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I know nothing except the fact of my ignorance.

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Posts on Threads

(2024.01 - 2024.04)

- by Changhai Lu -

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Earlier Posts <<<

January 1, 2024  # New Year Greeting

「The Cosmos is all that is or ever was or ever will be... our future depends on how well we know this Cosmos in which we float like a mote of dust in the morning sky.」

—— Cosmos (By Carl Sagan)   

Wishing everyone a happy and prosperous 2024

January 7, 2024  # Gardner and Landau

Renowned science popularizer Martin Gardner wrote in his autobiography that the secret of his success was his ignorance: "as a result, I had to struggle to understand what I wrote, and this helped me write in ways that others could understand". Such close connection between learning and teaching to which Gardner attributed his success is actually a fairly open "secret" sometimes known as the Protégé Effect, and is often tracked back to Roman philosopher Seneca's "while we teach, we learn".

But of course there are exceptions in which such connection was broken. A notable example is the great and genius Russian theoretical physicist Lev Landau who, according to his student E. M. Lifshitz, famously declared that he hardly remembered a time when he did not know calculus ‒ let alone the learning process. It is probably not too far fetched to relate this to the fact that his Course of Theoretical Physics, though an indisputable classic and a gem in physics, is notoriously difficult.

January 28, 2024  # On ChatGPT

A few words about ChatGPT (though I'm not a big user, partly due to what I'm about to say):

1. Quality is too unstable. Unlike talking to an intelligent person, in which every sentence has thoughts behind it, and even error is often heuristic and worth digesting, ChatGPT can be randomly wrong ‒ so randomly in fact that John Oliver in Last Week Tonight with John Oliver was not too exaggerating when saying "the problem with AI right now isn't that it's smart, it's that it's stupid in ways we can't always predict". Because of that, it's hard to trust anything ChatGPT provided without cross-checking, which severely diminishes its value (at least to me).

2. ChatGPT's language capability is so much better than Google Nest or Amazon Alexa and is indeed very impressive. With such capability, however, came a perhaps natural sense of companionship, and from that perspective two other issues stand out: too many disclaimers and too little recollection. Preceding answers with disclaimers as frequently as ChatGPT does just doesn't feel like something a companion would do. Lack of recollection of previous chats (in the sense of not being able to reference them) is even worse.

January 31, 2024  # On Twitter's Rename

A few words about the name change from twitter to X:

1. It made X the biggest (if not the only big) business entity whose domain mismatches name (Elon Musk does own X.com, but in order not to break billions of existing links, it can hardly do anything other than redirecting to twitter.com).

2. Twitter and its logo (blue bird), color (blue post buttons and check marks) and jargon (tweet) form a highly coherent and harmonious scheme. The intrusion of the black/white X logo ended the harmony.

February 5, 2024  # Writers' Professions

There is a saying that "writers aren't professionals", in the sense that, unlike other professionals, writers don't have special educations and review boards to establish a minimum level of competence. To make things even more "unprofessional", writers, due to insufficient earning out of writing, existed in all other professions, such as: governesses (The Brontës), tinker (John Bunyan), bank clerk (T. S. Eliot), stockbroker (Jules Verne), architect (Thomas Hardy), truck driver (Jack London), spy (Christopher Marlowe), advertiser (F. Scott Fitzgerald), tailor (Henry Miller), insurance man (Franz Kafka), physician (Anton Chekhov), and miner (Brett Harte), etc.

The above examples are from a book Casanova Was a Book Lover whose author himself contributed an example: school administrator (John Maxwell Hamilton). Last but hopefully not least, the humble owner of this Threads account, as an author of 15 (non-English) books, dare add yet one more example: software developer (Changhai Lu). :-)

February 11, 2024  # Feynman on Supernova

「It has been discovered that all the world is made of the same atoms, that the stars are of the same stuff as ourselves. It then becomes a question of where our stuff came from... It looks as if it was belched from some exploding star, much as some of the stars are exploding now. So this piece of dirt waits four and a half billion years and evolves and changes, and now a strange creature stands here with instruments and talks to the strange creatures in the audience. What a wonderful world!」

—— Richard P. Feynman   

It was from a three-night series of lectures Feynman (i.e. the "this piece of dirt" turned "strange creature") gave at University of Washington (Seattle) in 1963, which posthumously formed the book The Meaning of It All: Thoughts of a Citizen Scientist from which I quoted. Some readers might have noticed the similarity between it and the quote from Lawrence M. Krauss. They are indeed about the same remarkable scientific understanding, except that Feynman's version is perhaps less "poetic" in the ordinary sense.

February 14, 2024  # On Energy Saving Bulbs

"Back in my day", a bulb meant an incandescent bulb, and a 60W bulb would literally consume 60W of electricity (that's why it was labeled as such). But nowadays, we commonly use the so-called energy saving bulbs, for which a "60W Equivalent" bulb might only consume 7W or so of electricity. Have we finally achieved what numerous cranks had claimed innumerable times, namely the breaking of the law of energy conservation? Of course and unfortunately (or fortunately ‒ depending on how you view it) not...

What really happened is: incandescent bulbs emit visible light by heating up hard-to-melt metal such as Tungsten, but the visible light so emitted is only a small portion of the total radiation that goes out. On the other hand, an energy saving bulb can smartly trigger certain quantum processes whose emission is highly centralized in visible light, and therefore can emit same amount of visible light (that's what "60W Equivalent" means) with much less electricity consumption (such as "7W or so").

February 24, 2024  # On Einstein and the Bomb

Watched Netflix docudrama Einstein and the Bomb. Even with a certain level of over-familiarity I suppose I have on Einstein (after all, I have written a book and many articles on him), this docudrama still has its attractiveness: embeded in it were many Einstein videos which I, as mainly a book reader, have never seen before. On the downside, however, this docudrama quite predictably dramatized Einstein into the scientist stereotype that was more or less misleading. For instance, many commonly quoted Einstein writings, some on technical topics, were blended into monologues in front of people whose bewildered eyes indicated little grasp and interest. It is true that Einstein, when immersed in thoughts, might show the so-called absent-mindness and fail to read the air, but actively talking to people in the way the docudrama fashioned made him distortionarily nerdy and dummy. The docudrama would look more professional if it could steer away from such stereotypical imagination.

February 29, 2024  # Feynman on the Worst Times

「Looking back at the worst times, it always seems that they were times in which there were people who believed with absolute faith and absolute dogmatism in something. And they were so serious in this matter that they insisted that the rest of the world agree with them.」

—— Richard P. Feynman   

March 4, 2024  # My Criticism on Tip Culture

COVID-19 pandemic is by now in the rear view and quite diminished, but some effects in economics are as lasting as "Long COVID" in the wellness of some unfortunate personnel. Among those effects are the restaurant prices in which 50% increase (or more) from pre-pandemic level is by no means rare. While oil price may go up and down, restaurant prices seem only recognize one direction: up. Not only that, many a restaurant also raised tip rate from 15% to 18%. I understand the trend of inflation and the corresponding need to raise prices from time to time, but tip is proportional to price therefore is always already riding on top of the inflation train. Yet it still increased, and that is inflation squared. If we look long term ahead, then unlike prices themselves which, however improbable, may still drop under certain circumstances, tip rate will eventually solidify into social custom which is much more resistant to change ‒ except for an upward change as is happening right now.

March 8, 2024  # On Sci-Fi Film ARQ

Watched ARQ, a 2016 sci-fi film. Its theme, time travel, is among my favorites, and its peculiarity is that it involves a time loop: a group of violent people (among them the hero and the heroin) repetitively ran into a conflict inside a house with a sense of déjà vu that reflects the memory of previous loops. Eventually the hero and the heroin, with the help of the déjà vu, escaped the house and realized that the time loop was localized to the house. But they decided to go back and destroy the time machine so it wouldn't fall into the bad guy's hands. They then discovered on a computer that the loop has been run thousands of times, and their memory was reset every nine times. Knowing their memory would be reset again, the hero and the heroin left a desperate message on that computer regarding how to handle the time machine, in hope to guide themselves in future loops, and the films stops at the beginning of the next loop.

Two comments: 1. This story reminded me of a Star Trek: The Next Generation episode called "Cause and Effect", which also involves a time loop and a sense of déjà vu that eventually helped. 2. A better message to guide the hero and the heroin in future loops should be, in my opinion, to simply urge them to escape the house rather than handle the time machine. The fact that the time loop was localized to the house and has been run thousands of times, means the time machine is inconsequential to the outside world (in fact, the bad guys need the hero to manipulate the time machine, which will make it even more inconsequential once the hero and the heroin escape).

March 15, 2024  # On Polar Star

It might come as a surprise to some that (northern) "polar star" is not the name of a fixed star, but rather a title assigned to whichever star that is sufficiently bright and happens to be close enough to Earth's northern axis of rotation ‒ just like a crown is not on top of a singular head forever, but instead is coronated to whoever happens to ascend to the throne.

The reason "polar star" changes is twofold: 1. Earth's axis of rotation is not fixed but, mainly due to gravitational tugs of the Moon and Sun on Earth's equatorial bulge, has a slow precession, causing the northern axis slowly pointing away and eventually picking up a different star as the "polar star"; 2. Stars themselves are moving. It is not uncommon for a star to hold the "polar star" title for thousands of years, and it is possible to have periods during which no sensible "polar star" exists.

March 22, 2024  # On US Founding Fathers

Contrary to the silliness and irrationality that are so characteristic of many high-profile contemporary US politicians, the founding fathers of the United States, though hundreds of years prior to us, are surprisingly intelligent and rational. Growing up in the historical era generally known as the Age of Reason, in which Newtonian science was esteemed as the highest achievement of the human mind, both the founding fathers and the Constitution of the United States they put together were influenced by Newtonian science.

As a background to this observation that was known to many historians, Benjamin Franklin, who himself was a scientist, admired Newton and even tried to meet Newton when he was in London as a young man; Thomas Jefferson had Newton’s Principia as one of his favorite books; John Adams studied Newtonian natural philosophy as an undergraduate at Harvard College; James Madison studied the science of Newton as an undergraduate at Princeton.

March 28, 2024  # On Bitcoin

Bitcoin's exchange rate recently exceeded $70,000, marking a new record in bubble size. A quick way to see its "bubbliness" is to notice that the total amount of conventional money in the world is in the order of tens of trillions of US dollars, and the total "value" of bitcoin, with the current exchange rate, already exceeded 1% of that amount. Such total "value", however, has never been realized (not even close) in commodity purchasing because bitcoin doesn't have the overall purchasing power on par with its highly bloated exchange rate, and the only reason the bubble is so resilient is that only a tiny fraction of bitcoins ‒ no more than what other bitcoin players are willing to absorb ‒ were actually used. To make things even worse and fated, mining a bitcoin as of now consumes over 150,000 kWh of electricity (costing over $20,000), which means bitcoin CAN ONLY EXIST in bubble state, since only a sufficiently bloated exchange rate (over $20,000 as of now) can justify bitcoin mining.

April 5, 2024  # A Minor Earthquake

Felt some minor vibrations inside a 20-story office building this morning, which turned out to be the effect of a 4.8 magnitude earthquake centered in Whitehouse Station, New Jersey, about 45 miles west of downtown New York City. This is the second time I have experienced a so-called "felt" earthquake (the previous one being the 5.8 magnitude Virginia earthquake on August 23, 2011).

Contrary to the intuitive feeling that tall structures might be shakier, modern high-rise buildings are actually quite resilient, perhaps much more so than low-rise buildings, to earthquakes, because: 1. High-rise buildings vibrate at frequencies too low to resonate with earthquake vibrations; 2. Modern high-rise buildings have adopted technologies (such as base isolators and seismic dampers) to further reduce vibrations and absorb earthquake energy.

April 8, 2024  # A Partial Solar Eclipse

With a pair of solar eclipse glasses which filters out IR, UV, and about 99.99% of visible light, today is the third time I have watched a solar eclipse ‒ a 90% partial eclipse this time from my backyard. The weather was reasonably cooperative, with scattered clouds not posing too much trouble. Seeing through the solar eclipse glasses, the orange-colored sun bears a significant similarity to an eclipsed moon, but excerts enough heat onto my face to incessantly remind me of its power.

The two other solar eclipses I had the luck to watch are: 1. A 97% partial eclipse when I was in middle school (in China). I had no solar eclipse glasses at that time, and even 3% of the sun was far too much for naked eyes. On the fortunate side, however, 97% was significant enough to cause noticeable ambient dimness, and that was memorable. 2. A 72% partial eclipse on Aug 21, 2017 which I watched from the rooftop of the office building but under nearly impossible condition. It was not too impressive.

April 23, 2024  # On Brightline West

I'm a big fan of railroads since I was a child (and was in China). The chance of a train ride back then (and back there) was quite rare, in fact rare enough to excite me into sleeplessness the night before the ride. I'm an even bigger fan of HIGH-SPEED railroads but ironically had even less of a chance, in fact ZERO chance, for a ride in the otherwise considered technologically advanced United States. I was therefore very happy to know that Brightline West, a high-speed rail route from Las Vegas to Los Angeles, broke ground yesterday.

Brightline West was set to be completed in 2028 (surprisingly speedy in US standard). Though I'm not naïve enough to count on the planned completion date for so large a project, as California High-Speed Rail has notoriously demonstrated that a completion date can "year by year recedes before us" like in one of the ending sentences of The Great Gatsby. But nowadays, Brightline is perhaps the only US railroad company that has actual success stories in railroad construction. So fingers crossed!

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