Tony Vladusich

I'm a computational neuroscientist & software engineer. Colors, photos, brains, nature, science, software & chess, preferably all at the same time!

Author of The Appearance of Things: How the Principle of Relativity Shapes Our Visual World

Publications: https://scholar.google.com.au/citations?user=IrVz6ewAAAAJ&hl=en
My Book: The Appearance of Things: https://www.amazon.com/dp/B0HCVLM6T9

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tonyvladusich_at_mathstodon.xyz@momostr.pink

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Last Notes

2026-10-07 23:39:50 UTC

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"that's a problem many blokes *could* understand"
"blokes": are you becoming Scottish, John? 🤣

2026-10-02 22:13:18 UTC

While researching the interesting topic of active versus passive transformations in physics, I stumbled upon this fascinating paper by Witten from 2014.
In it, Witten discusses Einstein's efforts with Bergmann in 1938 to develop a unified theory of graviation and electromagnetism from the idea of a 5th dimensions, in the spirit of Kaluza–Klein theory. The main new idea that Einstein and Bergmann introduced was the "compactification" of the 5th dimension to a short length scale relative to the famililar 4 dimensions of space–time.
Apparently, Einstein balked at this idea and instead advocated that the 5th dimension be "wrapped" like a circle (whatever that means, apparently he worked out some calculation scheme). Witten criticises this last "misstep" but praises the "modern" conception of compactification.
If anbody is wondering, the resultant "scalar–tensor" theory turned out to be wrong because it incorrectly predicts the existence of a "massless scalar field". My understanding does not extend so far as to know why exactly that is inconsistent with experiment. Perhaps @npub1nf4…nqe4 can clarify?
In any case, some fascinating history.
https://arxiv.org/pdf/1401.8048

2026-10-02 21:21:24 UTC

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“I don't take drugs“
If you ever change your mind please re-record your standard model talk while high! 🤣

2026-09-30 20:08:19 UTC

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The Orange Thing has already decreed that these companies are to "self regulate", which we may translate to "have at it tech bros". The NWMs recommendations notwithstanding, the tech bros will continue to do what they want. There's an "arms race" going on between (at least) major tech companies to "create general artificial intelligence". All they care about is winning that race.
It will be interesting to see how the tech bros respond to this final section. If access is to be "equitable", how could it be restricted at all?
"We therefore advise the AI labs to grant the global mathematical community broad, equitable access to their publicly available models: this is a way both to accelerate progress and to ensure wide access to it."

2026-09-24 23:55:24 UTC

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Ha! I'm sure none of them have read about the "power structures" of organisations, academia included:
The theme that underlies all Foucault's work is the relationship between power and knowledge, and how the former is used to control and define the latter. What authorities claim as 'scientific knowledge' are really just means of social control. Foucault shows how, for instance, in the eighteenth century 'madness' was used to categorize and stigmatize not just the mentally ill but the poor, the sick, the homeless and, indeed, anyone whose expressions of individuality were unwelcome.
— Philip Stokes, Philosophy: 100 Essential Thinkers (2004)[188]
https://en.wikipedia.org/wiki/Michel_Foucault

2026-09-24 11:04:49 UTC

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Ultimately, I think the issues run far deeper than mathematics. The gathering concentration of power in the hands of the few completely unethical people who run these companies is deeply concerning for humanity.
First they came for the arts. Now they've come for mathematics. Next, I suspect, they will come for science, with dire consequences. I have grave concerns for the labour market in all endeavours of human thought.
What is needed is oversight, guardrails and effective laws to govern the behaviour of our unethical oligarchical tech overlords, but that's not coming any time soon, particularly in the US.

2026-09-24 08:55:29 UTC

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I’m also saying “fuck you” to the self-appointed advisory board! If you’ve never worked in the tech industry you may not understand the level of deceit, propaganda and outright lies these companies will promulgate for their own ends.
Any attempt to engage in good faith is simply more trouble than it’s worth. Let them release what they have. Folks will scramble over the feast while it lasts and things will eventually stabilise again. But don’t give them what they want, which is the legitimacy of naive attempt at good faith bargaining. We’ve seen how that ends with the current wave of fascism gripping the US and elsewhere. I see the ends of these companies in terms of their attempt to undermine systems of free thought and hijack the labour market.
As scientists, they are our enemy. We, who defend free thought and labour for little else than human knowledge and betterment, stand between them and the destruction of all we value.
There endeth my poor attempt at a Churchillian rhetorical speech! 🤣

2026-09-23 23:36:59 UTC

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Hard agree. Stated bluntly: Fuck big tech and the high horse of “theorem proof” it rode in on.

2026-09-15 09:06:23 UTC

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jfc John you had me freaking out for a second there! 🤣

2026-08-22 08:01:23 UTC

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well, pigs anyway ...

2026-08-17 10:35:33 UTC

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"Psychologists have a name for this tendency to think we understand things better than we do: the “illusion of explanatory depth.”"
I find this deeply ironic, having just written a book showing how the field of psychology itself "thinks" it understands psychology but does not really understand psychology.

2026-08-10 01:34:28 UTC

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That's pretty funny. I think there should be one more podium level for Scholze and Clausen (300 page foundational exposition, or some such)

2026-07-06 09:51:26 UTC

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That is a very apt metaphor!

2026-07-04 11:16:18 UTC

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Yeah, it's hard to be critical when there was literally no conception of science back then. Alhazen was an interesting figure who preceded Bacon by a couple of centuries. I love that Bacon was "regarded as a wizard". Now, that's one fucking cool dude! 🤣
https://en.wikipedia.org/wiki/Ibn_al-Haytham

2026-07-04 04:48:52 UTC

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Nice, I don’t think I’ve ever heard of him before!

2026-07-03 01:20:38 UTC

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Glad you find it interesting.
I find the practice of defining a theorem prior to a definition somewhat distasteful! 🙂

2026-06-11 22:44:26 UTC

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Probably up your alley?
https://arxiv.org/pdf/math/0609447

2026-06-11 21:36:50 UTC

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This is somewhat mind-boggling! Very nice.

2026-04-18 07:48:10 UTC

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BTW, Tao was clearly alluding to the "logs" as if they were trace data diagnostic of "how the LLM reached is conclusion". This is entirely false and misleading.
The logs too are textual extrusions, created by the machine in response to the prompts seeking more information.
Also, it occurs to me that you addressed none of my substantive points, other than to say you too are "concerned".
It's clearly a waste of time talking to you about this. So I won't do it again.

2026-04-18 00:43:01 UTC

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I fully agree!

2026-04-18 00:28:53 UTC

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"I've never done anything like that before."
Well, that's a first, I actually caused somebody to use an LLM! 🤣
"I think he's using this term "thought" as a quick shorthand for the text generated"
I suspect you are correct. But it is nonetheless sloppy to speak this way, especially for somebody who is extremely expert in speaking in precise language.

2026-04-17 23:58:05 UTC

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Of course there is nothing "magic" happening! (What would that even mean?)
The question is not whether they exhibit "strategic thought" or "agency" because nobody has a definition of that, so it's a pointless discussion.
The issue is that humans perceive such things in the outputs of these machines.
I think we should all be concerned about that sort of issue.
The perception of agency in machines misleads many people into believing the outputs are "true" or "correct".
Take, for example, this quote from Tao in the link you provided:
"Oddly, at no point in the published chain of thought does the von Mangoldt function make an appearance, so it sheds no light on how the LLM landed on that particular process. All in all, it's quite a chaotic internal thought process, with many dead ends, though to be fair many human mathematicians's thought processes during the initial stages of problem solving would likely also be similarly chaotic."
The use of words like "thought" here is extremely misleading and reflects his confusion about what is actually going on. The LLM "confabulates" (another dangerous anthropomorphism) a story about how it got to its output. There is no "chain of thought" happening there.
I do not think I am "blind ... to what this technology can do".
Quite to the contrary, I am quite aware.
I understand that you are really only interested in doing math there, as likely so too is Terry.
Yet I think we should all be concerned about the path humanity is taking here.
The argument that the machine can do something "much faster than I could" seems to be the main one used by grifters to undermine the rightful employment of human labour.

2026-04-17 22:52:42 UTC

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So, unlike you, I don't wax ecstatic when a textual extrusion machine happens to excrete something that makes vague sense to me.
I see the loss of human agency and labour.
I see the loss of a Great War.
It is utterly depressing.

2026-04-17 22:52:33 UTC

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Ok great, I've got a bridge to sell you too, pictured below.
I mean are you seriously arguing that these things are capable of strategic thought?
There no magic here. As I explained, it's a combination of training data, prompt data, context data, and skills data., all ultimately provided by humans.
The machine extrudes textual output that may or may not make sense to you.
Whether it makes sense to you or not is entirely coincidental to "reality".
Nothing more, nothing less.
Humans are programmed by evolution to see agency in things.
You, like so many others, are being seduced by your evolution.
Folks once saw agency in the Mechanical Turk.
You and Terry and others are all very smart people, far smarter than me, yet I cannot just watch on silently as you become soporifically seduced.
You may argue that these agents are just tools.
But you yourselves are now being used as tools.
In a war.
That war is being waged between the ultra rich, the tech bro grifters of the world, and everyone else.
And at huge cost to the intellectual property of humanity, the environment, and the socio--politico-economic systems of the world.
"Agentic" tools are being promoted as a magical panacea in just about every "problem space".
They are used in software engineering, just as in mathematics, so I am fully aware of their "power".
Yet where you see "originality" and "intelligence" I see the loss of human agency, opportunity, craft and, ultimately, peoples' livelihoods.
There will be a day in the near future when university administrators will "employ" agentic software to teach mathematics in classes, just because it is economically more viable than human labour.
https://media.mathstodon.xyz/media_attachments/files/116/422/418/858/991/414/original/d7ae59e4612eaa99.jpg

2026-04-17 21:13:02 UTC

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"My tentative theory is that these models are still quite weak at developing strategy and constructing novel coherent narratives (as opposed to explaining existing, human-generated, narratives, for which they are now rather good at)"
"the proofs was (sic) already in the training data"
"The people who spend their serious time using large language models to solve math problems know this is not true."
Where did the proofs come from, other than the training data?
These are not thinking machines. They do are never going to be capable of "developing strategy". They are statistical textual extrusion machines who state can be biased by additional prompt data, "context" and "skills" data.
What else can possibly be happening here? There's no magic spark of intelligence that's going to spontaneously emerge.
It is complete and utter nonsense coupled with pure wishful thinking to believe otherwise.

2026-04-10 07:45:09 UTC

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This is very interesting from a perceptual perspective.

2026-04-08 05:39:21 UTC

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I’ve been reading Gravitation by MTW. They seemed very unimpressed with Minkowski’s ict formulation. They even devote a small section to its “banishment”. 🤣

2026-04-08 05:14:02 UTC

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These “people” are the sacks of shit standing between humanity and the unthinkable. Will they act like human beings? Being sacks of shit, it’s not likely!
https://www.whitehouse.gov/administration/cabinet/

2026-03-06 23:16:00 UTC

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"We had thought we'd found them all."
How would we ever know this?

2026-03-03 22:21:25 UTC

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So he got within a factor of 2 just through dimensional analysis?

2026-03-01 21:00:47 UTC

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This is literally the plot of Wag The Dog.

2026-02-28 23:08:51 UTC

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😒

2026-02-25 05:11:04 UTC

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“counter-revolutionaries”
🤣👏

2026-02-23 23:16:34 UTC

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Or do as politicians do: Now, the real question is ….
And proceed to answer THAT question!

2026-02-23 22:15:55 UTC

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🤣

2026-02-23 08:15:58 UTC

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🤣 Nice metaphor. And totally fair enough! This sort of "blobby" discussion is my jam. I enjoy trying to find the form of the blobs. It's not for everybody and it's bloody hard work (sometimes you never see the punches coming!).

2026-02-23 07:40:02 UTC

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If you want to see a real shit show, Google “nature versus nurture”. This argument has been going for over a century without resolution. It’s largely a poorly defined set of constructs. So nobody can ever agree because nobody ever understands what the fuck either side is saying. It’s such a common pattern in soft sciences. It’s a chicken and egg problem every time (not pardoning the pun).

2026-02-23 07:27:12 UTC

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Lol. Well I’m glad something I’m saying does!!! 🤣

2026-02-23 07:26:17 UTC

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I think you understand it perfectly well. Our models of the world are cognitive constructs, no more, no less.
I’m sorry if you don’t enjoy such conversations. But they sit at the heart of the endeavour we call science, whether you like it or not.

2026-02-23 05:00:38 UTC

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These are reborn chicks. They know nothing. And the idea that they are born innately able to associate specific sounds to specific shapes is quite frankly laughable. See, for example, the entire history of animal behavioural studies.

2026-02-23 01:18:13 UTC

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Riiigghhht. But you see my point, yeah?

2026-02-23 00:45:48 UTC

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Can we make this mapping "concrete"? I say we fundamentally cannot and that any "resemblance" between cognitive and physical constructs is, in a fundamental and well-defined way, a "fiction of coincidentals".
When a magician saws a person in half, for example, we are perceptually convinced of the veracity of the act, although no such physical operation actually occurred (hopefully).
The cognitive and physical have thus become fundamentally dissociated by the visual performance of the magician.

2026-02-23 00:41:28 UTC

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Of course, everything has a physical basis.
But to say one thing "cuts" another thing is a cognitive construct that bears some vague and unspecified relationship to the physical act of "cutting".

2026-02-23 00:39:26 UTC

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My point is that sounds and shapes are cognitive constructs. Whether a chicken brain has evolved to create such constructs and associate them is the question at hand.
I say it's unlikely for the reasons given, and probably for many other reasons (you've pointed out one with the difference between the human mouth and chicken beak).
The problem is that we are taking as given the very constructs that require explanation. This is why psychology has been such an utter failure as a field; namely, the failure to clear delineate the physical from the perceptual and to identify the mapping form one to another (hint: there is none in the sense of a mathematical homomorphism).
This is the problem I tackle in my book, btw.

2026-02-23 00:22:10 UTC

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Sure but language "requires" cognition and perception.
Constructs like hard and sharp are cognitive, not physical.

2026-02-22 23:51:24 UTC

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How is that not linguistic? Sounds and shapes are cognitive constructs not physical ones!

2026-02-22 22:53:21 UTC

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I’m calling BS on this one, even without reading the paper.
If you want to know why, search Google for Clever Hans.
I spent my PhD years studying honeybee behaviour. Animal experiments are very often biased by the human experimenter in unconscious ways.
It just seems too far fetched for me: A linguistic effect manifest in baby chicks? I doubt it.
Having said all that, I should read the paper and try to pinpoint specific weaknesses. But I’m busy and lazy.

2026-02-04 22:56:41 UTC

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What do you think they are getting out of the relationship in return?

2026-02-03 23:21:38 UTC

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Is Google paying you?

2026-01-15 05:15:38 UTC

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To be fair, the headline does say "a" universe, not "our" universe! 🤣
Woit took a stronger view than you in his latest blog post ("just more string theory hype"), as I'm sure you know.

2026-01-15 01:14:32 UTC

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But they seem so proud of themselves!
https://media.mathstodon.xyz/media_attachments/files/115/896/462/022/319/565/original/f31e02eeaa90ebb3.png

2026-01-13 20:50:09 UTC

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Nicely spruiked!

2026-01-11 23:56:44 UTC

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By “law of continuity” I am guessing Clifford meant a “continuity equation”?
https://en.wikipedia.org/wiki/Continuity_equation

2026-01-10 02:29:20 UTC

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I'm reading this version/translation:
https://www.fourmilab.ch/etexts/einstein/specrel/www/

2026-01-10 01:51:41 UTC

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BTW: I started rereading "On the electrodynamics of moving bodies" the other day. Section 3 is the key part, but it's actually pretty hard to follow his reasoning, I find. He introduces a bunch of new coordinate systems that are hard to keep track of without any diagrams. It's surprisingly opaque given how clear most of his writing usually comes across.

2026-01-10 01:47:39 UTC

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Indeed. I myself have had to satisfy myself with the joy of discovery.
Hopefully my forthcoming book will help to settle the record straight, though!

2026-01-10 00:19:47 UTC

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Poor Voight!
https://media.mathstodon.xyz/media_attachments/files/115/867/935/293/924/938/original/c1edc8d8e6cae24d.png

2026-01-07 20:41:41 UTC

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I for one would be very interested in your findings!

2026-01-06 10:37:35 UTC

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What?! My first degree was in biology and I did not know that! Wild indeed.

2026-01-05 22:53:05 UTC

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That’s a pretty ballsy paper!

2025-12-31 12:07:48 UTC

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Axiometisation of any scientific field is a noble goal, just incredibly difficult!

2025-12-31 04:28:10 UTC

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It was a fun video. The part on Kakeya sets was particularly interesting.

2025-12-31 04:27:13 UTC

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“Hilbert's sixth problem was a proposal to expand the axiomatic method outside the existing mathematical disciplines, to physics and beyond.”
And beyond! 🤣 Good luck

2025-12-26 01:33:45 UTC

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Do you know about the tritone paradox?
https://en.wikipedia.org/wiki/Tritone_paradox

2025-12-22 00:35:20 UTC

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My understanding is that visitors to the US now are routinely required to log in to social media accounts for border officials to peruse their content. Should they find material to their distaste then folks can be detained or deported. I don’t know the extent to which this sort of authoritarian control is actually conducted in practice nor whether it applies to US citizens. But I do know people who have cultivated fake social media accounts to side step the problem.

2025-12-21 21:26:27 UTC

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I hope you've cultivated your fake social media accounts!

2025-12-21 21:13:47 UTC

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You thinking of this?
https://en.wikipedia.org/wiki/Characteristica_universalis

2025-12-16 19:56:33 UTC

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it's a joke

2025-12-14 12:20:55 UTC

I discovered this effect while tinkering around: I perceive vertical lines between the black and white disks, but only in my peripheral vision.
Edit: Updated with a stronger version.
https://media.mathstodon.xyz/media_attachments/files/115/717/907/680/177/720/original/8eee36138210463d.png

2025-12-12 23:45:23 UTC

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Whoa! I did not know about projective invariants. Even psychologist James Gibson never mentions them despite creating an entire theory of vision based on the concept of … projective invariants. Weird. But that’s psychology for you. Always missing the critical point (projective humour there).

2025-12-12 23:41:05 UTC

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It took me a few attempts before I understood your text. The genius of the Riemann sphere is how it simplifies the description of points at infinity by compactifying them to a single point via stereographic projection!
https://en.wikipedia.org/wiki/Riemann_sphere

2025-12-04 07:13:32 UTC

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It’s so weird how Nordström’s theory was kinda sorta right but ultimately not. I mean it predicted that mercury precesses but it predicted the wrong direction and magnitude!
I guess it proves yet again that Einstein’s intuition wrt physics was preternaturally refined. It seems he became more captivated by mathematics later in life?

2025-12-03 11:33:05 UTC

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I don’t ever recall hearing the word spruik spoken when I lived in the US either. I think it’s likely much more common in the UK and Australia though. So you now have a nifty new word to spruik in front of your new Scottish friends!

2025-12-03 11:26:59 UTC

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“Newtonian gravity is inconsistent with special relativity”
Right, I was not considering the other aspects of our universe that demand explanation not provided by Newtonian mechanics. When those are factored in then there is of course no contest. Thanks for the link, I will check it out. I love delving into the history of physics!

2025-12-03 00:31:19 UTC

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"General relativity gets you gravity as well, but the math is far more advanced"
It also sheds the need in Newtonian mechanics to invent fictional forces and it let's us assert that ANY given reference frame can be considered at rest with respect to any other frame, which is a big win too. So I'd argue it is more parsimonious in this respect. Whether the added mathematical complexity is enough to offset these added bonuses is an interesting question but my gut feeling is that it does.
BTW, John: I see that you've put up the 4th lecture in your series on the Standard Model on YouTube but I've not seen you spruik it here!

2025-12-02 04:35:39 UTC

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You mean aside from the special/general principle of relativity?

2025-11-13 03:53:19 UTC

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Maybe something of this flavour?
https://arxiv.org/pdf/quant-ph/9609002

2025-11-13 03:16:02 UTC

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John, when talk about gauge theory here are you specifically referring to fixing the Lorenz gauge or something different?
You motivated the connection between EM and gauge theory in terms of QM, but is this necessary? Can the motivation for fixing the Lorenz gauge be approached entirely classically? The wikipedia article seems to imply as much but then it also briefly mentions QM without any context, so it leaves me confused.
https://en.wikipedia.org/wiki/Lorenz_gauge_condition

2025-11-13 01:32:27 UTC

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"live the rest of their life haunted by this vision"
so it's a case of "you only olo once", hence yooloo

2025-11-11 10:46:28 UTC

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It’s not that I don’t understand the mechanics of special relativity. I think I do, at least. I’m more interested in the question of how physicists interpret the Lorentz transform as v approaches c since t’ and (say) x’ become singular.

2025-11-11 04:33:12 UTC

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So what is the standard thinking about the meaning of the blow-up of the Lorentz transform as an inertial frame approaches the speed of light? It’s just a physical impossibility? If so, how do massless particles like photons figure in this picture? Or is special relativity only strictly applicable to massive particles?
Apologies if these are dumb questions. I mostly just have dumb ones so that’s what you get …

2025-11-11 00:00:37 UTC

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Yeah, I don’t have any specific ideas to follow up this “great idea”! 🤣
It seems like it could be fun to think about though if somebody can come up with a concrete example.

2025-11-10 11:11:44 UTC

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I can’t find much info about him. Wikipedia says he got rich from a patent yet I found a link to what must’ve been the early 20th century equivalent of a Go Fund Me campaign because of his pending eviction from the family home! 🤣
https://www.science.org/doi/10.1126/science.83.2160.499.c
https://en.wikipedia.org/wiki/Ludwig_Mach

2025-11-10 10:40:59 UTC

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Ha, I just discovered that Ernst Mach’s son was partly responsible for a quantum interferometer.
https://en.wikipedia.org/wiki/Mach%E2%80%93Zehnder_interferometer

2025-11-10 10:05:46 UTC

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It would’ve been fascinating if he’d accepted the tenets of quantum field theory. I can’t help feel that there’s some beautiful thought experiment involving moving clocks near light speed or some such and the double slit experiment that could’ve been illuminating? I guess if there were somebody would’ve discovered it by now?

2025-11-10 05:54:32 UTC

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Interesting remark from the first Goenner paper:
"If there is an enigma left in the scientific part of Einstein’s life, then it occurs here, in the area of unified field theory. As judged from his ambitious goals and as seen from the aspect of lasting scientific value, not only did Einstein’s endeavours – from the affine approach to the teleparallel theory – lead nowhere, but sometimes they were also quite behind what others knew already, as in Kaluza–Klein theory and in the area of spinors. Einstein also was not very fruitful in developing, conceptually, his particle model beyond the image of regular field concentrations. Einstein knew only too well how disconnected his various unified field theories were from the possibility of them being checked empirically. He, and everybody else working in the field, did not succeed in extracting from one of the unified field theories an example of a new physical effect of gravito-electromagnetic nature to be tested by experiment or observation. Unlike in his previous scientific career where he was most ingenious and prolific in devising (thought-) experiments, now Einstein’s physical intuition seems to have been buried under formal structural thinking."

2025-11-08 21:40:20 UTC

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Those Goenner papers are an absolute goldmine! It's gonna take me a while to work through them.

2025-11-08 11:42:18 UTC

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Thanks for the links and snippets! I also found this interesting article, which talks about Mach’s principle in terms of understanding why gyroscopes work.
https://www.americanscientist.org/article/the-forgotten-mystery-of-inertia

2025-11-07 22:20:07 UTC

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Oh man, things are getting murky!
The Wikipedia page for Mach's principle says:
"Because intuitive notions of distance and time no longer apply, what exactly is meant by "Mach's principle" in general relativity is even less clear than in Newtonian physics and at least 21 formulations of Mach's principle are possible, some being considered more strongly Machian than others."
To be honest, I've never really understood what is the actual statement of Mach's principle. Wikipedia just says it's "imprecise hypothesis" and gives the usual statement about centrifugal force, which mystifies me. I mean, we are just back to Newton's bucket question, are we not?
Surely this is all best understood in terms of the equivalence principle of GR? That is, in terms of the equivalence of inertial and gravitational mass: centrifugal force is then felt by virtue of the acceleration of points on the spinning frame with respect to absolute spacetime, no? Would centrifugal force not be felt in a universe with zero mass anywhere? I'd think that it would?
And this brings us to the really interesting part for me; namely, the statement of spacetime as absolute. Why should that be? Why is everything else relativistic except spacetime? But perhaps I am just wasting your time at this point ...
Interesting aside: Mach made important contributions to the study of vision! So too did Helmholtz (of the Helmholtz decomposition and principle of conservation of energy). In fact, Helmholtz is considered by many folks to be the founding father of modern vision science.

2025-11-07 08:56:50 UTC

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Thank you so much for the wonderful response! I will now read what must be read.

2025-11-06 22:31:08 UTC

Questions for physics folks
Do physicists consider General Relativity to be a superior description of nature compared to Newton's laws in terms of its intrinsic ability to account for "fictitious forces", such as centrifugal and Coriolis "forces"?
Correspondingly, is it a correct statement to say that Newton's laws of motion only strictly apply in inertial frames of reference and therefore GR provides a more parsimonious account of the concept of "force"?
I've tried to find historical references that remark upon the ad hoc nature of the addition of "fictitious forces" to Newton's laws but it doesn't seem to me that physicists of the 17th - 19th centuries were overly concerned by these issues.
Is that a fair appraisal?
Note that I am not asking whether GR is a better description of nature than Newton's laws in general but rather with specific reference to the "fictitious forces" and the question of whether physicists actually considered them a fundamental issue that required a better or more parsimonious solution.
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2025-10-28 02:08:13 UTC

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The FAQ is an amazing resource thanks! I’ve already spent some hours in it, look forward to learning lots more.

2025-10-24 21:59:24 UTC

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I just meant that it’s one thing to have a qualitative understanding of things and another to be able to write down the equations and solve specific problems. The Feynman diagrams probably help to bridge that gap a bit, I guess.
When I was younger I intended to study physics at university but I needed to work really hard to stay on top of the mathematics. If a course like yours existed I might have stuck with physics longer.
Alas I switched to psychology and neuroscience and the rest is history. I don’t regret my decision one bit. I’ve stayed interested in physics my whole life and understanding physical principles has helped shape my understanding of neuroscience and psychology. Indeed that’s the very heart of the book I’m currently writing!
Anyway, thanks for the wonderful pedagogy. It’s appreciated by us dilettantes.

2025-10-24 10:01:15 UTC

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I finally got around to watching the video. It's fantastic! I like the "fun course" approach. It provides me with an ideal illusion of understanding 🤣. Keep it up!

2025-10-23 20:58:54 UTC

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Thank you! That makes perfect sense to me.

2025-10-23 09:30:30 UTC

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Do mean free electrons in vacuum? It would seem weird for a free electron to emit a photon because such emissions usually involve energy transitions across orbits on the atomic shell, right?

2025-10-14 21:41:11 UTC

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Any mention in the paper why 3 bursts and why those timings?

2025-10-08 21:10:00 UTC

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In our own universe in this case!

2025-10-08 07:28:59 UTC

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This discussion on Greg’s webpage about the dual to the Pythagorean theorem is fascinating. I used this dual idea in one of my papers modelling visual perception to prove the equivalence of two ostensibly different models of transparency.
The paper is here: https://www.researchgate.net/publication/235777134_A_reinterpretation_of_transparency_perception_in_terms_of_gamut_relativity

2025-10-06 10:37:32 UTC

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