Nov 202023

I am not Jewish. My family is not Jewish.

My father’s first wife, however, was Jewish. His son from that first marriage, born decades before I was born, is Jewish and married a Jewish woman. My mother’s grandparents, though not Jewish, worked for a Jewish family at the turn of the last century, and lived in their household.

That might explain how it came to be that I grew up using expressions like “gott sei dank” or “na zag schon”, much to the amusement of some of my Jewish friends who know less Yiddish than I. Or why I have friends who had parents, siblings, aunts, nieces, spouses murdered in Auschwitz or shot into the Danube by the Hungarian Arrow Cross during the Holocaust.

No, that does not mean that suddenly I have a favorable opinion of Mr. Netanyahu (I don’t) or that I turn a blind eye when I see innocents suffer. I have criticized and will again criticize the government of Israel. In fact, for what it’s worth, I think Netanyahu is a crook, his pact with the far right is a poison pill for Israeli democracy, and that the outsize influence of the ultraorthodox is corrupting Israeli politics. Unfortunately I also do not see a long-term solution, an achievable goal: None of the foreseeable alternatives provide an acceptable outcome: The two-state solution undermines Israeli security, annexation would create an Arab-majority state, more drastic “solutions” like wholesale expulsion or genocide (of either Palestinians or Jews) are obviously unacceptable. So the status quo remains by default, even though it’s not exactly a solution either.

But “never again” must mean something. Failure to respond to the attack on October 6 would amount to the Israeli state abandoning its most basic responsibility to its citizens. It is the sad nature of war that when one party hides behind its civilians, civilians suffer. Notably, however, hiding behind civilians only works against a civilized opponent that abhors “collateral damage”: if Israel was as savage, as hell-bent on genocide as its enemies suggest, hiding behind civilians would not work as a Hamas tactic.

Earlier, I came across a meme that depicted a female Arab member of Israel’s Knesset, enumerating the rights she enjoys as a full citizen of Israel. I changed my mind about reusing that meme since I suspect that it was created without her approval. Even though she is a public figure, so using her image in this manner is arguably legitimate, it felt a bit tasteless.

Instead, let me just repost a propaganda meme straight from Israel’s defense forces.

It’s not even new; it dates back to 2014. And yes, it’s a propaganda piece. But like all good propaganda, it is based on the sad truth.

 Posted by at 1:01 pm
Nov 082023

Sometimes it feels… so pretentious.

Here I am, saying all sorts of clever things in my blog. I once declared blogs to be write-only media, my way of shouting at the world without the world saying anything in return, but that kind of ceased being true when I decided, eons ago, to share my blog posts on social media, where a few friends at least reacted occasionally.

So who do I think I am, proclaiming my wisdom to the world, really?

For instance, a few days ago I thought I’d blog about the first precision clock arriving in America centuries ago, and promptly failing, leading to a better understanding of how the gravitational acceleration on the surface of the Earth may change with geographic location. But is there anything I can add to the subject other than what’s in the article I am citing?

Or take this report from earlier today, about Singapore’s Prime Minister expressing very much the same concerns that I have about the world experiencing a moment of danger not unlike the moments before the Great War. OK, so I blog about it. Is there anything I can add other than, hey, look, I am ever so clever, even Singapore’s PM shares my views!?

I suppose I feel most comfortable blogging about my actual research or my work. These are subjects that I can address with some competence.

Or maybe just blog about cats. They know how to be wise and silent, after all.

Meanwhile, in the world of humans…

F-15s strike weapons facility in Syria

By Lauren C. Williams and Jennifer Hlad

ABOARD A MILITARY PLANE—Two U.S. F-15 fighter jets attacked a weapons storage facility in eastern Syria on Wednesday, in what Defense Secretary Lloyd Austin called a “precision self-defense strike” in response “to a series of attacks against U.S. personnel in Iraq and Syria by the [Iranian Islamic Revolutionary Guard Corps]-Quds Force” and related groups.

So I must now follow my cats’ example and resist the urge to blog about how the US and Iran might already be at war…

 Posted by at 9:51 pm
Nov 042023

I grew up on The Beatles.

OK, I came a little late I guess, as The Beatles broke up when I was in the second grade, and truly it wasn’t until the fifth grade that a classmate introduced me to the Red and Blue albums… But I fell in love with their music. I couldn’t believe that they were not together anymore, and like many young teens my age, I kept hoping that they’d reunite until Lennon was murdered.

I never stopped loving their songs.

What I did not expect was that I’d be listening to a new Beatles song almost 50 years later, in 2023.

I admit I was skeptical at first. I expected something that would bear a vague, soulless resemblance to what The Beatles used to be, a cheap attempt to cash in on their fame one very last time.

Instead, I was listening to an authentic Beatles song. One of their best, as a matter of fact. And I was looking at a video that brought Lennon and Harrison back to life, cheerful, funny, joyous, happy…

Bless Peter Jackson. There are “deepfakes” and then there are “deepfakes”… and I cannot think of a more appropriate, more respectful use of AI, bringing legends of the past back to life, as in this video.

I have listened to the song and watched Peter Jackson’s masterful creation at least five times in a row. And every time, I was almost in tears.

 Posted by at 6:53 pm
Nov 012023

A few minutes ago, I checked Google News on my phone and lo and behold, there was a link to Universe Today, a new article discussing my latest manuscript on multiple gravitational lenses.

I knew that this was in the works, as the author approached me with some questions earlier in the day, but I didn’t expect it to appear this quickly, and, well, seeing it on my phone like this was a nice surprise.

Had the author asked, I’d have happily granted permission to use one of my generated images or animations involving multiple lenses.

Meanwhile, my paper on a four-satellite configuration used to detect deviations from Newtonian gravity was published by Astrophysics and Space Science, one of the Nature journals. I am officially permitted (in fact, encouraged) by Springer to share the link to an online read-only version of the published paper.

 Posted by at 1:25 am
Oct 292023

Every so often, a Google Calendar reminder that I set up ages ago reminds me to charge our old cell phones. This is to prevent their batteries from dying as a result of a deep discharge.

Old cell phones, you ask? Well, yes. When we swapped phones, we kept the old ones for a while, just in case. And then we kept them because wiping them securely seemed like too much of a hassle. And then we kept them because, well, what’s the alternative? Landfill? Yes, I know, some service providers accept old phones, might even give you credit. But what happens to those old phones? Who needs them? Who can use them, with their ailing batteries and, worst of all, the absence of software updates, including security patches?

Indeed, this end of support was the main reason why we ditched phones in the past. And it really is tragic. Never mind phones old enough to have outdated specs. I have here a few devices that have hardware specs that would be reasonable on the low end even today. The devices are perfectly functional. Yet they are worthless.

This is just… conspicuous consumption, forced upon us by a society that measures the health of the economy not by its stability or sustainability but by growth. Pointless, limitless growth.

Never mind that in the meantime, the middle class shrinks, the income and wealth gap widens, society is becoming more polarized, ultimately threatening the very foundations of our Western liberal democracies. Who cares about such nonsense when there’s a new phone out there with half a dozen camera lenses and who knows what other nonsense just to make you believe that they’re worth your money and that it’s perfectly okay to throw away a capable, quality piece of electronics that would have many more years of useful life left?

Darnit, I realize I almost sound like a grumpy old commie, when in reality what I worry about is the future of a healthy capitalist society, characterized by freedom of conscience, the rule of law, freedom of speech, and freedom of enterprise. But there’s a fine line between freedom of enterprise and the “tragedy of the commons”, and when free enterprise undermines the very foundations of liberal democracy, perhaps it is advisable to do something about it before it is too late.

By the way, I really liked these Nokias. What a pity we had to get rid of them. They still function perfectly, but without security patches, they’re not worth the risk.

 Posted by at 2:58 pm
Oct 192023

Last night, I received notification from the CRA about an upcoming small tax refund.

When I logged on with my business account, it appeared to show that I had 3 unread messages, though there was a funny smudge before the ‘3’ in the notification icon.

When I clicked, I saw only one unread message. When I went back to the main screen, I now saw a ‘4’. That’s when I realized that the smudge was… a minus sign.

Indeed I had four messages shown in the mail interface, all read. So instead of counting the number of unread messages as a positive number, the UI showed the number of read messages as a negative number.

I have not yet received the refund. I hope that when (if?) it shows up in my bank account, it will have the correct sign.

 Posted by at 10:15 pm
Oct 122023

I’m doing more work on gravitational lensing. In particular, the little ray tracing model that I developed can now use actual astronomical images as sources. Here’s a projection of a nice spiral galaxy as it would be seen through a pair of non-coplanar, imperfectly lined up lenses:

Somehow, I suspect, no astronomer would recognize (at least not without a spectral analysis) that these are four images of the same rather nice-looking galaxy, NGC-4414:

These lensing examples also demonstrate how difficult it is to reconstruct either the original view, or the mass distribution of the lens itself, when all we see is something like the first image above.

 Posted by at 9:35 pm
Sep 162023

My friend John Moffat has a finite quantum field theory that, I think, deserves more attention than it gets.

The theory is nonlocal (then again, so is quantum physics to begin with). However, it does not violate causality. So its nonlocality is a mathematical curiosity, not a physical impossibility.

The essence of the theory is present in the form of its “nonlocal field operator”. Given, e.g., a scalar field in the form \(\phi(x),\) the field is transformed as

$$\tilde\phi(x)=\int d^4x’f(x-x’)\phi(x’).$$

Now if we just used the Dirac delta-function \(f(x-x’)=\delta^4(x-x’),\) we’d get back \(\phi(x).\) But what if we use some other function, the only restriction being that \(f(x)\) must be an entire function, which is to say, unambiguously defined without poles or singularities over the entire complex plane?

Well, then, assuming again that \(f(x)\) is an entire function, we can integrate iteratively in parts, until we arrive at an expression in the form,

$$\tilde\phi(x)={\cal F}(\partial_x)\phi(x),$$

where \({\cal F}(\partial_x)\) is a derivative operator, typically some power series in the form \(\lambda_i\partial_x^i\), acting on \(\phi(x).\)

Why is this good for us? Because this field redefinition can suppress high-energy divergences in the theory, essentially doing away with the need for renormalization, which, of course, is a Big Claim indeed but I think John’s theory works.

John’s first substantive papers on this topic were titled Finite quantum field theory based on superspin fields (J. W. Moffat, Phys. Rev. D 39, 12 (1989)) and Finite nonlocal gauge field theory (J. W. Moffat, Phys. Rev. D 41, 4 (1990)). Unfortunately these papers predate so only the paywalled versions are available. They are beautiful papers that deserve more recognition. More recently, John wrote another paper on the subject, collaborating with a student. One of these days, I’m hoping to spend some time myself working a bit on John’s theory because I believe it has merit: The theory appears to remain causal despite the nonlocal operator, and by doing away with the need for renormalization, it makes canonical quantization almost trivially possible. I keep wondering if there is, perhaps, a catch after all, but if that’s the case, I have yet to find it.

 Posted by at 1:37 pm
Sep 122023

Yes, that’s me. At least according to The Political Compass.

It does not surprise me much, mind you. While I am not a wild-eyed, “woke”, progressive “social justice warrior” (in fact, I am increasingly a deeply fed up with the “woke” lot), many of my views tend to align broadly with the traditional left. I also reject authoritarianism in all forms, and while I don’t endorse unconstrained freedom (e.g., in the economy), I largely view constraints as a necessary evil, not as a universal solution.

And, of course, I absolutely, strongly, vehemently reject any and all forms of personality cults.

So here, then, is my question: Given the direction our societies are heading, will there be room for left-wing libertarians like me in the future? Authoritarianism seems to be so much in vogue these days, be it the culture of intolerance in the name of tolerance as practiced by the woke left, or the more traditional authoritarianism of the nationalist right. The common theme that unites them is their rejection of liberal democracy’s core systems of institutions.

To offer an idea of what the four quadrants represent: Left-wing authoritarians (red, upper left) include Stalin and Mao. Joe Biden and Donald Trump both qualify as right-wing authoritarians (blue, upper right) according to the Compass, though I am sure not nearly as extreme as Pinochet or Mussolini, also in the same quadrant. Hegel or Ayn Rand along with von Mises are right-wing libertarians (purple, lower right). The green quadrant (lower left), where I found myself, apparently includes Gandhi, Mandela and Noam Chomsky. Urgh. I so disagree with Chomsky on many things. Oh well, these are big quadrants.

 Posted by at 11:11 pm
Sep 122023

I gave a talk on the Solar Gravitational Lens in Montreal back in July, using the above title.

Video of the talk is now available online, courtesy of the Interstellar Research Group.

I just listened to it myself and I didn’t cringe too much hearing my own voice or watching myself, which is probably a good sign?

 Posted by at 12:31 am
Aug 082023

For the longest time as developers, we were taught not to reinvent the wheel. “There is a library for that,” we were told, so instead of implementing our own solutions for common, recurring tasks, we just imported and linked the library in question.

And sure, it made a lot of sense. Countless hours of development time were saved. Projects were completed on time, within budget. And once the system worked, it, well, worked. So long as there was a need to maintain the software, we just kept the old development tools around for the occasional bug fix and recompile. I remember keeping a Visual Studio 6.0 configuration alive well into the 2010s, to make sure that I could offer support to a long-time customer.

But then… then came the Internet. Which implied several monumental paradigm shifts. One of the most fundamental among them is that a lot of software development no longer targeted cooperating users in a closed environment. Rather, the software was exposed to the public and, well, let’s face it, not all members of the public have the best intentions in mind when they interact with our systems.

Which means that third-party code turned from an asset into a substantial liability. Why? Because of potential security issues. Using old versions of third-party libraries in public-facing systems is an invitation for disaster. Those third-party components must be kept up-to-date. Except…

  • Updating a component may break other things. There is a need for extensive regression testing, especially in complex systems, to ensure that an upgrade does not result in unintended consequences.
  • Updates are not always available. The third-party code may no longer be supported. Source code availability can mitigate this to some extent, but it can still result in a disproportionate level of effort to keep the code secure and functional.
  • Long-term reliance on third-party code implies long-term reliance on the integrity and reliability of the vendor. Code ownership can change, and the new owners may have different objectives. In extreme cases, once reliable third-party code can end up being used as Trojan code in planned cyberattacks.

For a while, there was a great need for third-party code in Web development. HTML4 had limitations, and browser implementations varied wildly. Widely used third-party libraries like jQuery made it possible to prepare code that ran well on all major platforms. But this really is not the case anymore. “Out of the box” HTML5, CSS3 and modern JavaScript are tremendously capable tools and the implementation across major browsers is quite consistent these days, with only minor idiosyncrasies that can be easily dealt with after a modest amount of testing.

So really, my advice these days to anyone developing a new Web application is to avoid third-party libraries when possible. Especially if the application is intended to have a long life-cycle. Third-party code may cut down development time slightly, but the long-term costs may far exceed those savings. And there will still be more than enough to do just to keep up with other changes: witness the changes over time that occurred in browser security models, breaking once functioning Web applications, or the changes between, say, PHP5 and PHP7.

And of course there are still valid, legitimate use cases for specialized third-party libraries. For instance, in a recent project I used both MathJax (for rendering mathematical formulas) and markdown (for rendering displayed code). Developing something like that from scratch is just not an option.

Why am I harping on all this? I am currently facing a minor crisis of sorts (OK, that may be too strong a word) as I am trying to upgrade my Web sites from Joomla 3 to Joomla 4. Serves me right, using a third-party content management system instead of writing my own HTML! Worse yet, I used some once popular extensions with Joomla, extensions that are no longer supported, and which are wholly incompatible with Joomla 4. Dealing with this is difficult and time-consuming.

It would be a lot more time-consuming were it not for the help I get from our LLM AI friends. Thankfully, these tools, GPT-4 in particular, are immensely helpful. E.g., one third-party Joomla extension I used offered a nice way to present images as clickable thumbnails. This extension is now badly broken. However, GPT-4 already helped me write a clean, functional alterative that I’ll be able to use, and thus avoid having to redesign some important pages on my site.

 Posted by at 2:16 am
Aug 072023

The game’s Web site may be dated (hey, it’s a nearly 20 year old template… yes, we’ve been around that long, a lot longer in fact) but it now has a new feature: it is again possible to play MUD1/British Legends from the browser.

The feature is experimental and may still need to be disabled if it glitches but here’s to hoping that it doesn’t.

 Posted by at 2:57 pm
Jul 312023

My high school classmate György (Gyuri) Matavovszky spent the last almost 17 months volunteering for the Red Cross, helping Ukrainian refugees. Without further ado, with his permission, here is an English translation of his latest Facebook post, which sums up his experiences and his personal journey, while also revealing a lot about the sociopolitical environment in which he lives in present-day Hungary.

I shall now take off the Red Cross vest that I first put on 503 days ago and have worn for about 50 night shifts since then. The Hungarian government is closing down the aid point set up at the BOK Hall due to the war, where newly arrived and other homeless refugees from Ukraine could come until now and receive very modest care, minimal food and drinks, hygiene facilities, camp beds with bedding in a communal sleeping area for one, in some exceptional cases two-three nights (since life in Hungary is so good that everyone’s situation surely gets resolved in one-two days, so no one needs to stay longer).

The hall opened for this purpose at the end of March last year. Back then, aid organizations and representatives of various other bodies were moved here from the train station. There was a children’s corner, doctor, pet care, child welfare services, ticket office, mental health support, shuttle buses ran hourly between the train stations and the hall, 1000-2000 people came through here daily back then, who were very easy to provide for initially, as we received huge amounts of donations. The number decreased exponentially, but willingness to donate even faster, so we soon reached the point where rather than abundance, it was need that made things difficult for us. Then everything slowly shifted to a lower gear, for example in November the medical care was also terminated, which I know because I had to accompany a sick person to the Military Hospital, and wait with them from 11pm to 3am for the four hours the Hungarian healthcare system needs to carry out a routine examination. In February, I was a hair’s breadth away from someone dying in front of me. I failed to recognize the signs of a heart attack in a refugee who arrived across the green, or rather blue, border (the Tisza River) – luckily a colleague of mine was more alert and called an ambulance just in time. In the end he survived, now he lives with his family in Győr, has a job too, we know about him.

But this is just one example, because there were many other very difficult situations, too. It wasn’t just the arrivals from Ukraine that were problematic, we Hungarians often didn’t get along easily either, there was tension even among the volunteers at times. Is it okay to give coffee in the middle of the night—this remained an eternally returning question that still has no consensus answer. Because if we give it, they get more lively and won’t let the others sleep, or make more demands of us, too. But if we don’t, we deny them the one joy they may have that day. We too often lost patience, but I won’t focus further on the downsides of our performance. On the very first night I decided that I’m not here to help the refugees, but they are helping me, and I stuck to that pretty much. I accompanied some of them to trains, planes, airport buses, when that was the simplest or most humane way to give directions. In the process, I always developed a connection with them that could no longer be let go of without tears—the worst is when you stand on the platform, hugging them and they hug you too, and you both know you will never see each other again. These moments were always unbearably painful.

The nights had their own arcs—the shift started at 8pm, by midnight we only felt like we were getting into it, by then we were usually tired enough to start feeling a bit numb from it. Somewhere between 2 and 2:30am was the low point, from when the mental state tips over, you start to feel the dawn coming, and this generally calms you down too. The second half of the night was always much easier, and in the morning not only does the sun rise outside, your heart is flooded with light inside too – I always left tired but with great peace in my heart – I will miss this feeling a lot.

Let no one think the BOK Hall is closing because the war is over and there is no more need for it. The war is not over, the BOK Hall would be needed, but the community is poor, I mean there is very little good intention in the budget, we are completely exhausted morally, in character, currently at rock bottom, though I’ve written a lot about this before. There will be something, somewhere instead, but it will be operated by the pro-government Maltese Charity Service, and for sure it won’t be worth even this much. I won’t participate because I’m not Catholic enough and anyway I’m sick of the whole thing. I was sick of it before too, but the Red Cross supervisor kept my spirit up, his name is Gyuri too, we could never decide whether I’m one and he’s the other, or vice versa, I think it’s the latter actually, in my phone he’s saved as Egyik Gyuri (Gyuri One).

I don’t want to be without social work long term, I hope one day I’ll wear a Red Cross vest again, I hope not too long from now. Now I need to pull myself together for mural painting, but if I can get that going maybe I’ll have time for something similar again. I don’t want to be a social worker, but from now on I want something like this always to be part of my life, because meeting unfortunate people results in a fantastically intense wake-up call, and I think in the long run it really helps staying awake. For example, you understand that they often live a much more real, much more honest, much more self-consistent life than us, who collect a pile of assured money every month, which we then spend floating in a beautiful bubble.

There is a lot of cognitive dissonance in the Red Cross too, but still it’s far from the worst organization in the world, its past shines through its present a bit, in my work I managed to meet exemplary people, including some much younger than me who can behave very consciously, very maturely in trying human situations, and in whom I see a lot of potential still. As I look at it, this hidden potential will be needed sooner or later, or rather is needed now, it’s just very hard for the penny to drop, it’s very hard for us to notice this spiritual need.

I won’t beat around the bush, before the war I too spent my days in deep slumber, and I still don’t feel fully awake. However, I very much hope enough bridges have burned behind me that I won’t be able to flee back to where I was living before. In this service ending now, I feel the next personal message from life: Gyuri – one or the other, doesn’t matter – You are mature enough now, You don’t need to do this anymore, because with what you’ve done so far, you’ve detached yourself enough from your previous mode of existence, you’ve gotten from A to B, and even if you don’t see filthy, dirty refugees around you for a couple months, you won’t slide back to where you were before. Yes, I feel this whole thing was an initiation, a tangible step on the path to becoming human, which I desperately needed, and by some miracle this time I didn’t brush it off with some stupid response, as I’ve done countless times before, but this time not. This is what war does!

 Posted by at 3:07 pm
Jul 272023

Don’t look a gift horse in the mouth, they say, so I will not question how, or why, just express my happiness that my frustration is over: Redmine, the software package that I use internally for project management, works again.

It all began with an unpleasant but unavoidable upgrade of the MariaDB database from the ancient version that is part of the CentOS distribution to a more recent one. (Which, in turn, is needed to upgrade my content management software on some of my Web sites.)

Everything worked after this (planned, reasonably well pre-tested) upgrade except for Redmine.

Redmine is beautiful, very useful, but also very frustrating to install and manage. It uses Ruby on Rails, a software environment that… OK, let me not go there. I’ll keep my opinion to myself.

I spent countless hours yesterday, to no avail. The Redmine system refused to start. I installed, reinstalled, configured, reconfigured, uninstalled, reinstalled… Redmine, Ruby, its various management tools, you name it. Nothing did the trick. I gave up long after midnight.

I dreaded the moment today when I’d be resuming that thankless, frustrating exercise with no assured outcome. But I need Redmine. I have too much information in that system that I cannot afford to lose. So eventually I rolled up my sleeves (literally) opened the browser tab that had the link, and hit F5 to refresh the page, expecting the same error message that I’ve seen before to reappear.

Instead… Redmine came up in all its glory, with all my existing project data intact. Everything works.

I was so shocked by surprise I almost felt physically ill. A bit like this Midjourney cat, upon receiving an unexpected, very welcome gift.

Don’t look a gift horse in the mouth they say, so I am not complaining. But I’d still like to know what exactly happened. Why things started to work all of a sudden. I told my beautiful wife to imagine leaving a half-finished knitted sweater in her room one night, only to come back the next morning and finding a beautifully finished sweater there.

My mind, for now, is in a deeply boggled state. I honestly don’t know how or why it happened. But I am a very happy cat tonight.

A footnote: After I wrote the above, late, late, late at night, all of a sudden Redmine failed again, with a different error. I was ready to tear my hair out. But I was able to fix the problem. The likeliest cause as far as I could determine is that although the Redmine site had the correct Ruby version identified, a default setting specified an older, incompatible version of Ruby. It was fortunate that I was able to fix it, otherwise chances are I’d have spent a sleepless night trying.

 Posted by at 7:06 pm
Jun 082023

Glad I am not a politician or public personality as I am about to commit what would amount to political suicide, a’la J. K. Rowling.

The reason? This health warning by The Weather Network, that truly blew my fuse:

Middle line of the red warning at the bottom. That list of folks at high risk:

“[…] older adults, children, pregnant people, and people who work outdoors […]”

Pregnant “people”??? Seriously, why not pregnant primates? Pregnant mammals? Pregnant vertebrates?

Let me not mince words. This is virtue signaling at its worst, pandering to a loud, obnoxious group of “alphabet soup activists”, claiming to, but not really representing gays, lesbians and others who simply just want to live a life in dignity, respected as human beings, enjoying what should really be the inalienable right of every human being on this planet, to be left alone, to be allowed to live a life to the fullest in the company of those they love.

The biggest irony of all? Even as conservatives in many corners of the world, especially here in North America, are busy turning the fictitious country of Gilead from The Handmaid’s Tale into actual reality, what these activists do is no less harmful to women. Their agenda amounts to little more than the idea that “men are better than women at everything, including being women,” as someone recently put it on Quora.

Dear Weather Network, dear Environment Canada (if that’s where the text of the warning came from): Let this serve as a friendly reminder that the English language has a perfectly serviceable word to describe those members of the species homo sapiens who are biologically capable of becoming pregnant: they are called women. Check your dictionaries, it’s there.

 Posted by at 3:09 pm
Jun 052023

I have written before about my fascinating experiments probing the limits of what our AI friends like GPT and Claude can do. I also wrote about my concerns about their impact on society. And, of course, I wrote about how they can serve as invaluable assistants in software development.

But I am becoming dependent on them (there’s no other way to describe it) in so many other ways.

Take just the last half hour or so. I was responding to some e-mails.

  • Reacting to an e-mail in which someone inquired about the physics of supersymmetry, I double-checked with the AI to make sure that I do not grossly misrepresent the basic principles behind a supersymmetric field theory;
  • Responding to a German-language e-mail, after I composed a reply I asked the AI to help clean it up, as my German is rusty, my grammar is atrocious (or maybe not that atrocious, the AI actually complimented me, but then again, the AI can be excessively polite);
  • In a discussion about our condominium’s budget, I quickly asked the AI for Canada’s current year-on-year inflation; with my extension that allows it to access Google, the AI was able to find the answer faster than I would have with a manually executed Google search.

All this took place in the past 30 minutes. And sure, I could have done all of the above without the AI. I have textbooks on supersymmetry. I could have asked Google Translate for a German translation or take my German text, translate it back to English and then back to German again. And I could have done a Google search for the inflation rate myself.

But all of that would have taken longer, and would have been significantly more frustrating than doing what I actually did: ask my somewhat dumb, often naive, but almost all-knowing AI assistant.

The image below is DALL-E’s response to the prompt, “welcome to tomorrow”.

 Posted by at 8:20 pm
May 312023

I just finished uploading the latest release, 5.47.0, of our beautiful Maxima project.

It was a harder battle than I anticipated, lots of little build issues I had to fix before it was ready to go.

Maxima remains one of the three major computer algebra systems. Perhaps a bit (but only a bit!) less elegant-looking than Mathematica, and perhaps a bit (but only a bit!) less capable on some friends (exotic integrals, differential equations) than Maple, yet significantly more capable on other fronts (especially I believe abstract index tensor algebra and calculus), it also has a unique property: it’s free and open source.

It is also one of the oldest pieces of major software that remains in continuous use. Its roots go back to the 1960s. I occasionally edit 50-year old code in its LISP code base.

And it works. I use it every day. It is “finger memory”, my “go to” calculator, and of course there’s that tensor algebra bit.

Maxima also has a beautiful graphical interface, which I admit I don’t use much though. You might say that I am “old school” given my preference for the text UI, but that’s really not it: the main reason is that once you know what you’re doing, the text UI is simply more efficient.

I hope folks will welcome this latest release.

 Posted by at 8:54 pm
May 232023

In the last several years, we worked out most of the details about the Solar Gravitational Lens. How it forms images. How its optical qualities are affected by the inherent spherical aberration of a gravitational lens. How the images are further blurred by deviations of the lens from perfect spherical symmetry. How the solar corona contributes huge amounts of noise and how it can be controlled when the image is reconstructed. How the observing spacecraft would need to be navigated in order to maintain precise positions within the image projected by the SGL.

But one problem remained unaddressed: The target itself. Specifically, the fact that the target planet that we might be observing is not standing still. If it is like the Earth, it spins around its axis once every so many hours. And as it orbits its host star, its illumination changes as a result.

In other words, this is not what we are up against, much as we’d prefer the exoplanet to play nice and remain motionless and fully illuminated at all times.

Rather, what we are against is this:

Imaging such a moving target is hard. Integration times must be short in order to avoid motion blur. And image reconstruction must take into account how specific surface features are mapped onto the image plane. An image plane that, as we recall, we sample one “pixel” at a time, as the projected image of the exoplanet is several kilometers wide. It is traversed by the observing spacecraft that, looking back at the Sun, measures the brightness of the Einstein ring surrounding the Sun, and reconstructs the image from this information.

This is a hard problem. I think it is doable, but this may be the toughest challenge yet.

Oh, and did I mention that (not shown in the simulation) the exoplanet may also have varying cloud cover? Not to mention that, unlike this visual simulation, a real exoplanet may not be a Lambertian reflector, but rather, different parts (oceans vs. continents, mountain ranges vs. plains, deserts vs. forests) may have very different optical properties, varying values of specularity or even more complex optical behavior?

 Posted by at 12:06 am
May 042023

Claude still gets easily confused by math (e.g., reciprocal vs. inverse of a function), but at least it can now plot them as part of a conversation when we communicate through my UI:

And it has not forgotten to use LaTeX, nor has it lost its ability to consult Google or Maxima when needed. In fact, I am beginning to feel that while GPT-4 is stronger when it comes to logic or basic math, Claude feels a tad more versatile when it comes to following setup instructions, and also more forthcoming with details. (Too bad sometimes the details are quite bogus.)

 Posted by at 6:29 pm