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Stephen Hawking and Philosophy
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Stephen Hawking and Philosophy |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
I thought this was interesting: http://www.prospect-magazine.co.uk/ArticleView.asp?Accessible=yes&P_Article=7269 From the text: "Current theories of astrophysics, with tales of the big bang, black holes and antimatter, have the feel of science fiction. And in a sense that is what they are: the stories of contemporary science. These stories are not unconstrained; they do not allow anything to be said. For the stories of science have an internal logic which drives them forward. They are often useful. We live by our closures. But we should not imagine that we have thereby captured the secrets of the universe. Nor should we suppose that there are not countless alternatives, offering other ways of holding the world that may be equally valid." I'm not quite sure how to read this. My problem is with 'equally valid'. Yes, I suppose there're countless other alternatives but I don't quite understand what 'equally valid' means. I agree that we shouldn't privilege physics as the true description, but if you want to overturn it, you have to find a description that is more useful than physics for the same goals or you have to change the goals were pursuing. What's equal about that? Brad [This message has been edited by Brad (edited 12-04-2001).] |
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Alicat Member Elite
since 1999-05-23
Posts 4094Coastal Texas |
Equally valid views of astrological concepts for this world are nigh on impossible, since we as a species have vastly different conclusions about what the world actually is, creating justifications and rationales to support that conclusion. The best that can be hoped for is an agreement to disagree. The sciences exist off of empirical data, feeding on mathematical 'certanties' to validate existence. For example, though no-one has seen a worm hole or black hole, they can be proven mathematically. But I'm cynical in that respect...anything can be proven, with the exception of the Unification Theory, by manipulating the data until the 'right' answer is achieved. Also, I can't help but feel that many theorists put the cart before the horse: making conclusions then working out the questions to support and prove those conclusions. |
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Local Rebel Member Ascendant
since 1999-12-21
Posts 5767Southern Abstentia |
I'll have to preface my comments by saying that even though I LIKE this topic, Hawkings, and theoretical physics in general -- for us to have this conversation is a tad like a few blokes sitting around the docks discussing Christopher Columbus' theories about a round world without the benefit of ever having even sailed ourselves. At the same time, even though Chris could use empirical data to conclude the Earth was round -- he had no idea the scope, and while he could use the stars to navigate -- he had no idea what they were. So, as Ali suggests re: unification theory and the points at which physics reaches it's limits -- we're still speculating on an awful lot -- albeit eductated conjecture tis still conjecture -- therefore one conjecture (that fits in the jigsaw puzzle) is as good as another conjecture (that fits in the jigsaw puzzle). On the other hand -- there's no point in trying to argue that we can't navigate by the stars simply because we don't know what they are. |
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Ron
Administrator
Member Rara Avis
since 1999-05-19
Posts 8669Michigan, US |
I agree. "Equally valid" is, at best, a nebulous phrase. Equally useful might be a little better, but only a little. Trouble is, while I might quibble with the terminology, I certainly can understand the underlying meaning. Newtonian physics, for example, has been "overturned" twice in the last 100 years, first by Relativity and then by Quantum Mechanics. But it's not "wrong" (just incomplete), and for most of us it's more than just useful. It's "how we think," and most of our modern world is based on it. Only when we deal with the very big or the very small, do we need more. Newton's Classic physics, relativity, and quantum theory are very, very different ways of looking at our world. None are wrong, and each is valid within its own domain. Still, these three models aren't contradictory, just different. Let's look at another example. About 2,400 years ago, Euclid stated five postulates upon which all of geometry would be based. 1. We can draw a straight line from any point to any other. 2. We can produce a finite straight line continuously in a straight line. 3. We can describe a circle with any center and distance. 4. All right angles are equal to each other. 5. If a straight line falling on two straight lines make the interior angles on the same side less than two right angles, if produced indefinitely, will meet on that side on which are the angles less than the two right angles. The first four postulates are seemingly "self evident," but the fifth has caused a lot of discomfort. Even Euclid didn't like it much, and he proved his first 28 propositions without using it. But use it he did, because without it, Geometry is incomplete and largely useless. For over a thousand years, mathematicians tried to prove the fifth postulate using only the first four. But without success. In 1813, Gauss, who was arguably the greatest mathematical mind of all time, called it the "shameful part of mathematics." There are many different ways to state the fifth postulate, but it really boils down to parallel lines. Take two parallel lines and extend them forever - will they ever, at some point, meet? According to the fifth postulate, no. One way to prove something mathematically is to try proving the obverse and then look for internal contradictions. If the fifth postulate was reversed, if we assumed that two parallel lines would eventually meet, would all of the propositions and theorems based on those postulates fall apart? Turns out that such a non-Euclidean geometry is entirely, completely consistent. There are no contradictions, and Einstein's General Theory depends on the curved space it predicts. We're not just talking about different views, we're talking about opposing views. Which geometry is valid? Both, I think, are useful. There are, I think, countless examples of alternatives that are equally useful. Is light a wave or a particle? Are the three primary colors red, blue, and yellow, as we all learned in grammar school? Or are they red, blue, and green, as any computer artist will quickly tell you? Is gravity the result of tiny particles called gravitons? Or is it an illusion of curved space, where we're all just "sliding" towards the center of the Earth? As Ali said, science is a reflection of empirical data. But what we've discovered, especially in the past 100 years, is that what we "sense" as empirical is sorely limited. Relativity and Quantum Mechanics are non-intuitive (and often counter-intuitive) simply because our senses are limited. We don't always "see" the world as it really exists. In every single instance, our understanding of the Universe has advanced only when instruments extended our senses. Our senses are impacted by the world we study, and often the world is in turn impacted by our senses. It's not at all surprising to discover that what we see looking left isn't always the same as what we see when we look to the right. Metaphorically speaking, of course.  Ali, I know it sometimes seems as if mathematics can prove anything it wants, but that's really not the case. (Maybe you're thinking of statistics? )You can't follow the rules and still prove that you can trisect an arc, that matter can exceed the speed of light, or that two plus two equals ten. I don't think there is a human endeavor more conservative or more closely scrutinized than mathematics. When you talk about "manipulating data" to get the "right" answer, you're really talking about observational science, which has very little to do with mathematics. Indeed, the whole point of math is to divorce the numbers from the world, to move from the general to abstract. It's the classic difference between the hard and soft sciences, the former based on math and the latter based on observations (and no science is wholly either hard or soft). Hey, I thought y'all knew better than to get me started on science? |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
Ron, Actually, that's what I had hoped for. I knew that both you and LR were interested in this subject (Hawking and the rest), and I thought it was a nice convergence with some of the philosophical ideas I've been playing around with for the last few years. My problem is that I don't think it uses those philosophical ideas accurately. I think it privileges a certain view of the world -- the world the way it really is -- and proceeds to attack Hawking from that point of view. Some of the terminology is Pragmatist but the approach, at least as I read it, is Realist and Hawking has the wrong idea about the Real so to speak. In this sense, it falls into the same trap that Hawking does. Stop worrying about what's really Real and start worrying about what to do about it. There's no philosophical point, at least I can't see one, that bars a unified theory of physics. Especially, of course, if physics follows it's own internal logic. The mystery, then of course, isn't that we can't have one but that we don't have one already. Brad |
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Ron
Administrator
Member Rara Avis
since 1999-05-19
Posts 8669Michigan, US |
I need to apologize, not just once, but twice. First, my earlier post was based solely on the passage you excerpted, Brad, and not on the whole article. Second, LR apparently posted while I was composing my own response, and I never saw it until just now. To be honest, I really didn't take Lawson's article very seriously. If someone is going to argue either for or against a topic, I expect them to do their homework. They don't have to be experts, and it's perfectly fine to admit when they don't understand something, but I won't accept blatant ignorance. Maybe Hilary Lawson's conclusions have merit, but it's hard to justify spending much time with those conclusions when her supporting premises include errors anyone in a ninth grade science class would find laughable. She doesn't understand Newton. How can she even hope to critique Hawking? LR, I don't think Columbus' contemporaries needed to be sailors to explore the nature of a round Earth. At least I hope not, because I ain't flying into a black hole or setting up camp on the head of a neutrino. I doubt Hawking was considering the idea, either. And as it fortuitously turned out, every single clue needed to deduce the shape of our planet was available dock-side. With some careful measurements and very simple math, Columbus could have even made a pretty solid guess about scope. Proving those deductions, of course, was another matter entirely. As to unification theories, one shouldn't confuse them with Grand Unification. We already have unification theories, a whole bunch of them, in fact, dating back to the 1940's. It's just that none of them can adequately account for all four "forces" at the same time. The electromagnetic force, the strong-nuclear force, and the weak-nuclear force have, in various theories, been demonstrated to be the same force (at VERY high energies). The fourth force, gravity, has been a real problem, though. Personally (and this is very much just personal opinion), I don't believe gravity will ever be shown equivalent to the other forces. We've spent nearly a hundred years, since Einstein's General Theory, trying to pigeon-hole gravity into the same cubicle with the other forces and I think the only reason for that effort is that, well, it would be really cool. Reducing our whole Universe to one simple (sic) equation would be what scientists and mathematicians called "elegant." I think this is an example of what Ali called putting the cart before the horse, or reaching conclusions and then working backwards to support them. It's what we want, but that doesn't mean it's what we're going to get. Gravity is something very special in the Universe. It is the weakest of the four forces, and at the same time, the strongest. If there is a particle involved in the interaction of mass, as there certainly is with the other forces, we have yet to be able to detect it. And we've tried. Boy, have we tried! I am convinced (and again, just personal opinion) that gravity is fundamentally different from the other "at a distance" forces and will never be a part of a Grand Unified Theory. Just as a BTW, I always chuckle when Star Trek, Star Wars, ad infinitum, include anti-gravity devices as part of every-day life. If such a thing existed it would be equivalent to a perpetual motion machine and the source of infinite energy. |
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Local Rebel Member Ascendant
since 1999-12-21
Posts 5767Southern Abstentia |
Ron, No need to apologize on my part... I wasn't slighted by your post. As to be expected you presented cogent observations on the subject. I think Lawson does have an interesting point albeit the arguments are flawed -- re: our views of the limitations of church in current paradigms comapared to future understanding of science... but I don't think that means wholesale what Lawson presented either... I think rather (as you've even hinted) that our posterity will view our understandings much the same as we hold alchemists attempting to turn iron into gold. |
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Local Rebel Member Ascendant
since 1999-12-21
Posts 5767Southern Abstentia |
Oh.. almost forgot... My reference to Columbus was not meant to say we have to go to a black hole... but... if I could get close to one I might.. Rather it was to say that (at least speaking for myself) I don't have the equipment of Hawkings, Einstien, or Heisenberg....or even our old friend Newton for that matter. In fact I've always thought of myself as a somewhat retarded (or mentally challenged) genius, since on any given day depending on what I had for breakfast, the phase of the moon, how much sleep I've had, the test itself, and or the administrator thereof -- my IQ ranges anywhere from 135 to 155 -- I just don't have the capicity of the great navigators of physics -- but it is fun and interesting to talk about. |
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Midnitesun
since 2001-05-18
Posts 28647Gaia |
LOL, as only the force of gravity keeps me in my chair sometimes while I read at this site. In 1873 Jules Verne published Around the World in 80 Days. I'm sure there was considerable laughter from the general populace at such a preposterous idea, just as there must have been 'gales' of laughter at the ignorance that propelled Columbus forward to the bravest New World. And yet, here we are, capable of traveling "Around the world in under 8 seconds", via the net. What next? I love both Science and Sci-fi, but MATH?????? Not this chair hugger. You leave me in cosmic dust with math, and I'm having difficulty and nightmares homeschooling my teenager in basic Algebra. Now that is scarier than anything in the Universe. Just a little levity thrown into this subject. Forgive me. |
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Brad Member Ascendant
since 1999-08-20
Posts 5705Jejudo, South Korea |
midnitesun, Did you read the article? There's no math in it. LR, I suppose you're right but the way it is written, it just seems to trade one ontological privileging (physics) for another (openness). How do you prove the universe is open? How do you know that your proof is true? Ron, If you have time, could you elaborate more on gravity. Do you have a different approach beyond "I make no hypotheses." Ali, Where'd ya go? Brad |
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Alicat Member Elite
since 1999-05-23
Posts 4094Coastal Texas |
Still here Brad. Been reading and re-reading this thread and thinking. That might explain my slight headache, since it only hurts the first time.  What I've been thinking deals with scientific fact and fallacy, and things about gravity. I might need more education on gravity, but am I right in ascertaining that the higher you are the less gravity affects you, just like the lower you are the more? How does that equate to pounds pressure and cubic feet? Or does that dwell more on relational pressures and specific densities? I know that while in water, the body is bouyant (to a degree) and lighter (or the perception of). I know this is due to lung capacity of air, amid other factors. I also know that the deeper underwater one goes, the more pressure is exerted on the lungs, or any artificial atmosphere. I gotta wonder about things sunk in the Mariana Trench (roughly 5 miles deep, courtesy of Encarta.com), since those pressures would be great enough to crush steel plates. So would that mean that gravity is a constant, incrementally increasing as one nears the Earth's core? Or is it a variable force, dependant solely upon altitude? Or am I thinking of atmospheric pressure verses gravitational forces? Also mingled with gravity in my head were some fallacies of scientific thought based upon observational data. Flat Earth, Hollow Earth, and Geocentric Earth are a few. Phrenology was a 'science', but didn't withstand close scrutiny. But I also know that mere accumulation of observational data does not create fact. Just me being persnikitty again. Alicat |
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Ron
Administrator
Member Rara Avis
since 1999-05-19
Posts 8669Michigan, US |
Brad, I don't think there has ever been a time when I pulled a "I make no hypotheses" on anyone. It's that "if you have time" that's usually a problem for me. Ali, both atmospheric and water pressure are definitely related to gravity. We have a few miles worth of air on top of us, and that's only a little different than having a baby grand piano sitting on top of us. In an open system, pressure is just another word for weight. Of course, that "only a little" difference feels like a pretty big difference if you happen to be the one stuck under that baby grand. The difference is that air and water "flow" and we feel their "weight" from many different directions. Okay, it's a pretty big difference, I guess. Because we would, otherwise, be crushed. A ten by ten inch square of paper has about 1,450 pounds of air sitting on top it. Ouch. But because air "flows," it also has 1,450 pounds of air pushing in the other direction. It works exactly the same way with water, except the weights are even more staggering. At the bottom of the Mariana Trench the pressure is over 8 tons per square inch. That same piece of paper would now have 8,000,000 TONS sitting on it. However, a steel girder at the bottom of Mariana Trench would NOT be crushed by that weight, any more than the rocks down there are. The water - and the water pressure - flow all around the girder and everything is cool. A closed box made out of similar girders would be instantly crushed, though, because the water couldn't "flow" inside it to counteract the pressures on the outside (well, it can and it would - explosively so). (Related Aside: Boyoncy in water has very little to do with lung capacity. Put two quarts of air in a steel can weighing 150 pounds, or four quarts of air, and the can is still going to sink. I had a friend in high school who could sit on the bottom of the pool for two minutes. He didn't float. The reason he didn't float was that he remarkably lean, and muscle has a higher density than water. Fat, on the other hand, floats. )You are essentially right about the effects of gravity when you say the higher you are the less gravity affects you. Interestingly, though, it's not quite that simple. Gravity, of course, is described as nothing more than the attraction between two objects and depends only on the mass of the objects and their distance from each other. Note, it's a two-way attraction. Yes, the gravity of Earth is attracting us, pulling us towards the center of the Earth. But we're attracting the Earth, too. It's just so small as to be immeasurable. That's because the strength of the attraction is directly proportional to the amount of mass. For example, we "weigh" less on the moon than we do on the Earth just because the moon has less mass than the Earth. Here's something cool. Spherically symmetric objects (planets, stars, moons, etc.) behave as if all of their mass is concentrated at their centers. Black holes are often called singularities, because all their mass has collapsed to a single point. In a sense, all the planets and stars are singularities, not because their mass has collapsed, but because the entire force of their gravity is concentrated in a single, dimensionless point. The strength of the attraction between two objects depends on mass and, as you surmised, Ali, on distance. It's called the Inverse Square Law and simply means that gravity decreases in proportion to the square of the distance. Right now, you're on the surface of Earth, roughly 8,000 miles from its epicenter. Let's say you weigh 200 pounds. If you move another 8,000 miles from the epicenter, you are twice as far away. But you don't weigh half as much. Gravity is determined by the square, two squared is four, so you weigh one fourth as much, or just 50 pounds. Go another 8,000 miles. You're now three times as far from the epicenter, three squared equals nine, so you weigh one ninth as much, or about 22 pounds. The Inverse Square Law means the strength of gravity drops off VERY quickly as the distance increases. But it never quite drops off to zero. The gravity from our insignificant planet has an affect, however tenuous and immeasurable, on every star in every galaxy. Everything in the Universe really is connected to everything else. Weightlessness? There is no such thing. What we see as weightlessness when the space shuttle orbits the Earth is a very carefully calculated flight path. If the Earth's gravity didn't extend farther than the shuttle orbit, after all, the moon would have been whipped into space a long time ago. What really happens is the speed and centrifugal force of the orbiting shuttle exactly cancel out the gravity, giving an illusion of being weightless. And that raises what I think is one of the most interesting things about gravity. If you were in a closed box and suddenly felt yourself "pulled" toward the floor of the box, there is no way to know whether that "force" is the result of gravity or acceleration. We all know what it feels like when a fast elevator starts moving? It's the same feeling you'd experience if the mass of the Earth suddenly increased. Gravity and acceleration are indistinguishable. In a way, it makes sense. If you jump out of a plane at 5,000 feet, it is gravity that propels you towards the ground. Faster and faster. Falling is nothing more than accelerating, albeit in a usually undesired direction. Gravity is considered one of the four fundamental forces I mentioned in my last post, along with the electromagnetic force, the strong-nuclear force, and the weak-nuclear force. The concept of "force" and much of modern physics goes back all the way to Aristotle. He invented an invisible and frictionless medium called "ether" to explain how things like gravity and magnetism could apparently cause "action at a distance." We finally gave up the idea of ether (somewhere around 1881, I think, when Michelson and Morrley were measuring the speed of light and setting Einstein up to answer the questions they unearthed), but science is still very much determined that cause and effect cannot occur across distance. That is, in fact, a fundamental premise of modern science. The actions at a distance are, today, believed to be caused by particles. We have photons and electrons, for example, to describe the electromagnetic force, and hadrons account for the strong nuclear force. Those I've mentioned have been detected and the theories are hard to debate. The graviton, however, which is the particle that accounts for gravity's ability to act at a distance, has never been detected. In some ways, that's not surprising, just because it's by far the weakest of the four forces. The strong-nuclear force (holds together the nucleus of atoms) is one hundred times stronger than the electromagnetic force, one million times stronger than the weak force, and 10 to the 38th power stronger than gravity. Gravity is a major weenie, and that makes it hard to find the theorized particle. (Gravity is only strong, by far the strongest of the four forces, in the sense of accumulation. All the other forces are limited by their own characteristics. The weak force works only at distances smaller than the size of an atom, and the positive/negative features of the electromagnetic force tend to cancel each other out. Gravity seems to have no such limitations. You want more gravity, you just add more mass.) In theory, everything emits gravitons. When the gravitons meet, they interact to create the "attraction" we experience, not unlike the way we know electrons create the attraction and repulsion we see in magnetism. The trouble is, electrons are very easy to detect and prove. Electrons are strong. Gravitons are so incredibly much weaker that we still haven't been able to find one. As I said before, I personally don't think we ever will. I think we've incorrectly grouped gravity with the other three forces, putting it there simply because it appears to work "at a distance" in the same way the others do. But what if gravity is actually more fundamental than the fundamental forces? I don't have any real answers, of course, just a gut feeling based on things I've read. But gravity and motion seem to have much more in common with each other than gravity does with any of the other forces. No, I'm not suggesting an integral connection. Motion, rather, is an aspect of space. I think we're going to find that gravity, rather than being grouped with the forces, will eventually find itself on par with time and space, the true fundamentals. I suspect it will be the link between what we call space and what we call matter/energy. Thus go the ramblings of true amateur. |
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Alicat Member Elite
since 1999-05-23
Posts 4094Coastal Texas |
And mighty those ramblings are!  Through talking with my friend Pat after my reply, I came to many, but not all, of your conclusions. I just don't have the vocabulary...yet. I do thank you for the clarifications. |
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Local Rebel Member Ascendant
since 1999-12-21
Posts 5767Southern Abstentia |
It's interesting that with the inception of this thread comes the news from the CERN particle accelerator in Geneva that the 'God Particle' or the Higgs Boson has eluded discovery again... Higgs theorized in the 60's there was a particle that accounted for the mass of particles since some have mass and others don't... it all looks good on paper... but it wasn't found at the energy levels as expected. Physisists now wonder if it can ever be found or if the mass of matter can ever be explained... Whatever will be will be... |
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