Radical ideas

 It’s hard to think of anyone I admire in physics and philosophy who doesn’t have at least one radical idea. Even Richard Feynman, who avoided hyperbole and embraced doubt as part of his credo: "I’d rather have doubt and be uncertain, than be certain and wrong."
 
But then you have this quote from his good friend and collaborator, Freeman Dyson:


Thirty-one years ago, Dick Feynman told me about his ‘sum over histories’ version of quantum mechanics. ‘The electron does anything it likes’, he said. ‘It goes in any direction at any speed, forward and backward in time, however it likes, and then you add up the amplitudes and it gives you the wave-function.’ I said, ‘You’re crazy.’ But he wasn’t.
 
In fact, his crazy idea led him to a Nobel Prize. That exception aside, most radical ideas are either still-born or yet to bear fruit, and that includes mine. No, I don’t compare myself to Feynman – I’m not even a physicist - and the truth is I’m unsure if I even have an original idea to begin with, be they radical or otherwise. I just read a lot of books by people much smarter than me, and cobble together a philosophical approach that I hope is consistent, even if sometimes unconventional. My only consolation is that I’m not alone. Most, if not all, the people smarter than me, also hold unconventional ideas.
 
Recently, I re-read Robert M. Pirsig’s iconoclastic book, Zen and the Art of Motorcycle Maintenance, which I originally read in the late 70s or early 80s, so within a decade of its publication (1974). It wasn’t how I remembered it, not that I remembered much at all, except it had a huge impact on a lot of people who would never normally read a book that was mostly about philosophy, albeit disguised as a road-trip. I think it keyed into a zeitgeist at the time, where people were questioning everything. You might say that was more the 60s than the 70s, but it was nearly all written in the late 60s, so yes, the same zeitgeist, for those of us who lived through it.
 
Its relevance to this post is that Pirsig had some radical ideas of his own – at least, radical to me and to virtually anyone with a science background. I’ll give you a flavour with some selective quotes. But first some context: the story’s protagonist, whom we assume is Pirsig himself, telling the story in first-person, is having a discussion with his fellow travellers, a husband and wife, who have their own motorcycle (Pirsig is travelling with his teenage son as pillion), so there are 2 motorcycles and 4 companions for at least part of the journey.
 
Pirsig refers to a time (in Western culture) when ghosts were considered a normal part of life. But then introduces his iconoclastic idea that we have our own ghosts.
 
Modern man has his own ghosts and spirits too, you know.
The laws of physics and logic… the number system… the principle of algebraic substitution. These are ghosts. We just believe in them so thoroughly they seem real.
 
Then he specifically cites the law of gravity, saying provocatively:
 
The law of gravity and gravity itself did not exist before Isaac Newton. No other conclusion makes sense.
And what that means, is that the law of gravity exists nowhere except in people’s heads! It’s a ghost! We are all of us very arrogant and conceited about running down other people’s ghosts but just as ignorant and barbaric and superstitious about our own.
Why does everybody believe in the law of gravity then?
Mass hypnosis. In a very orthodox form known as “education”.
 
He then goes from the specific to the general:
 
Laws of nature are human inventions, like ghosts. Laws of logic, of mathematics are also human inventions, like ghosts. The whole blessed thing is a human invention, including the idea it isn’t a human invention. (His emphasis)
 
And this is philosophy in action: someone challenges one of your deeply held beliefs, which forces you to defend it. Of course, I’ve argued the exact opposite, claiming that ‘in the beginning there was logic’. And it occurred to me right then, that this in itself, is a radical idea, and possibly one that no one else holds. So, one person’s radical idea can be the antithesis of someone else’s radical idea.
 
Then there is this, which I believe holds the key to our disparate points of view:
 
We believe the disembodied 'words' of Sir Isaac Newton were sitting in the middle of nowhere billions of years before he was born and that magically he discovered these words. They were always there, even when they applied to nothing. Gradually the world came into being and then they applied to it. In fact, those words themselves were what formed the world. (again, his emphasis)
 
Note his emphasis on 'words', as if they alone make some phenomenon physically manifest.
 
My response: don’t confuse or conflate the language one uses to describe some physical entity, phenomena or manifestation with what it describes. The natural laws, including gravity, are mathematical in nature, obeying sometimes obtuse and esoteric mathematical relationships, which we have uncovered over eons of time, which doesn’t mean they only came into existence when we discovered them and created the language to describe them. Mathematical notation only exists in the mind, correct, including the number system we adopt, but the mathematical relationships that notation describes, exist independently of mind in the same way that nature’s laws do.
 
John Barrow, cosmologist and Fellow of the Royal Society, made the following point about the mathematical ‘laws’ we formulated to describe the first moments of the Universe’s genesis (Pi in the Sky, 1992).
 
Specifically, he says our mathematical theories describing the first three minutes of the Universe predict specific ratios of the earliest ‘heavier’ elements: deuterium, 2 isotopes of helium and lithium, which are 1/1000, 1/1000, 22 and 1/100,000,000 respectively; with the remaining (roughly 78%) being hydrogen. And this has been confirmed by astronomical observations. He then makes the following salient point:



It confirms that the mathematical notions that we employ here and now apply to the state of the Universe during the first three minutes of its expansion history at which time there existed no mathematicians… This offers strong support for the belief that the mathematical properties that are necessary to arrive at a detailed understanding of events during those first few minutes of the early Universe exist independently of the presence of minds to appreciate them.
 
As you can see this effectively repudiates Pirsig’s argument; but to be fair to Pirsig, Barrow wrote this almost 2 decades after Pirsig’s book.
 
In the same vein, Pirsig then goes on to discuss Poincare’s Foundations of Science (which I haven’t read), specifically talking about Euclid’s famous fifth postulate concerning parallel lines never meeting, and how it created problems because it couldn’t be derived from more basic axioms and yet didn’t, of itself, function as an axiom. Euclid himself was aware of this, and never used it as an axiom to prove any of his theorems.
 
It was only in the 19th Century, with the advent of Riemann and other non-Euclidean geometries on curved surfaces that this was resolved. According to Pirsig, it led Poincare to question the very nature of axioms.
 
Are they synthetic a priori judgements, as Kant said? That is, do they exist as a fixed part of man’s consciousness, independently of experience and uncreated by experience? Poincare thought not…
Should we therefore conclude that the axioms of geometry are experimental verities? Poincare didn’t think that was so either…
Poincare concluded that the axioms of geometry are conventions, our choice among all possible conventions is guided by experimental facts, but it remains free and is limited only by the necessity of avoiding all contradiction.
 
I have my own view on this, but it’s worth seeing where Pirsig goes with it:
 
Then, having identified the nature of geometric axioms, [Poincare] turned to the question, Is Euclidean geometry true or is Riemann geometry true?
He answered, The question has no meaning.
[One might] as well as ask whether the metric system is true and the avoirdupois system is false; whether Cartesian coordinates are true and polar coordinates are false. One geometry can not be more true than another; it can only be more convenient. Geometry is not true, it is advantageous.
 
I think this is a false analogy, because the adoption of a system of measurement (i.e. units) and even the adoption of which base arithmetic one uses (decimal, binary, hexadecimal being the most common) are all conventions.
 
So why wouldn’t I say the same about axioms? Pirsig and Poincare are right in as much that both Euclidean and Riemann geometry are true because they’re dependent on the topology that one is describing. They are both used to describe physical phenomena. In fact, in a twist that Pirsig probably wasn’t aware of, Einstein used Riemann geometry to describe gravity in a way that Newton could never have envisaged, because Newton only had Euclidean geometry at his disposal. Einstein formulated a mathematical expression of gravity that is dependent on the geometry of spacetime, and has been empirically verified to explain phenomena that Newton couldn’t. Of course, there are also limits to what Einstein’s equations can explain, so there are more mathematical laws still to uncover.
 
But where Pirsig states that we adopt the axiom that is convenient, I contend that we adopt the axiom that is necessary, because axioms inherently expand the area of mathematics we are investigating. This is a consequence of Godel’s Incompleteness Theorem that states there are limits to what any axiom-based, consistent, formal system of mathematics can prove to be true. Godel himself pointed out that that the resolution lies in expanding the system by adopting further axioms. The expansion of Euclidean to non-Euclidean geometry is a case in point. The example I like to give is the adoption of √-1 = i, which gave us complex algebra and the means to mathematically describe quantum mechanics. In both cases, the axioms allowed us to solve problems that had hitherto been impossible to solve. So it’s not just a convenience but a necessity.
 
I know I’ve belaboured a point, but both of these: non-Euclidean geometry and complex algebra; were at one time radical ideas in the mathematical world that ultimately led to radical ideas: general relativity and quantum mechanics; in the scientific world. Are they ghosts? Perhaps ghost is an apt metaphor, given that they appear timeless and have outlived their discoverers, not to mention the rest of us. Most physicists and mathematicians tacitly believe that they not only continue to exist beyond us, but existed prior to us, and possibly the Universe itself.
 
I will briefly mention another radical idea, which I borrowed from Schrodinger but drew conclusions that he didn’t formulate. That consciousness exists in a constant present, and hence creates the psychological experience of the flow of time, because everything else becomes the past as soon as it happens. I contend that only consciousness provides a reference point for past, present and future that we all take for granted.

The mystery of reality

Many will say, ‘What mystery? Surely, reality just is.’ So, where to start? I’ll start with an essay by Raymond Tallis, who has a regular column in Philosophy Now called, Tallis in Wonderland – sometimes contentious, often provocative, always thought-expanding. His latest in Issue 157, Aug/Sep 2023 (new one must be due) is called Reflections on Reality, and it’s all of the above.
 
I’ve written on this topic many times before, so I’m sure to repeat myself. But Tallis’s essay, I felt, deserved both consideration and a response, partly because he starts with the one aspect of reality that we hardly ever ponder, which is doubting its existence.
 
Actually, not so much its existence, but whether our senses fool us, which they sometimes do, like when we dream (a point Tallis makes himself). And this brings me to the first point about reality that no one ever seems to discuss, and that is its dependence on consciousness, because when you’re unconscious, reality ceases to exist, for You. Now, you might argue that you’re unconscious when you dream, but I disagree; it’s just that your consciousness is misled. The point is that we sometimes remember our dreams, and I can’t see how that’s possible unless there is consciousness involved. If you think about it, everything you remember was laid down by a conscious thought or experience.
 
So, just to be clear, I’m not saying that the objective material world ceases to exist without consciousness – a philosophical position called idealism (advocated by Donald Hoffman) – but that the material objective world is ‘unknown’ and, to all intents and purposes, might as well not exist if it’s unperceived by conscious agents (like us). Try to imagine the Universe if no one observed it. It’s impossible, because the word, ‘imagine’, axiomatically requires a conscious agent.
 
Tallis proffers a quote from celebrated sci-fi author, Philip K Dick: 'Reality is that which, when you stop believing in it, doesn’t go away' (from The Shifting Realities of Philip K Dick, 1955). And this allows me to segue into the world of fiction, which Tallis doesn’t really discuss, but it’s another arena where we willingly ‘suspend disbelief' to temporarily and deliberately conflate reality with non-reality. This is something I have in common with Dick, because we have both created imaginary worlds that are more than distorted versions of the reality we experience every day; they’re entirely new worlds that no one has ever experienced in real life. But Dick’s aphorism expresses this succinctly. The so-called reality of these worlds, in these stories, only exist while we believe in them.
 
I’ve discussed elsewhere how the brain (not just human but animal brains, generally) creates a model of reality that is so ‘realistic’, we actually believe it exists outside our head.
 
I recently had a cataract operation, which was most illuminating when I took the bandage off, because my vision in that eye was so distorted, it made me feel sea sick. Everything had a lean to it and it really did feel like I was looking through a lens; I thought they had botched the operation. With both eyes open, it looked like objects were peeling apart. So I put a new eye patch on, and distracted myself for an hour by doing a Sudoku problem. When I had finished it, I took the patch off and my vision was restored. The brain had made the necessary adjustments to restore the illusion of reality as I normally interacted with it. And that’s the key point: the brain creates a model so accurately, integrating all our senses, but especially, sight, sound and touch, that we think the model is the reality. And all creatures have evolved that facility simply so they can survive; it’s a matter of life-and-death.
 
But having said all that, there are some aspects of reality that really do only exist in your mind, and not ‘out there’. Colour is the most obvious, but so is sound and smell, which all may be experienced differently by other species – how are we to know? Actually, we do know that some animals can hear sounds that we can’t and see colours that we don’t, and vice versa. And I contend that these sensory experiences are among the attributes that keep us distinct from AI.
 
Tallis makes a passing reference to Kant, who argued that space and time are also aspects of reality that are produced by the mind. I have always struggled to understand how Kant got that so wrong. Mind you, he lived more than a century before Einstein all-but proved that space and time are fundamental parameters of the Universe. Nevertheless, there are more than a few physicists who argue that the ‘flow of time’ is a purely psychological phenomenon. They may be right (but arguably for different reasons). If consciousness exists in a constant present (as expounded by Schrodinger) and everything else becomes the past as soon as it happens, then the flow of time is guaranteed for any entity with consciousness. However, many physicists (like Sabine Hossenfelder), if not most, argue that there is no ‘now’ – it’s an illusion.
 
Speaking of Schrodinger, he pointed out that there are fundamental differences between how we sense sight and sound, even though they are both waves. In the case of colour, we can blend them to get a new colour, and in fact, as we all know, all the colours we can see can be generated by just 3 colours, which is how the screens on all your devices work. However, that’s not the case with sound, otherwise we wouldn’t be able to distinguish all the different instruments in an orchestra. Just think: all the complexity is generated by a vibrating membrane (in the case of a speaker) and somehow our hearing separates it all. Of course, it can be done mathematically with a Fourier transform, but I don’t think that’s how our brains work, though I could be wrong.
 
And this leads me to discuss the role of science, and how it challenges our everyday experience of reality. Not surprisingly, Tallis also took his discussion in that direction. Quantum mechanics (QM) is the logical starting point, and Tallis references Bohr’s Copenhagen interpretation, ‘the view that the world has no definite state in the absence of observation.’ Now, I happen to think that there is a logical explanation for this, though I’m not sure anyone else agrees. If we go back to Schrodinger again, but this time his eponymous equation, it describes events before the ‘observation’ takes place, albeit with probabilities. What’s more, all the weird aspects of QM, like the Uncertainty Principle, superposition and entanglement, are all mathematically entailed in that equation. What’s missing is relativity theory, which has since been incorporated into QED or QFT.
 
But here’s the thing: once an observation or ‘measurement’ has taken place, Schrodinger’s equation no longer applies. In other words, you can’t use Schrodinger’s equation to describe something that has already happened. This is known as the ‘measurement problem’, because no one can explain it. But if QM only describes things that are yet to happen, then all the weird aspects aren’t so weird.
 
Tallis also mentions Einstein’s 'block universe', which infers past, present and future all exist simultaneously. In fact, that’s what Sabine Hossenfelder says in her book, Existential Physics:
 
The idea that the past and future exist in the same way as the present is compatible with all we currently know.
 
And:


Once you agree that anything exists now elsewhere, even though you see it only later, you are forced to accept that everything in the universe exists now. (Her emphasis.)
 
I’m not sure how she resolves this with cosmological history, but it does explain why she believes in superdeterminism (meaning the future is fixed), which axiomatically leads to her other strongly held belief that free will is an illusion; but so did Einstein, so she’s in good company.
 
In a passing remark, Tallis says, ‘science is entirely based on measurement’. I know from other essays that Tallis has written, that he believes the entire edifice of mathematics only exists because we can measure things, which we then applied to the natural world, which is why we have so-called ‘natural laws’. I’ve discussed his ideas on this elsewhere, but I think he has it back-to-front, whilst acknowledging that our ability to measure things, which is an extension of counting, is how humanity was introduced to mathematics. In fact, the ancient Greeks put geometry above arithmetic because it’s so physical. This is why there were no negative numbers in their mathematics, because the idea of a negative volume or area made no sense.
 
But, in the intervening 2 millennia, mathematics took on a life of its own, with such exotic entities like negative square roots and non-Euclidean geometry, which in turn suddenly found an unexpected home in QM and relativity theory respectively. All of a sudden, mathematics was informing us about reality before measurements were even made. Take Schrodinger’s wavefunction, which lies at the heart of his equation, and can’t be measured because it only exists in the future, assuming what I said above is correct.
 
But I think Tallis has a point, and I would argue that consciousness can’t be measured, which is why it might remain inexplicable to science, correlation with brain waves and their like notwithstanding.
 
So what is the mystery? Well, there’s more than one. For a start there is consciousness, without which reality would not be perceived or even be known, which seems to me to be pretty fundamental. Then there are the aspects of reality which have only recently been discovered, like the fact that time and space can have different ‘measurements’ dependent on the observer’s frame of reference. Then there is the increasing role of mathematics in our comprehension of reality at scales both cosmic and subatomic. In fact, given the role of numbers and mathematical relationships in determining fundamental constants and natural laws of the Universe, it would seem that mathematics is an inherent facet of reality.

 

Addendum:

As it happens, I wrote a letter to Philosophy Now on this topic, which they published, and also passed onto Raymond Tallis. As a consequence, we had a short correspondence - all very cordial and mutually respectful.

One of his responses can be found, along with my letter, under Letters, Issue 160. Scroll down to Lucky Guesses.
 

The fabric of the Universe

Brian Greene wrote an excellent book with a similar title (The Fabric of the Cosmos) which I briefly touched on here. Basically, it’s space and time, and the discipline of physics can’t avoid it. In fact, if you add mass and charge, you’ve got the whole gamut that we’re aware of. I know there’s the standard model along with dark energy and dark matter, but as someone said, if you throw everything into a black hole, the only thing you know about it is its mass, charge and angular momentum. Which is why they say, ‘a black hole has no hair.’ That was before Stephen Hawking applied the laws of thermodynamics and quantum mechanics and came up with Hawking radiation, but I’ve gone off-track, so I’ll come back to the topic-at-hand.
 
I like to tell people that I read a lot of books by people a lot smarter than me, and one of those books that I keep returning to is The Constants of Nature by John D Barrow. He makes a very compelling case that the only Universe that could be both stable and predictable enough to support complex life would be one with 3 dimensions of space and 1 of time. A 2-dimensional universe means that any animal with a digestive tract (from mouth to anus) would fall apart. Only a 3-dimensional universe allows planets to maintain orbits for millions of years. As Barrow points out in his aforementioned tome, Einstein’s friend, Paul Ehrenfest (1890-1933) was able to demonstrate this mathematically. It’s the inverse square law of gravity that keeps planets in orbit and that’s a direct consequence of everything happening in 3 dimensions. Interestingly, Kant thought it was the other way around – that 3 dimensions were a consequence of Newton’s universal law of gravity being an inverse square law. Mind you, Kant thought that both space and time were a priori concepts that only exist in the mind:
 
But this space and this time, and with them all appearances, are not in themselves things; they are nothing but representations and cannot exist outside our minds.
 
And this gets to the nub of the topic alluded to in the title of this post: are space and time ‘things’ that are fundamental to everything else we observe?
 
I’ll start with space, because, believe it or not, there is an argument among physicists that space is not an entity per se, but just dimensions between bodies that we measure. I’m going to leave aside, for the time being, that said ‘measurements’ can vary from observer to observer, as per Einstein’s special theory of relativity (SR).
 
This argument arises because we know that the Universe is expanding (by measuring the Doppler-shift of stars); but does space itself expand or is it just objects moving apart? In another post, I referenced a paper by Tamara M. Davis and Charles H. Lineweaver from UNSW (Expanding Confusion: Common Misconceptions of Cosmological Horizons and the Superluminal Expansion of the Universe), which I think puts an end to this argument, when they explain the difference between an SR and GR Doppler shift interpretation of an expanding universe.
 
The general relativistic interpretation of the expansion interprets cosmological redshifts as an indication of velocity since the proper distance between comoving objects increases. However, the velocity is due to the rate of expansion of space, not movement through space, and therefore cannot be calculated with the special relativistic Doppler shift formula. (My emphasis)
 
I’m now going to use a sleight-of-hand and attempt a description of GR (general theory of relativity) without gravity, based on my conclusion from their exposition.
 
The Universe has a horizon that’s directly analogous to the horizon one observes at sea, because it ‘moves’ as the observer moves. In other words, other hypothetical ‘observers’ in other parts of the Universe would observe a different horizon to us, including hypothetical observers who are ‘over-the-horizon’ relative to us.
 
But the horizon of the Universe is a direct consequence of bodies (or space) moving faster-than-light (FTL) over the horizon, as expounded upon in detail in Davis’s and Lineweaver’s paper. But here’s the thing: if you were an observer on one of these bodies moving FTL relative to Earth, the speed of light would still be c. How is that possible? My answer is that the light travels at c relative to the ‘space’* (in which it’s observed), but the space itself can travel faster than light.
 
There are, of course, other horizons in the Universe, which are event horizons of black holes. Now, you have the same dilemma at these horizons as you do at the Universe’s horizon. According to an external observer, time appears to ‘stop’ at the event horizon, because the light emitted by an object can’t reach us. However, for an observer at the event horizon, the speed of light is still c, and if the black hole is big enough, it’s believed (obviously no one can know) that someone could cross the event horizon without knowing they had. But what if it’s spacetime that crosses the event horizon? Then both the external observer’s perception and the comoving observer’s perception would be no different if the latter was at the horizon of the entire universe.
 
But what happens to time? Well, if you measure time by the frequency of light being emitted from an object at any of these horizons, it gets Doppler-shifted to zero, so time ‘stops’ for the ‘local’ observer (on Earth) but not for the observer at the horizon.
 
So far, I’ve avoided talking about quantum mechanics (QM), but something curious happens when you apply QM to cosmology: time disappears. According to Paul Davies in The Goldilocks Enigma: ‘…vanishing of time for the entire universe becomes very explicit in quantum cosmology, where the time variable simply drops out of the quantum description.’ This is consistent with Freeman Dyson’s argument that QM can only describe the future. Thus, if you apply a description of the future to the entire cosmos, there would be no time.
 
 
* Note: you can still apply SR within that ‘space’.

 

Addendum: I've since learned that in 1958, David Finkelstein (a postdoc with the Stevens Institute of Technology in Hoboken, New Jersey) wrote an article in Physical Review that gave the same explanation for how time appears different to different observers of a black hole, as I do above. It immediately grabbed the attention (and approval) of Oppenheimer, Wheeler and Penrose (among others), who had struggled to resolve this paradox. (Ref. Black Holes And Time Warps; Einstein's Outrageous Legacy, Kip S. Thorne, 1994)
 

Consciousness, free will, determinism, chaos theory – all connected

 I’ve said many times that philosophy is all about argument. And if you’re serious about philosophy, you want to be challenged. And if you want to be challenged you should seek out people who are both smarter and more knowledgeable than you. And, in my case, Sabine Hossenfelder fits the bill.
 
When I read people like Sabine, and others whom I interact with on Quora, I’m aware of how limited my knowledge is. I don’t even have a university degree, though I’ve attempted a number of times. I’ve spent my whole life in the company of people smarter than me, including at school. Believe it or not, I still have occasional contact with them, through social media and school reunions. I grew up in a small rural town, where the people you went to school with feel like siblings.
 
Likewise, in my professional life, I have always encountered people cleverer than me – it provides perspective.
 
In her book, Existential Physics; A Scientist’s Guide to Life’s Biggest Questions, Sabine interviews people who are possibly even smarter than she is, and I sometimes found their conversations difficult to follow. To be fair to Sabine, she also sought out people who have different philosophical views to her, and also have the intellect to match her.
 
I’m telling you all this to put things in perspective. Sabine has her prejudices like everyone else, some of which she defends better than others. I concede that my views are probably more simplistic than hers, and I support my challenges with examples that are hopefully easy to follow. Our points of disagreement can be distilled down to a few pertinent topics, which are time, consciousness, free will and chaos. Not surprisingly, they are all related – what you believe about one, affects what you believe about the others.
 
Sabine is very strict about what constitutes a scientific theory. She argues that so-called theories like the multiverse have ‘no explanatory power’, because they can’t be verified or rejected by evidence, and she calls them ‘ascientific’. She’s critical of popularisers like Brian Cox who tell us that there could be an infinite number of ‘you(s)’ in an infinite multiverse. She distinguishes between beliefs and knowledge, which is a point I’ve made myself. Having said that, I’ve also argued that beliefs matter in science. She puts all interpretations of quantum mechanics (QM) in this category. She keeps emphasising that it doesn’t mean they are wrong, but they are ‘ascientific’. It’s part of the distinction that I make between philosophy and science, and why I perceive science as having a dialectical relationship with philosophy.
 
I’ll start with time, as Sabine does, because it affects everything else. In fact, the first chapter in her book is titled, Does The Past Still Exist? Basically, she argues for Einstein’s ‘block universe’ model of time, but it’s her conclusion that ‘now is an illusion’ that is probably the most contentious. This critique will cite a lot of her declarations, so I will start with her description of the block universe:
 
The idea that the past and future exist in the same way as the present is compatible with all we currently know.
 
This viewpoint arises from the fact that, according to relativity theory, simultaneity is completely observer-dependent. I’ve discussed this before, whereby I argue that for an observer who is moving relative to a source, or stationary relative to a moving source, like the observer who is standing on the platform of Einstein’s original thought experiment, while a train goes past, knows this because of the Doppler effect. In other words, an observer who doesn’t see a Doppler effect is in a privileged position, because they are in the same frame of reference as the source of the signal. This is why we know the Universe is expanding with respect to us, and why we can work out our movement with respect to the CMBR (cosmic microwave background radiation), hence to the overall universe (just think about that).
 
Sabine clinches her argument by drawing a spacetime diagram, where 2 independent observers moving away from each other, observe a pulsar with 2 different simultaneities. One, who is traveling towards the pulsar, sees the pulsar simultaneously with someone’s birth on Earth, while the one travelling away from the pulsar sees it simultaneously with the same person’s death. This is her slam-dunk argument that ‘now’ is an illusion, if it can produce such a dramatic contradiction.
 
However, I drew up my own spacetime diagram of the exact same scenario, where no one is travelling relative to anyone one else, yet create the same apparent contradiction.

 My diagram follows the convention in that the horizontal axis represents space (all 3 dimensions) and the vertical axis represents time. So the 4 dotted lines represent 4 observers who are ‘stationary’ but ‘travelling through time’ (vertically). As per convention, light and other signals are represented as diagonal lines of 45 degrees, as they are travelling through both space and time, and nothing can travel faster than them. So they also represent the ‘edge’ of their light cones.
 
So notice that observer A sees the birth of Albert when he sees the pulsar and observer B sees the death of Albert when he sees the pulsar, which is exactly the same as Sabine’s scenario, with no relativity theory required. Albert, by the way, for the sake of scalability, must have lived for thousands of years, so he might be a tree or a robot.
 
But I’ve also added 2 other observers, C and D, who see the pulsar before Albert is born and after Albert dies respectively. But, of course, there’s no contradiction, because it’s completely dependent on how far away they are from the sources of the signals (the pulsar and Earth).
 
This is Sabine’s perspective:
 
Once you agree that anything exists now elsewhere, even though you see it only later, you are forced to accept that everything in the universe exists now. (Her emphasis.)
 
I actually find this statement illogical. If you take it to its logical conclusion, then the Big Bang exists now and so does everything in the universe that’s yet to happen. If you look at the first quote I cited, she effectively argues that the past and future exist alongside the present.
 
One of the points she makes is that, for events with causal relationships, all observers see the events happening in the same sequence. The scenario where different observers see different sequences of events have no causal relationships. But this begs a question: what makes causal events exceptional? What’s more, this is fundamental, because the whole of physics is premised on the principle of causality. In addition, I fail to see how you can have causality without time. In fact, causality is governed by the constant speed of light – it’s literally what stops everything from happening at once.
 
Einstein also believed in the block universe, and like Sabine, he argued that, as a consequence, there is no free will. Sabine is adamant that both ‘now’ and ‘free will’ are illusions. She argues that the now we all experience is a consequence of memory. She quotes Carnap that our experience of ‘past, present and future can be described and explained by psychology’ – a point also made by Paul Davies. Basically, she argues that what separates our experience of now from the reality of no-now (my expression, not hers) is our memory.
 
Whereas, I think she has it back-to-front, because, as I’ve pointed out before, without memory, we wouldn’t know we are conscious. Our brains are effectively a storage device that allows us to have a continuity of self through time, otherwise we would not even be aware that we exist. Memory doesn’t create the sense of now; it records it just like a photograph does. The photograph is evidence that the present becomes the past as soon as it happens. And our thoughts become memories as soon as they happen, otherwise we wouldn’t know we think.
 
Sabine spends an entire chapter on free will, where she persistently iterates variations on the following mantra:
 
The future is fixed except for occasional quantum events that we cannot influence.
 
But she acknowledges that while the future is ‘fixed’, it’s not predictable. And this brings us to chaos theory. Sabine discusses chaos late in the book and not in relation to free will. She explicates what she calls the ‘real butterfly effect’.
 
The real butterfly effect… means that even arbitrarily precise initial data allow predictions for only a finite amount of time. A system with this behaviour would be deterministic and yet unpredictable.
 
Now, if deterministic means everything physically manifest has a causal relationship with something prior, then I agree with her. If she means that therefore ‘the future is fixed’, I’m not so sure, and I’ll explain why. By specifying ‘physically manifest’, I’m excluding thoughts and computer algorithms that can have an effect on something physical, whereas the cause is not so easily determined. For example, In the case of the algorithm, does it go back to the coder who wrote it?
 
My go-to example for chaos is tossing coins, because it’s so easy to demonstrate and it’s linked to probability theory, as well as being the very essence of a random event. One of the key, if not definitive, features of a chaotic phenomenon is that, if you were to rerun it, you’d get a different result, and that’s fundamental to probability theory – every coin toss is independent of any previous toss – they are causally independent. Unrepeatability is common among chaotic systems (like the weather). Even the Earth and Moon were created from a chaotic event.
 
I recently read another book called Quantum Physics Made Me Do It by Jeremie Harris, who argues that tossing a coin is not random – in fact, he’s very confident about it. He’s not alone. Mark John Fernee, a physicist with Qld Uni, in a personal exchange on Quora argued that, in principle, it should be possible to devise a robot to perform perfectly predictable tosses every time, like a tennis ball launcher. But, as another Quora contributor and physicist, Richard Muller, pointed out: it’s not dependent on the throw but the surface it lands on. Marcus du Sautoy makes the same point about throwing dice and provides evidence to support it.
 
Getting back to Sabine. She doesn’t discuss tossing coins, but she might think that the ‘imprecise initial data’ is the actual act of tossing, and after that the outcome is determined, even if can’t be predicted. However, the deterministic chain is broken as soon as it hits a surface.
 
Just before she gets to chaos theory, she talks about computability, with respect to Godel’s Theorem and a discussion she had with Roger Penrose (included in the book), where she says:
 
The current laws of nature are computable, except for that random element from quantum mechanics.
 
Now, I’m quoting this out of context, because she then argues that if they were uncomputable, they open the door to unpredictability.
 
My point is that the laws of nature are uncomputable because of chaos theory, and I cite Ian Stewart’s book, Does God Play Dice? In fact, Stewart even wonders if QM could be explained using chaos (I don’t think so). Chaos theory has mathematical roots, because not only are the ‘initial conditions’ of a chaotic event impossible to measure, they are impossible to compute – you have to calculate to infinite decimal places. And this is why I disagree with Sabine that the ‘future is fixed’.
 
It's impossible to discuss everything in a 223 page book on a blog post, but there is one other topic she raises where we disagree, and that’s the Mary’s Room thought experiment. As she explains it was proposed by philosopher, Frank Jackson, in 1982, but she also claims that he abandoned his own argument. After describing the experiment (refer this video, if you’re not familiar with it), she says:
 
The flaw in this argument is that it confuses knowledge about the perception of colour with the actual perception of it.
 
Whereas, I thought the scenario actually delineated the difference – that perception of colour is not the same as knowledge. A person who was severely colour-blind might never have experienced the colour red (the specified colour in the thought experiment) but they could be told what objects might be red. It’s well known that some animals are colour-blind compared to us and some animals specifically can’t discern red. Colour is totally a subjective experience. But I think the Mary’s room thought experiment distinguishes the difference between human perception and AI. An AI can be designed to delineate colours by wavelength, but it would not experience colour the way we do. I wrote a separate post on this.
 
Sabine gives the impression that she thinks consciousness is a non-issue. She talks about the brain like it’s a computer.
 
You feel you have free will, but… really, you’re running a sophisticated computation on your neural processor.
 
Now, many people, including most scientists, think that, because our brains are just like computers, then it’s only a matter of time before AI also shows signs of consciousness. Sabine doesn’t make this connection, even when she talks about AI. Nevertheless, she discusses one of the leading theories of neuroscience (IIT, Information Integration Theory), based on calculating the amount of information processed, which gives a number called phi (Φ). I came across this when I did an online course on consciousness through New Scientist, during COVID lockdown. According to the theory, this number provides a ‘measure of consciousness’, which suggests that it could also be used with AI, though Sabine doesn’t pursue that possibility.
 
Instead, Sabine cites an interview in New Scientist with Daniel Bor from the University of Cambridge: “Phi should decrease when you go to sleep or are sedated… but work in Bor’s laboratory has shown that it doesn’t.”
 
Sabine’s own view:
 
Personally, I am highly skeptical that any measure consisting of a single number will ever adequately represent something as complex as human consciousness.
 
Sabine discusses consciousness at length, especially following her interview with Penrose, and she gives one of the best arguments against panpsychism I’ve read. Her interview with Penrose, along with a discussion on Godel’s Theorem, which is another topic, discusses whether consciousness is computable or not. I don’t think it is and I don’t think it’s algorithmic.
 
She makes a very strong argument for reductionism: that the properties we observe of a system can be understood from studying the properties of its underlying parts. In other words, that emergent properties can be understood in terms of the properties that it emerges from. And this includes consciousness. I’m one of those who really thinks that consciousness is the exception. Thoughts can cause actions, which is known as ‘agency’.
 
I don’t claim to understand consciousness, but I’m not averse to the idea that it could exist outside the Universe – that it’s something we tap into. This is completely ascientific, to borrow from Sabine. As I said, our brains are storage devices and sometimes they let us down, and, without which, we wouldn’t even know we are conscious. I don’t believe in a soul. I think the continuity of the self is a function of memory – just read The Lost Mariner chapter in Oliver Sacks’ book, The Man Who Mistook His Wife For A Hat. It’s about a man suffering from retrograde amnesia, so his life is stuck in the past because he’s unable to create new memories.
 
At the end of her book, Sabine surprises us by talking about religion, and how she agrees with Stephen Jay Gould ‘that religion and science are two “nonoverlapping magisteria!”. She makes the point that a lot of scientists have religious beliefs but won’t discuss them in public because it’s taboo.
 
I don’t doubt that Sabine has answers to all my challenges.
 
There is one more thing: Sabine talks about an epiphany, following her introduction to physics in middle school, which started in frustration.
 
Wasn’t there some minimal set of equations, I wanted to know, from which all the rest could be derived?
 
When the principle of least action was introduced, it was a revelation: there was indeed a procedure to arrive at all these equations! Why hadn’t anybody told me?
 
The principle of least action is one concept common to both the general theory of relativity and quantum mechanics. It’s arguably the most fundamental principle in physics. And yes, I posted on that too.

 

Kant and modern physics

 I wrote a post on Kant back in February 2020, but it was actually an essay I wrote more than 20 years earlier, when I was a student of philosophy. I would not be able to improve on that essay, and I’m not about to try now. In that essay, I argue that Kant’s great contribution to philosophy, and epistemology in particular, was his idea of the ‘thing-in-itself’, which may remain forever unknowable, as we only have our perceptions of ‘things’.
 
In other posts, I have sometimes argued that the ‘thing-in-itself’ is dependent on the scale that we can observe it, but there is something deeper that I think only became apparent in the so-called golden age of physics in the 20th Century. In a more recent post, I pointed out that both relativity theory and quantum mechanics (the 2 pillars of modern physics) are both observer dependent. I argue that there could be an objective ontology that they can’t describe. I think this is more obvious in the case of special relativity, where different observers literally measure different durations of both space and time, but I’m getting ahead of myself.
 
On Quora, there are 4 physicists whom I ‘follow’ and read regularly. They are Viktor T Toth, Richard Muller, Mark John Fernee and Ian Miller. Out of these, Miller is possibly the most contentious as he argues against non-locality in QM (quantum mechanics), which I’m not aware of any other physicist concurring with. Of course, it’s Bell’s Inequality that provides the definitive answer to this, of which Miller has this to say:
 
If you say it must because of violations of Bell’s Inequality, first note that the inequality is a mathematical relationship that contains only numbers; no physical concept is included.
 
But the ‘numbers’ compare classical statistical outcomes with Born statistical outcomes and experiments verify Born’s results, so I disagree. Having said that, Miller makes pertinent points that I find insightful and, like all those mentioned, he knows a lot more about this topic than me.
 
For example, concerning relativity, he argues that it’s the ruler that changes dimension and not the space being measured. He also points out, regarding the twin paradox, that only one twin gains energy, which is the one whose clock slows down. Note that clocks are also a form of ‘ruler’, but they measure time instead of space. So you can have 2 observers who ‘measure’ different durations of space and time, but agree on ‘now’, when they reunite, as is the case with the twin paradox thought experiment.
 
This point is slightly off-track, but not irrelevant to the main focus of this post. The main focus is an academic paper jointly written by Shaun Maguire and Richard Muller, titled Now, and the Flow of Time. This paper is arguably as contentious as Miller’s take on non-locality and Bell, because Muller and Maguire argue that ‘space’ can be created.
 
Now, Viktor T Toth is quite adamant that space is not created because space is not an entity, but a ‘measurement’ between entities called ‘objects’. Now, it has to be said, that Muller has stated publicly on Quora that he has utmost respect for Toth and neither of them have called each other out over this issue.
 
Toth argues that people confound the mathematical metric with ‘space’ or ‘spacetime’, but I’d argue that this mathematical metric has physical consequences. In another post, I reference another paper, recommended to me by Mark John Fernee (authored by Tamara M. Davis and Charles H. Lineweaver at the University of New South Wales) which describes how a GR Doppler shift intrinsically measures the expansion of space.
 
The general relativistic interpretation of the expansion interprets cosmological redshifts as an indication of velocity since the proper distance between comoving objects increases. However, the velocity is due to the rate of expansion of space, not movement through space, and therefore cannot be calculated with the special relativistic Doppler shift formula. (My emphasis)
 
As I explain in that post: ‘What they are effectively saying is that there is a distinction between the movement of objects in space and the movement of space itself.’
 
The spacetime metric that Toth refers to provides a reference frame for c, the speed of light. So, whilst a spacetime metric (‘space’ by another name) can travel faster than light with respect to us (so over the horizon of the observable universe), an observer situated in that metric would still measure light as c relative to them.
 
Muller’s and Maguire’s paper goes even further, saying that space is created along with time, and they believe this can be measured as ‘a predicted lag in the emergence of gravitational radiation when two black holes merge.’ I won’t go into the details; you would need to read the paper.
 
A conclusion implicit in their theory is that there could be a universal now.
 
A natural question arises: why are the new nows created at the end of time, rather than uniformly throughout time, in the same way that new space is uniformly created throughout the universe.
 
The authors then provide alternative arguments, which I won’t go into, but they do ponder the fundamental difference between space and time, where one is uni-directional and the other is not. As far as we know, there is no ‘edge’ in space but there is in time. Muller and Maguire do wonder if space is ‘created’ throughout the Universe (as quoted above) or at an ‘edge’.
 
You may wonder how does Kant fit into all this? It’s because all these discussions are dependent on what we observe and what we theorise, both of which are perceptions. And, in physics, theorising involves mathematics. I’ve argued that mathematics can be seen as another medium determining perceptions, along with all the instruments we’ve built that now include the LHC and the Hubble and Webb telescopes.
 
Sabine Hossenfelder, whom I often reference on this blog these days, wrote a book, called Lost in Math, where she interviews some of the brightest minds in physics and challenges the pervading paradigm that mathematics can provide answers to questions that experimentation can’t – string theory being the most obvious.

Before the revolution in cosmology, created by Copernicus and built on by Galileo, Kepler and Newton, people believed that the Sun went round the Earth and that some objects in the night sky would occasionally backtrack in their orbits, which was explained by epicycles. That was overturned, and now it seems obvious that, in fact, the Earth rotates on its axis and orbits the sun along with all the other planets, which explains our ‘perception’ that sometimes the planets go ‘backwards.’
 
I wonder if the next revolution in science and cosmology may also provide a ‘simpler’ picture, where there is a ‘universal now’ that explains the age of the Universe, the edge of time that we all experience and non-locality in QM.
 
Of course, I’m probably wrong.

Addendum: This is Richard Muller talking about time on Quora.

What we observe and what is reality are distinct in physics

 I’ve been doing this blog for 15 years now, and in that time some of my ideas have changed or evolved, and, in some areas, my knowledge has increased. As I’ve said on Quora a few times, I read a lot of books by people who know a lot more than me, especially in physics.
 
There is a boundary between physics and philosophy, the shoreline of John Wheeler’s metaphorical ‘island of knowledge in the infinite sea of ignorance’. To quote: “As the island grows so does the shoreline of our ignorance.” And I think ignorance is the key word here, because it’s basically speculation, which means some of us are wrong, including me, most likely. As I’ve often said, ‘Only future generations can tell us how ignorant the current generation is’. I can say that with a lot of confidence, just by looking at the history of science.
 
If this blog has a purpose beyond promoting my own pet theories and prejudices, it is to make people think.
 
Recently, I’ve been pre-occupied with determinism and something called superdeterminism, which has become one of those pet prejudices among physicists in the belief that it’s the only conclusion one can draw from combining relativity theory, quantum mechanics, entanglement and Bell’s theorem. Sabine Hossenfelder is one such advocate, who went so far as to predict that one day all other physicists will agree with her. I elaborate on this below.
 
Mark John Fernee (physicist with Qld Uni), with whom I’ve had some correspondence, is one who disagrees with her. I believe that John Bell himself proposed that superdeterminism was possibly the only resolution to the quandaries posed by his theorem. There are two other videos worth watching, one by Elijah Lew-Smith and a 50min one by Brian Greene, who doesn’t discuss superdeterminism. Nevertheless, Greene’s video gives the best and easiest to understand description of Bell’s theorem and its profound implications for reality.
 
So what is super-determinism, and how is it distinct from common or garden determinism? Well, if you watch the two relevant videos, you get two different answers. According to Sabine, there is no difference and it’s not really to do with Bell’s theorem, but with the measurement problem in QM. She argues that it’s best explained by looking at the double-slit experiment. Interestingly, Richard Feynman argued that all the problems associated with QM can be analysed, if not understood, by studying the double-slit experiment.
 
Sabine wrote an academic paper on the ‘measurement problem’, co-authored with Jonte R. Hance from the University of Bristol, which I’ve read and is surprisingly free of equations (not completely) but uses the odd term I’m unfamiliar with. I expect I was given a link by Fernee which I’ve since lost (I really can’t remember), but I still have a copy. One of her points is that as long as we have unsolved problems in QM, there is always room for different philosophical interpretations, and she and Hance discuss the most well-known ones. This is slightly off-topic, but only slightly, because even superdeterminism and its apparent elimination of free will is a philosophical issue.
 
Sabine argues that it’s the measurement that creates superdeterminism in QM, which is why she uses the double-slit experiment to demonstrate it. It’s because the ‘measurement’ ‘collapses’ the wave function and ‘determines’ the outcome, that it must have been ‘deterministic’ all along. It’s just that we don’t know it until a measurement is made. At least, this is my understanding of her argument.
 
The video by Elijah Lew-Smith gives a different explanation, focusing solely on Bell’s theorem. I found that it also required more than one viewing, but he makes a couple of points, which I believe go to the heart of the matter. (Greene’s video gives an easier-to-follow description, despite its length).
 
We can’t talk about an objective reality independent of measurement.
(Which echoes Sabine’s salient point in her video.)
 
And this point: There really are instantaneous interactions; we just can’t access them.
 
This is known as ‘non-locality’, and Brian Greene provides the best exposition I’ve seen, and explains how it’s central to Bell’s theorem and to our understanding of reality.
 
On the other hand, Lew-Smith explains non-locality without placing it at the centre of the discussion.
 
If I can momentarily go back to Sabine’s key argument, I addressed this in a post I wrote a few years back. Basically, I argued that you can only know the path an electron or photon takes retrospectively, after the measurement or observation has been made. Prior to that, QM tells us it’s in a superposition of states and we only have probabilities of where it will land. Curiously, I referenced a video by Sabine in a footnote, where she makes this point in her conclusion:
 
You don’t need to know what happens in the future because the particle goes to all points anyway. Except…  It doesn’t. In reality, it goes to only one point. So maybe the reason we need the measurement postulate is because we don’t take this dependency on the future seriously enough.
 
And to me, that’s what this is all about: the measurement is in the future of the wave function, and the path it takes is in the past. This, of course, is what Freeman Dyson claims: that QM cannot describe the past, only the future.
 
And if you combine this perspective with Lew-Smith’s comment about objective reality NOT being independent of the measurement, then objective reality only exists in the past, while the wave function and all its superpositional states exist in the future.
 
So how does entanglement fit into this? Well, this is the second point I highlighted, which is that ‘there really are instantaneous reactions, which we can’t access’, which is ‘non-locality’. And this, as Schrodinger himself proclaimed, is what distinguishes QM from classical physics. In classical physics, ‘locality’ means there is a relativistic causal connection and in entanglement there is not, which is why Einstein called it ‘spooky action at a distance’.
 
Bell’s theorem effectively tells us that non-locality is real, supported by experiment many times over, but you can’t use it to transmit information faster-than-light, so relativity is not violated in practical terms. But it does ask questions about simultaneity, which is discussed in Lew-Smith’s video. He demonstrates graphically that different observers will observe a different sequence of measurement, so we have disagreement, even a contradiction about which ‘measurement’ collapsed the wave function. And this is leads to superdeterminism, because, if the outcome is predetermined, then the sequence of measurement doesn’t matter.
 
And this gets to the nub of the issue, because it ‘appears’ that ‘objective reality’ is observer dependent. Relativity theory always gives the result from a specific observer’s point of view and different observers in different frames of reference can epistemically disagree. Is there a frame of reference that is observer independent? I always like to go back to the twin paradox, because I believe it provides an answer. When the twins reunite, they disagree on how much time has passed, yet they agree on where they are in space-time. There is not absolute time, but there is absolute space-time.
 
Did you know we can deduce the velocity that Earth travels relative to absolute space-time, meaning the overall observable Universe? By measuring the Doppler shift of the CMBR (cosmic microwave background radiation) in all directions, it’s been calculated that we are travelling at 350km/s in the direction of Pisces (ref., Paul Davies, About Time; Einstein’s Unfinished Revolution, 1995). They should teach this in schools.
 
Given this context, is it possible that entanglement is a manifestation of objective simultaneity? Not according to Einstein, who argued that: ‘The past, present and future is only a stubbornly persistent illusion’; which is based on the ‘fact’ that simultaneity is observer dependent. But Einstein didn’t live to see Bell’s theorem experimentally verified. Richard Muller, a prize-winning physicist and author (also on Quora) was asked what question he’d ask Einstein if he could hypothetically meet him NOW. I haven’t got a direct copy, but essentially Muller said he’d ask Einstein if he now accepted a ‘super-luminal connection’, given experimental confirmation of Bell’s theorem. In other words, entanglement is like an exception to the rule, where relativity strictly doesn’t apply.
 
Sabine with her co-author, Jonte Hance, make a passing comment that the discussion really hasn’t progressed much since Bohr and Einstein a century ago, and I think they have a point.
 
Mark Fernee, whom I keep mentioning on the sidelines, does make a distinction between determinism and superdeterminism, where determinism simply means that everything is causally connected to something, even if it’s not predictable. Chaos being a case-in-point, which he describes thus:
 
Where this determinism breaks down is with chaotic systems, such as three body dynamics. Chaotic systems are so sensitive to the initial parameters that even a slight inaccuracy can result in wildly different predictions. That's why predicting the weather is so difficult.
Overall, complexity limits the ability to predict the future, even in a causal universe.
 
On the other hand, superdeterminism effectively means the end of free will, and, in his own words, ‘free will is a contentious issue, even among physicists’.
 
Fernee provided a link to another document by Sabine, where she created an online forum specifically to deal with less than knowledgeable people about their disillusioned ideas on physics – crackpots and cranks. It occurred to me that I might fall into this category, but it’s for others to judge. I’m constantly reminded of how little I really know, and that I’m only fiddling around the edges, or on the ‘shoreline of ignorance’, as Wheeler described it, where there are many others far more qualified than me.
 
I not-so-recently wrote a post where I challenged a specific scenario often cited by physicists, where two observers hypothetically ‘observe’ contradictory outcomes of an event on a distant astronomical body that is supposedly happening simultaneously with them.
 
As I said before, relativity is an observer-dependent theory, almost by definition, and we know it works just by using the GPS on our smart-phones. There are algorithms that make relativistic corrections to the signals coming from the satellites, otherwise the map on your phone would not match the reality of your actual location.
 
What I challenge is the application of relativity theory to an event that the observer can’t observe, even in principle. In fact, relativity theory rules out a physical observation of a purportedly simultaneous event. So I’m not surprised that we get contradictory results. The accepted view among physicists is that each observer ‘sees’ a different ontology (one in the future and one in the past), whereas I contend that there is an agreed ontology that becomes observable at a later time, when it’s in both observers’ past. (Brian Greene has another video demonstrating the ‘conventional’ view among physicists.)
 
Claudia de Rahm is Professor of Physics at Imperial College London, and earlier this year, she gave a talk titled, What We Don’t Know About Gravity, where she made the revelatory point
that Einstein’s GR (general theory of relativity) predicted its own limitations. Basically, if you apply QM probabilities to extreme curvature spacetime, you get answers over 100%, so nonsense. GR and QM are mathematically incompatible if we try to quantise gravity, though QFT (quantum field theory) ‘works fine on the manifold of spacetime’, according to expert, Viktor T Toth.
 
Given that relativity theory, as it is applied, is intrinsically observer dependent, I question if it can be (reliably) applied to events that have no causal relation to the observer (meaning outside the observer's light cone, both past and future). Which is why I challenge its application to events the observer can't observe (refer 2 paragraphs ago).

 

Addendum: I changed the title so it's more consistent with the contents of the post. The previous title was Ignorance and bliss; philosophy and science. Basically, the reason we have different interpretations of the same phenomenon is because physics can only tell us about what we observe, and what that means for reality is often debatable; superdeterminism being a case in point. Many philosophers and scientists talk about a ‘gap’ between theory and reality, whereas I claim the gap is between the observation and reality, a la Kant.

An impossible thought experiment

I recently watched a discussion between Roger Penrose and Jordan Peterson, which was really a question and answer session, with Peterson asking the questions and Penrose providing the answers. There was a third person involved as moderator, but I’ve forgotten his name and his interaction was minimal. It was mostly about consciousness, but also touched on quantum mechanics and Godel’s theorem.

 

I can’t remember the context, but (at point 1.06) Penrose trotted out the well-worn thought experiment of 2 people crossing a street in opposite directions, and somewhere, in some far-flung part of the cosmos, an armada of spaceships is departing for a journey to Earth. Now, according to Einstein’s theory of relativity, one of these ‘observers’ will 'say' the fleet left 100s of years in the past and the other will 'say', no, they're leaving 100s of years in the future.

I’ve always had a problem with this ‘scenario’, and I’ve discussed it previously. The thing is that neither of them can ‘observe’ anything at all, because the ‘event’ (space fleet departing) is outside the light cone of influence of Earth (in either the future or the past). So neither of them receive a signal telling them that this is what they ‘observe’. In other words, it’s something they’ve worked out with equations or a space-time diagram. Brian Greene illustrates it graphically in a YouTube video.

 

Of course, my interpretation is considered ‘naïve’ and completely wrong by Penrose and every other physicist I know of.

 

Now, some thought experiments, like the famous EPR experiment, in combination with Bell’s Theorem, can be done in the real world, and was done after Einstein’s death and effectively proved Einstein wrong (on that particular point). Another example is John Wheeler’s delayed decision thought experiment for the double-slit experiment, which was also physically done after Wheeler’s death.

 

But this thought experiment is impossible to do, even in principle. My interpretation is that you have a clear contradiction, and where you have a contradiction there is usually something wrong with one or more of your premises. My proposed resolution is that what they 'perceive' is not reality, because the event is outside the cones-of-influence (past and future) of the observers.

But let’s take the thought experiment to its logical conclusion. Let’s say the observers record their deduced ‘time of departure’ with respect to their frame of reference, and it can be looked up centuries later when the fleet actually arrives on Earth. Now, when the fleet arrives, its trajectory through spacetime is within Earth’s past light cone. The fleet has its own time record of their journey and we know how far they’ve travelled. In fact, this is no different to the return leg of the famous twin paradox thought experiment. Now observers can apply relativistic corrections to the fleet’s recorded elapsed time, and deduce a time of departure based on Earth’s frame of reference. This will give a ‘time’ which I expect will fall somewhere between the 2 times recorded by the original observers.

 

Of course, this is still an impossible thought experiment because there is no way the 2 pedestrians could know when the fleet was departing. But if a fleet of spaceships did arrive on Earth from somewhere ‘far, far away’, we could calculate exactly when it left (ref. Earth time) and there would be no contradiction.

 

 

Footnote: I know that this stems from Einstein’s discovery that simultaneity varies according to an observer’s frame of reference, and there is an excellent video that explains the maths behind it. But here’s the thing: if the observer is equi-distant from the 2 signals in the same frame of reference you’ll get ‘true’ simultaneity (watch the video). On the other hand, an observer moving with respect to the sources will not see simultaneity. A little known fact is that you have to allow for length contraction as well as time dilation to get the right answer. But here’s another thing: on a cosmic scale, 2 observers can see 2 events in opposite sequence even if they’re not moving relative to each other. BUT, if the events have a causal relationship, then all observers see the same sequence, irrespective of relative motion. (Refer Addendum 2)*

 

 

Addendum 1: I’ve given this more thought, by having imaginary dialogue with a physicist, who would tell me that my ideas are inconsistent with relativity. Naturally, I would disagree with them. I would say it’s consistent with relativity, because, for the thought experiment to actually work would require instantaneous communication, which is as contradictory with relativity theory as one can get. For the 2 hypothetical observers to ‘know’ when the far-flung event took place would require them to observe it in their ‘now’, which is impossible. So my response is strictly a philosophical one: you can’t apply relativistic theory to this situation because the 'observation' would appear to 'violate' a tenet of relativity theory. And that’s because the event is outside the observers’ light cone. Am I missing something here? 

 

*Addendum 2: I watched a video by Sabine Hossenfelder, who addresses the last sentence in the footnote of this post. She says, in fact, that 2 events that have a causal relationship in our frame of reference could appear ‘independently’ simultaneous to ‘different’ observers in another part of the Universe (watch the video). This is a variation on the thought experiment that I discuss. In practice, because there’s no possible causal relationship between the events and the far-off observers, they wouldn’t observe anything. And it doesn’t change the sequence of causal events.

 

But she’s arguing that there are a multitude of ‘nows’, in accordance with one of Einstein’s premises that all observers have the same validity. That may be correct, but why does it apply to events they can’t even observe? To be fair to Sabine, she does try to address this at the end of the video. I’ve long argued that different observers see a different ‘now’, even without relativity, but if they see a different sequence of events, at least one of them has to be wrong.

 

I want to emphasise that I don’t think Einstein’s theories of relativity are wrong, as some people do. My point is purely a philosophical one: if you have a multitude of perspectives with different versions of events, they can’t all be right. I’m simply arguing that there is an objective reality. A case in point is the twin paradox, where one twin’s clock does run slower, irrespective of what each twin ‘observes’. Mark John Fernee gives a synoptic exposition here. As he says: they each have their own ‘true time’, and one is always slower.

 

If you go far enough into the future, where the events in question fall within the observer’s past light cone, then a history can be observed. We do this with the Universe itself, right back to the CMBR, 380,000 years after the Big Bang, which is 13.8 billion years ago; both of which we claim to know with some confidence.

 

I still maintain my core point, stated explicitly in the title of this post, that, as a hypothetical, the thought experiment described is impossible to do, simply because the event can’t be observed.

 

We are metaphysical animals

 I’m reading a book called Metaphysical Animals (How Four Women Brought Philosophy Back To Life). The four women were Mary Midgley, Iris Murdoch, Philippa Foot and Elizabeth Anscombe. The first two I’m acquainted with and the last two, not. They were all at Oxford during the War (WW2) at a time when women were barely tolerated in academia and had to be ‘chaperoned’ to attend lectures. Also a time when some women students ended up marrying their tutors. 

The book is authored by Clare Mac Cumhaill and Rachael Wiseman, both philosophy lecturers who became friends with Mary Midgley in her final years (Mary died in 2018, aged 99). The book is part biographical of all 4 women and part discussion of the philosophical ideas they explored.

 

Bringing ‘philosophy back to life’ is an allusion to the response (backlash is too strong a word) to the empiricism, logical positivism and general rejection of metaphysics that had taken hold of English philosophy, also known as analytical philosophy. Iris spent time in postwar Paris where she was heavily influenced by existentialism and Jean-Paul Sartre, in particular, whom she met and conversed with. 

 

If I was to categorise myself, I’m a combination of analytical philosopher and existentialist, which I suspect many would see as a contradiction. But this isn’t deliberate on my part – more a consequence of pursuing my interests, which are science on one hand (with a liberal dose of mathematical Platonism) and how-to-live a ‘good life’ (to paraphrase Aristotle) on the other.

 

Iris was intellectually seduced by Sartre’s exhortation: “Man is nothing else but that which he makes of himself”. But as her own love life fell apart along with all its inherent dreams and promises, she found putting Sartre’s implicit doctrine, of standing solitarily and independently of one’s milieu, difficult to do in practice. I’m not sure if Iris was already a budding novelist at this stage of her life, but anyone who writes fiction knows that this is what it’s all about: the protagonist sailing their lone ship on a sea full of icebergs and other vessels, all of which are outside their control. Life, like the best fiction, is an interaction between the individual and everyone else they meet. Your moral compass, in particular, is often tested. Existentialism can be seen as an attempt to arise above this, but most of us don’t. 

 

Not surprisingly, Wittgenstein looms large in many of the pages, and at least one of the women, Elizabeth Anscombe, had significant interaction with him. With Wittgenstein comes an emphasis on language, which has arguably determined the path of philosophy since. I’m not a scholar of Wittgenstein by any stretch of the imagination, but one thing he taught, or that people took from him, was that the meaning we give to words is a consequence of how they are used in ordinary discourse. Language requires a widespread consensus to actually work. It’s something we rarely think about but we all take for granted, otherwise there would be no social discourse or interaction at all. There is an assumption that when I write these words, they have the same meaning for you as they do for me, otherwise I am wasting my time.

 

But there is a way in which language is truly powerful, and I have done this myself. I can write a passage that creates a scene inside your mind complete with characters who interact and can cause you to laugh or cry, or pretty much any other emotion, as if you were present; as if you were in a dream.

 

There are a couple of specific examples in the book which illustrate Wittgenstein’s influence on Elizabeth and how she used them in debate. They are both topics I have discussed myself without knowing of these previous discourses.

 

In 1947, so just after the war, Elizabeth presented a paper to the Cambridge Moral Sciences Club, which she began with the following disclosure:

 

Everywhere in this paper I have imitated Dr Wittgenstein’s ideas and methods of discussion. The best that I have written is a weak copy of some features of the original, and its value depends only on my capacity to understand and use Dr Wittgenstein’s work.

 

The subject of her talk was whether one can truly talk about the past, which goes back to the pre-Socratic philosopher, Parmenides. In her own words, paraphrasing Parmenides, ‘To speak of something past’ would then to ‘point our thought’ at ‘something there’, but out of reach. Bringing Wittgenstein into the discussion, she claimed that Parmenides specific paradox about the past arose ‘from the way that thought and language connect to the world’.

 

We apply language to objects by naming them, but, in the case of the past, the objects no longer exist. She attempts to resolve this epistemological dilemma by discussing the nature of time as we experience it, which is like a series of pictures that move on a timeline while we stay in the present. This is analogous to my analysis that everything we observe becomes the past as soon as it happens, which is exemplified every time someone takes a photo, but we remain in the present – the time for us is always ‘now’.

 

She explains that the past is a collective recollection, documented in documents and photos, so it’s dependent on a shared memory. I would say that this is what separates our recollection of a real event from a dream, which is solipsistic and not shared with anyone else. But it doesn’t explain why the past appears fixed and the future unknown, which she also attempted to address. But I don’t think this can be addressed without discussing physics.

 

Most physicists will tell you that the asymmetry between the past and future can only be explained by the second law of thermodynamics, but I disagree. I think it is described, if not explained, by quantum mechanics (QM) where the future is probabilistic with an infinitude of possible paths and classical physics is a probability of ONE because it’s already happened and been ‘observed’. In QM, the wave function that gives the probabilities and superpositional states is NEVER observed. The alternative is that all the futures are realised in alternative universes. Of course, Elizabeth Anscombe would know nothing of these conjectures.

 

But I would make the point that language alone does not resolve this. Language can only describe these paradoxes and dilemmas but not explain them.

 

Of course, there is a psychological perspective to this, which many people claim, including physicists, gives the only sense of time passing. According to them, it’s fixed: past, present and future; and our minds create this distinction. I think our minds create the distinction because only consciousness creates a reference point for the present. Everything non-sentient is in a causal relationship that doesn’t sense time. Photons of light, for example, exist in zero time, yet they determine causality. Only light separates everything in time as well as space. I’ve gone off-topic.

 

Elizabeth touched on the psychological aspect, possibly unintentionally (I’ve never read her paper, so I could be wrong) that our memories of the past are actually imagined. We use the same part of the brain to imagine the past as we do to imagine the future, but again, Elizabeth wouldn’t have known this. Nevertheless, she understood that our (only) knowledge of the past is a thought that we turn into language in order to describe it.

 

The other point I wish to discuss is a famous debate she had with C.S. Lewis. This is quite something, because back then, C.S. Lewis was a formidable intellectual figure. Elizabeth’s challenge was all the more remarkable because Lewis’s argument appeared on the surface to be very sound. Lewis argued that the ‘naturalist’ position was self-refuting if it was dependent on ‘reason’, because reason by definition (not his terminology) is based on the premise of cause and effect and human reason has no cause. That’s a simplification, nevertheless it’s the gist of it. Elizabeth’s retort:

 

What I shall discuss is this argument’s central claim that a belief in the validity of reason is inconsistent with the idea that human thought can be fully explained as the product of non-rational causes.

 

In effect, she argued that reason is what humans do perfectly naturally, even if the underlying ‘cause’ is unknown. Not knowing the cause does not make the reasoning irrational nor unnatural. Elizabeth specifically cited the language that Lewis used. She accused him of confusing the concepts of “reason”, “cause” and “explanation”.

 

My argument would be subtly different. For a start, I would contend that by ‘reason’, he meant ‘logic’, because drawing conclusions based on cause and effect is logic, even if the causal relations (under consideration) are assumed or implied rather than observed. And here I contend that logic is not a ‘thing’ – it’s not an entity; it’s an action - something we do. In the modern age, machines perform logic; sometimes better than we do.

 

Secondly, I would ask Lewis, does he think reason only happens in humans and not other animals? I would contend that animals also use logic, though without language. I imagine they’d visualise their logic rather than express it in vocal calls. The difference with humans is that we can perform logic at a whole different level, but the underpinnings in our brains are surely the same. Elizabeth was right: not knowing its physical origins does not make it irrational; they are separate issues.

 

Elizabeth had a strong connection to Wittgenstein right up to his death. She worked with him on a translation and edit of Philosophical Investigations, and he bequeathed her a third of his estate and a third of his copyright.

 

It’s apparent from Iris’s diaries and other sources that Elizabeth and Iris fell in love at one point in their friendship, which caused them both a lot of angst and guilt because of their Catholicism. Despite marrying, Iris later had an affair with Pip (Philippa).

 

Despite my discussion of just 2 of Elizabeth’s arguments, I don’t have the level of erudition necessary to address most of the topics that these 4 philosophers published in. Just reading the 4 page Afterwards, it’s clear that I haven’t even brushed the surface of what they achieved. Nevertheless, I have a philosophical perspective that I think finds some resonance with their mutual ideas. 

 

I’ve consistently contended that the starting point for my philosophy is that for each of us individually, there is an inner and outer world. It even dictates the way I approach fiction. 

 

In the latest issue of Philosophy Now (Issue 149, April/May 2022), Richard Oxenberg, who teaches philosophy at Endicott College in Beverly, Massachusetts, wrote an article titled, What Is Truth? wherein he describes an interaction between 2 people, but only from a purely biological and mechanical perspective, and asks, ‘What is missing?’ Well, even though he doesn’t spell it out, what is missing is the emotional aspect. Our inner world is dominated by emotional content and one suspects that this is not unique to humans. I’m pretty sure that other creatures feel emotions like fear, affection and attachment. What’s more I contend that this is what separates, not just us, but the majority of the animal kingdom, from artificial intelligence.

 

But humans are unique, even among other creatures, in our ability to create an inner world every bit as rich as the one we inhabit. And this creates a dichotomy that is reflected in our division of arts and science. There is a passage on page 230 (where the authors discuss R.G. Collingwood’s influence on Mary), and provide an unexpected definition.

 

Poetry, art, religion, history, literature and comedy are all metaphysical tools. They are how metaphysical animals explore, discover and describe what is real (and beautiful and good). (My emphasis.)

 

I thought this summed up what they mean with their coinage, metaphysical animals, which titles the book, and arguably describes humanity’s most unique quality. Descriptions of metaphysics vary and elude precise definition but the word, ‘transcendent’, comes to mind. By which I mean it’s knowledge or experience that transcends the physical world and is most evident in art, music and storytelling, but also includes mathematics in my Platonic worldview.

 

Footnote: I should point out that certain chapters in the book give considerable emphasis to moral philosophy, which I haven’t even touched on, so another reader might well discuss other perspectives.