sethoflagos

That scenario was correctly introduced by @studiot as an example of long term low entropy structure in the universe. Entropy is central to the OP, so one may wonder whether a lossless classical n-body system has any relevance. It appears to be a thermodynamic dead end. What I'm attempting to do is argue for the thermodynamic relevance not only of the path toward the minimum free energy classical ideal, but also the relevance of such structures as 'eternal' reservoirs of 'negentropy' (despite an aversion to that term). A parallel, but very much faster evolutionary path has been made for the condensation of protons from a primordial quark gluon plasma: another low entropy, minimum free energy structure created with a truly enormous generation of thermal energy to maintain consistency with the 2nd Law. CERN may well suggest that breaking protons is commonplace, if one turns a blind eye to their need to create energy densities coequal to those of the early universe in order to achieve it. Taken together the 1st and 2nd Laws suggest that one cannot reverse the arrow of time in this way on a cosmological scale as proton decay implies. I'd sooner buy into astrology. Quite. +1

Really ? Is that the lowest energy state ? Really. All particles would be free to diffuse to any location within a planet of uniform composition. And no. The lowest energy state would see the planet in an onion structure of concentric shells of pure components sorted by density. But this doesn't happen either. (Glossing over issues rnvolving chemical potential: reaction, phase change, etc.) The direction of planetary evolution is towards a state of lowest free energy, which is a hybrid of these two forces (H = U - TS) The U component drives differentiation of the planetary interior into shells of differing densities; the S component ensures that some degree of mixing always remains, especially among components of similar density. Well, you've obliged me to think through in detail something that I'd only a vague hand-wavy picture of before, so thanks for that. ...where TdS again characterises the minimum heat shed by the system due to tidal forces as the two bodies exchange angular momentum on their journey to becoming a fully tidally locked single structure. Wouldn't this now become effectively a single isolated body?

Yup, currently inaccessible states need a free energy boost to access them. No disagreement here. Now how about properly addressing my comments on structure? Or am I just wasting my time?

A 'maximal entropy' planet Earth would have no atmosphere-ocean-crust-mantle-core structure. It would be all mixed up into a homogenous blob (which is roughly how it started out). Clearly, this was unstable as the denser components had way too much gravitational potential energy for underlying lower density material to support and they sank towards the centre despite the long-term reduction in (ISOTHERMAL) entropy that implied. The 2nd Law wasn't broken:: the large negative dU component of Free Energy was released as more than sufficient entropy increasing heat to offset the entropy reducing TdS drop in thermodynamically available states. But ultimately that heat, and its associated entropy, would be radiated off into space. Far from evolving into an unstructured body of maximal entropy, it evolves toward a highly structured body of minimal free energy. (Since you're a physicist, I'm using Helmholtz Free Energy here 😉) Similarly, life uses the surplus free energy of other 1st Law energy sources (sunlight, chemical energy) to convert high entropy water and carbon dioxide into highly structured lower entropy cells and multicellular bodies. I use the word 'structure' here as a preferred alternative to 'negentropy' or 'complexity', both of which I think are easily misunderstood. But they are effectively synonyms for reservoirs of APPARENTLY negative entropy. I say 'apparently' since the negative residue is more than balanced by a corresponding radiation of heat from the system. Clearly these must be accounted for in any discussion of cosmological entropy budgets. Proton decay with a 1034 year half-life would clearly obliterate all familiar structures within 1035 years. I half suspect that the concept was invented by some physicist who couldn't be bothered to account for cosmological structures in his calculations. Let him demonstrate an unambiguous and spontaneous proton decay, and I might begin to take the possibility seriously. Until then, I shall remain commitedly atheist about it.

Wherever you feel the urge to use the word 'randomness' in relation to entropy, try replacing it with 'diversity': diversity of position; diversity of momentum; diversity of type; and you will be much closer. The 'diversity of type' (or 'entropy of mixing') is a much underappreciated aspect as it permits the creation of novel structures due to the low entropy ordering of the structure being offset by its high entropy contribution to diversity. Hence stars can ultimately produce the heavier elements; which beget life; which begets the broken transistor radios and other miscellaneous items of space junk that continue to populate a cold universe at the end of time. @MigL can possibly explain how all this structure can be eroded away in the apparent absence of the necessary activation energy - though I can't see it.

Emily's hooked on top Tibetan's saucy diary reveal on her new app. Pin "Ruth Social", Administrator! Pro tarts in "I'm Dalai" cosh Turnip!

Consider why motorists are so heavily shielded from charges of recklessness simply for bringing an inherently dangerous piece of machinery into an environment shared by others. The origin of 'jaywalking' is instructive: If a man takes his imported pet leopard for walks down the village street, and every so often it bites a lump out of a passing yokel, who is morally responsible for this? The leopard? The yokel? Pray explain why there should be any difference regarding machinery whether AI controlled or not. Indeed this argument seems to render the AI factor irrelevant.

A topical one courtesy of Private Eye

Such a lofty idea it's gone and flown right over my head (was it a bird? was it a plane? ....)

Good points. Reading between the lines, different interest groups are all pulling in different directions, competing for limited governmental attention and development budgets. What's clearly lacking at national levels globally is holistic long-term power supply planning covering: Projected regional power demand Capacity and distribution of base load generation. Capacity and distribution of hot-standby generation. Capacity and distribution of cold standby generation. Capacity and distribution of deep power storage units. Transmission capacity. Stable environmental impact criteria. Stable and flexible grid supply-demand management. Grid voltage and synchronisation management. Stable grid frequency control Power factor control. Rigorous transient and fault protection. Progressive stable and fair power pricing policy (both internal and external) Progressive stable and holistic investment policy Rational accommodation of technological advances. Failure to address any one of these appropriately will adversely impact grid performance as a whole. The free market will always cherry pick the fastest ROI, neglecting the rest, so the central dilemma is how to achieve all of the above through stable, integrated state-level control for the next 50 years. (Where's Stalin when you need him!)

For the same unit power output per unit volume of fluid, a denser fluid needs: less elevation difference; shorter pipe runs; lower fluid velocity. Without knowing the exact nature of the fluid, it's impossible to say whether losses would rise or fall. For some dense fluids (e.g. mercury) I imagine that losses could fall significantly. There is potential to increase power output per unit volume of fluid, but now losses would rise in rough proportion (also to square of velocity) though this does seem to imply that efficiency doen't take a serious hit. Key algebra is h = v2/2g = 'velocity head'

The main advantage IS being able (potentially) to locate high capacity gravity storage in areas of lower relief, perhaps locating them closer to regions of high demand cutting distribution losses. A secondary benefit maybe the lower liquid head to volume flow ratio may better facilitate the use of mixed flow (Francis vane type) pumps and turbines which may help hydraulic efficiency. No mention of the high rates of mechanical wear typically associated with slurries though.

The thermodynamics of a 'photon gas' is well established and quite real. Very similar to the thermodynamics of a molecular gas, but slightly different equations: (there is no conservation of photons etc.) On second thoughts, that's not what you're saying is it. You're referring to that unheard falling tree in a forest malarkey. Never really gone in for that viewpoint. Bit too solipsistic for my taste.

They will suffer an ''absence of heat" death. No more stars (or radioactivity etc.) to keep local temperatures much above absolute zero. Chemistry ceases to be a thing. Or at least chemical reactions grind to a halt. No food; no respiration; no metabolism. Periodically launch probes into deep space and carefully watch their red shift? Long term experiment, but what else are you going to do for a googol-year?

Unless you're suggesting that growth of the scale factor will decelerate to zero, can there ever be a maximal entropy? (IIRC, AOTBE, entropy grows proportionally to ln a) Ultimately, matter and energy may become so thinly spread out that particle interactions rarely occur, and each particle tends towards its own isolated little ground-state universe of entropy zero (in its own frame of reference). But then, many if not most of these will be photons which don''t experience time anyway. As for the leptons, while they are able to oscillate between their various flavours/states, they must still be little clocks ticking away for eternity, aren''t they? Which suggests that time will at least continue somewhere. Even when their nearest neighbours have been accelerated away to such an extent that their light cones no longer intersect. It all begins to sound a bit Hilbert's Hotelish, but I've yet to see anything paradoxical in an asymptotic approach to zero local entropy density at infinite time/global entropy. Not sure that 'equilibrium' has any meaning at such infinitessimally low densitities. No collisions: no equilibrium.

We're in the Lounge! (... and just how did you assess a 50 minute clip within 20 minutes of me posting it? Another mindless kneejerk reaction?)

On 4th June, the European Parliament replaced Google with Qwant and five days later, Europe released a sovereign alternative to Microsoft Office.

Ever wondered WHY you have such a negative instinct towards intelligence? I've linked a Youtube video that offers some explanation. I think it goes a bit over the top in places, but that's Australians for you. I know you won't actually watch it, and even if you did, you wouldn't be able to let yourself learn anything positive from it... https://www.youtube.com/watch?v=j9MubNsh3rs

I've just hopped onto chess.com to check the aforementioned 'one line that I don't play' (1Nf3 e5 2 c4...) and have confirmed without a shadow of a doubt that it is absolute poop. Not that it leaves white in a bad position, far from it, but 2 Nxe5 is simply up a free pawn with zero compensation for black. A no-brainer if ever there was one. Situation normal is reconfirmed. ChatGPT copies where it can and guesses where it can't. And now I'm pretty sure it copies extensively from the chess.com database (where a good few hundred of my games are stored - confirmation bias or what!)

I pretty much agree with all of your post above. It prompted me to repeat a question to ChatGPT that I have previously asked earlier LLM versions over the last few years, that, at first, drew hopelessly inept responses. Tonight I got: There's not a word here I can find fault with. In fact, I felt driven to ask it a far deeper follow up question about about a relatively obscure opening system that I've fifty years pretty solid experience of playing (against both human and silicon) If I knew the references the model used to glean this, I would buy those books without hesitation. (I was under the impression I'd read them all - I clearly haven't) To top it all, this is what I got from the recommended follow-up: With the exception of one line that I don't play (until now, perhaps) this IS move by move, the opening strategy I've developed by trial and error over the last 30 years. I play a fair bit of online chess and never encountered anyone (within my recollection) who's played this system against me. It is rare, certainly at the modest level I regularly play in. I'm actually quite gobsmacked (technical term) by this. At least, it my lowly ratings status doesn't seem to be down to a poor choice of openings strategy as white.

Twi is an indigenous lingua franca used across much of Ghana. 'Falala' as both concept and given name has been widely exported, even unto Yorubaland. ...and osteopaenia 😉. Palindromicity, is enough of a constraint, I think. However, too much linguistic diversity may leave Emily confused as to just how many amphibian poachers were detained in the swamps of East Netherlands region: Twente nein Eft Act arrests - err at Cat Fen i.e. net newt. ChatGPT almost gets this except it has to be told that dialect variant 'eft' is the OE root of 'newt' (via 'an eft'/'a neft')

To pet animal as I see, bro, fava for bees is a laminate pot. (actually wanted to use 'Falala' - being born into abundance - rather than 'fava', but I guess you have a rule against using Twi 🙀) Could I slip it in as a misspelling of Valhalla? That would work (frawd!!!).

So was I: the dwarf planet, Eris, and its moon, Dysnomia. And then there is the subtext of their roles in Greek Mythology: Eris (strife) and Dysnomia (lawlessness, bad government). Too esoteric?

Well you gave me the Eris-Dysnomia system, leading inexorably to Roy Batty's Which became a 'pastel battle moot' (OE: meeting), with C-beams aimed at Syd. Naturally, my own personal involvement would limited to melting the tablet sap necessary to fuel the attack ships. Makes (satisfyingly surreal if not absurd) sense to me. Don't see what else I could do with it really given your subject matter and your constraints 🥺 Adhering to the mandatory rules of grammar, punctuation, and form clearly parallel the time reversible Dirac formalism. The rest is absurd. Just run with it.

True, but there are a class of activities that centre on exploring complex structures built from sets of fundamental units that seem to share much common mental real estate: Word games (the alphabet) Chess (the pieces) Music (the harmonic series) Bridge (deck of cards) Maths (the integers) Particle Physics (the standard model) Chemistry (the elements) Cooking (basic ingredients) Computing (the set of logical operations) Minecraft (the building blocks) If someone is skilled at any one of these, hearsay has it that they are at least likely to have an aptitude for some of the others. The symmetries inherent in one tend to repeat in odd places among the others with only minor tweaks. Does the sound and spelling of a phoneme have a direct causal relationship with the wave/particle duality of a photon? Probably not, but there is a shared symmetry in there that just helps gain a foothold...