本文译自 Science News 文章With Steven Weinberg's death, physics loses a titan（2021 年 7 月 24 日）。中译文刊登于《数理人文》（公众号：math_hmat）。
作者：Tom Siegfried（Science News 特约记者）
译者：刘永昊（上海交通大学），黄振（中山大学）
2018 年温伯格在德州大学奥斯汀分校的办公室（照片来源：Tom Siegfried）
神话有它的泰坦；电影里有，物理学界中也有，只是现在少了一个。
史蒂文·温伯格（Steven Weinberg）于 7 月 23 日【编注：北京时间为 7 月 24 日】逝世，享年 88 岁。他是 20 世纪下半叶物理学领域的主要知识领袖之一；在 21 世纪的前 20 年，他也一直是学界的主导声音、积极的贡献者和活跃的教师。
在他那个时代的伟人名单上，温伯格总是与理查德·费曼（Richard Feynman）、默里·盖尔曼（Murray Gell-Mann）相提并论——对，仅有他们两人能和温伯格相提并论。
在他的同行中，温伯格是整个物理学乃至科学中最受尊敬的人物之一，散发着智慧和尊严。当他去世的消息在推特上传播开来，其他物理学家纷纷表达了失去他的悲痛。“他是我们这个时代最有成就的科学家之一，”其中一位评论道，“他是科学观的一位特别有力的代言人。”另一位则写道：“（他是）我们最优秀的物理学家之一，也是各类思想家中最优秀的代表。”
温伯格发展了一套统一电磁力和弱核力的理论，因此获得 1979 年诺贝尔奖。随后发展出的“物理学标准模型”——一部用数学语言描述亚原子粒子及其相互作用的杰作，就是建立在这个理论之上的。标准模型过于成功地解释了实验结果，以至于物理学家们长久以来一直在盼望哪怕发现任何一点偏差的机会，以期找到能够加深人类对自然的理解的“新”物理。
温伯格在物理学的其他领域也做出了重要的技术性工作，并撰写了相关领域（例如广义相对论、宇宙学和量子场论）的数本权威教科书。他是超弦理论的早期支持者，指出这是统一标准模型和广义相对论——爱因斯坦的引力理论——的万里长征中一条充满希望的道路。
早些时候，温伯格也意识到有必要和更广泛的受众交流。他1977年出版的畅销书《最初三分钟》（The First Three Minutes）向一代物理学家和爱好者介绍了“宇宙大爆炸”——宇宙的诞生，以及这个比喻背后的基础科学。后来，他就科学的本质及其与社会的交集写下了深刻而富有洞察力的论述。他长期为《纽约书评》（New York Review of Books）等刊物供稿，发表颇有创见的文章。
在 1992 年出版的《终极理论之梦》（Dreams of a Final Theory）一书中，温伯格表示，他相信物理学即将找到对现实真正的基本解释，即能够统一所有物理学的“最终理论”。广义相对论与量子力学，后者是标准模型的数学基础，它们明显的互不兼容让这个愿景难以实现。但在 1997 年的一次采访中，温伯格断言，上述困境反倒提供了一个重要的线索。“当你尝试把两者放在一起，就会发现自然法则并不允许我们过多地自由发挥。这对我们来说是巨大的帮助，因为它告诉了我们什么样的理论才可能是正确的。”
温伯格认为，尝试弥合相对论与量子力学的鸿沟“是巨大的进步，让我们可以仅仅基于数学计算和纯粹的思考发展出描述自然的正确理论。”
当然，在验证这些数学见解的正确性上，实验也是必不可少的。但标准模型与实验吻合得如此之好，以至于发现这些由新物理预言的微小偏差需要物理学家们的实验技术更上一层楼。“在通过实验揭示隐藏在标准模型下的真相之前，我们必须获得远超现有水平的实验能力，但前路漫漫。”他说，“我确信，如果保持现有的模式继续发展物理学......我们终将得出一个最终理论，但我大概率等不到这样一天，你们也很可能等不到。”
他说得没错，他确实没能见证终极理论的出现。也许，正如他有时承认的那样，没有人能等到那一天。或许我们缺乏的不是实验能力，而是智力。“人类可能不够聪明，无法理解真正的基本物理定律，”他在 2015 年出版的《给世界的答案》（To Explain the World）一书中写道；这是一部横跨古希腊和牛顿时代的科学史著作。
温伯格对科学史进行了深入的研究，写书并教授相关课程。《给世界的答案》一书旨在以现代知识审视古代和中世纪的科学。他因此招来了历史学家和其他人的批评，他们认为温伯格不理解历史学的意义，即依据当时的时代背景，而非事后诸葛亮地评价历史人物的所作所为。
温伯格固然完全明白历史学家们的观点，他只是不喜欢这种方式。对温伯格来说，人类理解“自然”的方式，究竟是如何从几百年前盲目的跌跌撞撞进化为依靠如今严密的研究体系的，这才是真正对我们有意义的科学故事。他相信，如果不清楚我们正身处何处，或是对一路走来的经验教训置若罔闻，那么我们迄今的历程就“没有意义”。
未来的科学史家也许仍会坚持基于温伯格所处的时代来评估他的工作。但毫无疑问，即使从未来的视角出发，温伯格的成就也将是巨大的。■
英文原文
Mythology has its titans. So do the movies. And so does physics. Just one fewer now.
Steven Weinberg died July 23, at the age of 88. He was one of the key intellectual leaders in physics during the second half of the 20th century, and he remained a leading voice and active contributor and teacher through the first two decades of the 21st.
On lists of the greats of his era he was always mentioned along with Richard Feynman, Murray Gell-Mann and … well, just Feynman and Gell-Mann.
Among his peers, Weinberg was one of the most respected figures in all of physics or perhaps all of science. He exuded intelligence and dignity. As news of his death spread through Twitter, other physicists expressed their remorse at the loss: “One of the most accomplished scientists of our age,” one commented, “a particularly eloquent spokesman for the scientific worldview.” And another: “One of the best physicists we had, one of the best thinkers of any variety.”
Weinberg's Nobel Prize, awarded in 1979, was for his role in developing a theory unifying electromagnetism and the weak nuclear force. That was an essential contribution to what became known as the standard model of physics, a masterpiece of explanation for phenomena rooted in the math describing subatomic particles and forces. It's so successful at explaining experimental results that physicists have long pursued every opportunity to find the slightest deviation, in hopes of identifying “new” physics that further deepens human understanding of nature.
Weinberg did important technical work in other realms of physics as well, and wrote several authoritative textbooks on such topics as general relativity and cosmology and quantum field theory. He was an early advocate of superstring theory as a promising path in the continuing quest to complete the standard model by unifying it with general relativity, Einstein's theory of gravity.
Early on Weinberg also realized a desire to communicate more broadly. His popular bookThe First Three Minutes, published in 1977, introduced a generation of physicists and physics fans to the Big Bang–birth of the universe and the fundamental science underlying that metaphor. Later he wrote deeply insightful examinations of the nature of science and its intersection with society. And he was a longtime contributor of thoughtful essays in such venues as theNew York Review of Books.
In his 1992 bookDreams of a Final Theory, Weinberg expressed his belief that physics was on the verge of finding the true fundamental explanation of reality, the “final theory” that would unify all of physics. Progress toward that goal seemed to be impeded by the apparent incompatibility of general relativity with quantum mechanics, the math underlying the standard model. But in a 1997 interview, Weinberg averred that the difficulty of combining relativity and quantum physics in a mathematically consistent way was an important clue. “When you put the two together, you find that there really isn't that much free play in the laws of nature,” he said. “That's been an enormous help to us because it's a guide to what kind of theories might possibly work.”
Attempting to bridge the relativity-quantum gap, he believed, “pushed us a tremendous step forward toward being able to develop realistic theories of nature on the basis of just mathematical calculations and pure thought.”
Experiment had to come into play, of course, to verify the validity of the mathematical insights. But the standard model worked so well that finding deviations implied by new physics required more powerful experimental technology than physicists possessed. “We have to get to a whole new level of experimental competence before we can do experiments that reveal the truth beneath the standard model, and this is taking a long, long time,” he said. “I really think that physics in the style in which it's being done … is going to eventually reach a final theory, but probably not while I'm around and very likely not while you're around.”
He was right that he would not be around to see the final theory. And perhaps, as he sometimes acknowledged, nobody ever will. Perhaps it's not experimental power that is lacking, but rather intellectual power. “Humans may not be smart enough to understand the really fundamental laws of physics,” he wrote in his 2015 bookTo Explain the World, a history of science up to the time of Newton.
Weinberg studied the history of science thoroughly, wrote books and taught courses on it.To Explain the Worldwas explicitly aimed at assessing ancient and medieval science in light of modern knowledge. For that he incurred the criticism of historians and others who claimed he did not understand the purpose of history, which is to understand the human endeavors of an era on its own terms, not with anachronistic hindsight.
But Weinberg understood the viewpoint of the historians perfectly well. He just didn't like it. For Weinberg, the story of science that was meaningful to people today was how the early stumblings toward understanding nature evolved into a surefire system for finding correct explanations. And that took many centuries. Without the perspective of where we are now, he believed, and an appreciation of the lessons we have learned, the story of how we got here “has no point.”
Future science historians will perhaps insist on assessing Weinberg's own work in light of the standards of his times. But even if viewed in light of future knowledge, there's no doubt that Weinberg's achievements will remain in the realm of the Herculean. Or the titanic.■
https://www.sciencenews.org/article/steven-weinberg-death-physics-electromagnetism-standard-model
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