Posts Tagged ‘philosophy’
Natalie Wolchover reports in Quanta:
Physicists typically think they “need philosophers and historians of science like birds need ornithologists,” the Nobel laureate David Gross told a roomful of philosophers, historians and physicists last week in Munich, Germany, paraphrasing Richard Feynman.
But desperate times call for desperate measures.
Fundamental physics faces a problem, Gross explained — one dire enough to call for outsiders’ perspectives. “I’m not sure that we don’t need each other at this point in time,” he said.
It was the opening session of a three-day workshop, held in a Romanesque-style lecture hall at Ludwig Maximilian University (LMU Munich) one year after George Ellis and Joe Silk, two white-haired physicists now sitting in the front row, called for such a conference in an incendiary opinion piece in Nature. One hundred attendees had descended on a land with a celebrated tradition in both physics and the philosophy of science to wage what Ellis and Silk declared a “battle for the heart and soul of physics.”
The crisis, as Ellis and Silk tell it, is the wildly speculative nature of modern physics theories, which they say reflects a dangerous departure from the scientific method. Many of today’s theorists — chief among them the proponents of string theory and the multiverse hypothesis — appear convinced of their ideas on the grounds that they are beautiful or logically compelling, despite the impossibility of testing them. Ellis and Silk accused these theorists of “moving the goalposts” of science and blurring the line between physics and pseudoscience. “The imprimatur of science should be awarded only to a theory that is testable,” Ellis and Silk wrote, thereby disqualifying most of theleading theories of the past 40 years. “Only then can we defend science from attack.”
They were reacting, in part, to the controversial ideas of Richard Dawid, an Austrian philosopher whose 2013 book String Theory and the Scientific Method identified three kinds of “non-empirical” evidence that Dawid says can help build trust in scientific theories absent empirical data. Dawid, a researcher at LMU Munich, answered Ellis and Silk’s battle cry and assembled far-flung scholars anchoring all sides of the argument for the high-profile event last week.
Gross, a supporter of string theory who won the 2004 Nobel Prize in physics for his work on the force that glues atoms together, kicked off the workshop by asserting that the problem lies not with physicists but with a “fact of nature” — one that we have been approaching inevitably for four centuries.
The dogged pursuit of a fundamental theory governing all forces of nature requires physicists to inspect the universe more and more closely — to examine, for instance, the atoms within matter, the protons and neutrons within those atoms, and the quarks within those protons and neutrons. But this zooming in demands evermore energy, and the difficulty and cost of building new machines increases exponentially relative to the energy requirement, Gross said. “It hasn’t been a problem so much for the last 400 years, where we’ve gone from centimeters to millionths of a millionth of a millionth of a centimeter” — the current resolving power of the Large Hadron Collider (LHC) in Switzerland, he said. “We’ve gone very far, but this energy-squared is killing us.”
As we approach the practical limits of our ability to probe nature’s underlying principles, the minds of theorists have wandered far beyond the tiniest observable distances and highest possible energies. Strong clues indicate that the truly fundamental constituents of the universe lie at a distance scale 10 million billion times smaller than the resolving power of the LHC. This is the domain of nature that string theory, a candidate “theory of everything,” attempts to describe. But it’s a domain that no one has the faintest idea how to access.
The problem also hampers physicists’ quest to understand the universe on a cosmic scale: No telescope will ever manage to peer past our universe’s cosmic horizon and glimpse the other universes posited by the multiverse hypothesis. Yet modern theories of cosmology lead logically to the possibility that our universe is just one of many.
Whether the fault lies with theorists for getting carried away, or with nature, for burying its best secrets, the conclusion is the same: Theory has detached itself from experiment. The objects of theoretical speculation are now too far away, too small, too energetic or too far in the past to reach or rule out with our earthly instruments. So, what is to be done? As Ellis and Silk wrote, “Physicists, philosophers and other scientists should hammer out a new narrative for the scientific method that can deal with the scope of modern physics.”
“The issue in confronting the next step,” said Gross, “is not one of ideology but strategy: What is the most useful way of doing science?”
Over three mild winter days, scholars grappled with the meaning of theory,confirmation and truth; how science works; and whether, in this day and age, philosophy should guide research in physics or the other way around. Over the course of these pressing yet timeless discussions, a degree of consensus took shape. . .
Some very interesting books. I read The Evolution of Cooperation years ago, and it’s a terrific book. I was pleased that the winner of both competitions in the book was a program created by Anatol Rappoport, author of Operational Philosophy, a book that I read in high school and is still quite intriguing. The person interviewed is Vlatko Vedral:
Vlatko Vedral is Professor of Quantum Information Theory at the Universities of Oxford and Singapore. He has published over 100 research papers in quantum mechanics and quantum information and was awarded the Royal Society Wolfson Research Merit Award in 2007. He has held a Professorship at Leeds, visiting professorships in Vienna and Singapore (NUS) and at Perimeter Institute in Canada. He is the author of Decoding Reality: The Universe as Quantum Information.
The interview begins:
Your first book is Quantum Physics: Illusion or Reality? by Alastair Rae.
This is a completely popular book about quantum physics: there is not a single equation in there, I think. What he does is to go through all the major ways in which we try to understand quantum physics, all the major interpretations. It’s extremely good in that he writes in a very objective way and it’s very difficult to tell which one he supports. It’s very passionately argued as well, and it’s a beautiful exposition, very philosophical. I think it’s the best, probably my favourite, popular account of all the things we argue about on the fundamental side of quantum physics.
There are all kinds of strange views on what quantum physics actually is.
Right. There are connections with religion, then there are extremes saying it’s all in the mind: basically that nothing becomes real until we measure it and look at it and consciously record it. On the other side there is a point of view that it’s as real as anything else, out there independently of us and so on. He talks about these two extreme views and what quantum physics tells us about this very old question: whether the world is ideal or real.
Does he resolve it?
He really leaves it open because, to be completely honest about these issues, I don’t think we have something that’s universally accepted as the view: each has lots of positive points but also something that makes it a not completely plausible view to hold. That’s a really nice book.
Your second book?
The Ghost in the Atom. This was actually a sequence of radio interviews recorded by Paul Davies, who’s probably the best populariser of physics we have.
He’s the Search for Extra-Terrestrial Intelligence guy?
Right. He’s written a book about that as well. I think in the 70s/80s he conducted a set of radio interviews with about 10 of the leading physicists of the time. And the spirit is similar to the previous book in that it’s all to do with how we understand the unusual phenomena in quantum physics. The book is written as a dialogue – Davies asks a question and then the interviewee answers – and I would say this format is a much more exciting read than typical prose where someone exposes something. It also goes into personal issues, which you usually don’t get in these books, in that he asks each person about how they got engaged, when did they first learn about quantum mechanics, how did they learn it? It’s really fantastic, an amazing read.
To whom does he speak?
People like John Bell, who came up with Bell’s Inequality, which was one way of quantifying the weirdness in quantum mechanics; then David Bond who has one of those interpretations that tries to retain, I would say, some kind of reality in quantum mechanics, arguing that the world is still as real as it was in a Newtonian kind of framework. Davies chose a person to represent each of these points of view, and it’s really interesting how the interview is conducted and then where it leads – how different people end up in completely different parts of quantum physics, and what they find exciting, and so on.
Does it lead you to believe that maybe people go into quantum physics to prove an idea that they’ve already had?
That’s an interesting point. It’s difficult to tell what comes prior to what, right? In a way we do have these inner feelings, all of us, as to what we think the world should be like. And we usually carry this prejudice with us into our research as well, so it’s not clear whether you come with a prejudice and then you’re trying to use this theory to confirm what you already thought the world was like prior to that. In this kind of interview it’s easy to expose these kinds of things: you can see that people started with some ideas and then maybe changed them or didn’t change them as they did research.
All these unifying theories that quantum mechanics proves, seem to have already been posited in literature or religion or whatever.
Yes, I don’t think there is anything really distinctly novel that was brought there philosophically by quantum mechanics. The key tenet I would say is this randomness that is at the core of our interaction with the world: there is an element that you can never make more deterministic. And, of course, randomness as a way of looking at the world existed for a long time. If you go back to the ancient Greeks I think you will see a spectrum of all of these world views already present there.
Your next book? . . .
I’ve found some new books about process philosophy, and I’m very excited. Truly, process philosophy seems to have a sounder basis in—or approach to—reality than some other approaches. From Process Philosophy: A Survey of Basic Issues, by Nicholas Rescher:
… It seems sensible to understand “process philosophy” as a doctrine committed to, or at any rate inclined toward, certain basic propositions:
- Time and change are among the principal categories of metaphysical understanding.
- Process is a principal category of ontological description.
- Processes are more fundamental, or at any rate not less fundamental, than things for the purposes of ontological theory.
- Several, if not all, of the major elements of the ontological repertoire (God, Nature as a whole, persons, material substances) are best understood in process terms.
- Contingency, emergence, novelty, and creativity are among the fundamental categories of metaphysical understanding.
A process philosopher, then, is someone for whom temporality, activity, and change—of alteration,striving, passage, and novelty-emergence—are the cardinal factors for our understanding of the real. Ultimately, it is a question of priority—of viewing the time-bound aspects of the real as constituting its most characteristic and significant features. For the process philosopher, process has priority over product—both ontologically and epistemically. This process-oriented approach is thus historically too pervasive and systematically too significant to be restricted in its bearing to one particular philosopher [he’s thinking here of Alfred North Whitehead, whose book Process and Reality, was quite influential – LG] and his school. Indeed, one cardinal task for the partisans of process at this particular juncture of philosophical history is to prevent the idea of “process philosophy” from being marginalized by limiting its bearing to the work and influence of any single individual or group.
In addition to the book mentioned, above, I have Process Metaphysics: An Introduction to Process Philosophy, also by Nicholas Rescher (and, I think, a better introduction than the book above, which has a certain focus on unsolved problems and unfinished tasks in process philosophy: suggestions for research and thought, in other words), and Process-Relational Philosophy: An Introduction to Alfred North Whitehead, by C. Robert Mesle. Although one shouldn’t overemphasize Whitehead in a general discussion of process philosophy, he’s nonetheless a major figure in its develop—though in fact, one can trace it back to Heraclitus as the earliest exponent, and certainly Leibniz was a major figure as well.
I have three books by Henri Bergson on order as well—he, too, is a proponent of process philosophy.
I find this fascinating, though others may not.
Worth downloading if philosophy’s your thing. From the link:
These lecture notes have been developed over many years and draw on material presented by Alan Code in his Introduction to Ancient Philosophy course given at UC-Berkeley in the 1980s when I served as his Teaching Assistant. Prof. Code has granted permission for use of the material which is, at this point, integrated throughout the notes.
Here’s one example:
Why Be Moral? — Republic I-II (PDF)
Does your belief in determinism (or free will) making you more or less likely to cheat? Determinists will, of course, say that the question is meaningless: if you cheat, it’s not a matter of choice, since there is no (true) choice, merely the illusion of choice. OTOH, even if determinism is true, you can (or—more properly—are forced to by being pre-determined) measure the difference in cheating rates between those who believe in determinism and those who believe in free will. And someone has done an experiment to find out what happens:
Do we have free will? While some may see the question as trivial, it’s a challenging topic that has been actively debated for centuries. Whether or not you believe a god is involved, a case can be made that free will is simply an illusion, and that every “decision” we make is completely controlled by factors outside of an individual’s control.
Yet others have argued that a belief in free will is essential to morality. If we don’t actually have any control over the decisions we make, how can we be held accountable for them? Several studies have suggested that when kids believe their achievements are due to innate ability rather than their own effort, they are less likely to persist at similar tasks in the future. But until recently, no study has attempted to directly study belief in free will and how it affects behavior.
Kathleen Vohs and Johnathan Schooler have found a way to study this question (though they can’t tell you whether they were predestined to do it or they came up with the idea through their own independent efforts!). They had 30 students read one of two passages by Francis Crick. The first passage argued that most scientists now recognize free will as an artifact of the way the brain works, that free will is simply an illusion and our actions are determined solely by genetics and the environment. The second passage discussed consciousness and did not bring up free will at all. Then the students were given a test to measure their belief in free will versus determinism.
Finally, the students were asked to take a computerized mental arithmetic test with twenty questions like 1 + 8 + 18 – 12 + 19 – 7 + 17 – 2 + 8 – 4 = X. Next came the key to the experiment: the experimenter told them there was a small computer “glitch” that caused the answer to be displayed shortly after the question appeared. To avoid the glitch, students had the space bar as soon as they saw each question. In fact, the computer recorded both the answers and whether or not the space bar was pressed. Here are the results:
What good is it, anyway?
No one doubts that our experience of phenomenal consciousness—the felt redness of fire, the felt sweetness of a peach, the felt pain of a bee sting—arises from the activity of our brains. Yet the problem of explaining how this can be so seems to many theorists to be staggeringly hard. How can the wine of consciousness, the weird, ineffable, immaterial qualia that give such richness to subjective experience, conceivably arise from the water of the brain? As the philosopher Colin McGinn has put it, it’s like trying to explain how you can get “numbers from biscuits, or ethics from rhubarb.” The philosopher Jerry Fodor recently claimed, “The revisions of our concepts and theories that imagining a solution will eventually require are likely to be very deep and very unsettling.”
If you smell theoretical panic, you’re right. But are the scientific answers really so far out of reach? Have people been beguiled by the marvelous properties of consciousness into asking for the moon, while what is at issue is really much more down to earth? Everybody says they are waiting for the Big Idea. But perhaps the big idea should be that consciousness, which is of such significance to us subjectively, is scientifically not such a big deal.
It all depends on asking the right questions at the outset. I can show what I mean with the example of a well-known visual illusion. Consider what you might want to explain about the experience of looking at the object in the picture to the left (Fig. 1), a solid wooden version of the so-called impossible triangle. Since it is at first sight so surprising and impressive, any of us might very well innocently ask the (bad) question: “How can we explain the existence of this triangle as we perceive it?” Only later—indeed only once we have seen the object from a different viewpoint (Fig. 2), and realized that the “triangle as we perceive it” is an illusion—will it occur to us to ask the (good) question: “How can we explain the fact we have been tricked into perceiving it this way?”
Now, no one wants to think that consciousness is likewise some kind of trick. But let’s nonetheless see where the analogy may lead. The standard philosopher’s example is the case of what it’s like to see red. So, suppose you were looking at a ripe tomato: What might you want to explain about the qualia-rich red sensation that you are experiencing?
Since the qualia are indeed so up-front and remarkable, and since no one knows why this is, we are all, most probably, going to start off by asking what may be a bad question: “How can we explain the existence of these qualia as we experience them?” So here, again, it will only be if we undergo a radical shift in perspective and realize that the “qualia as we experience them” could be a mental fantasy, that we shall move on to asking what may be the good question: “How can we explain why we have the impression that such fantastic qualia exist even if they do not?” But, here is why it is likely to be so difficult to make this move: In the case of consciousness, we cannot simply change our perspective to see the solution. We are all stuck with the first-person point of view. So, the result is we persist with questing for the qualia as such.
Yet if consciousness is a trick, then of course this quest is a fool’s errand. It will make no more sense to try to explain the existence of qualia than it would to explain the existence of the impossible triangle. What we should be doing instead is trying to explain just how we have been set up—and why.