Adventures in Quantumland
Why we should be "profoundly shocked" at the nature of reality.
Ruth E. Kastner earned her M.S. in Physics and Ph.D. in History and Philosophy of Science from the University of Maryland. Since that time, she has taught widely and conducted research in Foundations of Physics, particularly in interpretations of quantum theory.
Adam Jacobs: Okay, so hi Dr. Kastner. Thank you so much for joining me today.
Ruth Kastner: Well, it's a pleasure. Thank you.
Adam Jacobs: It's my pleasure. And any friend of my friend, Ed Kelly from the Division of Perceptual Studies is a friend of mine and I have been really enjoying and delving into your book, which is about the quantum world. You have a couple of great credentials to me. You come from the world of philosophy and from the world of quantum physics and can speak cogently about both of them, which very few people I think in the contemporary world can.
And so I have a bunch of questions for you really, which focus on the ultimate nature of reality and how we come to understand what it is potentially. And in order to start things off, I figured I would quote one of the great quantum physicists, Neils Bohr, who said the following thing. He said, “Everything that we call real is made up of things we can't regard as real. If quantum mechanics hasn't profoundly shocked you, you haven't understood it yet.” So he lived a while ago already. My question for you is what should we conclude at this point? And this is a big question about the nature of reality, 125 years after the beginning of this research. Where are we holding? What has quantum mechanics told us about the way the world is?
Ruth Kastner: Well, yeah, I think I would have to start by kind of going back to Neils Bohr and the quote that you just reminded us of. And I guess my own position is somewhat heterodox in that I would've said, excuse me, Dr. Bohr, Professor Bohr, why are you saying you can't regard those things as real? So this is where I kind of take issue with some of our tendencies that come to us from the longstanding classical physics tradition to kind of define the term real in a way that ends up being rather tendentious and restricted to sort classical type notions.
So I have actually written a number of papers, a main paper where I do take direct issue with many of Bohr’s metaphysical pronouncements. So while he was of course a fantastic physicist and a pioneer of quantum theory, the challenges of the theory itself led him (and this of course understandable) tendency to want to have a classical sort of local, what we call local realistic account of reality, led him to say things like that.
It led him to dismiss the idea that quantum systems are real. So I guess I would just start sort of set the stage for our conversation by just letting your viewers know that I'm, again, largely a critic of many of the kinds of pronouncements that we get from the pioneers of quantum theory and from much of the mainstream, (current mainstream) views on quantum theory. So if I'm asked, well, where do we stand now, in my view, we're kind of stuck at a bit of a dead end in the mainstream accounting of quantum theory. It's stuck in sort of a tide pool that comes about because of the reluctance to kind of question many of these standard assumptions about what counts as real.
Adam Jacobs: Because it sounds like from his quote that he's acknowledging that non-reality produces reality because he says everything that we call real is made up of things we can't regard as real, which seems like he's acknowledging whatever it is that we can't regard as real does generate realities. Am I misreading that?
Ruth Kastner: Well, yes, he's, he's definitely acknowledging in the best way you can if your definition for what is real means classical solid concrete, what I would call actual, he's definitely doing the best he can to kind of accommodate this. And what I've been suggesting is that, again, the term real needs to be broadened so that it goes beyond what is really, (and this is a technical term maybe, but implicit actual meaning concrete), directly accessible to the senses, that kind of thing.
So insofar as somebody is tied to that kind of definition of real, that's sort of the best he can do and his heart is in the right place, definitely in saying we have to acknowledge that what we consider real is coming from something that seems very mysterious, very different from the kinds of things that we would usually count as real. So definitely insofar as he's suggesting that, then I understand, I sympathize with that expression. But again, I mean the reason I seem to come down a little bit hard on Bohr is that he really did later in his life kind of retreat into a sort of an anti-real view into saying things like, there is no quantum world. And he kind of hardened his stance to deny that whatever it is that's being described by quantum theory literally does not exist. And so there is where I really have to take issue with him.
Adam Jacobs: So for a lay person like myself, but somebody who has a strong interest in this subject matter, I don't see why anyone wouldn't be absolutely fascinated by this because it speaks to our shared experience as beings who are comprised of whatever the nature of the world ultimately is. So I don't see how you, it's hard for me to understand how people don't ruminate on this all the time, but be that as it may, one thing that I was thinking about as I was reading your book is we talk about the nature of reality.
And I love the way that you are pushing the boundaries and you're trying to incorporate more ideas of what counts as real into the discussion, which I think is absolutely critical. But what happens if once we get to the bottom of quantum reality, there's some other reality below it. What happens if, after another 125 years, we discover that things are vastly more complex and incomprehensible than we ever imagined? And the nature of things is wholly different than we had assumed, much like the difference between classical physics and quantum physics. My question to you is where does it end? Is there any termination of our investigation or is this something that could just go on for the rest of time?
Ruth Kastner: Well, yeah, this is where I guess it might be useful to kind of delineate that the scientific exploration as opposed to say the philosophical exploration, the scientific exploration is really kind of more circumscribed and delimited by its need for empirical grounding. So with science, we have to, (and this is the way it should be), we theorize, but ultimately we are responsible for testing our theories, for having some kind of a method of saying, here's what my theory would predict, or here's what it implies and you can go and check for this and see if I'm just making stuff up arbitrarily. So within that paradigm or within that scientific methodology, we are in a sense constrained to have theories that are corroborable in this sort of third-party environment. And that is kind of an intrinsic restriction to the scientific endeavor where there's really a necessity to be able to say, you can reproduce what I just experienced, and here's how you do it.
Now for the area of say, spiritual experience, personal inquiry, philosophical inquiry does not have that kind of constraint upon it. This is sort of a benefit and a compromise in a sense that it can be more powerful and it can allow you to explore more areas, but it also subjects you to a lot more skepticism where people can say, well, okay, you had a near-death experience, please show me which switches I should set to what settings in order to reproduce. And it's just not a third-party kind of corroboration that can take place. So this is where we have to say the sky's the limit as far as I'm concerned, as far as what we want to philosophically consider. And there's no sense in which it's not legitimate to continue asking questions and say, what more can I learn? What kind of experiences can I have?
But to the extent that these are going to be inner experiences that we can discuss in their experiences, but they aren't subject to this direct third-party data empirical corroboration. And so that's where science kind of has to go modestly. And I think the problem with the dialogue out there is often that scientists want to take science and extrapolate and pretend that they can make pronouncements about spiritual, internal, other kinds of experiences saying, physics says you can't have that experience, or whatever.
Or physics says that your sense of time is an illusion, or they kind of just overstep the legitimate boundaries of scientific exploration. So the short answer is it is certainly open-ended. It could be that what's going on at a fundamental level is something that is beyond the ability of traditional science to formulate theories about, but that doesn't mean that we can't learn about it, it's just that we have science needs to be respectful of other ways of knowing and not discount them simply because they aren't within the scientific methodology.
Adam Jacobs: I think that isn't a perfect segue into another quote that I have from another famous physicist who you write about in the book, which is Schrodinger. And he says the following, he says, “The scientific picture of the real world around me is very deficient. It gives a lot of factual information, but it cannot tell us a word about red or blue, bitter or sweet physical pain, and physical delight. It knows nothing of beauty and ugly, good or bad God and eternity. So in brief, we do not belong to this material world that science constructs for us, the scientific worldview contains of itself, not a word about our own ultimate scope or destination.”
So to me, that sounds extremely open-minded and right along the lines of what you were just describing, that there seems to be a limit to the procedures and the methodologies of science currently. And it strikes me again as a layperson that there's a moment, once the data has been accumulated and processed, where philosophy seems to naturally step in. So I have two questions. One, is that necessary in your way of thinking that the philosophy has to be tacked on to the end of the scientific process to make sense of the data that scientists produced? That's part one and part two is should scientists themselves engage in the process of philosophizing?
Ruth Kastner: Well, I would say that philosophy is in at the ground floor even of doing science, and properly done, science, in the sense that the whole empirical science approach, is a philosophical choice to proceed in a way that takes sense data as the given, if you will. And since data is concrete kinds of phenomena, it's a philosophical choice to say, alright, how am I going to now learn about the world? I'm going to talk about my sense impressions, and I'm going to give them names like matter. I'm going to say, okay, I hit my finger on this table and I felt something, and that I'm going to say that what I felt was caused by matter. So these are all philosophical choices of what procedure to follow, what kind of terminology to use, what counts as data, and so forth. So in fact, science used to be called natural philosophy.
That was the original empirical science. So we always have philosophy in there, and it's a philosophical choice to set up a kind of procedure called science and have rules for it, what counts as data, and then apply rational theorizing, mathematically rigorous theorizing to data and to come up with theories. This is because the empirical sciences have to be grounded in third-party corroboration. So this is how empirical science came about. It was a decision to say, okay, we're going to try learning about the world through this method. This method automatically rules out what you were talking about, what Schrodinger was talking about, how I feel, and whether I'm happy or sad. That doesn't count as data by fiat. So the empirical scientific endeavor was a choice to say, alright, we're going to have a game here, if you will, the rules of the game.
This is what counts as your data. You could formulate theories. And at the starting gate, it ruled out me being happy or sad, me finding meaning, my liking a painting, and so on. So those things were ruled out. And then we got some theories that were very useful and definitely seemed to tell us something about reality. And I think the mistake began to be assuming that because our procedure gave us these powerful theories that told us how fast a rock will fall and let us go to the moon and so on, that that's all there is in the world.
But again, that's sort of like saying you've got to hammer everything looks like a nail. So this is kind of the downside of that very powerful tool of empirical science. It's a great tool and it gives us lots of good information, but at the outset, it rules out meaning, it rules out internal realities, and so on. So that's again where philosophy is indispensable to help us to maintain our free inquiry and to note to be critical and to have some distance from the hammer of science. It's very interesting, but it's just a hammer.
And this is what I think people have forgotten. It's an amazing tool. It's a chainsaw, it's an incredibly powerful tool, but it's just a chainsaw. All you could do is chop things down. So that's kind of where I think we've been in an unfortunate situation with scientism and pretending like a chainsaw can tell you everything you need to know about your experience as a human being.
Adam Jacobs: I totally agree with everything that you're saying, but I have a question, third-party observation and the need for these standards in order for it to be considered scientific. Why then is the world of psychology a thing? Because psychology is entirely based off of subjective impressions of one's inner state, right? When someone says they're anxious or they're depressed or whatever they are, everyone seems to accept that as a reality. But like you were saying, a mystical experience, for instance, is not readily accepted. What is the difference between those two things? That the one seems wholly acceptable at this point and the other one wholly unacceptable unless you compartmentalize it into a religious thing versus a scientific thing.
Ruth Kastner: I think that has come about because much of psychology is, and again, I am not an expert in that field, but from what I've read, I think what tends to be more readily accepted as, okay, you're feeling depressed or you're feeling joyful, or, okay, I believe that that's a real thing is because there is the impression on the part of people of that persuasion that they can explain your experience physically. So there's kind of an implicit mechanistic physicalist trend I think in mainstream psychology in that what is acceptable is okay, your brain released a certain hormone and it made you feel sad.
So, on account of why you feel that you had an experience of a higher state of consciousness or something like that, or an experience of meaning of the sacred or something because that is not subject to a mechanistic, causal sort of physicalist account. And again, that's just kind of trying to give a possible reason why there might be that discrepancy where in mainstream psychology, certain internal experiences are considered, yeah, okay, I believe you. You're not making that up. You're not crazy or whatever. And then others are treated as, okay, whatever. I'm not sure I really want to believe that you had that experience. I don't know where I could get some pushback from psychologists on that and say, I'm not being fair. But it depends on what theory of psychology you're working with really.
Adam Jacobs: Right. Well, I could see a materialist either way saying, well, your depression is the result of this misfiring of your neurons or this chemical imbalance or whatever, but maybe your mystical experience is the same thing. Of course, there's a physical basis to it and you want to say you had it fine, you had it, but I'm not going to say that there's anything objectively real about it.
But okay, so you and I think are on the same page that we are highly willing to entertain the idea that there really is something beyond the physical world and the material brain and so on and so forth. And you use a term in the book that I have not heard used in this way in the past, which is, which I used to think was meant to be something spooky or something strange or scary or something like that. But I like the way that you use it, which is it's almost like there is what is known and then there is what is unknown and preternatural. It's not metaphysical per se. It's a description of something that we are coming to understand. Is that a good way of explaining that, the usage of that word?
Ruth Kastner: I think so. That's the way I understand the term, yes. That's the way I understand it, that it's to be contrasted with supernatural, which is used to mean something that is like, you don't even try to understand it, it's just, and something that would be rejected outright by any good scientist as just, well, science doesn't deal with the supernatural, but maybe something preternatural is simply something that could be given a scientific account, but we just don't have that account yet. So I think that's the distinction.
Adam Jacobs: Isn't that true of all human exploration in all human inquiry that what was considered magical at one point is just now your basic science now, I mean, if I introduced this phone a hundred years ago to anyone, they would've thought it was some kind of wizardry that you could contact a person across the globe instantaneously with this little thing. And of course, it's all readily explainable and whatnot, but knowing that, why wouldn't any thinker entertain the idea that down the road what we view as supernatural may certainly come to be believed, understood as perfectly natural?
Ruth Kastner: So the term natural, again, we need to kind of make a distinction. Here's why I make again that distinction between what can we consider a scientific kind of account and what about our experience might not be amenable to what we would call a scientific account, an empirical scientific account. And yet, and this is where I'm talking about physical sciences, an empirical theory that could predict say, I think the best way to get insight on this is to think about this flatland metaphor. And just very briefly, it's just the flatland story by Edwin Abbott where we have a plane that is the domain of existence of these two-dimensional figures, a square, and so on, and they think that's all they are able to experience empirically. Okay? So what I suggest is that physical science is by its nature, confined to that sort of flatland plane, metaphorically speaking, because that's the only way that you can get that crucial third-party corroboration.
So given that sort of analogy, you can think again about the flatland story, which involves this sphere coming in from the third dimension, which is not part of the empirical reality of the flatland creatures. And this sphere comes in, he does all kinds of crazy stuff that he intersects. It looks like a circle is growing bigger and bigger and then going away, and those are their empirical observations of this higher dimensional entity. So he's very mysterious, but someone could develop a theory about this higher dimensional entity and predict what you're going to see when this entity intersects and interacts with us. Well, I would suggest that quantum theory, and I suggest this in my books, is describing a kind of larger reality, but it's empirically we can give an empirical account to the extent that we can say, here's what we are going to experience in our flatland empirical world when these objects interact with us and they do all the time, and we can give an account of that.
However, consider the possibility of a square, Mr. Square sitting there in flatland and a sphere comes down and just kind of touches him in the stomach in what feels like his interior and then goes back out again. Nobody else, none of his other fellow flatland creatures, they did not experience that. Moreover, it was an internal experience for that square. It was not sort of on his external sensory organs around his periphery. This is the nature of a higher dimensional intersection with a lower dimensional reality it's felt as an internal thing. And by definition, it is not third-party corroborable.
So this could be a sense in which what we call spiritual experience is literally an experience of a higher dimensional reality that's there. It's ontologically there, it exists, but your fellow flatlanders are not going to believe you. They're going to want to say, well, give me your theory. When am I going to experience that? How to predict what? And you can't, right? So this is the distinction I would make that, and I'm not saying, oh, this is what spiritual experiences are, I don't know. All I'm saying is in a very rigorous, logical, geometric sense, there can be realities that are definitely there, but by their own nature, they're not going to be subject to third-party corroboration and therefore will not be subject to what we call a scientific account.
That's a great description of it. And I've read Flatlanders and I understand exactly what you're saying, but I think that's a perfect analogy actually. But do you think that that's what it means? For instance, when the famous Heisenberg Uncertainty principle, which suggests that you can't grasp a full picture of the quantum reality, if you know this, you can't know this. If you know this, you can't know some other component of a particle, is that because we're doing exactly what you just said, we are trying to grasp a whole by trying to isolate a part of it and say, oh, I understand what this part is, but meanwhile I don't have the perception capabilities to see what I'm really dealing with. Would that explain some of that uncertainty that we experience?
Ruth Kastner: In a way kind of, it's like trying to say, I would like this entire higher dimensional entity to fit in my lower dimensional reality. It can't, and in a sense, I mean, this is why I think of the quantum entities as a form of possibility so that they are physically real in the sense they're described by a physical theory, a theory of physics, and yet their nature is such that they're not what I call actuals an actual being something that metaphorically speaking could fit entirely in flatland that it's all there. Okay? All of it's just concrete, concrete in the sense that it's all available to you in your flatland domain, so to speak. The quantum entities can be understood as kind of a form of possibility where they can give rise to a number of different possible concrete empirical events, but they're too big. They have many possibilities, and you're not going to get all of those possibilities manifested in your smaller domain.
Adam Jacobs: So another metaphor you use in the book, which I really like is of the iceberg, and you describe our space reality as being above the waterline and everything else, the bigger part that's below the waterline is potentialities, and that those potentialities are giving rise to our spacetime reality. So that's fascinating. And you have another metaphor you use of weaving that a sweater or something is being woven in the course of time, and it's becoming, that's the word to use coming into reality as we understand it. Not that it wasn't real before, but not real as we experience it, which I like very much. So that generated a question for me, which is in what sense should I consider a potentiality real? And I'm not sure if this is a good question, but for instance, if I have the theoretical potential to be a doctor or an actuary, let's say, is there a concrete sense in which that's real for me? What does it mean that it exists in potential? If I don't actualize it, how does it exist?
Ruth Kastner: Here's where I do think we need to make a distinction between what is it that quantum theory describes and broader understandings of possibility in terms of what's possible for me as a person, I kind of restrict, when I say physically real, I restrict that to quantum entities. So it's a form of what I call physical potentiality that is directly describable by quantum theory. So it's a restricted definition, it's a restricted meaning of the term possibility. So I have to be, it's sort of like I can entertain, shall I dye my hair purple tomorrow? Well, that's a possibility. It's not described by quantum theory that I know, not that I know of.
So this is where I kind of make a distinction. I don't want to reify sort of thoughts that might occur that I might have an idea of something I could possibly do. So I wouldn't reify that in the same way that I think it's legitimate to say again to the flatland metaphor, that if our flatland square is sitting there and he sees these phenomena that are strange to him, they're described by a parallel sort of metaphorical quantum theory that can predict under what circumstances are you going to see that sphere do this weird circle happen, these phenomena.
So that's a very specific theory that has a restricted set of references. And those references are what I consider to be physical possibilities. And again, that's different from the kind of thought about what's possible for me, which is totally legitimate, but it's not something that is described by physical theory as far as I know.
Adam Jacobs: Okay. I have two more questions that I think I have time for. The first one is you talk about the concept of a block universe, which I'm only just learning a little bit about actually now from your book. And my understanding of that concept, the future already exists. It's really a question of where we're slicing the block to be able to perceive the present, the past, the future, but all of it is sort of done. So in that way of thinking, which I think you reject, you believe that the present is generating reality as we go, and it's not a finished product. So is the future in that way of thinking finite or infinite meaning in the block model, is the way that they're thinking, even though it's finished, does it go forever, or is there some termination points in the block universe?
Ruth Kastner: That could probably be, that would depend on what your block universe model is. I think that some would have a finite termination point, others might not. Yeah. When people talk about it, I usually hear that there's kind of an assumption that it is finite and one could possibly quibble about whether an infinite block universe is really sort of a consistent view. But again, not being a block world advocate, I don't really want to speak for that.
Adam Jacobs: Well, so I guess the reason I want to bring it up is why do some physicists prefer it? It seems like they view that there are some advantages in conceiving of the universe that way. What do you suppose those are?
Ruth Kastner: Well, I think that it comes out of sort of a tendency to kind of look at the map of space-time, sort of map that one can draw and saying, okay, this map, I can work with it. It's geometrically informative and taking that map as the territory and forgetting that my theory is sort of a map that can be useful and maybe predict certain things. It's not the same as the territory. If I'm driving to New York, my map is very useful, but it's not the real thing. And it comes from wanting to reify that map and take the map for the territory. And when you do that, you actually get constraints that seem to tell you, oh, no, I think that there has to be a complete future.
There are technical reasons why that happens, but it just comes from mistaking the map for the territory. Another reason people tend to want to do that is that it's a way to take what seems like the quantum mysteriousness, if you will, indeterminacy, and put it, come up with a description that makes everything seem more concrete, which is what we're used to. And to kind of say, let me just stipulate that all the measurement results that will ever be performed are going to just be there. And when we do that, we can, it's a kind of a hidden variable model that is a way of bringing back a concreteness that is dismissed by many people, but that I argue is kind of misguided that allows them to give that account that they want. So what that does is it basically kind of takes what we would call quantum states and makes them just kind of tools that kind of describe, well, what I don't know about the future.
And it makes everything determinate. And it's sort of a way of giving a narrative that takes, again, back to flatland, takes all of the space land stuff, projects it down into flatland, compresses out the uncertainty, and gives what looks like a logically consistent map that fits entirely in flatland. So that's kind of metaphorically speaking, I think what the block world is, is it's shrinking down a lot of this theoretical content so that it can be viewed as harmonious with my classical desire for concreteness. So that's why I don't like it. I think it's ad hoc, and I think it drains a lot of the content out of the actual theory in favor of compressing it and projecting it down to taking the bottom of the iceberg and chopping it off and saying, okay, whatever the theory is talking about, it's all actually in the tip. And there's the tip. It's all good, it's all concrete. You don't have to worry about that other stuff. We said it's not really there.
Adam Jacobs: So in closing for today, one of the things that concerns me about the physicalist doctrine, and this is something that comes from having direct experience and conversation with some very well-known physicists who hold that there is no free will, that there is no morality, there is no ultimate meaning. There is no survival of consciousness postmortem. And I believe that they believe it. I believe that they have concluded based on the research that this is the way the world is, and I would like it to be different, but what can I do? My concern is, is it that point of view? Not only is it very likely to me not correct, but I think that it promotes a kind of nihilism. I think that there's a bleakness in considering life from that perspective. My question is, knowing that the rates of depression and anxiety and a lot of other metrics for young people have skyrocketed in the last 10 or 20 years, I subjectively think it's partially due to the effectiveness of the materialist doctrine in promoting itself in the world and people losing a sense of hope.
What would you say as a scientist and a philosopher to somebody who was, let's say, had been raised thinking material reality is the only reality and has drawn whatever emotional conclusions as a result, what do you want young people to know about your work and the nature of reality that could be beneficial to them? That's a big question.
The scientists who purport to make proclamation theory are just actually incorrect about the implications of their physical theories. And they just simply have certain metaphysical assumptions that they have not examined. They often don't even know that they have them. Among them is the metaphysical assumption that what we call space-time is a delimiter, the container of everything real. And in fact, that's actually ruled out by general relativity itself. They haven't noticed that because they just haven't noticed it. So it's bad philosophy, it's bad science, it's overstepping one's authority.
A scientist to say, physics tells you that mechanistic, X, Y, Z in my various books and papers about what's wrong with those pronouncements, why they're not legitimate. So it's, it's erroneous. It's basically just bad science for scientists to state those as if they were categorically true. And it's unfortunate, I don't have time here, but I have various writings and presentations about why physics does not in any way rule out free will. Physics does not in any way tell us that we live in a block world. And that space-time, it tells us in many cases actually the opposite, and that those considerations simply aren't being entertained because of the conditioning, the traditions that we have in physics.
So it's a shame and it's so unnecessary. And again, it's like taking your hammer. It's a great tool. Your hammer or your chainsaw of empirical science and just chopping everything down with it and thinking that your hammer dictates the reality of the world. It's just a hammer. It's very useful, but it does not lead you. It does not allow you, it does not warrant the kinds of extrapolations and pronouncements about life and experience that are constantly being made. And it's a shame. And I just would encourage people to not buy it. Think for yourself, and read other sources. Whenever a physicist dogmatically tells you, physics implies x question it.
Very good. I will do that and I hope others will as well. It's been a real pleasure talking to you, and I hope that we're going to be on the West Coast within the next few months, I would love to see if we could come and talk in person. But it was great getting to know you and I encourage people to go and research those articles that you're referencing now and to bone up on science and philosophy, everyone for themselves, and let this be the people's work to come and understand their own reality, not necessarily just to rely on the experts. So thank you again. And for the audience, please take a moment to subscribe to our YouTube channel and go and check out our blog at beyondbelief.blog, we have lots more coming up for you. Thank you all for being here, and thank you, Dr. Kastner.
Ruth Kastner: Thank you, rabbi. It was a pleasure.
Adam Jacobs: Have a good day. Talk to you soon.