Baseballs can’t be in two places at once. If the laws of physics did not change with scale we wouldn’t need different sets of equations with which to describe them.
Except you haven’t addressed the problem of why and when does quantum behaviour become classical behaviour. If you do know, I’ll try to attend your Nobel Prize presentation. 
Okay, so what **isn’t **information?
How could science exist without information? Also, information doesn’t have to be written down on paper; it exists everywhere, even within the structure of matter and space. A photon, for example, isn’t physical - it is a probability distribution, in other words, a ‘packet of information.’ By implication, going up the scale, macro objects are also information, so physical reality is nothing other than information. This is the most compelling interpretation of reality since it makes the least assumptions and does not lead to contradictions. Occam’s Razor applies here.
I did not say the the world was created by our subjective ideas. You have to have something with which our consciousness interacts. Again, this is information, but information itself is not sufficient to constitute reality. You need both. We live in a participatory universe. If people didn’t devise experiments and gathered data and then derive mathematical constructions from these there would be no science!
Science couldn’t, but the world wouldn’t be bothered.
Again, this is a strong claim regarding the interpretation of quantum mechanics that is currently not supported by actual quantum mechanics. I’ve told you this before, but there are two ways of interpreting a wave function: psi-onticism and psi-epistemicism. On the first, the wave function is just a physical wave, like an electromagnetic one. This is supported, for instance, by the PBR-theorem, which rules out many of the most natural psi-epistemic models.
On psi-epistemicism, the wave function isn’t an ‘element of reality’, to use a somewhat old-fashioned term, but rather, just an element of our description of reality, like, for instance, the probability distribution that results when I put either a red or green ball into a box. That’s an element of our knowledge, of the way we describe the world.
So you have two options: either the wave function is something like an electromagnetic wave, and thus, perfectly physical; or, it’s an element of our description of the world, only sort of summarizing what we know about a given system.
In neither case does the inference you want to draw follow: on psi-onticism, the wave function is just a physical field; on psi-epistemicism, the wave function doesn’t tell us anything about the world, but merely about what we know about the world. You sort of want to mix those two alternatives: the wave function describes our knowledge, and hence, is ‘informational’ in some ill-defined sense, but also describes physics, and consequently, physics is ‘informational’. You’re already tangled up in contradictions here.
You said, for example:
Or:
These are completely wrong ideas. I’ve outlined to you an experiment that yields different outcomes if consciousness did, indeed, collapse the wave function; and I’ve detailed how nothing about quantum mechanics implies that what existed before our consciousness interacted with it was just ‘a probability’.
What exists, exists independently from us; you just fall for the trap of associating properties of our models with the world they model. It’s like saying the ancient Greeks must have been made from marble, because all the statues depicting them are.
It doesn’t (and wouldn’t lead to your desired conclusion anyhow, since your view doesn’t add any explanatory power, but merely handwaves in the direction of the mysteries of consciousness). Occam basically ensures predictivity of theories: among two theories that explain the same data, you choose the one making less assumptions, as otherwise, you’d have no way to make any predictions, since you can always find a sufficiently baroque theory to ‘explain’ any experimental evidence. But here, we have different interpretations of a theory leading to the same predictions; parsimony simply isn’t well-defined in that case.
The world, however, would not care at all about that, and work according to the same laws.
But as Half Man Half Wit has been patiently explaining, we don’t need different sets of equations with which to describe them. We can describe both quantum and classical physics with the same set of equations. (The existence of various different but equivalent ways to formulate the single set of equations that can describe both quantum and classical physics, like the phase space/Hilbert space options mentioned earlier, doesn’t change that fact.)
The fact that classical and quantum mechanics are popularly considered by non-physicists to be somehow two different theories or models is just the result of a historical accident. Namely, scientists previously had more limited mathematical and technological tools for modeling and observing physical reality, so the simplified classical-physics version was developed first because it was more mathematically tractable. But that doesn’t mean that this simplified model actually represents any change in the laws of physics between quantum and macroscopic scales.
You’re using a lot of big words here, possibly to befuddle, I’m not sure. But, you talk of ‘interpreting’ but in my informational approach it really doesn’t matter how you interpret something because, in the final analysis, it’s all information. What is the difference between an EM wave and a probabilistic one? Essentially, no difference at all because both contain information that is accessible to us. Okay, things like EM waves must obey the laws of relativity, sure, and this highlights the fact that it is impossible to derive probabilistic waves from EM waves because until the birth of QM it was assumed everything was based on what was known at the time. There is no smooth, logical path from established knowledge to new knowledge because we can’t assume what is already known determines what is not yet known. That’s why we do experiments. The only objective we can realize is to gather new data or ‘information’ which is somehow embedded in the universe (or reality) and that is useless unless observed or measured by an ‘experimenter.’
If someone decide to conduct an experiment and put the process into place and then, for some mysterious reason, all human beings vanished from the face of the planet could we really say that the data from the experiment had any value? Well, not really because any data only has value after it has been understood or interpreted by some experimenter. From this, surely you can see that ‘reality’ can’t be ‘real’ in itself because we are part of reality and ‘it takes two to tango’, so to speak, therefore a universe without conscious observers of some form (and this could even be on the level of an amoeba) can only be half a universe. If Homo-Sapiens had not evolved, we would not, could not, be having this discussion, so what is the problem with including observers in the process of knowledge? And if one equates knowledge with reality then we have to conclude that observers are essential in defining reality itself.
Is this a joke?
So you’re saying we use Schrodinger’s equation with or instead of Newtonian laws?
Nonsense.
"Quantum mechanics is the science of the very small. It explains the behaviour of matter and its interactions with energy on the scale of atoms and subatomic particles.
By contrast, classical physics only explains matter and energy on a scale familiar to human experience, including the behaviour of astronomical bodies such as the Moon. Classical physics is still used in much of modern science and technology. However, towards the end of the 19th century, scientists discovered phenomena in both the large (macro) and the small (micro) worlds that classical physics could not explain."
What you probably mean is that newer models have been proposed in an attempt to unite both worlds but there still remain fundamental differences.
I’m sorry, no. What laws existed before people did experiments? The universe has to be coaxed into giving up laws, otherwise they remain purely as a ‘potential.’ You have to understand that stuff does not exist out there objectively. It’s all probabilistic and only stops being so on observation. Look at the double slit experiment. This shows it clearly.
No. I’m using exact terms here, for clarity. If something’s not clear to you, I’m always happy to explain.
The difference is that an EM wave is an excitation in a background electromagnetic field, while a probability is something abstract that tells us the likelihood for something to happen. If EM waves are still too abstract for you, take a water wave instead: the wave is the movement of water; however, the universe isn’t filled with some abstract ‘probability-stuff’ that could oscillate leading to a wave. Rather, it’s here our description that associates to different points in space and time different probabilities of events occurring.
And yes, once again: our models of water waves are mathematical, and hence, in some still not quite clear sense, ‘informational’. But that doesn’t imply that water is made from information anymore than if we would use clockworks to model it implies that it is made of clockworks.
This is nonsense. Quantum fields also obey the laws of relativity.
What reason would we have to assume that it didn’t? Of course, in principle, you don’t know that the space outside of your field of view isn’t just densely packed with Hitlers [1], but you also have no warrant, no justification to assume that this is the case.
The simplest assumption in line with all the available evidence is that indeed, the outcome would be exactly the same; and actually, the idea that conscious observation is special yields a theory different from quantum mechanics.
If we hadn’t evolved, we could not discuss these matters of fact, yes; but it doesn’t follow that hence, those wouldn’t be the very same matters of fact.
But why would somebody do something so silly? I know that Sherlock Holmes lived in Baker Street 221B; but that doesn’t mean Sherlock Holmes is real.
The fact that quantum mechanics includes classical mechanics, and hence, is a proper extension thereof into the relevant regime, was actually one of its guiding principles from the start, called by Bohr the correspondence principle. That Schrödinger’s equation leads to Newton’s laws was proven early on by Paul Ehrenfest. That classical mechanics can be described in the same terms as quantum mechanics (with baseballs being just as much described by a wave function as photons) was likewise demonstrated almost immediately after modern quantum mechanics was formulated.
No. This was really introduced in the very beginning: the correspondence principle came in 1920, Ehrenfest’s theorem in 1927, and in 1931, the Koopman-von Neumann formalism for classical mechanics was introduced. Von Neumann’s Mathematical Foundations of Quantum Mechanics, which is widely regarded as having introduced quantum mechanics in the form it is still used today, was published in 1932; so this sort of thing really was baked into QM from the start.
Of course, QM explains phenomena classical mechanics couldn’t explain: that’s why it was introduced in the first place. But it doesn’t do so in opposition to classical mechanics, but rather, as an extension of it into the realm of the ‘very small’ (actually, the realm where the action is comparable to Planck’s constant, which is often, but not necessarily that of small physical size).
Exactly the same ones as existed afterwards, since these laws are what brought people into existence in the first place; they’re thus the logical preconditions to us being here doing experiments.
Everything about the double slit experiment is perfectly compatible with stuff existing out there objectively. Quantum mechanics as it is presently formulated is inconsistent with the idea that consciousness leads to collapse of the wave function, and would have to be modified to accommodate it. Furthermore, the postulate of such an interactions yields no new insight: you replace the mystery of measurement with the even greater one of consciousness. So nothing is gained by such speculation, and it isn’t based in anything we currently know about the world.
I pointed you to the answers regarding the role of consciousness in the delayed-choice quantum eraser experiment, which resoundingly came down on the side of ‘none at all’. I pointed you to a poll of researchers in quantum foundations, of whom only 6% thought that consciousness has any fundamental role to play in QM. Tell me, did you ever think for a moment that maybe, just maybe, you’ve got things wrong? That when virtually all of the experts on the topic disagree with you, you’ve perhaps misunderstood something? That when the difference between those that advocate for a role of consciousness, and those who don’t believe there is such a role, is that the latter ones have actually studied and researched the topic for years, then maybe it’s those that aren’t familiar with the topic that are more likely to be wrong about it?
Nope, it makes perfect sense. But you need to understand at least a little physics to see why.
[QUOTE=abashed]
So you’re saying we use Schrodinger’s equation with or instead of Newtonian laws?
[/quote]
Absolutely! In fact, deriving the Newtonian laws of classical mechanics from quantum formulations including Schrödinger’s equation is one of the things that’s commonly done in college courses in quantum mechanics.
It is possible to do this because classical mechanics is simply a special case of quantum mechanics. The same quantum-physics laws apply equally to both of them: it’s just that the classical case happens to be a simpler instance of the general case, so you can talk about it using a mathematical approximation that’s much simpler to express.
[QUOTE=abashed]
Nonsense.
[/quote]
The fact that you think so only shows that you don’t know enough physics to understand this discussion in a meaningful way. As does your following quote:
[QUOTE=abashed]
"Quantum mechanics is the science of the very small. It explains the behaviour of matter and its interactions with energy on the scale of atoms and subatomic particles.
By contrast, classical physics only explains matter and energy on a scale familiar to human experience, including the behaviour of astronomical bodies such as the Moon. Classical physics is still used in much of modern science and technology. However, towards the end of the 19th century, scientists discovered phenomena in both the large (macro) and the small (micro) worlds that classical physics could not explain."
[/quote]
Just because classical physics can’t explain quantum physics doesn’t mean that quantum physics can’t explain classical physics. In fact, it can and does, because classical physics is just a simple special case of it.
[QUOTE=abashed]
What you probably mean is that newer models have been proposed in an attempt to unite both worlds but there still remain fundamental differences.
[/QUOTE]
Nope, what I mean is what I clearly said. There are no “fundamental differences” between classical physics and quantum physics, because the former is just a subset of the latter.
Here’s a little analogy: Suppose somebody assumed that all right-angled quadrilaterals (in Euclidean geometry yadda yadda) are squares. They could then come up with a bunch of nice theorems such as “The area of a right-angled quadrilateral is the length of its side multiplied by itself” and so forth. They call this branch of knowledge “square theory”.
Then this “square-theorist” happens to discover a non-square rectangle, which is indeed a right-angled quadrilateral, but one for which some of the known square-theory results don’t hold true. Yikes! :eek: No problem, we just need to generalize square theory to create “rectangle theory”, with a less restrictive definition of “right-angled quadrilateral” and consequently more general versions of some of the known results.
In this situation, square theory is in fact just a simpler subset of rectangle theory. Square theory can’t fully describe rectangle theory because it’s too restrictive, but rectangle theory can and does fully describe square theory. There are no “fundamental differences” between square theory and rectangle theory: the more powerful and general concepts of rectangles underlie, and are fully capable of describing, all the phenomena observed in squares.
Similarly, classical mechanics is just a subset of quantum mechanics, which underlies and is fully capable of describing all the classical phenomena.
And not terribly advanced ones. We teach this stuff to teenagers.
I think anomaly hunting can be added to your reasons why such nonsensical beliefs can be so cemented in some people. They see an anomaly, usually a minor anomaly or a controversial point on the cutting edge of a subject, and, not knowing how to reasonably treat such things, use the anomalies to selectively cast doubt on major scientific facts/theories that get in the way of their position.
How to deal with it? The blowback effect makes it difficult to do so with contradictory facts and argumentation, though these tend to be better for those who have not formed an opinion yet. I’d venture to guess that indirect means, such as forming a relationship with the person that doesn’t revolve around the argument at hand, are the only methods that would have a noticeable effect.
I would also add that those 6% have likely earned their opinion through their years of work even if they are wrong. Armchair scientists have not earned such an opinion, much less the stubbornness through which they may hold that opinion.
Wow. Just wow. When an expert uses precise scientific terms in a scientific discussion it’s to *clarify *the situation. If you don’t understand the terminology of the field you are arguing about ITS TIME TO STOP ARGUING ABOUT THAT FIELD.
Baseballs actually do have a wave function. The values of the function are very small, but the function does exist, and a baseball has a wave-nature.
We don’t “need” two sets of equations, save only for simplicity.
(e.g., when doing the Apollo mission, they didn’t take into account the gravitational attraction of Mars. But Mars did exert gravitational attraction on the Apollo spacecraft.)
You’re mistaking ordinary engineering simplification for “two sets of equations,” and I’m far from the first here to point out how wrong you are in this.
Exactly. We can. We don’t, for engineering purposes, because we don’t need that much precision.
We don’t use Einstein’s relativity equations when figuring out the speed of a racing car…but we do when calculating the position of GPS satellites.
The equations still apply! At no point does relativity “cease to be in effect.” We just don’t care, in working with racing cars, about the twelfth decimal place of accuracy.
(In astronomy, for very distant stars, astronomers use the function 1/x instead arctan x or, if you REALLY want to be persnickety, 2* arctan (1/2 x) For very, very small angles, the results are close to the same. The “error” is so small, nobody gives a hoot.)
I’m surprised…and maybe a little depressed…that it’s that high. What is their reasoning?
(Do they have any experimental evidence, or is it just philosophical arguments such as we’re seeing here in this thread?)
Here, I’m gonna actually side with abashed…a little.
Now, no, Half Man Half Wit is not guilty of the crime charged; as he himself noted, he’s seeking to clarify, not obfuscate, and he offered to explain.
But we have seen threads in the SDMB where experts pull out technical details that go beyond the necessary scope of the discussion, in order to overwhelm opposition. It is not terribly common, thank Ghu, but it has happened. So, no, not understanding a technically-accurate response is not always an indication that the recipient of the response is “too ignorant” to argue on the subject.