May 1, 2025　　# LIRR Windows

I'm a regular LIRR (Long Island Rail Road) rider, and while I considered reading to be the primary benefit of using public transit, I did, more than occasionally, also have the interest of watching the outside world sliding backwards. It is in this secondary interest that I had my biggest complaint (and bewilderment) about LIRR: it has the least transparent windows I have ever seen on public transit. Some of the windows are so uniformly dirty-looking that it is as if they were made of frosted glass. I saw people saying that it was because LIRR trains run east-west, and therefore the south side of the windows is always under sunlight, which eventually degraded the glass. Not sure whether that was insider's knowledge or mere guesswork, and not sure what kind of glass (certainly not the type I have at home) could have undergone such degradation under sunlight (yes I know I'm a physics Ph.D., but that doesn't mean my knowledge covers every corner of the physical world. :-), but even if that's the case, I would still consider it poor management (or a poor choice of material), unless it's universal to all east-west running trains, which I highly doubt.

May 7, 2025　　# Polchinski's Memoir

Steven Weinberg is a physicist whom I admire a lot. I enjoyed reading his books and I resonated, to various degrees, with almost all his scientific and social views. After he passed away, I collected many reminiscences that his colleagues wrote, and I began to pay more attention to writings about him. Weinberg belongs to a generation that preceded, and, perhaps because of that, was generally less enthusiastic about, the rise of string theory. But Weinberg himself was rather supportive of string theory. As such, and since support from a person of his caliber carried huge weight, it is only natural that Weinberg appeared in Polchinski's memoir. In fact, Polchinski was among the first group of young faculty colleagues Weinberg hired to form his research circle at the University of Texas at Austin (which happened to be Polchinski's first post-postdoctoral job). I will share some of the Weinberg anecdotes in Polchinski's memoir.

May 8, 2025　　# Polchinski's Memoir

Steven Weinberg, if judged by his publications, was a largely solitary author. But he was by no means a solitary person. In fact, he had, according to Polchinski, a strong bond with and was proud of his research group, which held a weekly gathering dubbed the "family meeting". He also enjoyed lunch conversations with the group on subjects which Polchinski jokingly summarized as English history, Israeli politics, and DOS versus Windows. Those conversations were surely very casual, and only Israeli politics, if my reading is sufficiently exhaustive, received rather limited coverage in Weinberg's essay collections. Among the subjects, DOS versus Windows was particularly amusing and yet perhaps reflected a profound characteristic of Weinberg's research style ‒ namely he was, in Polchinski's words, "a notably text-oriented thinker", and "used very few figures in his books and papers". I would add one thing to the last point that I myself vividly remember: Weinberg, in his most famous textbook Gravitation and Cosmology, boldly deviated from the traditional geometrical pedagogy, and with that, "used very few figures" was completely natural. :-)

May 9, 2025　　# Polchinski's Memoir

Polchinski also portrayed Weinberg from the angle of personal interactions: "my first impression of him", he said, adding that he felt embarrassed to say, "was that he was a little slow" and "seemed to get stuck on things that seemed obvious". Though he continued by saying, a little bit insincerely I dare (and, to copy his words, feel embarrassed to) say, that he soon realized that this was part of Weinberg's genius since he never took anything for granted. This style of Weinberg's reminded me of Richard Feynman's habit of trying to derive everything in his own way. Sure enough, that sometimes also made Feynman, though far outsmarting most people he conversed with, look slow. In his best-seller memoir Surely You're Joking, Mr. Feynman!, he acknowledged he was slow in understanding people and often asked dumb questions, until eventually, he not only understood but might surprise people by catching their mistakes.

May 11, 2025　　# Ducks in 9/11 Memorial Pools

Saw two ducks in one of the 9/11 Memorial Pools at the World Trade Center complex. Quite a jump/fall to have landed there, and seemed not too far from another one!

May 14, 2025　　# Automation and Future

When I was a child, the future that both I and many of the future-telling books imagined was, judged with hindsight, childishly optimistic. Robots, for instance, were imagined to be universal helpers, through which people would be relieved from boring housekeeping tasks and live much more entertaining lives. It never came to my mind (at that time), or to the much-more-matured minds of those who wrote the future-telling books, that AI and automation technologies, of which robots are merely an example, while still quite far from being able to relieve people from housekeeping tasks, might nevertheless seize people's salary-earning jobs first, leaving the affected with no purchasing power for "more entertaining lives". This is, of course, just one example of failed social imagination, and I suppose it raises an immediate follow-up challenge to social imagination, namely (to quote from a video): If we automate everybody's job, who is going to buy all our sh*t?

May 15, 2025　　# Polchinski's Memoir

Polchinski mentioned in his memoir that he, at least in the early days of his research career, was shy of speaking about his work, because "I rarely felt that my work was important enough". That was a very familiar feeling that also haunted me, and I couldn't agree more with the reason for such shyness. Of course, my feeling that my work was not important enough was far more justified than his. :-) [Notes (supplimented on May 15, 2025): The "early days" were up to the late 1980s, when Polchinski was a lecturer at the University of Texas at Austin. And I suppose at least the reason for the shyness (if not the shyness itself) was only valid prior to his co-discovery of D-branes (in 1989).]