SCIENCE – physics

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SCIENCE natural, physics, quantum – consciousness, self, agency – philosophy of

backreaction.blog 28-9-2022 I’ve said it all before but here we go again – For reasons I don’t fully understand, particle physicists have recently started picking on me again for allegedly being hostile, and have been coming at me with their usual ad homimen attacks – by Sabine Hossenfelder

theguardian.com 25-9-2022 No one in physics dares say so, but the race to invent new particles is pointless – In private, many physicists admit they do not believe the particles they are paid to search for exist – they do it because their colleagues are doing it – by Sabine Hossenfelder



newscientist.com 2019 The quantum world is infamously weird – now we might know why
The property that makes the subatomic realm so odd could also be the engine that gives quantum computers their superpower – In a notable interdisciplinary book, Matthieu Ricard and Trinh Xuan Thuan claim that there are “many ways in which science and Buddhism confirm and complement each other…” (The Quantum and the Lotus, 2001, 2004). You especially see this pattern in the quantum mechanics that underlie quantum information technology. The latter is being used “…to develop new kinds of computers and communications networks, and sensors for imaging and measuring things in novel ways” (Jeanne Whalen, “Seven Basic Questions About Quantum Technology, Answered,” The Washington Post, August 18, 2019). – by Ciarán Gilligan-Lee


https://www.newscientist.com/article/2272400-has-the-large-hadron-collider-finally-challenged-the-laws-of-physics/


standard.co.uk 3/2021 ‘Intriguing’ results from Cern challenge leading theory in physics
Physicists have found particles not behaving in the way they should according to the Standard Model.


the times.co.uk 25/3/2021 Cern’s naughty quarks chip away at standard physics


standard.co.uk 23/3/2021 Helgoland by Carlo Rovelli review – the mysteries of quantum mechanics – Having altered how we think about time, the physicist sets his sights on perhaps the most maddeningly difficult theory of all by Ian Thomson

Carlo Rovelli, the Italian theoretical physicist, is one of the great scientific explicators of our time. His wafer-thin essay collection, Seven Brief Lessons on Physics, sold more than 1m copies in English translation in 2015 and remains the world’s fastest-selling science book. In The Order of Time and Reality Is Not What It Seems, Rovelli illuminated the disquieting uncertainties of Einsteinian relativity, gravitational waves and other tentative physics. Nobody said that post-Newtonian physics was easy, but Rovelli’s gift is to bring difficult ideas down a level. His books continue a tradition of jargon-free popular scientific writing from Galileo to Darwin that disappeared in the academic specialisations of the past century. Only in recent years has science become, in publishing terms, popular and attractive again. Rovelli’s new book, Helgoland, attempts to explain the maddeningly difficult theory of quantum mechanics.


 



.theguardian.com/ 4/2021  A growing chorus of scientists and philosophers argue that free will does not exist. Could they be right?  by Oliver Burkeman

 …”Towards the end of a conversation dwelling on some of the deepest metaphysical puzzles regarding the nature of human existence, the philosopher Galen Strawson paused, then asked me: “Have you spoken to anyone else yet who’s received weird email?” He navigated to a file on his computer and began reading from the alarming messages he and several other scholars had received over the past few years. Some were plaintive, others abusive, but all were fiercely accusatory. “Last year you all played a part in destroying my life,” one person wrote. “I lost everything because of you – my son, my partner, my job, my home, my mental health. All because of you, you told me I had no control, how I was not responsible for anything I do, how my beautiful six-year-old son was not responsible for what he did … Goodbye, and good luck with the rest of your cancerous, evil, pathetic existence.” “Rot in your own shit Galen,” read another note, sent in early 2015. “Your wife, your kids your friends, you have smeared all there [sic] achievements you utter fucking prick,” wrote the same person, who subsequently warned: “I’m going to fuck you up.” And then, days later, under the subject line “Hello”: “I’m coming for you.” “This was one where we had to involve the police,” Strawson said. Thereafter, the violent threats ceased. …

Given how watertight the case against free will can appear, it may be surprising to learn that most philosophers reject it: according to a 2009 survey, conducted by the website PhilPapers, only about 12% of them are persuaded by it. And the disagreement can be fraught, partly because free will denial belongs to a wider trend that drives some philosophers spare – the tendency for those trained in the hard sciences to make sweeping pronouncements about debates that have raged in philosophy for years, as if all those dull-witted scholars were just waiting for the physicists and neuroscientists to show up. In one chilly exchange, Dennett paid a backhanded compliment to Harris, who has a PhD in neuroscience, calling his book “remarkable” and “valuable” – but only because it was riddled with so many wrongheaded claims: “I am grateful to Harris for saying, so boldly and clearly, what less outgoing scientists are thinking but keeping to themselves.”

What’s still more surprising, and hard to wrap one’s mind around, is that most of those who defend free will don’t reject the sceptics’ most dizzying assertion – that every choice you ever make might have been determined in advance. So in the fruit bowl example, a majority of philosophers agree that if you rewound the tape of history to the moment of choice, with everything in the universe exactly the same, you couldn’t have made a different selection. That kind of free will is “as illusory as poltergeists”, to quote Dennett. What they claim instead is that this doesn’t matter: that even though our choices may be determined, it makes sense to say we’re free to choose. That’s why they’re known as “compatibilists”: they think determinism and free will are compatible. (There are many other positions in the debate, including some philosophers, many Christians among them, who think we really do have “ghostly” free will; and others who think the whole so-called problem is a chimera, resulting from a confusion of categories, or errors of language.)

To those who find the case against free will persuasive, compatibilism seems outrageous at first glance. How can we possibly be free to choose if we aren’t, in fact, you know, free to choose? But to grasp the compatibilists’ point, it helps first to think about free will not as a kind of magic, but as a mundane sort of skill – one which most adults possess, most of the time. As the compatibilist Kadri Vihvelin writes, “we have the free will we think we have, including the freedom of action we think we have … by having some bundle of abilities and being in the right kind of surroundings.” The way most compatibilists see things, “being free” is just a matter of having the capacity to think about what you want, reflect on your desires, then act on them and sometimes get what you want. When you choose the banana in the normal way – by thinking about which fruit you’d like, then taking it – you’re clearly in a different situation from someone who picks the banana because a fruit-obsessed gunman is holding a pistol to their head; or someone afflicted by a banana addiction, compelled to grab every one they see. In all of these scenarios, to be sure, your actions belonged to an unbroken chain of causes, stretching back to the dawn of time. But who cares? The banana-chooser in one of them was clearly more free than in the others.

“Harris, Pinker, Coyne – all these scientists, they all make the same two-step move,” said Eddy Nahmias, a compatibilist philosopher at Georgia State University in the US. “Their first move is always to say, ‘well, here’s what free will means’” – and it’s always something nobody could ever actually have, in the reality in which we live. “And then, sure enough, they deflate it. But once you have that sort of balloon in front of you, it’s very easy to deflate it, because any naturalistic account of the world will show that it’s false.”

Daniel Dennett in Stockholm, Sweden.
Daniel Dennett in Stockholm, Sweden. Photograph: Ibl/Rex/Shutterstock

Consider hypnosis. A doctrinaire free will sceptic might feel obliged to argue that a person hypnotised into making a particular purchase is no less free than someone who thinks about it, in the usual manner, before reaching for their credit card. After all, their idea of free will requires that the choice wasn’t fully determined by prior causes; yet in both cases, hypnotised and non-hypnotised, it was. “But come on, that’s just really annoying,” said Helen Beebee, a philosopher at the University of Manchester who has written widely on free will, expressing an exasperation commonly felt by compatibilists toward their rivals’ more outlandish claims. “In some sense, I don’t care if you call it ‘free will’ or ‘acting freely’ or anything else – it’s just that it obviously does matter, to everybody, whether they get hypnotised into doing things or not.”

Granted, the compatibilist version of free will may be less exciting. But it doesn’t follow that it’s worthless. Indeed, it may be (in another of Dennett’s phrases) the only kind of “free will worth wanting”. You experience the desire for a certain fruit, you act on it, and you get the fruit, with no external gunmen or internal disorders influencing your choice. How could a person ever be freer than that?

Thinking of free will this way also puts a different spin on some notorious experiments conducted in the 80s by the American neuroscientist Benjamin Libet, which have been interpreted as offering scientific proof that free will doesn’t exist. Wiring his subjects to a brain scanner, and asking them to flex their hands at a moment of their choosing, Libet seemed to show that their choice was detectable from brain activity 300 milliseconds before they made a conscious decision. (Other studies have indicated activity up to 10 seconds before a conscious choice.) How could these subjects be said to have reached their decisions freely, if the lab equipment knew their decisions so far in advance? But to most compatibilists, this is a fuss about nothing. Like everything else, our conscious choices are links in a causal chain of neural processes, so of course some brain activity precedes the moment at which we become aware of them.

From this down-to-earth perspective, there’s also no need to start panicking that cases like Charles Whitman’s might mean we could never hold anybody responsible for their misdeeds, or praise them for their achievements. (In their defence, several free will sceptics I spoke to had their reasons for not going that far, either.) Instead, we need only ask whether someone had the normal ability to choose rationally, reflecting on the implications of their actions. We all agree that newborn babies haven’t developed that yet, so we don’t blame them for waking us in the night; and we believe most non-human animals don’t possess it – so few of us rage indignantly at wasps for stinging us. Someone with a severe neurological or developmental impairment would surely lack it, too, perhaps including Whitman. But as for everyone else: “Bernie Madoff is the example I always like to use,” said Nahmias. “Because it’s so clear that he knew what he was doing, and that he knew that what he was doing was wrong, and he did it anyway.” He did have the ability we call “free will” – and used it to defraud his investors of more than $17bn.

To the free will sceptics, this is all just a desperate attempt at face-saving and changing the subject – an effort to redefine free will not as the thing we all feel, when faced with a choice, but as something else, unworthy of the name. “People hate the idea that they aren’t agents who can make free choices,” Jerry Coyne has argued. Harris has accused Dennett of approaching the topic as if he were telling someone bent on discovering the lost city of Atlantis that they ought to be satisfied with a trip to Sicily. After all, it meets some of the criteria: it’s an island in the sea, home to a civilisation with ancient roots. But the facts remain: Atlantis doesn’t exist. And when it felt like it wasn’t inevitable you’d choose the banana, the truth is that it actually was.


It’s tempting to dismiss the free will controversy as irrelevant to real life, on the grounds that we can’t help but feel as though we have free will, whatever the philosophical truth may be. I’m certainly going to keep responding to others as though they had free will: if you injure me, or someone I love, I can guarantee I’m going to be furious, instead of smiling indulgently on the grounds that you had no option. In this experiential sense, free will just seems to be a given.

But is it? When my mind is at its quietest – for example, drinking coffee early in the morning, before the four-year-old wakes up – things are liable to feel different. In such moments of relaxed concentration, it seems clear to me that my intentions and choices, like all my other thoughts and emotions, arise unbidden in my awareness. There’s no sense in which it feels like I’m their author. Why do I put down my coffee mug and head to the shower at the exact moment I do so? Because the intention to do so pops up, caused, no doubt, by all sorts of activity in my brain – but activity that lies outside my understanding, let alone my command. And it’s exactly the same when it comes to those weightier decisions that seem to express something profound about the kind of person I am: whether to attend the funeral of a certain relative, say, or which of two incompatible career opportunities to pursue. I can spend hours or even days engaged in what I tell myself is “reaching a decision” about those, when what I’m really doing, if I’m honest, is just vacillating between options – until at some unpredictable moment, or when an external deadline forces the issue, the decision to commit to one path or another simply arises.

This is what Harris means when he declares that, on close inspection, it’s not merely that free will is an illusion, but that the illusion of free will is itself an illusion: watch yourself closely, and you don’t even seem to be free. “If one pays sufficient attention,” he told me by email, “one can notice that there’s no subject in the middle of experience – there is only experience. And everything we experience simply arises on its own.” This is an idea with roots in Buddhism, and echoed by others, including the philosopher David Hume: when you look within, there’s no trace of an internal commanding officer, autonomously issuing decisions. There’s only mental activity, flowing on. Or as Arthur Rimbaud wrote, in a letter to a friend in 1871: “I am a spectator at the unfolding of my thought; I watch it, I listen to it.”

There are reasons to agree with Saul Smilansky that it might be personally and societally detrimental for too many people to start thinking in this way, even if it turns out it’s the truth. (Dennett, although he thinks we do have free will, takes a similar position, arguing that it’s morally irresponsible to promote free-will denial.) In one set of studies in 2008, the psychologists Kathleen Vohs and Jonathan Schooler asked one group of participants to read an excerpt from The Astonishing Hypothesis by Francis Crick, co-discoverer of the structure of DNA, in which he suggests free will is an illusion. The subjects thus primed to doubt the existence of free will proved significantly likelier than others, in a subsequent stage of the experiment, to cheat in a test where there was money at stake. Other research has reported a diminished belief in free will to less willingness to volunteer to help others, to lower levels of commitment in relationships, and lower levels of gratitude.

Unsuccessful attempts to replicate Vohs and Schooler’s findings have called them into question. But even if the effects are real, some free will sceptics argue that the participants in such studies are making a common mistake – and one that might get cleared up rather rapidly, were the case against free will to become better known and understood. Study participants who suddenly become immoral seem to be confusing determinism with fatalism – the idea that if we don’t have free will, then our choices don’t really matter, so we might as well not bother trying to make good ones, and just do as we please instead. But in fact it doesn’t follow from our choices being determined that they don’t matter. It might matter enormously whether you choose to feed your children a diet rich in vegetables or not; or whether you decide to check carefully in both directions before crossing a busy road. It’s just that (according to the sceptics) you don’t get to make those choices freely.

In any case, were free will really to be shown to be nonexistent, the implications might not be entirely negative. It’s true that there’s something repellent about an idea that seems to require us to treat a cold-blooded murderer as not responsible for his actions, while at the same time characterising the love of a parent for a child as nothing more than what Smilansky calls “the unfolding of the given” – mere blind causation, devoid of any human spark. But there’s something liberating about it, too. It’s a reason to be gentler with yourself, and with others. For those of us prone to being hard on ourselves, it’s therapeutic to keep in the back of your mind the thought that you might be doing precisely as well as you were always going to be doing – that in the profoundest sense, you couldn’t have done any more. And for those of us prone to raging at others for their minor misdeeds, it’s calming to consider how easily their faults might have been yours. (Sure enough, some research has linked disbelief in free will to increased kindness.)

 
Why can’t the world’s greatest minds solve the mystery of consciousness?
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Harris argues that if we fully grasped the case against free will, it would be difficult to hate other people: how can you hate someone you don’t blame for their actions? Yet love would survive largely unscathed, since love is “the condition of our wanting those we love to be happy, and being made happy ourselves by that ethical and emotional connection”, neither of which would be undermined. And countless other positive aspects of life would be similarly untouched. As Strawson puts it, in a world without a belief in free will, “strawberries would still taste just as good”.

Those early-morning moments aside, I personally can’t claim to find the case against free will ultimately persuasive; it’s just at odds with too much else that seems obviously true about life. Yet even if only entertained as a hypothetical possibility, free will scepticism is an antidote to that bleak individualist philosophy which holds that a person’s accomplishments truly belong to them alone – and that you’ve therefore only yourself to blame if you fail. It’s a reminder that accidents of birth might affect the trajectories of our lives far more comprehensively than we realise, dictating not only the socioeconomic position into which we’re born, but also our personalities and experiences as a whole: our talents and our weaknesses, our capacity for joy, and our ability to overcome tendencies toward violence, laziness or despair, and the paths we end up travelling. There is a deep sense of human fellowship in this picture of reality – in the idea that, in our utter exposure to forces beyond our control, we might all be in the same boat, clinging on for our lives, adrift on the storm-tossed ocean of luck. “


Does a chair exist if nobody sits on it? Relational quantum mechanics says ‘NO!’

But you also expect the book has its own independent existence behind those appearances. So when you put the book down on the coffee table and walk into the kitchen, or leave your house to go to work, you expect the book still looks, feels, and smells just as it did when you were holding it.

Expecting objects to have their own independent existence – independent of us, and any other objects – is actually a deep-seated assumption we make about the world. This assumption has its origin in the scientific revolution of the 17th century and is part of what we call the mechanistic worldview. According to this view, the world is like a giant clockwork machine whose parts are governed by set laws of motion.

This view of the world is responsible for much of our scientific advancement since the 17th century. But as Italian physicist Carlo Rovelli argues in his new book Helgoland, quantum theory – the physical theory that describes the universe at the smallest scales – almost certainly shows this worldview to be false. Instead, Rovelli argues we should adopt a “relational” worldview.

What does it mean to be relational?

During the scientific revolution, the English physics pioneer Isaac Newton and his German counterpart Gottfried Leibniz disagreed on the nature of space and time.

Newton claimed space and time acted like a “container” for the contents of the universe. That is, if we could remove the contents of the universe – all the planets, stars, and galaxies – we would be left with empty space and time. This is the “absolute” view of space and time.

Leibniz, on the other hand, claimed that space and time were nothing more than the sum total of distances and durations between all the objects and events of the world. If we removed the contents of the universe, we would remove space and time also. This is the “relational” view of space and time: they are only the spatial and temporal relations between objects and events. The relational view of space and time was a key inspiration for Einstein when he developed general relativity.

Rovelli makes use of this idea to understand quantum mechanics. He claims the objects of quantum theory, such as a photon, electron, or other fundamental particles, are nothing more than the properties they exhibit when interacting with – in relation to – other objects.

These properties of a quantum object are determined through experiments and include things like the object’s position, momentum, and energy. Together they make up an object’s state.

According to Rovelli’s relational interpretation, these properties are all there is to the object: there is no underlying individual substance that “has” the properties.

 

So how does this help us understand quantum theory?

Consider the well-known quantum puzzle of Schrödinger’s cat. We put a cat in a box with some lethal agent (like a vial of poison gas) triggered by a quantum process (like the decay of a radioactive atom), and we close the lid.

The quantum process is a chance event. There is no way to predict it, but we can describe it in a way that tells us the different chances of the atom decaying or not in some period of time. Because the decay will trigger the opening of the vial of poison gas and hence the death of the cat, the cat’s life or death is also a purely chance event.

According to orthodox quantum theory, the cat is neither dead nor alive until we open the box and observe the system. A puzzle remains concerning what it would be like for the cat, exactly, to be neither dead nor alive.

But according to the relational interpretation, the state of any system is always in relation to some other system. So the quantum process in the box might have an indefinite outcome in relation to us, but have a definite outcome for the cat.

So it is perfectly reasonable for the cat to be neither dead nor alive for us, and at the same time to be definitely dead or alive itself. One fact of the matter is real for us, and one fact of the matter is real for the cat. When we open the box, the state of the cat becomes definite for us, but the cat was never in an indefinite state for itself.

In the relational interpretation, there is no global, “God’s eye” view of reality.

What does this tell us about reality?

Rovelli argues that, since our world is ultimately quantum, we should heed these lessons. In particular, objects such as your favorite book may only have their properties in relation to other objects, including you.

Thankfully, that also includes all other objects, such as your coffee table. So when you do go to work, your favorite book continues to appear is it does when you were holding it. Even so, this is a dramatic rethinking of the nature of reality.

On this view, the world is an intricate web of interrelations, such that objects no longer have their own individual existence independent from other objects – like an endless game of quantum mirrors. Moreover, there may well be no independent “metaphysical” substance constituting our reality that underlies this web.

As Rovelli puts it:

We are nothing but images of images. Reality, including ourselves, is nothing but a thin and fragile veil, beyond which … there is nothing.The Conversation

This article by Peter Evans, ARC Discovery Early Career Research Fellow, The University of Queensland is republished from The Conversation under a Creative Commons license. Read the original article.