vttoth

I am a software developer and author of computer books. I also work on some problems in theoretical physics. For more information, please visit my personal Web site at http://www.vttoth.com/.

Jan 282024
 

I first bought a hybrid (a Honda Civic) in 2004. I loved that car; it served us faithfully for 10 years. Our more recent Hondas were not hybrids, but the reasons were eminently practical: hybrids were in short supply, conventional gasoline cars were cheaper, and we use the car very little in any case, so…

Having said that, I certainly contemplated the idea of buying an all electric vehicle, but every time I think it through, I decide against it. Today, I saw a map that perfectly illustrates my lack of enthusiasm. Here it is:

This map shows the locations of supercharger stations where you’d have to stop for a 20-30 minute recharge, in order to complete a cross-country trip across the United States in a Tesla automobile.

In contrast, here’s a map of an actual trip I took in my Civic Hybrid back in 2005, along with the approximate locations where I stopped for gas (reconstructed from old receipts):

What can I say? I think EVs are great when you live in the suburbs and use your car for shopping and commuting to work. If I lived, say, in Kanata and commuted daily to work at, say, Place du Portage in Gatineau, purchasing an EV would make an awful lot of sense. But that’s not where we live or how we commute. We live on Ottawa Lowertown, which is to say almost downtown, we work at home, we use the car only occasionally, but as this example demonstrates, sometimes for lengthy road trips. EVs are not great for lengthy road trips. I am used to the idea of driving to Montreal Airport and back without worrying about stopping for gas. Or driving to Toronto non-stop.

And then, of course, there are the dreaded Canadian winters. It’s one thing to use waste heat from a gasoline engine to heat the interior of a car. It’s another thing to waste electric power stored in a battery for this, converting electricity inefficiently into heat, at the expense of range already reduced by the effect of cold weather on the batteries. And while heat pumps can help, there are no miracles when the outside air temperature is closer to -40 than -30 Centigrade, which is a not altogether uncommon occurrence (though it is certainly becoming less common) in these parts of Canada.

And then there’s the question of where the electric energy comes from. Renewables are okay, nuclear would be great. But too much of the electricity, even here in nuclear-rich Ontario, comes from natural gas fired plants. That’s not so great.

So for now, it’s either gasoline-powered or hybrid vehicles for us. EVs may be in our future, but I am not yet too keen on them, to be honest.

 Posted by at 3:05 pm
Jan 242024
 

Someone sent me a link to a YouTube podcast, a segment from an interview with a physicist.

I didn’t like the interview. It was about string theory. My dislike is best illustrated by a point that was made by the speaker. He matter-of-factly noted that, well, math is weird, the sum of \(1 + 2 + 3 + …,\) ad infinitum, is \(-\tfrac{1}{12}.\)

This flawlessly illustrates what bothers me both about the state of theoretical physics and about the way it is presented to general audiences.

No, the sum of all positive integers is not \(-\tfrac{1}{12}.\) Not by a longshot. It is divergent. If you insist, you might say that it is infinite. Certainly not a negative rational number.

But where does this nonsense come from?

Well, there’s the famous Riemann zeta-function. For values of \(s>1,\) it is indeed defined as

$$\zeta(s)=\sum_{n=1}^\infty \frac{1}{n^s}.\tag{1}$$

It is a very interesting function, at the heart of some unresolved problems in mathematics.

But the case of \(s=-1\) (which is when the right-hand side of the equation used to define \(\zeta(s)\) corresponds to the sum of all positive integers) is not an unresolved problem. As it is often presented, it is little more than a dirty trick befitting a cheap stage magician, not a scientist.

That is to say, the above definition of \(\zeta(s),\) as I said, is valid only for \(s>1.\) However, the zeta-function has what is called its analytic continuation, which makes it possible to extend the definition for other values of \(s,\) including \(s=-1.\) This can be accomplished utilizing Riemann’s functional equation, \(\zeta(s)=2^s\pi^{s-1}\sin(\tfrac{1}{2}\pi s)\Gamma(1-s)\zeta(1-s).\) But the right-hand side of (1) in this case does not apply! That sum is valid only when it is convergent, which is to say (again), \(s>1.\)

A view of the Riemann zeta-function, from Wikipedia.

So no, the fact that \(\zeta(-1)=-\tfrac{1}{12}\) does not mean that the sum of all integers is \(-\tfrac{1}{12}.\) To suggest otherwise only to dazzle the audience is — looking for a polite term here that nonetheless accurately expresses my disapproval — well, it’s dishonest.

And perhaps unintentionally, it also shows the gap between robust physics and the kind of mathematical games like string theory that pretend to be physics, even though much of it is about mathematical artifacts in 10 dimensions, with at best a very tenuous connection to observable reality.

 Posted by at 10:48 pm
Jan 192024
 

Japan’s SLIM (Smart Lander for Investigating Moon) made it to the lunar surface. Well… sort of. It accomplished its main goal of a targeted soft landing.

Unfortunately, its solar panels are non-operational. It’s unclear for now why (one speculation I read is that the lander may have tipped over after landing). Its batteries can power it only for a few hours. They’re hoping that perhaps later in the lunar day, or in a next lunar cycle, the lander will get sunlight from the right direction to be able to recharge its batteries after all.

Even so, Japan is now officially the fifth country to have landed a spacecraft on the Moon that remained (at least partially) operational on the lunar surface.

 Posted by at 2:01 pm
Jan 182024
 

I gave a brief invited talk today via Zoom, participating in a workshop on cosmological models, organized by Complutense University of Madrid, Spain.

The subject of my talk was John Moffat’s theory of gravitation, MOG/STVG, to which I made significant contributions myself over the past 18 years, in an on-going collaboration with John. Judging by the questions that followed my short presentation, I think it was reasonably well received.

The workshop was streamed live on YouTube, and the video is archived.

 

 Posted by at 9:25 pm
Jan 152024
 

I offered this gloomy prediction before I am offering it again, though it gives me no pleasure: World War 3 is long overdue.

When I was growing up in the 1960s and 1970s, nuclear Armageddon was seen as almost inevitable someday. Back in 1970, when I was in the second grade, chances were no sane adult believed that the world would persist mostly in peace, with no major conflict between great powers, all the way up to the year 2000 and beyond.

Yet here we are, in 2024, now in the 79th year of the historical epoch that should rightly be called pax Americana: an imperfect, yet unprecedent period of peace, a rules-based world order that brought prosperity, freedom and security to billions. Not everyone, to be sure, but still, it was an era without precedent. The only comparable period of time that I can think of is also from relatively recent history: the decades between 1849 and 1914, which gave birth to the modern world, streetcars and electric subways, lightbulbs and radios, airplanes and labor unions, telephones and civil rights.

It is true that century after century, humanity has become more peaceful: that in any given century since the dawn of written history, your chances of dying as a victim of violence were ever so slightly less than in the preceding century. But that did not put an end to devastating war. And an all-encompassing, devastating war is long overdue, if history is any guide.

In fact, I very much worry that by the reckoning of some future historians, World War 3 might already be under way. We simply haven’t recognized it just yet.

Consider World War 2. When did it begin? Well, most official accounts I suppose mark September 1, 1939, when Hitler’s Third Reich attacked Poland, as the start date. But that’s a very Euro-centric view. I daresay that, in reality, World War 2 actually began on July 7, 1937 at the bridge known to Europeans as the Marco Polo bridge in Beijing, China. It was this incident that started what some call the Second Sino-Japanese War, but it really is the first major military conflict marking the beginning of the global war between 1937 and 1945.

Of course no one in July 1937 surmised that these were the first shots fired in a war that will leave tens of millions dead, Europe devastated, and culminate in the first (and to date, only) use of nuclear weapons in anger. Not even in September 1939 was it a foregone conclusion that the world entered another World War; indeed, for months thereafter, much of the Western press was talking about a “phony war”.

Things changed after the collapse of France, the Battle of Britain, Barbarossa and Pearl Harbor, of course. But it was a gradual process of recognition. Only in hindsight did we attach a firm date (even if it is the wrong date) marking the beginning of the world war.

So where are we now? War in Ukraine continues. Putin is undoubtedly enraged that Ukraine receives substantial assistance not just from the West in general, but from the Baltic states that not too long ago were part of the Soviet Union, places he thinks he owns. Meanwhile, what began as an unprecedented terrorist attack on Israeli civilians in early October is rapidly widening into a regional war, with US and UK forces now attacking Houthi facilities in Yemen, bases that were used to carry out unprovoked attacks on commercial shipping in the region. Iran, of course, is actively involved in all this even as they are entering an unholy alliance, dubbed the “axis of resistance”, uniting Iran, Iraq, Syria, Lebanon and Yemen, with support from Russia and North Korea.

These conflicts are unlikely to go away in 2024. If anything, they are more than likely to escalate.

And I don’t think it’s too far-fetched to consider the very possibility that nuclear weapons will soon enter the stage.

Israel of course is one of the undeclared nuclear powers of the world. Should they feel existentially threatened, I don’t think they’d hesitate to use nukes against their major opponents.

Iran, as far as we know, is not a nuclear power just yet, but they are “almost there”. Would they use nukes merely as a deterrent, or would they deploy nukes against Israel? The ayatollahs are just crazy enough to do that, I fear.

Russia is of course one of the nuclear superpowers of the world. So far, they refrained from using nukes in Ukraine, but how close are they to take that step? They have already been using chemical weapons at a rising rate according to several reports that I have seen.

And then there is Ukraine itself. Though the country gave up its arsenal of inherited Soviet-era weapons, they certainly have the scientific and technological capability to develop a nuclear weapon in a short period of time. Are they working on it already? If so, how close are they and what will be the intended use? Deterrent? Battlefield deployment? And how would Russia react?

Meanwhile, the West is preoccupied with increasingly polarized politics, putting “conservative” against “progressive”, while undermining perhaps fatally the values of liberal democracy. Indeed, there are leaders like Hungary’s Orban who proudly declared themselves and their political schools of thought “illiberal”. It’s not exactly clear which part of traditional liberalism they reject, though quite possibly it’s all of them: who cares about the rule of law when they prefer the laws not apply to them, who cares about freedom of enterprise when their oligarchic cronies want no competition, who cares about civil rights when those pesky citizens have the audacity to criticize them? But if “illiberal” marks predominantly the conservative right, their “woke” counterparts from the progressive left, dubbed “liberal” though their attitudes are often completely at odds with traditional liberal values, certainly give them a run for their money when it comes to intolerance of any views other than their own.

Am I anxious? Not the right word. It’s hard to describe how I feel. The colossal stupidity that marks the world’s march towards conflict and suffering is annoying, but I have a lot less to worry about than most folks. I have no children whose future might concern me. I am in my early 60s, which means that the majority of my lifespan is behind me already, and it was a good life so far. I have no complaints. And there is nothing I can do to help avoid the outcome that I fear. An old joke pops into my mind, one I heard as a child in Hungary, about the railroad watchman who is taking an exam. He is asked what he would do if he saw two express trains heading towards each other on the open track. “I’d call the wife out from the shack,” he says, “because there’s nothing else that I can do and I’m sure she’s never seen a crash quite as big as this one!”

“The lamps are going out all over Europe,” declared Sir Edward Grey in London early August 1914, as the country that he served as foreign secretary was about to declare war on Imperial Germany. The lamps may soon start to go out all over the world. So here I am, telling my beautiful wife that we can watch the show together. My only regret is that we don’t have a ladder long enough to reach the rather tall roof of our townhouse condo. If I did, we’d have a prime view of downtown Ottawa for when the mushroom clouds blossom over its skyline.

 Posted by at 1:16 pm
Jan 132024
 

In 1981-82, I served as a conscript in what was then called the Hungarian People’s Army.

As an engineering student, I was trained as a radar operator, which is several notches above cannon fodder I suppose. Still, I do not have fond memories of the time.

Nonetheless, I have to admit that there were some educational moments.

Having once lived in a resort hotel that my stepfather was managing, in the spectacular, historic small town of Visegrád at the bend of the Danube, I learned how a commercial-grade kitchen, serving 100+ people, operates. Standards in Hungary were quite strict at the time, and managing such a kitchen entailed both enforcing food safety and hygiene standards and tasks such as managing and recycling meal samples, which would be used by health authorities in case of a suspected case of food-borne illness.

The military base where I spent most of my time as a conscript was an active air defense installation, part of the country’s peacetime air defense network. Nonetheless, they had a chronic shortage of officers, which meant that many tasks that would normally have been assigned to commissioned or non-commissioned officers were instead handed to us conscripts. Once they learned that I had some knowledge of how a kitchen is run, I was frequently assigned kitchen duty: No, not washing dishes (though I did that, too, in the early months of my service) but as kitchen supervisor, responsible for everything including obtaining the needed ingredients from our food storage (run by a civilian employee) and taking samples. It was a surprisingly educational experience.

Or how about the time when I was tasked with ordering… a freight train? Not just any train, mind you, but a specialized train (and route) to carry oversize equipment (our large Ural trucks that carried radar equipment and electronics) with a larger-than-standard cross-section to the USSR border, to participate in some international war games exercise. Fortunately, I didn’t have to go myself, my participation was limited to a journey to the regional headquarters of Hungary’s national railway company, where I had to patiently, and correctly, explain to the person responsible what kind of train we needed and why.

I also did minor tasks such as keeping the base’s one and only television set (an aging color set, a Videoton Color Star television, a mostly Soviet design I was told) alive. I was also responsible for the base’s movie projector, and I took weekly trips to Budapest to get a fresh movie on film, for movie night Mondays (back in the early 1980s, there was no television broadcast in Hungary on Mondays.)

The base where I served no longer exists. First, the military abandoned it. The municipality that inherited it tried to sell without much success, even as the facility was stripped, e.g., of nearly all metal bits by (I presume) metal thieves. Someone took a walk around the base in the early 2000s and put the resulting video on YouTube; it looked almost like parts of the city of Pripyat, near Chernobyl, except that in this case, I was looking at a building that I remembered very well personally, having spent some nine months of my life there.

In the end, the entire facility was demolished, to make way for a solar energy farm, if memory serves me correctly.

All that is to say that I was quite surprised, pleasantly I might add, when I discovered the other day that back in 2022, the local municipality decided to install a small memorial plaque thanking all those who served there in defense of Hungary’s airspace. The cynic in me was wondering if there was any profit in this act (it was, after all, partially financed by the EU, it says so on the plaque itself) even as I actually felt a bit of gratitude that our service was not completely unnoticed after all.

What can I say? The plaque is actually quite nice. I might even visit the spot some day.

 Posted by at 4:34 pm
Jan 102024
 

Here are the first few lines of a program I wrote over 40 years ago, an early attempt to model a massively parallel processor architecture.

No, the program is nothing special. And there are much better ways to create practical multiprocessor/multicore systems. The reason why I copy-pasted this image here has to do with something else: the fact that it was written in the Pascal programming language.

Pascal was just one of the many creations of one of the giants of computer science, Niklaus Wirth.

I learned yesterday that Wirth, who was born back in 1934, passed away on January 1.

 Posted by at 10:31 pm
Jan 042024
 

Looking at this image by Kyodo News showing the wreck of that Airbus 350 that burnt to a cinder at Haneda Airport the other day, I continue to feel astonished that not only did everyone survive, most of the almost 400 passengers were not even injured!

Photo taken from a Kyodo News helicopter on Jan. 3, 2024, shows a Japan Airlines plane a day after it caught fire on a runway at Haneda airport in Tokyo following a collision with a Japan Coast Guard aircraft while landing. (Kyodo)

It really boggles the mind. I hope that the JAL flight crew who facilitated what, for all intents and purposes, was a textbook successful evacuation from a severely damaged, burning aircraft, will get the recognition they deserve.

Although unwelcome, it was also a good test of the A350 airframe and its ability to protect passengers long enough for a successful evacuation.

 Posted by at 1:08 am
Dec 242023
 

At this time of the year, especially in these tumultuous times, is there anything else I could possibly wish for?

Earthrise from Apollo 8

And from the crew of Apollo 8, we close with good night, good luck, a merry Christmas, and God bless all of you — all of you on the good Earth.

 Posted by at 2:34 am
Dec 242023
 

I don’t think I’ve ever done a “year in review” bragfest thing in my blog, but this year has been… well, surprisingly productive, helped in part by our AI friends.

Here are some of the things I created this year:

  1. A science-centered front-end for the major large language models, with support for LaTeX, markup, SVG graphics generated by the AI, and good quality PDF output. Also, savable conversations and compatibility with several Anthropic and OpenAI models. I am quite proud of this, not to mention that it has since become my primary means of accessing LLMs. (I even thought about commercializing it, but I fear it’s way too much hassle and in the end, without proper marketing, just not worth the effort.)
  2. A Web-based application to model image recovery of a rotating exoplanet with varying illumination, viewed through the solar gravitational lens.
  3. A Web-based application to model a constellation of four satellites, used in a precision gravitational experiment to detect the presence of a specific type of deviation from Newtonian gravity.
  4. A Web-based application to model imaging by multiple gravitational lenses.
  5. Another Web-based application to process and analyze emergency room medical data using machine learning.
  6. A custom telnet implementation to finally make it possible to access my game sites, british-legends.com and mud2.com, from within the browser but without third-party plugins.
  7. A reimplementation of my “seas of Mars” Web applet, written originally in Java, showing what Mars would look like if it was flooded with an ocean.
  8. A reimplementation of code I wrote many years ago, constructing a psychrometric chart and calculator, running in a Web browser.

I also published a number of papers, both on my own and with coauthors:

  1. A paper with Slava Turyshev in Phys. Rev. D, on imaging with the realistic solar gravitational lens (SGL), accounting for its deviation from perfect spherical symmetry
  2. Another paper with Slava in Phys. Rev. D, on the spherical harmonic representation of gravitational lenses
  3. A paper with several (mostly NASA) authors in Planetary and Space Sciences, on the use of solar sailing smallsats for projects, including the SGL
  4. A paper with Slava in Monthly Notices of the Royal Astronomical Society, related to the software I described above about imaging a rotating planet with varying illumination
  5. Another paper in MNRAS, this one with John Moffat, on applying his Scalar-Tensor-Vector Gravity to the case of a difficult galaxy, NGC-1277
  6. Yet another paper in MNRAS under my own name, on recovering our key results on the SGL using strictly geometric optics
  7. Finally, another sole-author paper of mine, published in Astrophysics and Space Science, also related to the corresponding software, about using a satellite constellation for gravitational anomaly detection.

Additionally, I completed several in-house projects, including a much dreaded major Joomla! upgrade: Joomla! is the content management system I use for several of my Web sites, and the upgrade required first upgrading PHP, which in turn required fixes to countless instances of PHP code I wrote as many as 20 years ago, code that is not compatible with modern PHP versions. In the process, I also wrote replacement alternatives to two no longer supported third-party Joomla! components, to view images as thumbnails, and to view an image slideshow.

I also completed the Google foobar challenge, Google’s secret recruiting tool. No, I am not looking for a job at Google, but the challenge was, well, challenging (in a fun way) and it also allowed me to learn Python, the language I chose to implement the code that the challenge required. So now I know Python. Not a Python expert by any means, but I feel confident in my ability to use that language (which, incidentally, turns out to be more fun than I anticipated.)

So not quite an annus mirabilis (I don’t expect to discover a new relativity theory anytime soon) but not a bad year. And at least for a small part of this work, I even got paid. Not much, mind you, but I’ve been able to pay our bills so I am not complaining. I suppose if I were smarter, I’d do more work for money, but then again, there’s the quality of life thing, too…

 Posted by at 2:27 am
Dec 142023
 

I wanted to check something on IMDB. I looked up the film. I was confronted by an unfamiliar user interface. Now unfamiliar is okay, but the UI I saw is badly organized, key information (e.g., year of release, country of origin) difficult to find, with oversized images at the expense of useful content. And no, I don’t mean the ads; I am comfortable with relevant, respectful ads. It’s the fact that a lot less information is presented, taking up a lot more space.

Fortunately, in the case of IMDB I was able to restore a much more useful design by logging in to my IMDB account, going to account settings, and making sure that the Contributors checkbox was checked. Phew. So much more (SO MUCH MORE) readable, digestible at a glance. Yes, it’s smaller print. Of course. But the information is much better organized, the appearance is more consistent (no widely different font sizes) and the page is dominated by information, not entertainment in the form of images.

IMDB is not the only example. Recently, after I gave it a valiant try, I purposefully downgraded my favorite Android e-mail software as its new user interface was such a letdown. At least I had the foresight to save the APK of the old version, so I was able to install it and then make sure in the Play Store settings that it would not be upgraded. Not that I am comfortable not upgrading software but in this case, it was worth the risk.

All this reminds me of a recent discussion with a friend who works as a software professional himself: he is fed up to his eyeballs with the pervasive “Agile” fad at his workplace, with its mandatory “Scrum” meetings and whatnot. Oh, the blessings of being an independent developer: I could tell him that if a client mentioned “Agile” more than once, it’d be time for me to “Scrum” the hell out of there…

OK, I hope it’s not just grumpy ole’ complaining on my part. But seriously, these trendy fads are not helping. Software becomes less useful. Project management culture reinvents the wheel (I have an almost 50-year old Hungarian-language book on my shelf on project management that discusses iterative management in depth) with buzzwords that no doubt bring shady consultants a lot more money than I ever made actually building things. (Not complaining. I purposefully abandoned that direction in my life 30 years ago when I quietly walked out of a meeting, not having the stomach anymore to wear a $1000 suit and nod wisely while listening to eloquent BS.) The result is all too often a badly managed project, with a management culture that is no less rigid than the old culture (no fads can overcome management incompetence) but with less documentation, less control, less consistent system behavior, more undocumented dependencies, and compromised security. UI design has fads that change with the seasons, united only by results that are about as practical as a Paris fashion designer’s latest collection of “work attire”.

OK, I would be lying if I said that only bad things come out of change. Now that I use AI in software development, not a day goes by without the AI teaching me something I did not know, including tools, language features and whatnot that can help improve the user experience. But it would be so nice if we didn’t take three steps back for every four steps forward.

 Posted by at 10:21 am
Dec 112023
 

A welcome sight: A seemingly civilized discussion between Volodymyr Zelenskyy and Viktor Orban.

Of course “frank” in the language of diplomacy can mean many things, but if their posture is any indication, the conversation might have been mutually respectful, perhaps even productive. Moments like this have been known in the past to break the ice where more formal encounters led nowhere. One can only hope…

 Posted by at 11:11 am
Dec 092023
 

I am looking at the summary by Reuters of the European Union’s proposed regulatory framework for AI.

I dreaded this: incompetent politicians, populist opportunists, meddling in things that they themselves don’t fully understand, regulating things that need no regulation while not paying attention to the real threats.

Perhaps I was wrong.

Of course, as always, the process moves at a snail’s pace. By the time the new regulations are expected to come into force, 2026, the framework will likely be hopelessly obsolete.

Still: Light transparency requirements as a general principle, severe restrictions on the use of AI for law enforcement and surveillance, strict regulation for high-risk systems… I am compelled to admit, the attitude this reflects makes a surprising amount of good sense.

Almost as if the framework was crafted by an AI…

 Posted by at 11:57 am
Dec 072023
 

Today, December 7, marks the 82nd anniversary of the attack on Pearl Harbor.

Discussion of the Pacific War inevitably leads to discussion of the morality and necessity of the atomic bombings of Hiroshima and Nagasaki.

I have long argued, and continue to argue, that it was the only acceptable decision for Harry Truman to make back during the fateful summer of 1945. And I just came across an unusual data point that supports my argument: the manufacture of Purple Hearts.

Wikipedia tells us that the Purple Heart is a US military decoration awarded to those wounded or killed while serving. Needless to say, Purple Hearts must have been in high demand during the war years, between 1941-1945. The decorations obviously need to be manufactured, and that means the US government placing an order for them in anticipation of casualties during any conflict.

And it was an order of stunning magnitude that they placed in 1944-1945, anticipating the invasion of Japan: Something like half a million Purple Hearts were stockpiled. As a result of this and other unused stocks, it was not until the year 2000 that the US government ordered a new supply, and the old supply, though running low, remains in existence to this date.

So imagine that you are the newly minted president of the United States, after your former boss, Roosevelt, dies. You are informed that your government just completed an astonishing effort to create an immensely powerful new weapon, and it is ready for deployment. You are facing a ruthless enemy: Let’s not forget that the Empire of Japan was no less genocidal than Hitler’s regime, perhaps in some ways even more so (look up Unit 731 on Wikipedia if you have the stomach for it.) Perhaps they are ready to surrender. Perhaps not. But until they are, they remain the enemy. You don’t have the benefit of hindsight. You know what you know and it’s July 1945.

How could you NOT order tactical deployment of the new weapon? As opposed to keeping it in reserve or worse yet, wasting one for a theatrical “demonstration”? Wouldn’t that be an open betrayal of the American servicemen fighting in the Pacific theater? An almost treasonous act?

Yes, there were dissenting voices. But, lest we forget, the conventional bombing campaigns were just as brutal on the civilian population as the nuclear bombs, perhaps even more so. The firebombings of Dresden and Tokyo serve as splendid examples of just what the Allied powers were able and willing to do to enemy cities and their civilian population. Of course there was dissent. Americans are not without conscience, and senior political and military leaders in 1945 were no exception. But it was not until the 1960s that questioning the morality of the use of these weapons became… fashionable.

Yet here we are, more than 78 years later, and not a single nuclear weapon was used in anger ever since. That’s not an iron clad guarantee of course, but at least a ray of hope. Perhaps Hiroshima and Nagasaki achieved more than help bring an end to the War in the Pacific. Perhaps they also helped shape our public perception of nuclear war as the pinnacle of abhorrence.

In the meantime, though, if anyone wonders about the morality of Truman’s decision, perhaps it’s a good idea to contemplate the half million (give or take) surplus Purple Hearts.

 Posted by at 9:41 pm
Dec 062023
 

A few days ago, I came across an article that described a remarkable paper, published in the USSR more than 50 years ago, with predictions on climate change.

Predictions that proved remarkably prescient.

I first read about Mikhail Budyko’s article in a recent review, published on EOS three years ago. What caught my attention, in particular, was Fig. 1 of that article, reproduced below, that shows just how spot on Budyko’s predictions happen to be.

Budyko’s 1972 predictions (solid gray lines) of a) surface temperature and b) changes in Arctic sea ice, compared to observational data from NASA Goddard and IPCC predictions.

Naturally, I wanted to see the original reference, which proved harder than I expected. While it was cited many times, the paper was almost impossible to find. Although I did locate it in an online Russian library, it was only an index entry, with the (unscanned) copy available only for reading in person.

But then… Fortunate favors the… foolish? Persistent? I stumbled upon a 2020 Russian-language publication containing full reprints of several papers by Mikhail Budyko, including the paper in question.

I took it upon myself then to translate the paper in its entirety, with help from one of our AI friends. (AI can do a remarkable job translating technically challenging content, much better than dedicated translation software, albeit some supervision is required.)

Yes, Budyko indeed accurately predicted human-induced climate change. His concerns about rapid changes, “tipping points” are also well-justified. Notably, his work was written before climate change became political football. It’s the work of an excellent climate scientist, not a political hack.

 Posted by at 11:57 pm
Dec 052023
 

Now that Roy Kerr’s paper on black holes and singularities is on arXiv, I am sure I’ll be asked about it again, just as I have been asked about it already on Quora.

Roy Kerr, of course, is one of the living legends of relativity theory. His axisymmetric solution, published in the year of my birth, was the first new solution in nearly half a century after Karl Schwarzschild published his famous solution for a spherically symmetric, static, vacuum spacetime. I hesitate to be critical of this manuscript since chances are that Kerr is right and I am wrong.

Kerr now argues that the singularity theorems are nonsense, and that his axisymmetric solution actually hides some nonsingular configuration of matter therein.

At a first glance, the paper seems well written and robust. Still… when I dug into it, there are a few things that caught my attention, and not in a right way. First, the paper takes argument with “singularity believers” using language that almost sounds like pseudoscience. Second, it has some weird factual errors. E.g., it asserts that black holes “as large as 100 billion solar masses have been observed by the James Webb Telescope” (not even close). Or, it describes the famous Oppenheimer-Snyder paper of 1939 as having “used linear, nineteenth century ideas on how matter behaves under extreme pressures” (actually, Oppenheimer and Snyder discuss the collapse of a “dust” solution with negligible pressure using the tools of general relativity with rigor). Kerr further criticizes the Oppenheimer-Snyder paper as attempting “to ‘prove’ that the ensuing metric is still singular”, even though that paper says nothing about the metric’s singularity, only that the collapsing star will eventually reach its “gravitational radius” (i.e., the Schwarzschild radius). Nonetheless, later Kerr doubles down by writing that “Oppenheimer and Snyder proved that the metric collapses to a point,” whereas the closest the actual Oppenheimer-Snyder paper comes to this is describing collapsing stars as stars “which cannot end in a stable stationary state”.

Never mind, let’s ignore these issues as they may not be relevant to Kerr’s argument after all. His main argument is basically that Penrose and Hawking deduced the necessary presence of singularities from the existence of light rays of finite affine length; i.e., light rays that, in some sense, terminate (presumably at the singularity). Kerr says that no, the ring singularity inside a Kerr black hole, for instance, may just be an idealized substitute for a rotating neutron star.

Now Kerr has an interesting point here. Take the Schwarzschild metric. It is a vacuum solution of general relativity, but it also accurately describes the gravitational field outside any static, spherically symmetric distribution of matter in the vacuum. So a Schwarzschild solution does not imply an event horizon or a singularity: they can be replaced by an extended, gravitating body that has no singularities whatsoever so long as the radius of the body is greater than the Schwarzschild radius associated with its mass. The gravitational field of the Earth is also well described by Schwarzschild outside the Earth. So in my reading, the crucial question Kerr raises is this: Is it possible that once we introduce matter inside the event horizon of a Kerr black hole, perhaps that can eliminate the interior Cauchy horizon or, at the very least, the ring singularity that it hides?

I don’t think that is the case, and here is why. Between the two horizons of a Kerr black hole, the “radial” coordinate is now the timelike coordinate, with the future pointing “inward”, i.e., towards the Cauchy horizon. That means that particles of matter do not have trajectories that would allow them to avoid the Cauchy horizon; no matter what path they follow, they will reach that horizon in finite proper time.

Inside the Cauchy horizon, anything goes, since closed timelike curves exist. So presumably, it might even be possible for particles of matter to travel back and forth between the past and the future, never hitting the ring singularity. But that’s not what Kerr is suggesting in his paper; he’s not talking about acausal worldlines inside the Cauchy horizon, but some “nonsingular interior star”. I don’t see how to make sense of that suggestion, because I don’t see how a stationary configuration of matter could exist inside the inner horizon. Wobbling back-and-forth between yesterday and tomorrow in a closed timelike loop is not a stationary configuration!

For these reasons, even as I am painfully aware that I am arguing with a Roy Kerr so there’s a darn good chance that he’s right and I’m spouting nonsense, I must say that I remain unconvinced by his paper. The language he uses (e.g., describing the business of singularities as “dogma”) is not helping either. Also, his description of the interior of the rotating black hole sounds a bit off; to use his own words, “nineteenth century” reasoning, much more so than the Oppenheimer-Snyder paper that he criticizes.

 Posted by at 7:31 pm
Dec 022023
 

I just came across a quote attributed to Einstein: “If I had foreseen Hiroshima and Nagasaki, I would have torn up my formula in 1905.

The problem with this quote is that it is utter nonsense, and not something Einstein likely would have said, ever.

An image of Einstein that is just as real as some of the quotes attributed to him. Courtesy of Midjourney.

The “formula” of mass-energy equivalence simply states that an object’s resistance to motion (its inertia) is proportional to its energy-content. That is all. Yes, I know that in the popular imagination, \(E=mc^2\) is frequently associated with the nuclear age. But that’s nonsense. \(E=mc^2\) is not about “converting” anything into anything. Mass-energy is mass-energy, and it is conserved. Whether it is in the form of the nuclear binding energy of a uranium atom (or for that matter, the chemical binding energy of carbon atoms in a fireplace log) or in the form of the kinetic energy of photons released by a nuclear or chemical reaction has absolutely nothing to do with \(E=mc^2\): the formula does not explain nuclear fission any more than it explains the chemical reactions that govern the burning of wood.

But then, what about this quote, which appears in a number of reliable places, including Wikiquotes?

It is attributed to a book published by a William Hermanns, who supposedly interviewed Einstein on a number of occasions between the late 1920s and Einstein’s death in 1955.

The person appears real. I found, in Google’s archive, the May 2, 1955 issue of Life, which includes a personal recollection of one of Life’s own editors, William Miller, of his very last visit to Einstein, when he actually met William Hermanns.

Hermanns’s book, Einstein and the Poet: In Search of the Cosmic Man, is also real: In fact, it even has a Kindle edition.

But… how much of it is true?

Considering that Hermanns has an exceptional biography (which one can read on a Web site dedicated to his life) it is more than a bit odd that the only references to his name in Wikipedia are Einstein-related. Yet his name does not appear in notable Einstein biographies, including Abraham Pais’s definitive scientific biography, or Walter Isaacson’s exceptionally good Einstein bio.

When I read the few pages of Hermanns’s book that are available as a Kindle preview, I grow even more suspicious. For instance, according to Hermanns, already in 1927 Einstein was “marked by Nazis as ‘Enemy number One of the Nation,’ and the object of at least seven plots to take his life.” News to me.

But then, Hermanns goes on to quote Einstein who supposedly said, “When I was about five, my father gave me a compass as a toy. I wanted to find out why the needle never deviated […] When I asked my uncle, an engineer, he immediately proceeded to teach me some fundamentals of algebra, with this advice: ‘What you don’t know, call x, then hunt til you find what it is.’ From that time on, I have called everything I didn’t know x, especially magnetism.

As I asked ChatGPT just moments ago, can you imagine Einstein saying these words, in 1927, to a stranger who just visited him?

Long story short, I don’t know what to think. Based on what I have read, I do not believe Hermanns’s accounts of his conversations with Einstein are credible. At the very least, they must be severely distorted versions of Einstein’s words, probably deeply colored, warped by Hermanns’s imagination. For what it’s worth, ChatGPT concurs: “The lack of independent verification and recognition in authoritative sources casts doubt on the accuracy and credibility of his accounts. Your reservations about accepting Hermanns’ narratives as factual are well-founded.”

 Posted by at 11:32 pm
Dec 012023
 

Well, here it is, a local copy of a portable large language and visual model. An everywhere-run executable in a mere 4 GB. Here’s my first test, with a few random questions and an image (one of my favorite Kliban cartoons) to analyze:

Now 4.57 tokens per second is not exactly fast but hey, it runs on my 7-year old workstation, with no GPU acceleration, and yet, its performance is more than decent.

How is this LLM different from GPT or Claude? Well, it requires no subscription, no Internet connection. It is entirely self-contained, and fast enough to run on run-of-the-mill PC hardware.

 Posted by at 12:12 am
Nov 302023
 

I made some mistakes in the past. I never made a half-a-billion dollar mistake.

Neither did Chris Lewicki, but he came awfully close.

I just read this delightful account of how Lewicki almost fried the innards of the Spirit rover, destined for Mars, during an engineering test that took place just weeks before the rover was launched.

I can only imagine the sinking feeling in his stomach he must have felt when he thought that the rover was ruined. My mistakes never came close in value, but the sensation is uncomfortably familiar.

Fortunately, in his case, the disaster never actually materialized. In simple terms, yes, he plugged a cord into the wrong outlet, but fortunately, the other end of the cord was not plugged in.

To this day, Lewicki must feel like one of the luckiest persons on the planet.

The illustration is from his blog post, but its appearance suggests that it might have been produced by DALL-E. Or maybe Midjourney or Stable Diffusion? The style looks very reminiscent of AI-produced cartoon images.

 Posted by at 6:17 pm