Maybe they are right . . . . but . . .
Once upon a time there was a subject in school called geography.
The schoolboys learned: the Earth is flat.
=.=.
Ok, let's say we're in trouble. Do we just deny that we live in an objectively deterministic universe and live in fantasy? Does that change anything? Does it help our condition? Does it improve our future? LoisWe are not in trouble because at the macro level, we experience an adequately deterministic universe. However, we cannot assume that the universe is objectively deterministic, because of QM. As such, physicists are now exploring what is the origin and nature of time, space and causality versus what is experienced at the macro level, in their quest to understand what is the ultimate nature of the universe and whether it is objectively indeterministic. If it is not what we intuitively think and experience, we need new physics and theories and from the article here]
A successful theory of quantum gravity would merge quantum theory with Einstein’s theory of general relativity to describe every interaction in the universe that we know about, from the subatomic scale to the cosmological.We live in interesting times. :-) You wrote: However, we cannot assume that the universe is objectively deterministic, because of QM. Can you expand on that? How does QM affect whether the universe is deterministic? Lois
This might be true if we want to know the nature of reality, which is interesting academically.Exploring and understanding the ultimate nature of reality is not just interesting academically. And there are practical spin-offs in new technologies and devices which influence and affect our lives. For instance, QM has led to solid state electronics with the devices and systems we take for granted and use daily, including the internet for communication, banking and commerce worldwide.
But for our practical intents and purposes, assuming determinism is the way to go since indeterminism makes no difference to those.If we only consider classical physics it is practical, with adequate determinism but it is not justifiable to assume determinism in the universe, because of QM. OTOH, with QM and indeterminism as the ultimate nature of the universe, it is not necessarily a bad thing. We cannot foresee what QM and beyond will bring in the future. We do live in interesting times. :)
You wrote: However, we cannot assume that the universe is objectively deterministic, because of QM. Can you expand on that? How does QM affect whether the universe is deterministic?QM does not affect whether the universe is deterministic or indeterministic per se. But, from the wiki on quantum indeterminacy here]
Quantum indeterminacy is the apparent necessary incompleteness in the description of a physical system, that has become one of the characteristics of the standard description of quantum physics. Prior to quantum physics, it was thought that (a) a physical system had a determinate state which uniquely determined all the values of its measurable properties, and conversely (b) the values of its measurable properties uniquely determined the state.Bold added by me. And, from the wiki on indeterminism here]
In science, most specifically quantum theory in physics, indeterminism is the belief that no event is certain and the entire outcome of anything is a probability. The Heisenberg uncertainty relations and the “Born rule", proposed by Max Born, are often starting points in support of the indeterministic nature of the universe. Indeterminism is also asserted by Sir Arthur Eddington, and Murray Gell-Mann. Indeterminism has been promoted by the French biologist Jacques Monod's essay "Chance and Necessity". The physicist-chemist Ilya Prigogine argued for indeterminism in complex systems.Bold added by me. What QM has found is that, apparently, the universe is ultimately indeterministic, not deterministic. What is Tychism? From the same wiki cited above:
Tychism (Greek: τχη "chance") is a thesis proposed by the American philosopher Charles Sanders Peirce in the 1890s.[9] It holds that absolute chance, also called spontaneity, is a real factor operative in the universe. It may be considered both the direct opposite of Einstein's oft quoted dictum that: "God does not play dice with the universe" and an early philosophical anticipation of Werner Heisenberg's uncertainty principle. Peirce does not, of course, assert that there is no law in the universe. On the contrary, he maintains that an absolutely chance world would be a contradiction and thus impossible. Complete lack of order is itself a sort of order. The position he advocates is rather that there are in the universe both regularities and irregularities. Karl Popper comments[10] that Peirce's theory received little contemporary attention, and that other philosophers did not adopt indeterminism until the rise of quantum mechanics.Bold added by me. From the same wiki, clouds are not clocks:
Karl Popper In his essay Of Clouds and Cuckoos, included in his book Objective Knowledge, Popper contrasted "clouds", his metaphor for indeterministic systems, with "clocks", meaning deterministic ones. He sided with indeterminism, writing "I believe Peirce was right in holding that all clocks are clouds to some considerable degree — even the most precise of clocks. This, I think, is the most important inversion of the mistaken determinist view that all clouds are clocks"[14]Bold added by me. Also, from the same wiki, on indeterminism in Newtonian physics and Einsteinian relativity:
John Earman has argued that most physical theories are indeterministic.[22][23] For instance, Newtonian physics admits solutions where particles accelerate continuously, heading out towards infinity. By the time reversibility of the laws in question, particles could also head inwards, unprompted by any pre-existing state. He calls such hypothetical particles "space invaders". John D. Norton has suggested another indeterministic scenario, known as Norton's Dome, where a particle is initially situated on the exact apex of a dome.[24] Branching space-time is a theory uniting indeterminism and the special theory of relativity. The idea was originated by Nuel Belnap.[25] The equations of general relativity admit of both indeterministic and deterministic solutions.Bold added by me. Finally, from the same wiki, does the universe have alternating layers of causality and chaos?
Determinism and indeterminism are examined in Causality and Chance in Modern Physics by David Bohm. He speculates that, since determinism can emerge from underlying indeterminism (via the law of large numbers), and that indeterminism can emerge from determinism (for instance, from classical chaos), the universe could be conceived of as having alternating layers of causality and chaos.[36]There is much more to read and reflect in the wiki on indeterminism. My apologies for this long-winded post in reply to your query for expansion. :cheese:
Quantum discord and biology.
From this website here]
Quantum discord:
Quantum discord, a more general notion than quantum entanglement, is investigated from a theoretical viewpoint, and very general conditions for its existence are analysed.And biology:
As far as the more applied side, we have recently showed that quantum coherence and entanglement present in the retinas of European Robins have a high noise tolerance, and thus could play a role in avian bird nagivation. Another biological system which is being investigated by means of theoretical models as well as experiments are electron transport processes in the mitochondria, the cellular power plants.How about photosynthesis or the mind/brain and consciousness?
For instance, QM has led to solid state electronics with the devices and systems we take for granted and use daily, including the internet for communication, banking and commerce worldwide.Yes but you don't need and indeterministic theory of QM for that, still you can assume determinism with a hidden variables theory.
If we only consider classical physics it is practical, with adequate determinism but it is not justifiable to assume determinism in the universe, because of QM.It's justifiable unless it makes a practical difference not to.
And, from the wiki on indeterminism here]This is unclear because this could be true if causal determinism were true depending upon what it means. So what do you think it means Kkwan?In science, most specifically quantum theory in physics, indeterminism is the belief that no event is certain and the entire outcome of anything is a probability.
In science there are two concepts:
a) Classical causal determinism.
b) Quantum probability indeterminism.
Both concepts are correct.
Problem: the interaction between them is unclear.
== …
Yes but you don't need and indeterministic theory of QM for that, still you can assume determinism with a hidden variables theory.We do, because if QM was not proposed, such devices could not be developed and made with classical physics. To assume determinism with a hidden variables theory was ruled out by Bell's theorem. From the wiki here]
Bell's theorem is a no-go theorem that draws an important distinction between quantum mechanics (QM) and the world as described by classical mechanics. In its simplest form, Bell's theorem states:[1] No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics.Why these theories are no-go - the non-locality problem:
Bell's theorem states that any physical theory that incorporates local realism, favoured by Einstein,[7] cannot reproduce all the predictions of quantum mechanical theory. Because numerous experiments agree with the predictions of quantum mechanical theory, and show differences between correlations that could not be explained by local hidden variables, the experimental results have been taken by many as refuting the concept of local realism as an explanation of the physical phenomena under test. For a hidden variable theory, if Bell's conditions are correct, the results that agree with quantum mechanical theory appear to indicate superluminal effects, in contradiction to the principle of locality.Bold added by me. And from the section on metaphysical objections:
If one chooses to reject counterfactual definiteness, reality has been made smaller, and there is no non-locality problem. On the other hand, one is thereby introducing irreducible or intrinsic randomness into our picture of the world: randomness that cannot be "explained" as merely the reflection of our ignorance of underlying, variable, physical quantities. Non-determinism becomes a fundamental property of nature.Bold added by me.
It's justifiable unless it makes a practical difference not to.It is practical but not justifiable because of QM, notwithstanding utilitarian issues.
This is unclear because this could be true if causal determinism were true depending upon what it means.Causal order itself, is problematic, in QM. From this website here]
Surprisingly, we find correlations that cannot be understood in terms of definite causal order. These correlations violate a 'causal inequality' that is satisfied by all space-like and time-like correlations. We further show that in a classical limit causal order always arises, which suggests that space-time may emerge from a more fundamental structure in a quantum-to-classical transition.However, causal order does not imply causal determinism. What is causal determinism? From this definition here]
Causal Determinism finds that every event has an antecedent cause in the infinite causal chain going back to Aristotle's Prime Mover. There is nothing uncaused or self-caused (causa sui).Bold added by me. Infinite causal chain? And the universe is uncaused. So are quantum events. As such, causal determinism is misleading and false as causal chains are highly problematic beyond a few steps and there are uncaused quantum events, including the universe itself.
So what do you think it means Kkwan?It means if QM is true, reality is indeterministic.
To assume determinism with a hidden variables theory was ruled out by Bell's theorem.Well my understanding is that there are hidden variables theories, so I don't know which is true.
It means if QM is true, reality is indeterministic.Define real indeterminism
You wrote: However, we cannot assume that the universe is objectively deterministic, because of QM. Can you expand on that? How does QM affect whether the universe is deterministic?QM laws can only predict chance distributions of events, not single events. It turns out that this is not just a problem of our way of measuring, but it is principally built into nature. It is not the case that an electron or photon has a certain spin, andthat by measuring we change it in ways we cannot predict. The particles simply have no definite spin. As it turns out there can be no theory that can give a possible exact prediction based on a local reality below the one we are measuring. This possibility is experimentally excluded by so called EPR experiments]. This means that the universe is not fully determined. However, as for every macro object millions particles are involved, all these different simple events together lead to definite effects in the macro world. The light and dark stripes in an interference experiment will always look exactly the same because billions of photons are involved. On biological process there is, AFAIK no quantum process where single events make it into the macro world. So practically, we live in a determined world. However, determined does not mean predictable: in chaotic processes a very small change in the initial condition of a process can lead to totally different results. So even if we live in a practically determined world, that does not mean we live in a practically predictable world. Predictability we only have in situations where we can simply forget about the many particles involved (planets orbiting the sun), or situations where we artificially reduce the possibility that beginning conditions vary or lead to chaotic behaviour (technology).
In science there are two concepts: a) Classical causal determinism. b) Quantum probability indeterminism. Both concepts are correct. Problem: the interaction between them is unclear. == ....You did not read or understand any article about quantum decoherence.
Well my understanding is that there are hidden variables theories, so I don't know which is true.There are, but Bell's theorem indicate, from the quotation on Bell's theorem in my post 28:
For a hidden variable theory, if Bell’s conditions are correct, the results that agree with quantum mechanical theory appear to indicate superluminal effects, in contradiction to the principle of locality.This contradicts the principle of locality. OTOH, from the same quotation on Bell's theorem in my post 28:
If one chooses to reject counterfactual definiteness, reality has been made smaller, and there is no non-locality problem. On the other hand, one is thereby introducing irreducible or intrinsic randomness into our picture of the world: randomness that cannot be “explained" as merely the reflection of our ignorance of underlying, variable, physical quantities. Non-determinism becomes a fundamental property of nature.There is no non-locality problem, but indeterminism becomes a fundamental property of nature. From the wiki on Occam's razor here]
It states that among competing hypotheses, the one with the fewest assumptions should be selected. Other, more complicated solutions may ultimately prove correct, but—in the absence of certainty—the fewer assumptions that are made, the better.Hidden variables theories have too many assumptions........hidden variables, determinism, locality with non-superluminal effects and counterfactual definiteness which make them much more difficult to reconcile with all those assumptions, without contradictions.
Define real indeterminismFrom the wiki on indeterminism here]
Indeterminism is the concept that events (certain events, or events of certain types) are not caused, or not caused deterministically (cf. causality) by prior events. It is the opposite of determinism and related to chance. It is highly relevant to the philosophical problem of free will, particularly in the form of metaphysical libertarianism.And from this article here]
Logical philosophers describe indeterminism as simply the contrary of determinism. If a single event is undetermined, then indeterminism would be "true", they say, determinism is false, and this would undermine the very possibility of certain knowledge. Some go to the extreme of saying that indeterminism makes the state of the world totally independent of any earlier states, which is nonsense, but it shows how anxious they are about indeterminism. The core idea of indeterminism is closely related to the idea of causality. Indeterminism for some philosophers is an event without a cause (the ancient causa sui. But we can have an adequate causality without strict determinism, the "hard" determinism which implies complete predictability of events and only one possible future. We can call this "adequate determinism."