The Eternal Doorman

Talk given in Oxford in 2008. See  David Albert Talking Complete Nonsense .  You can't see his slides, but the 2008 paper he refers to is `What is a Thing?': A Topos Foundation for Theories of Physics: I. Formal Languages for Physics A. Doering and C.J. Isham.  A review of some work from a decade earlier: Chris Isham and Jeremy Butterfield Some Possible Roles for Topos Theory in Quantum Theory and Quantum Gravity . See also other publications mentioned in nlab . The term he coined is dasein ization.  1:02:05 "... the most important thing is: how do you construct,..." A model for a bullshit ontology?  1:03:33 Urs Schreiber on state representations. See  The Category Enriched over the Category of Finite Sets, The Finitely Triangulated Manifold and the Magnitude of a Finite Category .  I think this is how you should look at the epistemological structure of physics. See  John Norton on "Landauer's Principle" . Subscribe to Oxford Quantum Video...

I missed the first 30 minutes, but I made some comments: See Matt Prewitt's substack:  https://mattprewitt.substack.com/  and his web page  https://mattprewitt.com/ . Subscribe to Topos Institute .

Ernst Mach was of the opinion that statistical physics was the proper foundation of dynamics. See  David Albert Talking Complete Nonsense . See from 33:06 :   55:26 Thermodynamic entropy is a selection principle which picks out the spontaneous paths closed systems take through configuration space. 1:04:55  Thermodynamic considerations are what led Einstein to his light quantum hypothesis too. See Norton's Mach's Principle Before Einstein and How Hume and Mach Helped Einstein Find Special Relativity . Also Ernst Mach's (1882)  The Economical Nature of Physical Inquiry : The greatest perfection of mental economy is attained in that science which has reached the highest formal development, and which is widely employed in physical inquiry, namely, in mathematics. Strange as it may sound, the power of mathematics rests upon its evasion of all unnecessary thought and on its wonderful saving of mental operations. Even those arrangement-signs which we call numbers are a ...

51:47 Question about set theory vs type theory. I don't know that there was ever a split. The impression I get is that type theory was developed as a way to reason formally about set theory, and then that structure turned out to fit well with constructive mathematics and intuitionistic logic. So the people who study type theory tend to be constructivists. See  About Logic - Is Mathematics a Story?  and  Andrej Bauer - Models of intuitionism and computability .  Subscribe to  About Logic .  Thorsten might have a chapter on this in his book, it's all about how people who can't count can decide whether or not two sets are the same size:  Subscribe to  Thorsten Altenkirch .  See also the following interviews: About Logic Interview with Deborah Kant About Logic with Andrej Bauer About Logic - Interview with Dana Scott Joel Hamkins interviewed on About Logic

From  Eron Woolf on Why Open Source is Failing : I posted something on the FUTO Zulip and thought I'd copy it here: Hello FUTO types, I was just rewatching the short talk by Matt Mikhailov and Vincent McKibbon on open hardware blues https://youtu.be/YLn4vnfchaE and the discussion with Daniel C. on the Rockchip bringup https://youtu.be/5klMcYG-AP0 and I thought I'd post another ten cents worth here. It's not only the directly connected hardware that's being locked down, it's the network infrastructure too. Looking at the crazy stuff that people have to do to "punch holes" so that they can send and receive data peer-to-peer without publicising an IP address. This is in a sense dual to the problem of locked-down hardware, and they actually exacerbate each other. There are security vulnerabilities in the proprietary hardware and firmware, and the networks will route hostile traffic to compromise the crappy router your ISP installed in your house, but that s...

Subscribe to Olive Badger .

I got a bit lost there, ... but it does sound like there are a lot of things you can say about computability beyond just that "uncomputable functions exist".  It also sounds like Andy Pitts doesn't like modal logic.  I wonder what the quote was that he ended the talk with. I think it was something Jaap Van Oosten wrote somewhere. See  Basic subtoposes of the effective topos  (2013) by Sori Lee and Jaap van Oosten. Subscribe to  De KNAW . Here's a May 2022 talk on the countable reals. Subscribe to Topos Institute . After listening to these two talks last night I dreamed that someone was explaining to me how you could build computational circuits using a kind of "co-clocking". In this scheme the clock was an index into a type which was the successive ticks, and it meant that there was a notion of continuity in temporal evolution which was not the sort of thing Albert Einstein would have immediately understood. It was a really interesting dream! See David Albe...

I am having serious trouble listening to this stream of complete crap he's talking. I have only managed an hour so far, with a few breaks. My comment : 17:41 I can't take seriously statements like this one "The laws of Newtonian theory determine the complete physical condition of the world, given the complete physical condition of the world at some earlier time." This was an hypothetical argument made by Laplace and it's become something else entirely, solely through mindless repetition ever since. Nobody seriously believed you could learn anything about the world under this hypothesis, did they? It reduces knowledge to infinite initial information and time becomes meaningless, therefore knowledge cannot change. That's just not an interesting idea at all. No meaningful theory, complete or otherwise, can start from material and information without any understanding subject for whom that information is meaningful. Any such theory is vacuous. These vacuous theo...

Sounds like this heatwave in Europe and the UK would have been much easier to handle if there were a lot more beavers.  Subscribe to Hope .