sethoflagos

So science is of no assistance in assessing the potential benefits of reciprocity? Tough on those who were born with a low empathy level and are denied the means to work out that there may be some value in faking it now and then.

She doesn't. At no point does she state or even imply that: On the contrary, the entropy of a system may be defined absolutely by reference to the 3rd Law. And it is not 'all possible microstates of ðe system', it is 'all possible microstates of ðe applicable macrostate'. To understand this distinction, you need to understand the concept of microstate accessibility as referenced in the ergodic hypothesis. It's important. However, what she does say at ~9:40 is: This is true, but rather than follow this logic as I might to demonstate that there is no real conflict with the existence of domains of order within a closed system at thermodynamic equilibrium (for instance, the indefinite stability of an ice phase in an isolated system of water at its triple point) she continues with the following: Thermodynamic microstates are a snapshot of a system in a volume of space and have zero entropy; macrostates refer to the properties of that system observable in a volume of space-time. It is not 'still the same microstate': it is the ergodic progression through various microstates of different macrostates(!) Dr Hossenfelder seems to have confused the evolution of an out-of-equilibrium thermodynamic system stepwise through various macrostates towards a condition of thermodynamic equibrium (which is the process she describes) with the way in which a single quantum state may evolve. I suspect that she is encountering problems in attempting to square her curious views on determinism with the 2nd Law. Don't you mean “microstates wið respect to P"? No. All microstates have zero entropy. Entropy is an emergent property of all available microstates taken in combination. Hence a macrostate has a uniquely defined entropy even if some of the constituent microstates seem to exhibit spooky patterns.

Whatever that means. Forgive me but it comes over as avoiding the question.

First port of call would be a windscreen or headlight wiper mechanism from a car scrapyard. The cheap ones, not the ones with reversible motors. You might get the required sweep and cycle time by tinkering with the linkage, but incorporating a reducing gear might be more productive.

I was hoping to keep this general and not get sidetracked into the details of specific cases. Maybe the superposition of free neutron and its decay products. Obviously both states have a particular defined and equal total energy as isolated states in our physical universe. However, in superposition, these states do not exist as the simple sum which amongst other things would double the total energy content. Does the superposition actually have a concrete form within our universe or does it imply some degree of real existence in a space outside of it as does its abstract complex mathematical description? It's that abstract form of existence that I'm asking about. Not massless neutrons. As in my above response. It's the unmeasurable nature of the superposition - the coexistence of multiple versions of a single system - that's of interest to me here. @studiot, @Genady & @swansont I can understand the attraction of dogpiling onto point 6) Please confirm your position on points 3) & 4) to help me understand where we have parted in the logical progression.

Wouldn't that be a physical state? The mathematical description of it would be an abstraction without substance,

Went back to the start of the thread to see how far I could follow it before I got lost. The following list a a sequence of what appear to be logical inferences that spring to me from the above post. At which step does the logic break down? 1) The evolution of the individual quantum states in a superposition are accurately described by an appropriate wave equation such as (eg for Dirac fermions) the Dirac equation. 2) Although the Dirac equation maps onto our R3+1 spacetime, it is expressed in terms of a 4 dimensional complex vector space that is not defined within our R3+1 spacetime. 3) It is unclear whether or not quantum states in superposition have an individual material presence, but either way, they appear to be unmeasurable while they remain in superposition. 4) If indeed these individual quantum states have no concrete, physical existence within R3+1, then they appear to be only abstract objects existing outside of R3+1. 5) Side note: Point 4) is consistent with the possible emergence of our R3+1 universe from an initial quantum state that was not a part of our R3+1 universe. 6) As an abstract form, a quantum state need have no energy content, and therefore may coexist with an infinite multiplicity of alternate quantum states without conflict with the 1st Law of Thermodynamics. 7) As a uniquely defined state, it has a single permutation and therefore zero entropy. It may therefore coexist with an infinite multiplicity of (independent, non-interacting) alternate quantum states without conflict with the 2nd Law of Thermodynamics. 😎 Side note: if a quantum state in superposition did have a concrete physical presence in R3+1, then points 6) & 7) become difficult to explain away. 9) As any specific solution to the Dirac equation is bidirectional in time (explicitly includes an advanced wave acting on the state in the time reversed direction), using point 7), no information is exchanged in this process and properties apparently exhibiting computation of eg Feynmann's 'sum over histories' concept may evolve without conflict with the principle of Causality. 10) It appears that an unambiguous measurement within our R3+1 universe requires an action originating from somewhere external to it. 11) It is really difficult to refer to a point 😎 on this site.

Are you looking to operate another mechanism with it? What's the desired amplitude, cycle period and torque? How much space is avaiable? Can you be more specific about 'corrosive'?

Cave troglodytam. ... or was that Diogenes.

Chaos is imho an unhelpful word. As mentioned above I find that replacing it with 'diversity' a great help. We then see complex systems featuring diverse inhomogenies of structure, energy and mass density, chemistry etc., each of which are quantifiable in terms of entropy. And a little mathematical experimenting with the 2nd Law inequality shows that entropy scales with the logarithm of each of its system state variables (volume, temperature etc) Boltzmann's (actually Planck's) famous formula for entropy S= k ln W where W is the number of microstates (possible permutations of location, momentum, particle type etc) encapsulate this non-linear logarithmic characteristic to all measures of diversity in a complex system. It's really rather fundamental and built in to macroscopic systems. Of course a single isolated particle (a normal helium atom to keep things simple) taken in its own frame of reference is completely and uniquely identified. There is only one permutation. W = 1, ln W = 0 therefore S = 0. Entropy does not exist at the level of an isolated particle. It is purely a property of a multiplicity of particles. It is an emergent property that does not exist at the level of its constituent parts. This is really the basis of most non-linear behaviour in complex physical systems such as weather. Another time we can extend the discussion to information content and see that this reasoning governs much of our lives.

So causal influences are simply a dichotomy of the determined and the random? Are these the only possibilities? Why do you omit those arising from the infintely larger sphere of the abstract? Under conditions of physical duress, I might turn my mind to imagining a full-blooded chorus of Ritt der Walküren to summon power and fortitude from its driving ferocity. Where does all this magnificent sound come from? Do I have a high fidelity recording somehow etched into my brain? What if I change the tempo a little - or a lot? What if I decide to try out Kirsten Flagstad as Brünnhilde in place of Birgit Nilsson. I've only heard snippets of Flagstad's Brünnhilde and that was in Götterdämmerung but I can imagine her in Die Walküre, her subtly different timbre and undeniable glamour bringing an altogether different feel to the staging? What if I imagine the all-important bass trombone is thundering a little on the flat side... or god forbid! sharp!? Each change will impact my mood and my actions on my surroundings (or at least my long-suffering wife). Nothing of this is 'random' according to my understanding of the word. Nor can it be written into the entropy of any historical arrangement of material particles and be thus determined. And yet the sight, sound, scent, taste and touch of that conscious experience have existed since at least the dawn of time as a distinct potential in the abstract. Every bit as real as the number seven. So when I decide seven is greater than six and act accordingly, it's not a random decision; it isn't determined (though it may be expressed) by my environment; it just is. So I affirm that fact with my will. If and when I'm in the mood to do so.

Indifferent to a stationary human though comforted by a stationary car. Cautious of a nearby moving human yet terrified of a distant moving car (in a 20 mph zone) Non-linear responses. Have we got around to tipping points yet? I've spent quite a lot of time on my birdwatching treks watching the reactions of various wild beasts to my presence and your summary is a good generalisation. Except when an elephant waves its ears and its me who has to do the running. On second thoughts, it's the same deal.

Superstitious? Me? Your post strikes me as a long-winded, pretentious version of "I don't know but trust me, I'm a doctor" No useful content like 'at least vaping exposes you to nicotine only'. Please feel free to relieve your boredom by other means.

The cat's clear overreaction could well suggest some flight response to a predator. Perhaps the sound of the engine stirs some ancient memory of a leopard's roar. I'll have to investigate their response to a car being started.

I was outside having a smoke recently and whiled away the time watching a cat cautiously cross the pavement a couple of metres ahead of me seemingly intent on crossing the road. The view down the road was obstructed by a parked van but from my vantage point I could see a pedestrian approaching on the far side pavement. The cat froze in its tracks. At first I thought that this was due to seeing the pedestrian. However, a car suddenly came into view and the cat bolted to hide underneath another vehicle parked off the road beside me. After it had passed, the cat emerged once more and approached the road only to see a vehicle coming from the opposite direction whereupon it bolted yet again to its place of safe refuge. Its third attempt at crossing the road passed uneventfully. The cat clearly was a little cautious of nearby humans. It seemed to have no fear at all of stationary vehicles, indeed seeing them as places of safety, Yet it fled in absolute terror at the sight of a moving vehicle. In my experience, cats tend not to survive any degree of impact with the latter, so I was left wondering what the learning process might be.

I read this and thought that you have just outlined the book definition of weak emergence. This reference - SUPERVENIENCE, PHYSICALISM AND EMERGENCE - is a little longer than yours but for me, it pulls together many loose strands currently floating around the site. The fireworks start when we get on to strong emergence. Fasten your metaphysical safety belts.

My wife is of an evangelical persuasion. But her politics are social democrat so we get on fine providing we avoid talking about evolution. Coexistence at the individual level need not be problematic. It's at the institutional level where the real damage is done. And the 28th vote was the first 'don't know'. That's interesting in itself.

Okay, but I'm going to have to unpick your post in reverse order since it's the baggage trailing in the wake that I take issues with. Can I assume here that your 'libertarian' is the selfish and impulsive spoilt brat of right-libertarianism as understood in American circles? It's an important point since I'm drawn to a form of libertarianism based on the utilitarian principles of William Godwin. Here, while acknowledging both the validity and value of the base impulses, they are exercised within the framework of a good, solid code of ethics. For me, Aristotle's Golden Mean plus a measure of stoicism works (eg 'make a friend of hunger' counts as sound medical advice). I try not to take offence when you condemn libertarian values as 'absurd', but I do speak English rather than American. Your point gets lost in translation. You oblige me to read The Libet experiment and its implications for conscious will, to understand some guy's work that no-one else can reduplicate. My impression is that our potential responses arrive in waves starting with the base impulses, with more nuanced influences following on and consciousness emerging somewhere during the process to play a supervisory role in making the choice. Sometimes just to say 'Oops! Sorry' when the action came prematurely. Does this script not fit the style of the movie? Perhaps. Or perhaps it's the lack of consistency in the degree of determinism necessary in defining 'will'. One sentence linking at least five distinct concepts all subject to diverse interpretation. Easy as pie! We differ only on the role of determinism, I think. That's our main outstanding issue.

I fully take on your point of not throwing out the baby with the bathwater and agree wholeheartedly. However, while monolithic organisations are able to claim ownership and flag wave these beneficial ethics as symbols of their fitness to hold sway, rather than see much in way of benefit we tend to get lumbered with all the detestable baggage following on in the wake.

Bogus positions of undeserved influence and authority will always attract the walking dog turds of our communities.

The goal may indeed be very distant; possibly unattainable for many generations to come. But is that any reasonable excuse to stay clinging on to the old shackles of the distant past that have clearly denied so many the opportunity to realise their full potential for so long?

Thank you for this. I believe that there is a general consensus that entropy is Lorentz invariant and much of what you say seems to follow on from this sensibly enough. Minor-ish exceptions: For 1) I'd say that it may operate equally in both the abstract and concrete realms as one might expect if it were one of the most fundamental of laws (ie holds for all physically possible universes) as some suspect. 5) For similar reasons, I'd be tempted to consider substituting 'non-physical' for 'teleological'. If I understand you correctly, the time reversed transitions appear to be goal-driven (teleological) towards simply restoring the initial state in the absence of any convincing causal mechanism to drive it. A bit off-topic perhaps but appreciated here anyway.

He gained his Nobel prize for his work in irreversible thermodynamic processes during my first year chemical engineering course so a few of us dipped into his work out of interest (long before the pop-sci chaos carnival kicked off): Rather than his self-organisation stuff(which I found hard to grasp) my main take away at the time can be summarised in this little snippet from his Wikipedia page: Maybe that helps frame some of my earlier posts here and elsewhere. I'm averse to hard determinism and not just for religious reasons. If we loosen the thrall of determinism a little, then I can nod my head in agreement. Catalytic Synthesis of Polyribonucleic Acid on Prebiotic Rock Glasses has already got us up to sequences of several hundred nucleotides with no resort to 'quantum woo'. It isn't so much a question of increasing the number of physical interactions as such. More maybe assembling some virtual low probability microstate within a superposition to which a phenomenon like tunnelling can help bypass the sometimes significant energy barriers to gain access. (Woo alert!) To get around ergodicity issues etc. A classical, determinist model may be overly pessimistic by orders of magnitude if this isn't merely a pipedream. Precisely. So happy you butted in there 😁

Please feel free to butt in! I was hoping someone would raise the topic of ergodicity as it is relevant, Thermodynamic equilibrium is often presented as a dull, featureless system state, but it seems quite the opposite to me. If it is interpreted as the condition of maximum quantum entanglement of its constituent parts, each of those linkages existing as superpositions all of their possible outcome states, then in at least some limited sense, thermodynamic equilibrium can be seen as a superposition of all possible arrangements of its constituent parts consistent with its geometry, chemical makeup and total energy content. That is, that all structures that can possibly exist within that state do so simultaneously at least within the non-material abstractions of the mathematical space wherein the superpositions reside prior to 'being looked at' (ahem). Ergodicity (the limitation that in the concrete, individual microstates can only be accessed by stepwise progression from a neighbour) places limits on this picture, but I hope there is some truth in it as it helps me get my head around quite a few practical situations that are otherwise difficult to comprehend. For instance, abiogenesis becomes considerably less problematic if all necessary component building blocks continuously coexist at least to some degree when conditions render it a non-zero possibility, even if that space is temporarily abstract rather than concrete.

From the Lorentz interpretion of chaos I mentioned above, it is possible for some number of associated parameters to evolve under the action of linear operations in entirely deterministic fashion and yet produce significantly unpredictable futures such as the weather phenomena you describe. The (local) universe is not big enough to define general numbers with suffient absolute precision to prevent this from being the case. However, it is not the full story. For example, it seems implausible for the above mechanism to produce all emergent properties not explicitly existing in the fundamental low level interactions. Yet, everyday experience tells us that we are likely to hear dull music in supermarkets.