I have very limited web access the next few days, so my responses might be slow.

Do you have a link? — T Clark

Hard to find links that don't spin an interpretation of the data, but this is brief description.

Nice post, but I'm curious about where we might disagree.

In the double-slit experiment, the detection of the photon at the back screen is not the only interaction that occurs in the system. It's just the obvious one since it involves someone observing it.

However there are also the distinct photon/slit interactions that occur. These constitute "measurements" between the photon and the apparatus independent of observer interaction and so also result in branching. The observed interference effect when we detect the photon on the back screen just is the interference of those branches (which is quantified as the sum of the wave amplitudes from both branches). — Andrew M

My interpretation of double-slit differs, but being an interpretation, there's no fact to it.

The measurement on the back screen results in one point, not a pattern, and only repeated runs reveal such a pattern. I would say the slits do not constitute a measurement, and that the photon is not a classic 'thing' that goes through one or the other. It is nothing but a wave function with probabilities of where it will be measured, and that function results in a wave interference pattern beyond the slits. The slits alter the wave function but no more. The guy observing the screen has nothing to do with the measurement. Consciousness is not part of the experiment.

Western philosophy warns us against it. Trust in ourselves is often betrayed. Isn't this why logic and rationality are so vehemently emphasized? We need an unbiased and reliable mediator between us and reality. That role is currently played by logic and it's doing a fine job. — TheMadFool

Good point. What's my response....? Thinking...? Still thinking...? First of all, logic and rationality are overrated. Deductive logic misses the whole point. It's inductive logic that matters - how do we get the ammunition to load into our deductive logical artillery? That's where we need whatever certainty we can muster. Which doesn't get me off the hook here. I'm just stalling for time.

How about this - "Western philosophy warns us against it. Trust in ourselves is often betrayed." True. I think that's the problem with Western philosophy. I guess what I should have said was "maybe that should be the fundamental fact of philosophy." Pretty lame. I'll keep thinking.

The Tao doesn't diminish the importance of reason and logic. In fact I think, owing to its poetic composition, it relies heavily on the reader's logic to infer the message the Tao wishes to convey. — TheMadFool

Strongly disagree with the second sentence. The Tao can't be understood, only experienced. It doesn't have a "poetic composition." For me, it is as literal as physics. Except that the base of "literal" means "letter," and the Tao that can be expressed in letters is not the eternal Tao. Which isn't to say I am in touch with the Tao. My experience is generally as intellectual as yours is. Those few times when I made direct contact, I knew it when I felt it.

That said, I think logic and rationality aren't enough to comprehend the whole of reality. Logic and reason fail at the scale of atoms and the universe. Didn't someone say ''if the only tool you have is a hammer, everything starts looking like a nail.'' Also ''the heart has reasons the mind knows not''. — TheMadFool

I think logic and rationality miss a lot at whatever scale you use them. As I said, to me, the Tao doesn't have anything to do with the heart.

It is nothing but a wave function with probabilities of where it will be measured, and that function results in a wave interference pattern beyond the slits. The slits alter the wave function but no more. — noAxioms

I was going to ask that but I was afraid to sound stupid. I thought it was the probability waves of the locations of the electrons that interfered with each other. Is that what you said.

I'll take a look at the link you sent.

Strongly disagree with the second sentence. The Tao can't be understood, only experienced. — T Clark

So, the Tao Te Ching is trying to express the inexpressible. This puzzles me. I too have had experiences that make my rational side uncomfortable - the vague feeling that reality hides a truth, that something wondrous lies beneath the surface, waiting to be understood/(in your words) experienced. However, this feeling is so difficult to analyze rationally that it frustrates me. Is it the same for you?

I think logic and rationality miss a lot at whatever scale you use them. As I said, to me, the Tao doesn't have anything to do with the heart. — T Clark

I agree. There's something more to reality than just logic and rationality. I think the very existence of the Tao Te Ching confirms that. Even Zen Buddhism speaks something along those lines. The question is ''what is it?"

So, the Tao Te Ching is trying to express the inexpressible. This puzzles me. I too have had experiences that make my rational side uncomfortable - the vague feeling that reality hides a truth, that something wondrous lies beneath the surface, waiting to be understood/(in your words) experienced. However, this feeling is so difficult to analyze rationally that it frustrates me. Is it the same for you? — TheMadFool

Get a copy of the Tao te Ching. Whatever version. I like Stephen Mitchell's, which is very Westernized. See if it affects you. The Tao is nothing hidden. It is not beneath the surface, it is the surface. It comes before rationality, logic, words, god, language, mathematics, and onion soup. It's right there in front of you right now. It comes before wonderous.

From time to time I experience it directly. Mostly I understand it intellectually, which is ironic. It's not rational. It requires a surrender.

An interesting notion. A measurement is being taken without a conscious observer. — Rich

The point is just that interactions between systems result in the entanglement of those systems. Observers are not special in this regard.

Just consder what that actually says — Wayfarer

OK, I'll rephrase.

In the double-slit experiment where a single photon is emitted and detected on the back screen, it is represented as being in a superposition of travelling through both slits. On the Everettian view, this indicates two physical branches where one photon travels through one slit on one branch and another photon travels through the other slit on the other branch. These branches then merge into one branch (i.e., interfere) before the photon is detected on the back screen. The detected photon's location on the back screen implies this two-branch history. However there is always only one photon on any particular branch.

The measurement on the back screen results in one point, not a pattern, and only repeated runs reveal such a pattern. — noAxioms

Yes, the observer measures the photon at just one point on the back screen. However if measurement is a linear process (and not a wave function collapsing or reducing process) then there is an observer measuring a photon at each point on the back screen where the wave function gives a probability of finding the photon. Which is what the Schrodinger's Cat thought experiment illustrates.

Just consider what that actually says
— Wayfarer

OK, I'll rephrase. — Andrew M

No - don't rephrase it. Consider the meaning of the three words: 'the universe branches'. Leave the double-slit out of it - just think about what is being claimed.

It's not rational. It requires a surrender. — T Clark

Thanks for the book recommendation.

There are free versions online.

Get a copy of the Tao te Ching. — T Clark

Agree. The fascinating thing is that no two translations are the same, in fact some verses read very differently in different translations. It's partially because of the obvious differences between Chinese and English, but it's also because many of the core terms are associated with profound ideas. In any case, it is very well worth being acquainted with, as is also the Chuang-Tzu, another Chinese classic (Burton Watson's translation is a standard, I think available from Penguin Classics.)

No - don't rephrase it. Consider the meaning of the three words: 'the universe branches'. Leave the double-slit out of it - just think about what is being claimed. — Wayfarer

What I am claiming is that the universe has a (quantum) branching structure rather than a classical linear structure.

I think that phrase expresses that. But if you think it implies multiple universes, then I don't endorse that claim. Otherwise perhaps you could spell out what you think the claim is.

that 'branching' means what it says - every outcome happens in as many universes as there are outcomes - which is infinitely many. It doesn't matter whether you endorse it or not - that is what the theory entails.

that 'branching' means what it says - every outcome happens in as many universes as there are outcomes - which is infinitely many. It doesn't matter whether you endorse it or not - that is what the theory entails. — Wayfarer

Well, first, branching does not entail more than one universe. A tree has branches, but it is only one tree. Secondly, it does not entail infinite outcomes. Only outcomes described by physical laws occur. A tree can have many branches but there are physical constraints on how many it can and does have.

branching does not entail more than one universe. — Andrew M

It most assuredly does. It was implicit in Everett's paper, and then made explicit later, that:

MWI's main conclusion is that the universe (or multiverse in this context) is composed of a quantum superposition of very many, possibly even non-denumerably infinitely many, increasingly divergent, non-communicating parallel universes or quantum worlds

Bryce Seligman DeWitt, R. Neill Graham, eds, The Many-Worlds Interpretation of Quantum Mechanics, Princeton Series in Physics, Princeton University Press (1973), p 140.

The implication is that there are infinitely many universes existing in parallel, in which everything that happens is replicated infinitely many times.

The implication is that there are infinitely many universes existing in parallel, in which everything that happens is replicated infinitely many times. — Wayfarer

First, your quote explicitly does not exclude a finite number of branches (i.e., it says "very many"). Second, it's no secret that people variously use "parallel universes", "multiverse", "many worlds" and so on to describe the Everettian idea. So what? It's clear from the context that they're referring to the directly visible universe that is familiar to us all. But the universe proper need not be limited to what can be directly seen. And, thirdly, the Everettian view does include competing versions, some of which may entail finite branching and others infinite branching.

The double-slit scenario I outlined earlier very clearly contains only two branches in superposition - there are no multiple universes or infinite branching implied there. You could try to show how that specific scenario has problems that you think are of concern.

your quote explicitly does not exclude a finite number of branches — Andrew M

It is not 'my quote'. It is a quote from the scientist who devised the term 'many worlds' for this theory (namely, Bryce DeWitt). The quote does not refer to 'branches', it says outright, plainly and simply, that the theory says the universe (or multiverse) comprises many universes.

the universe proper need not be limited to what can be directly seen — Andrew M

Recall the thread title. If the Universe proper is not so limited, then it's game over for objectivity. 'What cannot be directly seen' might include the Tao, the Creator, and who knows what.

You could try to show how that specific scenario has problems that you think are of concern. — Andrew M

The whole motivation for the so-called 'relative state formulation' is to avoid the observer effect or the collapse of the wave-function issue. The basic issue is that no objectively existent thing - no particle, as such - can be said to exist in any place, up until the time the measurement is made. A consequence of the measurement being made is that the wave function, which is a distribution of probabilities, collapses. This is why when a sensor is placed before the slit, then the particles act like particles and not waves - they produce a distribution pattern, not an interference pattern. So the implication of this is that the act of observation has physical consequences, which is the whole 'quantum weirdness' thing in a nutshell. That's why Einstein asked (rhetorically) 'does the moon continue to exist when you're not looing at it'. It's why qm is weird.

So to avoid that, Everett dreamed up something even weirder, about which it was later said:

Everett’s scientific journey began one night in 1954, he recounted two decades later, “after a slosh or two of sherry.” He and his Princeton classmate Charles Misner and a visitor named Aage Petersen (then an assistant to Niels Bohr) were thinking up “ridiculous things about the implications of quantum mechanics.” During this session Everett had the basic idea behind the many-worlds theory, and in the weeks that followed he began developing it into a dissertation.

The point is just that interactions between systems result in the entanglement of those systems. Observers are not special in this regard. — Andrew M

Schrodinger's equation and the Heisenberg Principle is about a measurement and a measurement requires an observer. What happens outside of the measurement it's speculation, assumptions and forever inaccessible. Bohm's real interpretation suggests something is happening, but what? Totally unknown and forever unknown.

It is impossible to unentangle the observation from quantum physics. Both the Schrodinger's equation and Heisenberg Principle are strictly about observation. One cannot arbitrarily separate observation (for convenience sake) from the essentiality of Quantum physics. If one does, one goes pact 400 years to Newtonian physics.

Listening to the Tao Te Ching in audiobook format is helpful, i find. Just letting it play over and over and letting the various meanings sink in. Ursula LeGuin's translation/reading is excellent. https://www.amazon.com/Lao-Tzu-Tao-Ching-Shambhala/dp/1570623740/ref=sr_1_7?ie=UTF8&qid=1498698516&sr=8-7&keywords=tao+te+ching+audiobook

And Jacob Needleman's wonderfully deep voice and nuanced reading add to this classic translation by Gia-Fu Feng and Jane English. https://www.amazon.com/Tao-Te-Ching/dp/B0000544P8/ref=sr_1_6?ie=UTF8&qid=1498698516&sr=8-6&keywords=tao+te+ching+audiobook

As mentioned above, Stephen Mitchell's translation is a more modern take perhaps. https://www.amazon.com/Tao-Te-Ching-Author-published/dp/B00Y4RNUC0/ref=sr_1_14?ie=UTF8&qid=1498698516&sr=8-14&keywords=tao+te+ching+audiobook

Incidentally just to unite these two disparate points about interpretation of physics, and Taoism, hereunder Niels Bohr's familial Coat of Arms, which he revised to reflect his 'wave-particle duality principle:

There are free versions online — T Clark

I downloaded S. Mitchell's Tao Te Ching. Thanks. The first line reads:

The Tao that can be called is not the Tao

Kinda makes me wonder what the whole book is about if the subject can't be "called".

Perhaps as one member said, it's as close an approximation to the truth as language will allow. Then I began to wonder if Lao Tze were alive today would his work be accepted in a reputed philosophical journal? If yes, why? If no, why?

'Named' is a better translation than 'called' in my opinion (any actual Chinese scholar, please feel free to correct me). The point, as I explained above, is that 'the named' is equivalent to 'the ten thousand things', meaning, the realm of phenomena or sensory experience. So to 'name' something is to locate it among the ten thousand things. But that's what language is for - 'hey, pass the spanner'. But when 'the Way' is named, it mis-locates it amongst 'the ten thousand things'. To name is to profane. In some ways it's a kind of a protest against blaspheming.

'Lao Tzu' is actually a generic name for Old Man or Wise Ancestor or something of that ilk. Analytic philosophy, it ain't.

erhaps as one member said, it's as close an approximation to the truth as language will allow. Then I began to wonder if Lao Tze were alive today would his work be accepted in a reputed philosophical journal? If yes, why? If no, why? — TheMadFool

From my own studies, Lao Tze probably did not exist as a single person but probably more of a composite, like Aesop. The Dao de Jing itself appears to be a compendium of stories, chants, advice probably gathered from many sources. Translations (of which there enumerable) are more or less a function of the skills and biases of the translator and are quite often at odds with each other. Words change and meaning of words change and of course context changes over time. There are some interesting ideas that can be found in the Dao De Jing if one wishes to study it, but my feeling is that actual experience via the arts is a better way. With that said, the Dao De Jing Genesis story it's probably the best I've read in describing the nature of the universe. Very succinct and to the point and quite prescient of quantum physics (note the wave symbol that represents the Genesis).

Very succinct and to the point and quite prescient of quantum physics (note the wave symbol that represents the Genesis). — Rich

I'm not a scientist and quantum physics is above my paygrade but I find it interesting that there's some sorta connection. It's actually amazing! What could be the basis of this link? Coincidence? Deliberate? I don't want to be the spoilsport but there are many similar claims - science in religious books - made by Islam and Hinduism. Is the Toaism-quantum physics connection more credible?

One gathers such insights via observation (which early Daoists excelled at because they were all about observing nature), personal experiences, and if course intuition based upon their observations. The essential thought is that everything is undergoing continuous wave-like change Yin/Yang) which is the manifestation of the movement created by the interaction of opposites (negative/positive). Given that this insight came thousands of years ago, speaks highly of their ability to observe and intuit.

The famous Daoist story about the farmer and the son speaks to the indeterminism of the universe:

"There was a farmer whose horse ran away. That evening the neighbors gathered to commiserate with him since this was such bad luck. He said, “May be.” The next day the horse returned, but brought with it six wild horses, and the neighbors came exclaiming at his good fortune. He said, “May be.” And then, the following day, his son tried to saddle and ride one of the wild horses, was thrown, and broke his leg.

Again the neighbors came to offer their sympathy for the misfortune. He said, “May be.” The day after that, conscription officers came to the village to seize young men for the army, but because of the broken leg the farmer’s son was rejected. When the neighbors came in to say how fortunately everything had turned out, he said, “May be.”

Source: Tao: The Watercourse Way, by Alan Watts

Great story! Maybe:P

From what I know, physics is about symmetry, electron-proton, matter-antimatter, etc., and this, I believe, is a feature of the mathematical models that aim to describe reality. If I recall correctly, these mathematical models have predicted particles whose existence were later verified through experimentation. Daoism is about duality which is also symmetry. Am I making sense?

Thanks.

There certainly is much symmetry and duality in nature and therefore physics. The primary insight of Daoism was that the fundamental stuff off the universe was a moving wave with negative and positive polarity (yin/yang), and the negative and positive created motion (qi). The Dao itself can be imagined as a universal intelligence, curling in within itself and thus creating the moving wave form. There is much to be gleamed from the Dao symbol.

Thanks, love that story, wanted to use it for a talk I'm giving next Tuesday, and didn't know the source.

You're welcome. Hoping your talk goes well.