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Comment by ackbar03 | Hacker News Reader

Does anyone have a good recommendation for an introductory book on these concepts?

I read a bit of The Fabric of Reality but had trouble progressing too far with that one. The author talks about the quantum slit experiment, somehow arrives at the explanation of parallel universes, and then claims anyone who disagrees with this conclusion must have faulty logic. A huge chunk of reasoning behind parallel universes seems to be skipped and I have trouble taking it seriously every time it is brought up.

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Sean Carroll (professor of physics, quoted in the article) has a highly-rated book titled "Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime" [1] which discusses exactly these topics. I haven't read it, but it's on my list.

I also highly recommend his podcast "Mindscape" where he discusses this and a range of other topics in science and philosophy. [2]

[1] https://www.preposterousuniverse.com/somethingdeeplyhidden/ [2] https://www.preposterousuniverse.com/podcast/

You might check out the PBS Spacetime series on YouTube. https://www.youtube.com/@pbsspacetime

I love watching this channel even though it sounds like word salad to me

Judging by the comments, that seems to be a common sentiment among viewers :)

The problem with the channel at the moment is that it builds on top of previous episodes, I got into it when it was still understandable to me; check out the older videos and go from there.

I came here to reccomend this channel aswell. The "basics" were all covered years ago (6+), and now Matt is dipping into more complicated topics. If you find his recent videos overwhelming, I suggest to give his older ones a try.

For German speakers, I also recommend Josef Gaßner's YouTube series "Von Aristoteles zur Stringtheorie" (I find it a bit more structured than PBS Space Time, albeit maybe less amusing).

It seems to be well produced but the presenter rubs me the wrong way for some reason.

Just for context as a fellow interested noob: That book in particular is more like a manifesto than a survey, so it's not really intended to be 100% convincing, IMO. And AFAICT most of that book is about using the philosophy of the multiverse, not about justifying the physics -- so you definitely shouldn't feel bad coming away with that conclusion. An infinite multiverse is, to say the least, controversial!

For recommendations, assuming the linked articles themselves aren't up for grabs, I really liked The Rigor of Angels for a more historical-philosophical view on quantum physics, and how it compares to its predecessors. I also constantly reccommend this other Quanta article from a few years back, which is shorter and more cohesive than these: https://www.quantamagazine.org/what-is-a-particle-20201112/

Sadly, I think this whole field has an inherent level where it breaks down for non-experts, epistemologically speaking (how appropriate!). Watching Hossenfelder's engaging YouTube videos has taught me one thing above all else: I have no hope of critically engaging with the fine details of modern theories, only the metaphors and stories that surround the math.

What about if these people, despite their special terminology and maths, don't know either, and they're all just acting like they do? Stranger things have happened.

Great question and I’m hoping to see some other recommendations here.

In my opinion Coveney & Highfield’s 1990 survey “The Arrow of Time: A voyage through science to solve time's greatest mystery” is better than most for clearly connecting where theoretical approaches like many-worlds to the context they arise at the intersection of relativity, statistical thermodynamics, and quantum theory https://en.m.wikipedia.org/wiki/Special:BookSources/978-1-85...

As the book is 30+ years old and predates what I have to assume to be significant progress in the respective fields I would be keen to know if the experts here are aware of updated sources at any level (peer reviewed papers, monographs, etc.)

> A and then claims anyone who disagrees with this conclusion must have faulty logic. A huge chunk of reasoning behind parallel universes seems to be skipped and I have trouble taking it seriously every time it is brought up.

I think your scepticism is generally warranted. There is a reason the many-worlds interpretation is called an interpretation, just like the Copenhagen interpretation and others. The interpretations cannot be logically deduced from the experimental evidence we have. They are attempts to try to make sense of the results.

As for book recommendations, I have really liked Tim Maylin's "Philosophy of Physics: Quantum Theory" because of the precision and clarity he brings to the discussion. I should mention, though, that I've got a physics degree.

Tim Maudlin

Thanks, my phone's auto-correction at work :\

https://www.amazon.com/Physics-Symmetry-Undergraduate-Lectur...

There are great video series on YouTube, for example:

https://m.youtube.com/@pbsspacetime

https://m.youtube.com/@HistoryoftheUniverse

I often find videos easier to follow due to the great visuals.

You can also listen to interviews with the authors on podcasts. They talk about their books and the concepts in them.

And as always, your favorite LLM is a great companion to help you understand. I've consulted it several times and the answers and links it provided were very helpful

It’s very much a Copernican boundary: human beings desperately want to be at the center of things.

At one time this meant being at the center of the universe, today it’s more like wanting to be at the center of a unique identity with a deterministic past but an undetermined future.

This has led to countless interpretations of e.g. the Born Rule where humans have a unique ability to force wavefunction collapse with their senses.

Hugh Everett and those who subscribe to his post-Copernican view assert that we’re better off discarding the parochial attachment to a unique identify of experience than we are discarding theory validated by experiment beyond credible doubt.

One cannot truly avoid being human-centric, if the territory of reality is never available to one other than a map constructed by one’s consciousness. The core conceptual constructs used to reason about reality, the ways of attending to reality, the approaches to measuring it, this is all inherently coloured by humanness and further distinct cultural predispositions (a Western natural scientist is biased in one way, a !Kung shaman is biased in another). To assume the possibility of an unbiased take is unreasonable.

(There is never a complete map of the territory that covers the entirety of the territory in a way equally suitable for every possible use. Such a map would be the territory itself, which is not made directly available. So it’s good to have different maps, and to acknowledge that none of them can be assumed to be correct/complete.)

That said, assuming the hypothetical ability to cause what we refer to as “wavefunction collapse” via observation does not seem to strictly imply a human-centric view. Humans may be treated as a particular kind of conscious observer, but in a monistic idealist take assuming they are alone in that seems insufficient to describe reality.

Your argument isn’t with me, it’s with iconic physicists spanning the range from Sean Carrol to David Deutsch.

I’m well aware that any argument against vibes around an asymmetrically deterministic universe with a clear arrow of time and a unique dualist window of self is going to be unpopular.

There isn’t any physics there: how one chooses to interpret and integrate the vanishing impossibility of free will or unique identity is a very personal matter.

> Your argument isn’t with me, it’s with iconic physicists spanning the range from Sean Carrol to David Deutsch.

Of course, and (maybe more importantly) a number of philosophers. However, other philosophers (and, indeed, some iconic physicists) might not disagree.

> any argument against vibes around an asymmetrically deterministic universe with a clear arrow of time and a unique dualist window of self is going to be unpopular

Dualism is popular in general population, but monistic materialism is probably more popular among the tech crowd. Both approaches don’t strike me as elegant, naturally.

> how one chooses to interpret and integrate the vanishing impossibility of free will

Well, how one chooses to integrate the consciousness being the only thing that we can assume objectively exists (as the only thing we have direct access to, empirically) is also personal matter. The ways of waving it off (pretending it’s an illusion, etc.) are many… Once you stop doing that, though, suddenly free will is no longer such a crazy notion.

I’m not sure that a dichotomy between say illusory and real is the right category to examine consciousness with.

Consciousness is pretty difficult to define in any satisfactory way because we don’t have a way to know what another means by the word. I know how it feels to me, but not to you and vice versa. I’m aware that exceedingly clever people work on the problem and have for a very long time, and I hope they find some success, but I think it remains an open problem in most ways.

For my two cents I tend to think that pursuits like defining consciousness, or even higher level things like free will and even spirituality are very worthwhile, but likewise very difficult if not impossible to collaborate on with rigor.

I think I was a bit too flip in painting it as though consciousness and free will and spirituality are somehow inferior or less important topics than physics and cosmology and what not: put better I would say that they are very different pursuits and I think it perilous to try to integrate them under the guise of science. Physics can be done in collaboration with others, we have mediums for reaching some level of evolving consensus on that. Consciousness and free will are much less obviously amenable to any rigorous consensus.

Understood. I agree on difficulty with rigour, but then when you and I use “rigour” we mean it in a particular sense informed by the current philosophy of natural sciences. I suspect a possibility for rigour in other approaches, even if it looks not very rigorous to us in the framework of that philosophy.

> I think it perilous to try to integrate them under the guise of science

I may disagree on this somewhat, since physics can well be interpreted under monistic idealism where consciousness is a first-class citizen. The resistance may stem from it causing natural sciences (physics, etc.) to become subordinate to philosophy, which can be explained as an artefact of how science is done in our society (note how this anchors us again to humans and therefore consciousness): natural science allowed a lot of progress that benefitted our well-being (along with some consequences that potentially do not, cf. advanced weaponry), it gained certain status and many people don’t want it to lose that status for various reasons (maybe on occasion selfish ones). The resistance strikes me as misguided, natural sciences were in fact informed by philosophy, and philosophy may be evolving.

It’s like there was a healthy competition between different maps, natural sciences had won, but other maps are still useful (e.g., cases where modern medicine fails yet meditation/mindfulness do the trick are frequently mentioned even on HN), and competition would still be healthy. Perhaps I don’t need to be concerned and the conflict I want to remove via some universal philosophy is in fact evidence of competition keeping on and the plurality of maps. Maybe I in fact lament the lack of rigour that could benefit those other maps if modern science treated them seriously.

Humans also desperately want to find something that transcends them. But so far failed to find matching QM interpretation with new explanatory power.

Physics and mathematics have yet to answer age-old questions about the meaning of life, and it’s understandable that this would be disappointing! Our most intelligent people, adequately if not always amply funded to probe the deepest mysteries of the universe have come back with: “there is no evidence that it means anything, or really that it even happened in the way you mean”. Who wouldn’t be disappointed?

But this is ultimately a failure of our priests and politicians and parents: it’s not the job of scientists to be our nursemaids in an indifferent cosmos. We have people for that role, at least on paper.

"We have people for that role" is exactly the copernical boundary, that he transgressed :)

I recommend Carlo Rovelli's books.

I only read "The Order of Time" by him but it was very mind-bending to me. Paraphrased below.

He argues that time arrow (mostly) does not exist in classical or quantum physics, all equations run as well forward in time as backward.

The only area different is thermodynamics, and there he argues it is all due to our feeble mental capabilities. If we could observe and track each molecule's movement, time arrow would disappear again, we could easily run the system backwards.

He concludes that time is just a consciousness' invention to help make sense of the observed chaos. A more powerful mind would have no use for time.

I went out and borrowed this book after Carlo Rovelli was recommended, so far it has been indeed quite mind-bending

I think we're already at a point with LLMs (namely ChatGPT and Claude) where everyone has their own personalized Physics professor that you can ask any question you want. You can even say "explain it to me like I'm 5" and it will. You probably already knew this tho. :)

And the explanation may or may not be total nonsense.

Good luck figuring that out on subjects you don't understand.

Yeah, that's a good point. I just mean if someone reads a book, and fails to fully understand an explanation of some topic, it's more likely than not that an LLM can help them understand it, and do as good a job as a human expert could.

Take the content, paste it into chatgpt and ask it to explain it with simpler language, more details and examples.

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