Jenn Grant - The Bells Are Ringing
From Jennytown, in Gaza.
Featuring the children's choir of Halifax, NS and Southern G * z a
All proceeds of the sale and stream of this song go to The English Learning Tent
A school for the children in Southern G * z a
Please buy and share here!
https://jenngrant.bandcamp.com/track/bells-are-ringing
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Avshalom Elitzur on Kurt Jaimungal's Theories of Everything Podcast. It's a very interesting interview but I'm barely an hour into it.
43:07 John Cramer's transactional interpretation of Quantum Mechanics: The transactional interpretation of quantum mechanics, Rev. Mod. Phys. 58, 647 (July, 1986) is based on Wheeler and Feynman's work on absorber theory in electrodynamics: The basic element of this interpretation is the transaction describing a quantum event as an exchange of advanced and retarded waves, as implied by the work of Wheeler and Feynman, Dirac, and others. The transactional interpretation is explicitly nonlocal and thereby consistent with recent tests of the Bell inequality, yet is relativistically invariant and fully causal. See also Curt's 5-minute Substack piece https://curtjaimungal.substack.com/p/the-interpretations-of-quantum-mechanics.
I stopped worrying about retro-causality and grandfather paradoxes almost as soon as I read Roger Penrose's objection in The Emperor's New Mind. Penrose points out that you don't need free will to cause a grandfather paradox, because you can just make a message-repeater machine which deterministically stores messages it receives from its future self and then sends them back to itself later on. If it also has two lights on it, one of which is lit if it has received a "yes" message and unlit if it received a "no" message and the other which is lit if it has received a "no" message and unlit if it has received a "yes" message then the lights will flicker randomly whenever the channel is not working properly (i.e. if the "yes" messages are being turned to "no" and vice versa). So I never really had a problem with faster-than-light signalling. Am I missing something?
1:28:50 He has a challenge for foundations experts, ... See Nonlocal Position Changes of a Photon Revealed by Quantum Routers (2018).
1:33:00 Relativity and the speed of light discussion. This is the most easily comprehensible part of the interview, I found.
1:48:01 The quantum version. This also makes far more sense to me than almost anything else I've heard about Quantum Mechanics!
1:57:03 Human scale cosmology! See Lee Smolin's comments at 3:03 in this discussion he had during a boat trip around SF Bay.
1:57:32 On the way this quantum time-creation-by-measurement process produces forces, momentum etc. I'm just thinking aloud here: so you have these scientists in their laboratories, and they're measuring the position and momentum of balls by, say, dropping them from a really tall retort stand through laser beams which measure the position and momentum in time and record it all in a computer. Then they do this experiment hundreds of times, dropping the ball from all these different heights and measuring the position at all all these different intervals and they plot a graph and add their error bars, and after they've done this for a week or so, they publish a paper that to such-and-such a confidence level, the rate of change of momentum due to gravity is such and such a value, in Newtons. And they also do all these different measurements to determine (with error bars and confidence intervals) the mass of the balls they use in their experiments, using the SI Mise en pratique for the definition of the kilogram, which is by taking the fixed numerical value of the Planck constant h to be 6.626 070 15 × 10 –34 when expressed in the unit J s, which is equal to kg m 2 s^{–1}, where the metre and the second are defined in terms of c and ∆νCs. The second and metre are themselves defined by exact values of the hyperfine transition frequency ∆νCs of the caesium 133 atom and the speed of light in vacuum c. The effect of this definition is to define the unit kg m2 s^{–1} (the unit of both the physical quantities action and angular momentum). Together with the definitions of the second and the metre this leads to a definition of the unit of mass expressed in terms of the Planck constant h. You can indeed kind of see how what Elitzur is talking about could happen!
As to how we experience that momentum as a physical force. Here's Lee Smolin about a year ago, talking about qualia. He has Parkinson's disease. I wonder how that effects the sensations associated to momentum and inertia? Maybe I'll find out one day!
2:06:04 I didn't know Einstein was hoping to have a relativistic picture of electromagnetic forces too! That's a really wild idea! I mean, how the hell is space-time going to be able to decide how to curve then! See Jade on The Integral Formulation of Maxwell's Equations:
And I just realised that I had completely forgotten about Ilya Prigogine's beautiful book From Being to Becoming: Time and Complexity in the Physical Sciences.
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That talk by Lee Smolin is really good: Quantum Cosmology & The Role of Qualia - Lee Smolin - 11/22/23
37:19 Christof Koch asks why Lee thinks of Qualia as one-dimensional. Koch's objection that colour is clearly three-dimensional, talking about color spaces, which are not actually what we experience, so they are not qualia! Similarly the multi-dimensional sense of taste and smell we have: that is again abstraction: ask a baby to tell you whether this particular brand of Scotch whisky is smokier than it is peaty and see what sort of answer you get! These things are learned. These "dimensions" are essentially linguistic, cultural constructions, not immediate senses! Koch should definitely meditate more! See also this post of mine: Psychophysics.
45:35 How to test this experimentally? That's done every time a new experiment is done, isn't it? Every time a new set of boundary conditions gives rise to a new effect that is reproducible in other experiments carried out by other people. The experimental result is a conscious event, new the first time it occurs, and part of the Universe whenever it is repeated. Maybe I'm trivialising the idea, but it doesn't seem trivial to me. I thought that's why people do experiments.
For more on Varieties, see Math-Life Balance - Algebraic K-Theory.
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Curt just clipped this interview with Julian Barbour a week or so ago:
See my comment:
7:50 That is kind of obvious, isn't it? Any physical effect is produced by some specific type of experimental setup which determines the boundary conditions in which the Lagrangian gives the path of stationary action. So the Universal law (or unifying theory) of Lagrangian mechanics is that universal physical laws are all those things which happen just because there is no particular reason why anything else should happen. For example, when you drop a ball onto the surface of the earth it follows the path where the kinetic energy minus the potential energy is stationary. So if you drop the ball through some viscous fluid then that viscosity is the reason why it doesn't follow the path of stationary action, because it loses energy to the medium. Similarly, if you catch the ball in mid flight, stop it and then let it go again, it doesn't follow the same trajectory because you interfered with it. And what we call an objective physical effect is one that is independent of the coordinate systems used to describe the system. Independent in the sense that whatever two experiments you have, in whatever coordinate systems and whatever laboratory you happen to be in, will have effects which are in a correspondence according the functions which translate back and forth between those different coordinate systems and laboratory conditions. And we generally try, following Ernst Mach, to choose the simplest possible description, because we want the effect to be as general as possible. Newton effectively did that, and found that all he needed was the mass and acceleration of the particle to predict its motion, so that was the simplest description, and it works in all sorts of situation, even fluid mechanics where the Navier Stokes equations are basically just Newton's applied to a fluid. The point Julian made about the photographic evidence for Quantum Mechanics is related: you cannot compare effects like interference of photons without collecting together a large sample of photons hitting the screen, otherwise there is no pattern. One photon does not make an interference pattern! Neither do two photons, because they could be anywhere on the screen (because of the finite resolution of the 'detectors' on the screen, whether those are photomultiplier tubes, or cells in a CCD imaging chip or crystals of silver nitrate on a photographic emulsion. So you always need a composite image to collect the statistics and it is those statistics that are predicted by the Schrödinger equation, together with the boundary conditions for the experiment.
8:10 On God and variety: see Aristotle on God.
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Laura hiking in Bethlehem, NH
and Acadia National Park, MN
part II
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Darz Rojaz on tele-qualia:
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Victoria has a ten-minute meditation lesson she's sharing with the world. She's in a funny mood:
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Angela is still trying to exorcise Richard Feynman from her shoe closed, ... She needs help! Turns out Richard Feynman hasn't even written more books than I have! See Angela's Richard Feynman Video. She paid $587 for all these books Richard Feynman didn't write, and that was on Thrift Books!
16:45 She thinks Gell-Mann's The Quark and the Jaguar is long and boring and not worth reading! Here's Gell-Mann talking about it for an hour and a half, ...
I think I'm going to start a new YouTube channel, ...
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Arunima Ray talking about her career in low-dimensional topology. There's a lovely story about how she proved a theorem!
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Darz Rojas waxing philosophical, ...
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Popinat asking deep questions too. This is hilarious!
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Emily Riehl (who got a bad dose of the British disease, sadly) on the Yoneda Lemma with an example from linear algebra. See the comment about vecor spaces in Julian Barbour - Complexity as Time.
From the preface to Emily Riehl's book Category Theory in Context:
Atiyah described mathematics as the “science of analogy.” In this vein, the purview of category theory is mathematical analogy. Category theory provides a cross-disciplinary language for mathematics designed to delineate general phenomena, which enables the transfer of ideas from one area of study to another. The category-theoretic perspective can function as a simplifying abstraction, isolating propositions that hold for formal reasons from those whose proofs require techniques particular to a given mathematical discipline.
A subtle shift in perspective enables mathematical content to be described in language that is relatively indifferent to the variety of objects being considered. Rather than characterize the objects directly, the categorical approach emphasizes the transformations between objects of the same general type. A fundamental lemma in category theory implies that any mathematical object can be characterized by its universal property—loosely by a representation of the morphisms to or from other objects of a similar form. For example, tensor products, “free” constructions, and localizations are characterized by universal properties in appropriate categories, or mathematical contexts. A universal property typically expresses one of the mathematical roles played by the object in question. For instance, one universal property associated to the unit interval identifies self-homeomorphisms of this space with re-parameterizations of paths. Another highlights the operation of gluing two intervals end to end to obtain a new interval, the construction used to define composition of paths
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Daniel Tubbenhauer talking about the Yoneda Lemma as being like shooting at things to find out their structure:
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Laura in Salem and Castle Craig CT:
She started her two-month long road trip in California!
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Elle Cordova looking for a date with a typeface. Or maybe I'm reading too much between the double-spacing, ...
A TILF (or Transforaminal Interbody Lumbar Fusion) is a surgical technique for emergency treatment of Cauda equina syndrome, which is a medical emergency ... It causes back pain, weakness and incontinence.
Email her agent if you're interested: https://www.ellecordova.com/
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Anton has some data for anyone who thinks they can describe electromagnetic forces in terms of curved space-time. I can' t get my head around that idea at all. See Dynamo Theory:
Dynamo theory describes the process through which a rotating, convecting, and electrically conducting fluid acts to maintain a magnetic field. This theory is used to explain the presence of anomalously long-lived magnetic fields in astrophysical bodies.
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This helps a bit: Lee Smolin on the difference between Quantum physics and General Relativity.
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Sabine Hossenfelder on how AI could do a better job of this blog than I do:
Curt Jaimungal has put all his Theories of Everything interviews into an AI that you can talk to, as long you're not trying to use it from a phone: https://toeai.curtjaimungal.org/.
I asked: "How does loop quantum gravity unify gravitational and electromagnetic fields?"
It said:
According to Carlo Rovelli, loop quantum gravity asserts that space time is a quantum entity and that gravity is an emergent property of quantum dynamics. It's a leading contender for a theory that merges general relativity with quantum physics—a long-standing problem in theoretical physics.
Rovelli's theory holds that the geometry of space is indeterminate, with the universe simultaneously exhibiting numerous possible geometries—a concept known as quantum superposition. The smallest units of space in this theory are the Planck length or Planck area.
Loop quantum gravity is not itself a unification of all forces, nor a final theory of everything; it's a more humble approach focusing on the gravitational interaction.
Would you like to know what challenges physicists face in unifying general relativity and quantum mechanics?
Sabine also did another video about Dark Matter:
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My AI is getting bored of listening to the news:
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Darz Rojas on Shoveling Snow, Unpacking and Motivation.
I make YouTube videos when I see animals, or feel I'm not getting through to people, or when I go somewhere different. It's like a substitute for a social life I suppose.
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Here's Laura standing where the Statue of Liberty's brain should be, ...
... and on Ellis Island:
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Dr Fatima on the Challenger O-ring Failure analysis graphs that NASA engineers actually prepared before the launch "to try to persuade the administration to postpone the launch":
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Darz Rojas with an idea. Someone should have patented this one!
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I have also been listening to Angela Collier on more or less confused masses:
Lev Okus's paper on mass: http://www.itep.ru/science/doctors/okun/publishing_eng/em_3.pdf and the Wikipedia page on the Energy-momentum relation.
I am watching this as a prerequisite to trying to find out where Louis de Broglie got the idea of matter waves. And all this is to try to get an idea of the physical significance of the parameter t in the solutions to the Schrödinger Wave Equation.
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Nick Cave & The Bad Seeds - The Making of Wild God (Full Movie)
I think Megan Cullen is going to go far, if she hasn't already done so! Yes, she has: https://megancullenphoto.com/Information.
Further Rescue Attempt became Final Rescue Attempt:
That song reminds me of a time I was sitting outside a pharmacy on Calle Juan Bautista in Cochabamba and I thought I saw Patty turn up at Jaguar House with a whole entourage in tow, ...
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Lina Sleibi and Ooberfuse - Believe in Love
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I just went to see All We Imagine as Light and it was really beautiful. Whilst I was in the cinema these two videos showed up:
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And then I hiked down to a coalmine in West Virginia with Laura.
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... and I am saving Toby's "How to put down your phone and get something done" video for tomorrow! It was good. I think she was trying to stop me from seeing her YouTube shorts, especially this one:
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MBARI - Beautiful Creatures Under the Sea
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David Gilmour's YouTube Dulcimer Christmas Card:
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Noah Explains Physics - Dirac's Belt Trick, Topology and Spin 1/2 Particles
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Joel David Hamkins on Geometry and Proof:
A significant moment: what is the connection with logic and physics?
1:05:55 Because the spheres intersect.
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Holistic protein structures have been known for decades, ...
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Why, Mr Anderson? Why do you do it?
Maybe it's just that he's bored?
What are Matroids, really? See Daniel Tubbenhauer Explaining Matroids Again.
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If you want, you can buy yourself a new laptop and read this pathetic review of her book My Work in The Guardian, and then donate some money to them because "This is what they're up against, ..." Then you can get a copy of The Employees from Amazon!
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