰。这位女生只是说这么做是为了向他表示尊敬，然后没有做自我介绍就离开了。

My first non-family visitors after my heart surgery were Paul and Margit and Paul's strong recommendation that I do more walking for exercise.

Then, for more than a year, walking with Paul 4-to-10 miles on the forest fire trails of the Appalachicola National Forest each Saturday and Sunday - Lost Lake, Dog Lake, Silver Lake, behind the Aenon Church, around Lake Bradford, etc. Contemplating nature from a lakeside.

　　除了我的家人以外，最先在我接受心脏手术后来看望我的就是保罗和玛吉特，然后保罗强烈建议我多散步来锻炼身体。

　　在那之后，超过一年的时间里，我和保罗一同，每个周六周日都会沿着Appalachicola国家森林的森林的救火道走上4-10英里（约6.4-16公里）——地名不逐一翻译，等等。在湖边思考自然。

（以下两个故事来自本书第二部分More science side，但故事内容和科学没什么大关系）

Once Dirac and E. M. Forster met at a dinner in Cambridge. The tale of the exchange between them, in its entirety, has often been told.

D. What happened in the cave?

F. I don't know

That version is apocryphal, however. Peierls has told me that he asked Dirac what really was said, and got this answer.

D. Was there a third person in that cave?

F. No.

(Pais, A. Playing with equations, the Dirac way)

　　一次，狄拉克与E.M.福斯特（英国作家，著有《天使不敢涉足的地方》、《印度之行》、《莫里斯》等作品）在剑桥共进晚餐。有关他们之间完整对话的故事经常被提及：

　　狄拉克：在洞穴里发生了什么？（这里讨论的是《印度之行》的小说情节：阿德拉小姐和穆尔夫人一同进入马拉巴山洞，前者在洞中神志错乱，误以为没有一同进入山洞的男主角阿齐兹对她图谋不轨，于是诬告阿齐兹。）

　　福斯特：我不知道。

　　然而，这个版本的真实度并不高。皮尔斯告诉我他问了狄拉克究竟确切对话是怎样的，然后得到了如下回答：

　　狄拉克：洞穴里有第三个人存在吗？

　　福斯特：不。

The other story is not about Dirac, but one that I have heard Dirac tell more than once, with relish. In a small village, a newly appointed priest went to call on his parishioners. On a visit to a quite modest home, he was received by the lady of the house. He could not fail to notice that her place was teeming with children and asked her how many the couple had. Ten, she replied, five pairs of twins. Astonished, the priest asked: You mean you always had twins? To which the woman replied: No, Father, sometimes we had nothing. Precision at that level had an immense appeal to Dirac. (Pais, A. Playing with equations, the Dirac way)

　　接下来这个故事不是关于狄拉克的，但我从狄拉克那里听到不止一次，他每次讲起都十分惬意。在一个小村里，有个新近被指派的神父去拜访他的堂区居民。一次他来到一家相当简朴的家庭，他见到了这家的女主人，也无法对家里成群的孩子视而不见。他问女主人，他们夫妻有多少孩子。十个，女主人回答，五对双胞胎。神父很惊讶：你的意思是你们总是生双胞胎？对此，女主人回答：不，神父，有时候我们什么也没生。这种程度的精确表述，对于狄拉克而言总是有很强的吸引力。