Posts Tagged ‘reality’
“Few people have the imagination for reality”*…
Experiments that test physics and philosophy as “a single whole,” Amanda Gefter suggests, may be our only route to surefire knowledge about the universe…
Metaphysics is the branch of philosophy that deals in the deep scaffolding of the world: the nature of space, time, causation and existence, the foundations of reality itself. It’s generally considered untestable, since metaphysical assumptions underlie all our efforts to conduct tests and interpret results. Those assumptions usually go unspoken.
Most of the time, that’s fine. Intuitions we have about the way the world works rarely conflict with our everyday experience. At speeds far slower than the speed of light or at scales far larger than the quantum one, we can, for instance, assume that objects have definite features independent of our measurements, that we all share a universal space and time, that a fact for one of us is a fact for all. As long as our philosophy works, it lurks undetected in the background, leading us to mistakenly believe that science is something separable from metaphysics.
But at the uncharted edges of experience — at high speeds and tiny scales — those intuitions cease to serve us, making it impossible for us to do science without confronting our philosophical assumptions head-on. Suddenly we find ourselves in a place where science and philosophy can no longer be neatly distinguished. A place, according to the physicist Eric Cavalcanti, called “experimental metaphysics.”
Cavalcanti is carrying the torch of a tradition that stretches back through a long line of rebellious thinkers who have resisted the usual dividing lines between physics and philosophy. In experimental metaphysics, the tools of science can be used to test our philosophical worldviews, which in turn can be used to better understand science. Cavalcanti, a 46-year-old native of Brazil who is a professor at Griffith University in Brisbane, Australia, and his colleagues have published the strongest result attained in experimental metaphysics yet, a theorem that places strict and surprising constraints on the nature of reality. They’re now designing clever, if controversial, experiments to test our assumptions not only about physics, but about the mind.
While we might expect the injection of philosophy into science to result in something less scientific, in fact, says Cavalcanti, the opposite is true. “In some sense, the knowledge that we obtain through experimental metaphysics is more secure and more scientific,” he said, because it vets not only our scientific hypotheses but the premises that usually lie hidden beneath…
Gefter traces the history of this integrative train of thought (Kant, Duhem, Poincaré, Popper, Einstein, Bell), its potential for helping understand quantum theory… and the prospect of harnessing AI to run the necessary experiments– seemingly comlex and intensive beyond the scope of currenT experimental techniques…
Cavalcanti… is holding out hope. We may never be able to run the experiment on a human, he says, but why not an artificial intelligence algorithm? In his newest work, along with the physicist Howard Wiseman and the mathematician Eleanor Rieffel, he argues that the friend could be an AI algorithm running on a large quantum computer, performing a simulated experiment in a simulated lab. “At some point,” Cavalcanti contends, “we’ll have artificial intelligence that will be essentially indistinguishable from humans as far as cognitive abilities are concerned,” and we’ll be able to test his inequality once and for all.
But that’s not an uncontroversial assumption. Some philosophers of mind believe in the possibility of strong AI, but certainly not all. Thinkers in what’s known as embodied cognition, for instance, argue against the notion of a disembodied mind, while the enactive approach to cognition grants minds only to living creatures.
All of which leaves physics in an awkward position. We can’t know whether nature violates Cavalcanti’s [theorem] — we can’t know, that is, whether objectivity itself is on the metaphysical chopping block — until we can define what counts as an observer, and figuring that out involves physics, cognitive science and philosophy. The radical space of experimental metaphysics expands to entwine all three of them. To paraphrase Gonseth, perhaps they form a single whole…
“‘Metaphysical Experiments’ Probe Our Hidden Assumptions About Reality,” in @QuantaMagazine.
* Johann Wolfgang von Goethe
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As we examine edges, we might send thoughtful birthday greetings to Rudolf Schottlaender; he was born on this date in 1900. A philosopher who studied with Edmund Husserl, Martin Heidegger, Nicolai Hartmann, and Karl Jaspers, Schottlaender survived the Nazi regime and the persecution of the Jews, hiding in Berlin. After the war, as his democratic and humanist proclivities kept him from posts in philosophy faculties, he distinguished himself as a classical philologist and translator (e.g., new translations of Sophocles which were very effective on the stage, and an edition of Petrarch).
But he continued to publish philosophical and political essays and articles, which he predominantly published in the West and in which he saw himself as a mediator between the systems. Because of his positions critical to East Germany, he was put under close surveillance by the Ministry for State Security (Ministerium für Staatssicherheit or Stasi)– and inspired leading minds of the developing opposition in East Germany.
“Reality is merely an illusion, albeit a very persistent one”*…
In an excerpt from his new book, The Rigor of Angels: Borges, Heisenberg, Kant, and the Ultimate Nature of Reality, the estimable William Egginton explains the central mystery at the heart of one of the most important breakthroughs in physics–quantum mechanics…
For all its astonishing, mind-bending complexity– for all its blurry cats, entangled particles, buckyballs, and Bell’s inequalities– quantum mechanics ultimately boils down to one core mystery. This mystery found its best expression in the letter Heisenberg wrote to Pauli in the fevered throes of his discovery. The path a particle takes ‘only comes into existence through this, that we observe it.’ This single, stunning expression underlies all the rest: the wave/particle duality (interference patterns emerge when the particles have not yet been observed and hence their possible paths interfere with one another); the apparently absurd liminal state of Schrodinger’s cat ( the cat seems to remain blurred between life and death because atoms don’t release a particle until observed); the temporal paradox (observing a particle seems to retroactively determine the path it chose to get here); and, the one that really got to Einstein, if the observation of a particle at one place and time instantaneously changes something about the rest of reality, then locality, the cornerstone of relativity and guarantee that the laws of physics are invariable through the universe, vanishes like fog on a warming windowpane.
If the act of observation somehow instantaneously conjures a particle’s path, the foundations not only of classical physics but also of what we widely regard as physical reality crumble before our eyes. This fact explains why Einstein held fast to another interpretation. The particle’s path doesn’t come into existence when we observe it. The path exists, but we just can’t see it. Like the parable of the ball in the box he described in his letter to Schrodinger, a 50 percent chance of finding a ball in any one of two boxes does not complete the description of the ball’s reality before we open the box. It merely states our lack of knowledge about the ball’s whereabouts.
And yet, as experiment after experiment has proven, the balls simply aren’t there before the observation. We can separate entangled particles, seemingly to any conceivable distance, and by observing one simultaneously come to know something about the other–something that wasn’t the case until the exact moment of observing it. Like the beer and whiskey twins, we can maintain total randomness up to a nanosecond before one of them orders, and still what the one decides to order will determine the other’s drink, on the spot, even light-years away.
The ineluctable fact of entanglement tells us something profound about reality and our relation to it. Imagine you are one of the twins about to order a drink (this should be more imaginable than being an entangled particle about to be observed, but the idea is the same). From your perspective you can order either a whiskey or a beer: it’s a fifty-fifty choice; nothing is forcing your hand. Unbeknownst to you, however, in a galaxy far, far away, your twin has just made the choice for you. Your twin can’t tell you this or signal it in any way, but what you perceive to be a perfectly random set of possibilities, an open choice, is entirely constrained. You have no idea if you will order beer or whiskey, but when you order it, it will be the one or the other all the same. If your twin is, say, one light-year away, the time in which you make this decision doesn’t even exist over there yet. Any signals your sibling gets from you, or any signals you send, will take another year to arrive. And still, as of this moment, you each know. Neither will get confirmation for another year, but you can be confident, you can bet your life’s savings on it–a random coin toss in another galaxy, and you already know the outcome.
The riddles that arise from Heisenberg’s starting point would seem to constitute the most vital questions of existence. And yet one of the curious side effects of quantum mechanics’ extraordinary success has been a kind of quietism in the face of those very questions. The interpretation of quantum mechanics, deciding what all this means, has tended to go unnoticed by serious physics departments and the granting agencies that support them in favor of the ‘shut up and calculate’ school, leading the former to take hold mainly in philosophy departments, as a subfield of the philosophy of science called foundations of physics. Nevertheless, despite such siloing, a few physicists persisted in exploring possible solutions to the quantum riddles. Some of their ideas have been literally otherworldly.
In the 1950s, a small group of graduate students working with John Wheeler at Princeton University became fascinated with these problems and kept returning to them in late-night, sherry-fueled rap sessions. Chief among this group was Hugh Everett III, a young man with classic 1950s-style nerd glasses and a looming forehead. Everett found himself chafing at the growing no-question zone that proponents of the Copenhagen interpretation had built around their science. Why should we accept that in one quantum reality, observations somehow cause nature to take shape out of a probabilistic range of options, whereas on this side of some arbitrary line in the sand we inhabit a different, classical reality where observations meekly bow to the world out there? What exactly determines when this change takes place? ‘Let me mention a few more irritating features of the Copenhagen Interpretation,’ Everett would write to its proponents: ‘You talk of the massiveness of macro systems allowing one to neglect further quantum effects … but never give any justification for this flatly asserted dogma.’…
A fascinating sample of a fascinating book: “Quantum Mechanics,” from @WilliamEgginton via the invaluable @delanceyplace.
Further to which, it’s interesting to recall that, in his 1921 The Analysis Of Mind, Bertrand Russell observed:
What has permanent value in the outlook of the behaviourists is the feeling that physics is the most fundamental science at present in existence. But this position cannot be called materialistic, if, as seems to be the case, physics does not assume the existence of matter…
via Robert Cottrell
See also: “Objective Reality May Not Exist, Quantum Experiment Suggests” (source of the image above).
* Albert Einstein
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As we examine existence, we might spare a thought for Otto Frisch; he died on this date in 1979. A physicist, he was (with Otto Stern and Immanuel Estermann) the first to measure the magnetic moment of the proton. With his aunt, Lise Meitner, he advanced the first theoretical explanation of nuclear fission (coining the term) and first experimentally detected the fission by-products. Later, with his collaborator Rudolf Peierls, he designed the first theoretical mechanism for the detonation of an atomic bomb in 1940.
“He offered alternative facts”*…
When reach exceeds grasp (in both senses of the word), from @ryanqnorth in Dinosaur Comics.
* Kellyanne Conway (defending Sean Spicer)
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As we have it our way, we might we might send an amusing birthday verse to Ogden Nash; he was born on this date in 1902. A poet best known for his light verse, Nash wrote over 500 pieces published, between 1931 and 1972, in 14 volumes. At the time of his death in 1971, he was, The New York Times averred, “the country’s best-known producer of humorous poetry.” The following year, on his birthday, the U.S. Postal service celebrated him with a commemorative stamp.
- Candy
Is Dandy
But liquor
Is quicker.- “Reflections on Ice-Breaking” in Hard Lines (1931); often misattributed to Dorothy Parker
- It is common knowledge to every schoolboy and even every Bachelor of Arts,
That all sin is divided into two parts.
One kind of sin is called a sin of commission, and that is very important
And it is what you are doing when you are doing something you ortant…- “Portrait of the Artist as a Prematurely Old Man” in The Family Album of Favorite Poems (1959)
“‘Space-time’ – that hideous hybrid whose very hyphen looks phoney”*…
Space and time seem about as basic as anything could be, even after Einstein’s theory of General Relativity threw (in) a curve. But as Steven Strogatz discusses with Sean Carroll, the reconciliation of Einstein’s work with quantum theory is seeming to suggest that space and time might actually be emergent properties of quantum reality, not fundamental parts of it…
… we’re going to be discussing the mysteries of space and time, and gravity, too. What’s so mysterious about them?
Well, it turns out they get really weird when we look at them at their deepest levels, at a super subatomic scale, where the quantum nature of gravity starts to kick in and become crucial. Of course, none of us have any direct experience with space and time and gravity at this unbelievably small scale. Up here, at the scale of everyday life, space and time seem perfectly smooth and continuous. And gravity is very well described by Isaac Newton’s classic theory, a theory that’s been around for over 300 years now.
But then, about 100 years ago, things started to get strange. Albert Einstein taught us that space and time could warp and bend like a piece of fabric. This warping of the space-time continuum is what we experience as gravity. But Einstein’s theory is mainly concerned with the largest scales of nature, the scale of stars, galaxies and the whole universe. It doesn’t really have much to say about space and time at the very smallest scales.
And that’s where the trouble really starts. Down there, nature is governed by quantum mechanics. This amazingly powerful theory has been shown to account for all the forces of nature, except gravity. When physicists try to apply quantum theory to gravity, they find that space and time become almost unrecognizable. They seem to start fluctuating wildly. It’s almost like space and time fall apart. Their smoothness breaks down completely, and that’s totally incompatible with the picture in Einstein’s theory.
s physicists try to make sense of all of this, some of them are coming to the conclusion that space and time may not be as fundamental as we always imagined. They’re starting to seem more like byproducts of something even deeper, something unfamiliar and quantum mechanical. But what could that something be?….
Find out at: “Where Do Space, Time and Gravity Come From?, ” from @stevenstrogatz and @seanmcarroll in @QuantaMagazine.
* Vladimir Nabokov
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As we fumble with the fundamental, we might send far-sighted birthday greetings to Jocelyn Bell Burnell; she was born on this date in 1943. An astrophysicist, she discovered the first pulsar, while working as a post-doc, in 1957. She then discovered the next three detected pulsars.
The discovery eventually earned the Nobel Prize in Physics in 1974; however, she was not one of the prize’s recipients. The paper announcing the discovery of pulsars had five authors. Bell’s thesis supervisor Antony Hewish was listed first, Bell second. Hewish was awarded the Nobel Prize, along with the astronomer Martin Ryle.
A pulsar— or pulsating radio star– a highly magnetized, rotating neutron star that emits a beam of electromagnetic radiation. The precise periods of pulsars make them very useful tools. Observations of a pulsar in a binary neutron star system were used to confirm (indirectly) the existence of gravitational radiation. The first extrasolar planets were discovered around a pulsar, PSR B1257+12. And certain types of pulsars rival atomic clocks in their accuracy in keeping time.
“The truth is rarely pure and never simple”*…
For a century, the idea of truth has been deflated, becoming terrain from which philosophers fled. Crispin Sartwell argues that they must return – urgently…
It is often said, rather casually, that truth is dissolving, that we live in the ‘post-truth era’. But truth is one of our central concepts – perhaps our most central concept – and I don’t think we can do without it. To believe that masks prevent the spread of COVID-19 is to take it to be true that they do. To assert it is to claim that it is true. Truth is, plausibly, central to thought and communication in every case. And, of course, it’s often at stake in practical political debates and policy decisions, with regard to climate change or vaccines, for example, or who really won the election, or whom we should listen to about what.
One might have hoped to turn to philosophy for a clarification of the nature of truth, and maybe even a celebration of it. But philosophy of pragmatist, analytic and continental varieties lurched into the post-truth era a century ago. If truth is a problem now for everyone, if the idea seems empty or useless in ‘the era of social media’, ‘science denialism’, ‘conspiracy theories’ and suchlike, maybe that just means that ‘everyone’ has caught up to where philosophy was in 1922…
[Sartwell sketches the last 100 years of philosophy, and it’s undermining of the very idea of truth.]
I don’t think, despite all the attacks on the notion by all sorts of philosophers for a good century, that we’re going to be able to do without truth. In a way, I don’t think all those attacks touched truth at all, which (we’re finding) is necessary, still the only possible cure…
As a first step… we might broaden the focus from the philosophical question of what makes a sentence or proposition true or false to focus on some of the rich ways the concept of truth functions in our discourse. That love is true does not mean that it is a representation that matches up to reality. It does not mean that the love hangs together with all the rest of the lover or lovee’s belief system. It doesn’t mean that the hypothesis that my love is true helps us resolve our problems (it might introduce more problems). It means that the love is intense and authentic, or, as I’d like to put it, that it is actual, real. That my aim is true does not indicate that my aim accurately pictures the external world, but that it thumps the actual world right in the centre, as it were.
Perhaps what is true or false isn’t only, or even primarily, propositions, but loves and aims, and the world itself. That is, I would like to start out by thinking of ‘true’ as a semi-synonym of ‘real’. If I were formulating in parallel to Aristotle, I might say that ‘What is, is true.’ And perhaps there’s something to be said for Heidegger’s ‘comportment’ after all: to know and speak the real requires a certain sort of commitment: a commitment to face reality. Failures of truth are, often, failures to face up. Now, I’m not sure how much that will help with mathematics, but maths needs to understand that it is only one among the many forms of human knowledge. We, or at any rate I, might hope that an account that addresses the traditional questions about propositional truth might emerge from this broader structure of understanding. That is speculative, I admit.
Truth may not be the eternal unchanging Form that Plato thought it was, but that doesn’t mean it can be destroyed by a few malevolent politicians, tech moguls or linguistic philosophers, though the tech moguls and some of the philosophers (David Chalmers, for instance) might be trying to undermine or invent reality, as well. Until they manage it, the question of truth is as urgent, or more urgent, than ever, and I would say that despite the difficulties, philosophers need to take another crack. Perhaps not at aletheia as a joy forever, but at truth as we find it, and need it, now…
On why philosophy needs to return of the question of truth: “Truth Is Real,” from @CrispinSartwell in @aeonmag.
Source of the image above, also relevant: “The difference between ‘Truth’ and ‘truth’.”
* Oscar Wilde
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As we wrestle with reality, we might recall that it was on this date in 1986 that Geraldo Rivera opened “Al Capone’s Vault”…
Notorious and “most wanted” gangster, Al Capone, began his life of crime in Chicago in 1919 and had his headquarters set up at the Lexington Hotel until his arrest in 1931. Years later, renovations were being made at the hotel when a team of workers discovered a shooting-range and series of connected tunnels that led to taverns and brothels making for an easy escape should there be a police raid. Rumors were spread that Capone had a secret vault hidden under the hotel as well. In 1985, news reporter Geraldo Rivera had been fired from ABC after he criticized the network for canceling his report made about an alleged relationship between John F. Kennedy and Marilyn Monroe. It seemed like a good time for Rivera to scoop a new story to repair his reputation. It was on this day in 1986 that his live, two-hour, syndicated TV special, The Mystery of Al Capone’s Vault aired. After lots of backstory, the time finally came to reveal what was in that vault. It turned out to be empty. After the show, Rivera was quoted as saying “Seems like we struck out.”
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