TheVat Posted December 9, 2023 Posted December 9, 2023 15 minutes ago, sethoflagos said: 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. A liitle trouble following here. Does this relate to Prigogine and self-organizing systems? So rather than a world where pure classical chemistry prevailed, fully deterministic, and maybe the complex chemistry of life would not have developed, we needed the unpredictable but still deterministic chaotic systems of quantum superpositions of all possible arrangements? Would this increase the chances of ACGT bits colliding and starting RNA strands? The primordial pond tends toward states that are more organized?
joigus Posted December 9, 2023 Posted December 9, 2023 7 minutes ago, TheVat said: A liitle trouble following here. Does this relate to Prigogine and self-organizing systems? I think what Seth means is QM allows for the final state in a complex multi-step reaction being "there" as a potentiality, so to speak, in the form of a quantum amplitude driving the process. Classical thinking, OTOH, seems to require first one step, then another, then another. Something like that? 1
sethoflagos Posted December 9, 2023 Posted December 9, 2023 (edited) 51 minutes ago, TheVat said: Does this relate to Prigogine and self-organizing systems? 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: Quote In deterministic physics, all processes are time-reversible, meaning that they can proceed backward as well as forward through time. As Prigogine explains, determinism is fundamentally a denial of the arrow of time. With no arrow of time, there is no longer a privileged moment known as the "present," which follows a determined "past" and precedes an undetermined "future." All of time is simply given, with the future as determined or as undetermined as the past. With irreversibility, the arrow of time is reintroduced to physics. Prigogine notes numerous examples of irreversibility, including diffusion, radioactive decay, solar radiation, weather and the emergence and evolution of life. Like weather systems, organisms are unstable systems existing far from thermodynamic equilibrium. Instability resists standard deterministic explanation. Instead, due to sensitivity to initial conditions, unstable systems can only be explained statistically, that is, in terms of probability. Maybe that helps frame some of my earlier posts here and elsewhere. I'm averse to hard determinism and not just for religious reasons. 51 minutes ago, TheVat said: So rather than a world where pure classical chemistry prevailed, fully deterministic, and maybe the complex chemistry of life would not have developed, we needed the unpredictable but still deterministic chaotic systems of quantum superpositions of all possible arrangements? If we loosen the thrall of determinism a little, then I can nod my head in agreement. 51 minutes ago, TheVat said: Would this increase the chances of ACGT bits colliding and starting RNA strands? The primordial pond tends toward states that are more organized? 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. 34 minutes ago, joigus said: I think what Seth means is QM allows for the final state in a complex multi-step reaction being "there" as a potentiality, so to speak, in the form of a quantum amplitude driving the process. Classical thinking, OTOH, seems to require first one step, then another, then another. Something like that? Precisely. So happy you butted in there 😁 Edited December 9, 2023 by sethoflagos typo 1
KJW Posted December 9, 2023 Posted December 9, 2023 19 hours ago, joigus said: Bell's theorem is about whatever variables that can take on definite values at the same time. As the theoretical structure of QM forbids non-commuting operators to take on a definite value at the same time, there's the connection. Thanks. However, shortly after I posted my question, I realised that you were right, at least for the original Aspect experiment involving polarisation of photons, with non-commutativity having an essential role in the experiment.
KJW Posted December 9, 2023 Posted December 9, 2023 Quote In deterministic physics, all processes are time-reversible, meaning that they can proceed backward as well as forward through time. As Prigogine explains, determinism is fundamentally a denial of the arrow of time. With no arrow of time, there is no longer a privileged moment known as the "present," which follows a determined "past" and precedes an undetermined "future." All of time is simply given, with the future as determined or as undetermined as the past. With irreversibility, the arrow of time is reintroduced to physics. Prigogine notes numerous examples of irreversibility, including diffusion, radioactive decay, solar radiation, weather and the emergence and evolution of life. Like weather systems, organisms are unstable systems existing far from thermodynamic equilibrium. Instability resists standard deterministic explanation. Instead, due to sensitivity to initial conditions, unstable systems can only be explained statistically, that is, in terms of probability. A while ago, I performed a computer simulation of the second law of thermodynamics. It involved a collection of identical entities that could be in one of two states, X or Y, with X transforming to Y and Y transforming to X at a rate governed by some rate constant. The simulation starts with all of the entities in state X, and proceeds to equilibrium. The conclusions that I drew from this simulation are: 1: The second law of thermodynamics is largely mathematical rather than physical because it is able to be simulated. 2: The rate constant is covariant with respect to time reversal. That is, it satisfies the requirement of general relativity. In other words, the thermodynamic arrow of time does not violate the principle of general relativity because the description remains valid even under time reversal. 3: The transition probability is not time reversible, applying only in the forward time direction. However, because the transition probability is based on entity counts, it is necessarily a positive number, unlike the corresponding time reversed value. 4: The transitions X to Y and Y to X in the forward time direction are not the same as the transitions Y to X and X to Y in the reverse time direction. The notion of microscopic reversibility refers to a transition and its reverse in the same time direction, not a transition in forward and reverse time directions. The transitions in the reverse time direction are not governed by transition probability. 5: Causality is governed by the transition probability and only exists in the forward time direction. The reverse time direction appears to be teleological. 1
sethoflagos Posted December 9, 2023 Posted December 9, 2023 50 minutes ago, KJW said: A while ago, I performed a computer simulation of the second law of thermodynamics. It involved a collection of identical entities that could be in one of two states, X or Y, with X transforming to Y and Y transforming to X at a rate governed by some rate constant. The simulation starts with all of the entities in state X, and proceeds to equilibrium. The conclusions that I drew from this simulation are: 1: The second law of thermodynamics is largely mathematical rather than physical because it is able to be simulated. 2: The rate constant is covariant with respect to time reversal. That is, it satisfies the requirement of general relativity. In other words, the thermodynamic arrow of time does not violate the principle of general relativity because the description remains valid even under time reversal. 3: The transition probability is not time reversible, applying only in the forward time direction. However, because the transition probability is based on entity counts, it is necessarily a positive number, unlike the corresponding time reversed value. 4: The transitions X to Y and Y to X in the forward time direction are not the same as the transitions Y to X and X to Y in the reverse time direction. The notion of microscopic reversibility refers to a transition and its reverse in the same time direction, not a transition in forward and reverse time directions. The transitions in the reverse time direction are not governed by transition probability. 5: Causality is governed by the transition probability and only exists in the forward time direction. The reverse time direction appears to be teleological. 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.
studiot Posted December 10, 2023 Posted December 10, 2023 (edited) On 12/8/2023 at 10:07 PM, geordief said: Are there other features of QM that could be described as essential in the way that it differs from Classical Physics? Other feature ? Other than what ? Here is some important ones. Firstly the photoelectric effect Classically there should be no threshold frequency to this effect. Yet observationally it is very sharply defined, as required by QM basic tenet that energy can only be accepted in certain quanta. So if the incoming photon does not have enough energy for the electron to transition to participate in a current, there is no current. In the Bohr atom and subsequent models, QM overcomes the classical problem of why an electron accelerating in the electrostatic field of the nucleus does not radiate its energy and fall into the nucleus. QM explains why the nucleus holds together (shell theory) Qm explains radioactive elements and radioactivity. QM explains observed spectra. QM explains band theory, metallic and semiconductor bonding and results in the non linear Konig Penny equation. These are all huge gains in our knowledge of how our world works. There are many other more specialist details but I note a discussion between @Luc Turpin and @Genady about 'our world' The core of the two major modern theories in Physics, relativity and QM were done and dusted and ironed out during the first half of the 20th century. This allowed many applications and also refinements and technology improvements to be made during the second half. Here is a very clear explanation of 'our world' from just after this half way point from two Princeton Professors, Dicke and Witke This clarity about Our world and physics (models) should also be of interest to @mar_mar In their book there is consider help transitioning from a classical mechanics to a quantum mechanics viewpoint. Also included is a whole chapter on the 'correspondence principle', using an interesting view of going backwards from QM to classical as a limit of very simple cases. Edited December 10, 2023 by studiot
Luc Turpin Posted December 10, 2023 Author Posted December 10, 2023 On science and the world, physics and non-linearity! I did a lot of thinking yesterday with little to show except for this: that science telling us what the world is all about as some people think, feels awkward. Should it not be that the world (universe) ought to be telling us through science what it wants to reveal to us? Science is the tool, not the subject matter!. In physics, at least for someone looking outside-in like me, it seems that there is a high rate of theorizing and calculating in comparison to experimenting. This theorizing-experimenting ratio appears to be much different in physics than in other sciences. I am aware that its the nature of the beast. Physics requires it. But what impacts this has on physics, I don’t know! Also, I cannot use math to corroborate things as I am too weak in it. And I found out that I cannot use key words to convey thoughts because the physics sense varies greatly from the conventional one. So, I am stuck in a pickle. What I can claim though with some degree of certainty is that probing the universe with science has put into light some of the non-linear features of complex systems. Seeing us no longer seeing ourselves. 1 hour ago, studiot said: These are all huge gains in our knowledge of how our world works. There are many other more specialist details but I note a discussion between @Luc Turpin and @Genady about 'our world' I will read this post very carefully! Thanks!
Genady Posted December 10, 2023 Posted December 10, 2023 2 hours ago, Luc Turpin said: Science is the tool, not the subject matter! It is a subject matter for some, e.g., Karl Popper, Thomas Kuhn, among others. 2 hours ago, Luc Turpin said: I cannot use math to corroborate things as I am too weak in it. This is too bad. Are you sure it is irreversible?
Luc Turpin Posted December 10, 2023 Author Posted December 10, 2023 8 minutes ago, Genady said: It is a subject matter for some, e.g., Karl Popper, Thomas Kuhn, among others. This is too bad. Are you sure it is irreversible? First line: interesting, need to think about it; Kuhn I like very much Second line: I am a hopeless case in math, but will try
studiot Posted December 10, 2023 Posted December 10, 2023 4 hours ago, Luc Turpin said: Also, I cannot use math to corroborate things as I am too weak in it. And I found out that I cannot use key words to convey thoughts because the physics sense varies greatly from the conventional one. So, I am stuck in a pickle. What I can claim though with some degree of certainty is that probing the universe with science has put into light some of the non-linear features of complex systems. And I am weak in my French, although my time at the lycee Francois Villion in Paris helped me immensely with my schoolboy French. But I think both of us are intelligent, after all you have mastered at least French and English, n'est ce pas ? 4 hours ago, Luc Turpin said: I did a lot of thinking yesterday with little to show except for this: that science telling us what the world is all about as some people think, feels awkward. Should it not be that the world (universe) ought to be telling us through science what it wants to reveal to us? Science is the tool, not the subject matter!. I do not think the world (universe) tells us anything as that would imply it was deliberately trying to communicate with us. Certainly it interacts with us an we interact with it. In doing so the interaction influences us and quantum theory is still debating how much we influence it. We learn not to put out hand into the fire. The passage from Dicke I posted has more to say on this. But in your statement you have done something very scientific. A very important theoretical scientific techique is to theoretically separate the 'subject of interest' into two parts and draw a line or boundary between them. Then to examine and study whatever passes across that boundary. You have drawn the boundary between us and the rest of the universe. Well done. You have mentioned non linearity twice in the last post and before that so let us look more deeply into the subject of linearity and non linearity. On 12/8/2023 at 9:44 PM, KJW said: Just in case you don't, an operator L() is linear if and only if it satisfies: L(ψ+ϕ)=L(ψ)+L(ϕ) Linearity is essential to QM because quantum superposition demands it. Not only do I agree with you, but I like the sentiment with which you posted something intended to be helpful. +1 But there is much more to linearity and linear Maths and linear Science than this so let us see how we get there. Essentialy linear means ' arranged in a (sensibly straight) line' Luc do you understand what I mean when I say 'sensibly straight' ? For example in particle physics the particles in a linear accelerator travel in a straight line whereas those in a cyclotron travel in a circle or spiral (ie a curved line). If I take the numbers 1, 2, 3, 4, 5, 6, 7, 8 , 9, 10, 11, 12, they are arranged in a straight line or linear order. But if I look at a clock face those same numbers are arranged around a circle so something is different. I have stuff to do now, but I will expand on this in my next post, where we will find the simplest of (schoolboy maths is non linear) Did I mention that we define 'linear' and declare that everything else is non linear. This is much much simpler than the other way round.
Luc Turpin Posted December 10, 2023 Author Posted December 10, 2023 1 hour ago, studiot said: I do not think the world (universe) tells us anything as that would imply it was deliberately trying to communicate with us. Certainly it interacts with us an we interact with it. In doing so the interaction influences us and quantum theory is still debating how much we influence it. We learn not to put out hand into the fire. The passage from Dicke I posted has more to say on this. But in your statement you have done something very scientific. A very important theoretical scientific techique is to theoretically separate the 'subject of interest' into two parts and draw a line or boundary between them. Then to examine and study whatever passes across that boundary. You have drawn the boundary between us and the rest of the universe. Well done. You have mentioned non linearity twice in the last post and before that so let us look more deeply into the subject of linearity and non linearity. I have comments-questions on your last post before this, but that will wait. Yes, meant interaction, not deliberately trying to communicate. Boundary between us and the universe is there, but there might be "bleeding" between the two. I might post something in neuroscience on mind. Far from being proven though. Linearity-non-linearity was reiterated in this post as a response to my debate with genady. And, I would like a deeper dive on this. 7 hours ago, studiot said: As much conditioned by human nature of mind as of nature of external world – yes, an interplay of both Limited by sense – yes. Brain as a computer – it is an older model of the brain The act of measuring (apologies to Joigus; their words; not mine) disturbs the system….. – can you substantiate? And the change from CM to QM was brought about by science prodding the universe and getting results that were inconsistent with CM; which comes back to science being the tool, not the subject matter as indicated in one of my previous posts
Genady Posted December 10, 2023 Posted December 10, 2023 2 hours ago, Luc Turpin said: science being the tool and scientific concepts / models being tools to deal with the world rather than representations of the world.
Luc Turpin Posted December 10, 2023 Author Posted December 10, 2023 1 minute ago, Genady said: and scientific concepts / models being tools to deal with the world rather than representations of the world. Yes
Luc Turpin Posted December 11, 2023 Author Posted December 11, 2023 14 hours ago, Genady said: and scientific concepts / models being tools to deal with the world rather than representations of the world. Upon reading it a second time and thinking about it, i would now say a greater yes than before
Genady Posted December 11, 2023 Posted December 11, 2023 12 minutes ago, Luc Turpin said: 14 hours ago, Genady said: and scientific concepts / models being tools to deal with the world rather than representations of the world. Upon reading it a second time and thinking about it, i would now say a greater yes than before and linearity / non-linearity are properties of the tools rather than of the world.
Luc Turpin Posted December 11, 2023 Author Posted December 11, 2023 Very interesting, I need to think about it. Like how your are leading the discussion With effects on the world? With effects on the comprehension of the world? Like leading a camel (me) to water
studiot Posted December 11, 2023 Posted December 11, 2023 39 minutes ago, Luc Turpin said: With effects on the world? With effects on the comprehension of the world? I think you mean what effects ? The impoetant thing to remember is that we define linearity and evrything else is non linear. I will do the next bit after lunch.
Luc Turpin Posted December 11, 2023 Author Posted December 11, 2023 15 minutes ago, studiot said: I think you mean what effects ? I do not understand the meaning 17 minutes ago, studiot said: The impoetant thing to remember is that we define linearity and evrything else is non linear. Please substantiate! I am grasping at straws to understand, but straws will be replaced by something more solid as I progress. I understand that non-linearity/linearity are part of the tools, but what does it say that they are required to deal with the world? Are they required to deal with the world or are they just there, static being part of the tools. The former implies implications for the world, right? I have a formidable advantage over all of you; I don’t understand as much as all of you
Luc Turpin Posted December 11, 2023 Author Posted December 11, 2023 1 hour ago, studiot said: I think you mean what effects ? Now I get it, yes what effects; I was a step back, wanting to know if there was an effect; what, then answers my previous question that there are
Genady Posted December 11, 2023 Posted December 11, 2023 1 hour ago, Luc Turpin said: Are they required to deal with the world How can we know this? 1 hour ago, Luc Turpin said: implications for the world Here is an analogy. To swim efficiently through water, fish evolved a slender profile. It implies something about the water. But it does not imply that the water has a slender profile. The water even does not have a profile. (To be clear about this analogy, our tools are like fish, the world is like the water.)
Luc Turpin Posted December 11, 2023 Author Posted December 11, 2023 It implies something of the water, but not linearity or non-linearity! Right? But it does say that slender bodies go through water more easily than wide bodies. And from this, we can Attribute properties to water, like maybe viscosity. Coming back full circle, can we say that the type of tool used is saying something about the world? Or for a commoner like me, not yet Knowing that non-l/l is a part of the tool, say something like Non-l/l shows that water in world has a certain degree of viscosity hope that I am not frustrating anyone.
Genady Posted December 11, 2023 Posted December 11, 2023 11 minutes ago, Luc Turpin said: It implies something of the water, but not linearity or non-linearity! Right? Right. 12 minutes ago, Luc Turpin said: But it does say that slender bodies go through water more easily than wide bodies. Not necessarily. There are other factors. Not all fish have slender profile. 13 minutes ago, Luc Turpin said: we can Attribute properties to water, like maybe viscosity. We can. But it will be another tool of us. 14 minutes ago, Luc Turpin said: can we say that the type of tool used is saying something about the world? Yes, we can. It says something. It does not say, what.
Luc Turpin Posted December 11, 2023 Author Posted December 11, 2023 It clarifies it, but need to think 4 minutes ago, Genady said: We can. But it will be another tool of us. I have to wrap my head around this one, can you expand? 7 minutes ago, Genady said: Not necessarily. There are other factors. Not all fish have slender profile. But, let’s say for argument purposes, there is only one factor, than the answer becomes yes? 10 minutes ago, Genady said: Yes, we can. It says something. It does not say, what. Can you expand on this one also?
Genady Posted December 11, 2023 Posted December 11, 2023 7 minutes ago, Luc Turpin said: I have to wrap my head around this one, can you expand? Viscosity is a concept that we have invented to deal with fluids. (And, not an easy one to grasp.) 9 minutes ago, Luc Turpin said: But, let’s say for argument purposes, there is only one factor, than the answer becomes yes? Yes. 15 minutes ago, Luc Turpin said: Can you expand on this one also? It says that the world is such that these tools work better than those tools.
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