Science – Page 2 – Spinor Info

Strange Einstein quotes

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.”

How not to foobar something…

Electronics, Space No Responses »

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.

Google foobar

Mathematics, Personal, Programming 2 Responses »

Nov 302023

So the other day, as I was doing a Google Search (can’t exactly remember what it was that I was searching for but it was machine learning related), up pops this invitation to participate in a challenge.

Turned out to be the Google Foobar challenge, Google’s secret recruiting tool. (Its existence is not really a secret, so I am not really revealing any great secrets here.)

Though I have no plans to become a Google employee (and I doubt they’re interested in me on account of my age anyway) I decided to go through the challenge because, well, it’s hard to say no to a challenge, and it was an opportunity to practice my Python skills (which need a lot of practice, because I have not yet used Python that much.)

Well, I did it. It was fun.

More importantly, I enjoyed it just as much as I enjoyed similar challenges as a math geek in my early teens. And if that’s not a gift from life, I don’t know what it is.

And yes, I am now much better at Python than I was just a few days ago. I certainly appreciate why the language has become popular, though I can also see its non-trivial pitfalls.

The state of scientific publishing

Cybernetics, Physics, Science No Responses »

Nov 302023

This morning, like pretty much every morning, there was an invitation in my inbox to submit a paper to a journal that I never heard of previously.

Though the unsolicited e-mail by itself is often an indication that the journal is bogus, predatory, I try to be fair and give them the benefit of the doubt, especially if the invitation is from a journal that is actually related to my fields of study. (All too often, it is not; I’ve received plenty of invitations from “journals” in the medical, social, biological, etc., sciences, subjects on which I have no professional expertise.)

So what are the signs that I am looking for? Well, I check what they published recently. That’s usually a good indication of what to expect from a journal. So when I read a title that says, say, “Using black holes as rechargeable batteries and nuclear reactors,” I kind of know what to expect.

Oh wait. That particular paper appears to have been accepted for publication by Physical Review D.

Seriously, what is the world of physics coming to? What is the world of scientific publishing, by and large, coming to? Am I being unfair? Just to be sure, I fed the full text of the paper on black hole batteries to GPT-4 Turbo and asked the AI to assess it as a reviewer:

Saying clever things

Cats, Personal, Physics, Politics No Responses »

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…

My latest papers

Astronomy, Personal, Physics No Responses »

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.

More lensing

Astronomy, Personal, Physics No Responses »

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.

Gravitational lenses

Astronomy, Mathematics, Physics No Responses »

Oct 082023

I am simulating gravitational lenses, ray tracing the diffracted light.

With multiple lenses, the results can be absolutely fascinating. Here’s a case of four lenses, three static, a fourth lens transiting in front of the other three, with the light source a fuzzy sphere in the background.

I can’t stop looking at this animation. It almost feels… organic. Yet the math behind it is just high school math, a bit of geometry and trigonometry, nothing more.

NB: This post has been edited with an updated, physically more accurate animation.

Hungarian Nobels

Physics, Science No Responses »

Oct 052023

I don’t know much about attosecond light pulses but my wife and I did note that one of the recipients of this year’s physics prize was a physicist who studied just a year ahead of Ildiko at ELTE (Eötvös University). She doesn’t recall if she ever bumped into Ferenc Krausz, though.

And of course one of the recipients of the Nobel prize in physiology or medicine was Katalin Kariko, for her groundbreaking work in mRNA vaccines. Well-deserved indeed! I actually know (a little bit) more about mRNA vaccines than about attosecond physics, which might seem odd, considering that physics is my home turf, and organic chemistry is like an alien landscape. But the generation of ultrashort photon pulses is a very specialized field of study, to which I never paid much attention.

Anyhow, Kariko and Krausz are now added to that long list of scientists who were born, and studied in, Hungary, but who eventually ended up abroad, where they did the bulk of the work that earned them this recognition.

Heat wave

Local Ottawa, Weather and Climate No Responses »

Oct 032023

Here’s my phone screen as of a few minutes ago:

That’s in Centigrade of course.

What can I say? OK, our balcony thermometer only shows 28.3 C. Even so… not exactly typical early October weather for Ottawa.

From out of this world

Space No Responses »

Sep 292023

I’ve been meaning to mention this: A few days ago, the sample capsule of the OSIRIS-REx mission returned safely to the Earth, carrying inside a sample taken from the asteroid Bennu.

This is a remarkable achievement, ~~the first~~* successful sample return of its type. I wonder what we will learn from the material that was obtained, but I’m sure it will reveal some intriguing secrets, especially about the history and formation of the solar system.

Love the way the capsule was sitting on the ground, upright, not even tilted. Could it be more picture perfect than this?

I am also mildly (but pleasantly) surprised that I have not heard any panicmongering about a capsule bringing back extraterrestrial microbes or whatever. OK, I wasn’t specifically looking but still. It’s a relief.

* I don’t know what possessed me when I wrote “first”; granted, OSIRIS-REx brought back a lot more material, supposedly, but the first successful such missions were the two Hayabusa missions of the Japanese Space Agency.

Falling antimatter

Physics No Responses »

Sep 292023

OK, not exactly a surprising result but still, a fantastic experimental achievement: Yes, Virginia, antimatter falls downward.

Why is this important? Well, we kind of knew that it was inevitable. I mean, if antimatter were to fall upward, it’d have meant that our entire understanding of gravitation is wrong. That even our understanding of special relativity is probably wrong.

So it was a rather safe bet that antimatter follows the same geodesics as normal matter and falls downward.

But physics, lest we forget it, is ultimately not about erudite speculation. It is about experiment and observation.

And this amazing experiment achieved the almost impossible: it observed antihydrogen atoms in a vertical vacuum chamber at cryogenic temperatures and, as expected, most of those hydrogen atoms ended up at the bottom.

Moffat’s finite quantum field theory

Personal, Physics No Responses »

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 arxiv.org 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.

Look before you leap…

Personal, Physics No Responses »

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?

Chandrayaan-3

Space No Responses »

Aug 232023

Chandrayaan-3 landed safely on the Moon, cementing India’s position as a space superpower.

What can I say? Congratulations! Not sure who the gentleman is in this image that I saw on Twitter, but he certainly looks happy.

RIP, Luna-25

Politics, Space No Responses »

Aug 212023

Russia’s first probe to the Moon in nearly half a century, Luna-25, has crashed.

It would be easy to react to the news with glee, with schadenfreude. We are, after all, talking about a crash that denied a propaganda opportunity to Putin’s Evil Empire (maybe not quite as evil as Stalin’s regime but more evil, to be sure, than the USSR ever was in my lifetime).

But space exploration transcends, always transcended, national boundaries. Our petty squabbles look pretty… well, petty from the Moon. Chances are, if human beings are still around with an advanced technical civilization a millennium from now (or, if our machine descendants are still around) they’re far more likely to remember Armstrong’s first step on the Moon than Russia’s attack on Ukraine, the Cold War, or even WW2.

So this crash is sad news, Putin or no Putin. I hope India’s probe, Chandrayaan-3, is more successful. Fingers crossed. Things are looking good for now but it has yet to accomplish a tricky landing.

Methane

Nature, Weather and Climate No Responses »

Aug 182023

And then there is this. The rate of increase in atmospheric methane has been rising since the mid-2000s. The curve is becoming ever steeper.

Surprisingly perhaps, it’s not from natural gas producers, industry, or vehicles. Not even cow farts.

It’s apparently in large part coming from tropical wetlands. Climate change is still indirectly responsible as it is the changing climate that changes the vegetation that, in turn, results in more methane production. But the consequences of this rise in methane levels can dwarf anything CO2 will do. A “termination-level” event, they call it, which sounds alarming and it should be: even though it does not mean our immediate termination, it may mark the termination of an epoch, just as in the past, when similar rises in methane events marked the end of the ice ages. Except that there’s no ice age at present.

Yellowknife

Canada, Nature, Weather and Climate No Responses »

Aug 182023

Yellowknife is not a large city by Ontario standards, but it is the capital city and the largest community in the Northwest Territories of Canada, with over 20,000 inhabitants.

And it is about to be evacuated entirely today, because of the imminent wildfire threat.

Yes, it’s a faraway place but it is still incredibly scary that tens of thousands of Canadians are uprooted, some taking their cars, some boarding evacuation buses or flights, fleeing their homes, traveling through landscapes that are like warzones, with burned buildings and burnt-out vehicles often in sight.

No, I won’t rant about climate change. There can be other contributing reasons behind this unprecedented wildfire season, though I bet climate change is by far the most significant contributor.

I wonder what prompted N.W.T. authorities to take this drastic step. I may be wrong but I have a feeling that the devastation in Maui was a wake-up call, and they wanted to avoid a similar disaster. Having said that, I sincerely hope that Yellowknife will be spared and its inhabitants can return in a few days.

Pollinating insects

Biology, Nature No Responses »

Aug 112023

Here’s a sunflower, which grew in a large planter right here on our driveway, as photographed by my beautiful wife just the other day (before Ottawa got an incredible deluge of rain):

If you look closely, there’s a bumblebee in the flower. May there be more! I keep reading about the crisis pollinating insects face worldwide, sometimes accompanied by tragic images of entire beehives, dead. Pollinating insects play an essential role in nature, including our food supply. And they seem to be in serious trouble. Climate change, habitat loss, reckless use of insecticides, whatever the reason, it might be a good idea to take this problem seriously before it is too late. (Just don’t turn it into politics please. It’s a real crisis, not fodder for virtue-signaling by wannabe liberals or progressive-bashing by wannabe conservatives.)

A scary chart

Weather and Climate No Responses »

Aug 062023

I don’t usually like climate panicmongering but this chart that I came across today is… Well, see for yourself.

These are ocean temperatures, by the way. Oceans are supposed to be large, stable reservoirs of heat. Which they probably are, except that surface temperatures also reflect changing patterns like changing ocean currents.

This massive deviation from the 20+ year average (more than four sigmas!) is difficult to comprehend. What it says about the changing climate, I have no idea, but it is unlikely to be good news.

If only we stopped making this political. OK, well, it is of course political in the sense that we need to make collective, i.e., political decisions on how we manage Spaceship Earth. But it should not be political in the sense that the facts are not political, and the proposed solutions should be weighed by their feasibility, efficacy and social impact, not political palatability.

And for heaven’s sake, stop the dumbed down oversimplifications. Next time I hear about someone emitting “carbon”, I’ll scream. Carbon is solid at room temperature. Carbon is not carbon dioxide, just as hydrogen is not dihydrogen oxide. I have yet to see anyone drinking liquid hydrogen… or emitting carbon. Perhaps the first step to take is to give people a more decent education in the sciences so that they actually understand what carbon dioxide is, what it does in the atmosphere, what “four sigma” means, and what things like heat reservoirs are in a climate system? Is that really too much to ask? Am I being a silly elitist or something?

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