Long time readers of this blog will recognize the name Sabine Hossenfelder. I have referred to her and ideas she has championed with some regularity. I am sad to report that attempts have been made to silence Dr Hossenfelder and happy to add that she has resisted them, and appears likely to continue saying what she means for some time to come. Hossenfelder has a doctorate in theoretical physics from Goethe University Frankfurt. Her dissertation, in 2003, looked at microscopic black-hole production. Lately, she has acquired some prominence as a nemesis of what she considers bullshit in the world of science and of physics in particular. She believes that physics as an academic field of research has guided itself into a dead end, where bullshit creation is incentivized. Recently, for example, a distinguished scientific journal published a paper about the mathematical modeling of 'warp drive' as a way to get near and/or past the speed of light. The paper was then pic...
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Eric Weinstein is. by occupation, a VC fund manager. He is also an economist. In 2002 he co--authored a paper (with Adil Abdulali) on the valuation perversities of mortgage-backed securities. That paper looks pretty good in retrospect, after those perversities helped feed in to the crises of 2007-08. By education, he is a mathematician, having received a Ph.D. in the field from Harvard for a thesis on the extension of self-dual Yang-Mills equations. No, I don't know what that means. I do know something about VC managers and about mortgage backed securities, though, and it's my blog, so I will proceed. In aspiration anyway, Weinstein is a also a physicist. He has devised what he calls a theory of "Geometric Unity" which he believes may reconcile quantum theory with Einsteinian relativity. He theory bubbled along in obscurity for some time until somehow it drew attention from television host Piers Morgan. Piers Morgan had Weinstein on his show, coupled with Sean Ca...
I admire those scientists -- I mean actual credentialed working scientists -- who deign to spend a lot of time explaining science to layfolks like me. They are a differentiated bunch. Examples that come to mind are: Neil deGrasse Tyson, Lawrence Krauss, Michael Polanyi, and -- my personal favorite -- Sabine Hossenfelder. This must be roughly the tenth time she has inspired a post in this humble blog. Let me introduce her credentials. Hossenfelder has a Ph.D. from Goethe University Frankfurt, for which she wrote a thesis on "Black Hole Relics in Large Extra Dimensions." That will give a flavor of such of her work as is aimed at peers. She is also a fellow blogger. In a recent post on one of those blogs she argues that humans have been lying to ourselves about plastic. She thinks that the stuff is building up and may well prove disastrous for us. To this point she cites the OECD, which says that the use of plastics doubled globally in the period 2000 to 2019...
The relationship is complicated. Let us take four points. First. both were path-breaking mathematicians. Descartes’ invention of analytic geometry made possible, a generation later, Newton’s (and Leibniz') development of calculus. Second, they had very different ideas about matter and how different chunks of matter interact. Descartes wanted to get rid of the idea of “occult” causes and effects, or what some call teleology. To speak very roughly, mechanistic explanations involve pushing and teleological ones involve pulling. For Descartes, everything that happens in the material world had to be explained by things pushing each other around. There could be no “action at a distance,” no pull, just as things didn't happen because inanimate objects (or non-human animals!) wanted them to happen. So the Cartesians of the following generation argued against Newton’s law of gravity — in their eyes Newton was trying to bring back those occult causes, pulling at each other across vast d...
The very existence of neutrinos is something that admirers of The Big Bang Theory (the television show, not the actual theory) might think of in terms of a conversation between Leonard and Sheldon. The theoretical physicists (Sheldon Cooper's real-world colleagues) have been saying they exist for a long time now. Since a paper in 1930 by Wolfgang Pauli. But the experimentalists (Leonard Hofstadter's tribe) have never been able to find one of the little buggers. Now, it seems they have. Leonard has reported this and Sheldon has said "I told you so." Heck, the Japanese built a huge facility specifically devoted to the detection of neutrinos, called the Super Kamiokande. In essence, it is a big tank of water with a lot of photomultiplier tubes in it. The tubes allow the physicists to watch for the predicted "Cherenkov radiation." Whatever that is supposed to be. It didn't help. Now, the credit for the key experimental observation goes to the Large Hadr...
Nanotechnology is engineering on a very small scale: atom by atom. One critical consideration in nanotech is that it works at a scale quantum mechanical effects are important. I love this stuff. I am of the opinion that contemporary science is much too devoted to distinctions among layers of reality defined by scale. So ... physics deals with atoms, chemistry with molecules, biology with organisms. Each presumes its own set of laws and generally ignores rthe laws of the level below it, aside from general hand-waving acknowledgements when diplomatic. Yet the walls among the disciplines are falling down. That is a subject for other days, it simply explains why I find nanotechnology -- not so much science as a branch of engineering, operating on the border between physics and chemistry. Only days ago a team of researchers from two great universities, the University of Toronto on the one hand and Rice University on the other, reported the first measurements of the ul...
Here is a link to a good review of what seems to be an important book about the current state of physics. Review: Lost in Math by Sabine Hossenfelder (eyrie.org) The author of the book, Prof. Hossenfelder, has a blog I'm sure I've quoted from a time or two here. She is plainly no admirer of string theory or of a "many-worlds" interpretation of quantum mechanics, I will say no more. Except that I like the illustration google images offered me for the many-worlds theory you see here. Man and woman meet. They are either a love connection or not (the lid is opened and that cat is alive or dead). The time lines split. In the bottom half, we see the world if they part quickly. Either our protagonist meets another woman or he lives alone, The world splits again. And so forth. Cute and simply done.
Recently, the physicist Sabine Hossenfelder, who maintains a wonderful blog, posted her thoughts about "infinity," its necessity as a mathematicians' tool, on the one hand, but its unreality from the point of view of the science of physics, on the other. Her point is that a physicist only regards something as real if it is necessary in order to explain an observation. Infinity, she says, will never fill that bill. She also went a bit into the mathematics of infinity, and the fact that not all infinities are the same. The real numbers are a different sort of infinity from the integers. I used the co mment section under her blog post to ask a question that has long been on my mind. I remember when I was a kid, many decades ago, some of us nerdy types excitedly read "One, Two, Three, Infinity" by George Gamow. Gamow covered some of the same territory you just did although I'm guessing progress has been made in the last half century or so. If I recall corr...
My view of Spencer as a philosopher has largely been shaped by William James' comments on Spencer,which were consistently negative. This negativity was later confirmed as I came to understand the criticisms of Spencer offered by G.E. Moore and Emile Durkheim. Nonetheless, Murray Rothbard has said good things about Spencer, and there has been a bit of a Spencer revival in recent years, The online Stanford Encyclopedia of Philosophy says that Spencer has been the victim of "interpretive caricatures," and that it is fortunate he is enjoying some "restoring and repairing" scholarship. So: I decided to go back to the source. In Spencer' FIRST PRINCIPLES (1862), he wrote as follows about economic markets: The production and distribution of a commodity imply a certain aggregate of forces causing special kinds and amounts of motion. The price of this commodity is the measure of a certain other aggregate of forces expended in other kinds and amounts of motion by ...
A fine review. Is it rational for me to feel a sense of loss at the fact that the NDPR has said au revoir? https://ndpr.nd.edu/news/nothing-tome-a-defence-of-the-growing-block-theory-of-time/ I believe I've described it before. The "growing block" theory of reality, also a theory of time, is that which postulates that the present and past are real. The future is not yet real. So reality is growing, and the present moment is the edge of its growth. This is an attractive theory in that it sets out how the world seems to work. We should not depart from such a persistent seeming without reason. I wake up in the morning and find that a variety of changes that I made to my apartment are still here. The book shelf I put up yesterday is still here. Unless I'm a bad carpenter and it fell overnight. In which case there is a mess of books and wood on the floor. Even in that case, though, reality has grown by the addition of a new shelf, and then by the further addition of ...
I am told that physicists, astronomers, and cosmologists dream about is the placement of a radio telescope on the far side of the moon. Putting it on the dark side would of course ensure that the planet earth would not be in its way. What is more important, the moon has no atmosphere, so the clarity of radio 'view' the human race would get of distant parts of the cosmos would be ... well, to use a technical phrase, an ass-kicking thrill. And though a radio telescope would be all that, ambitious scientists have additional related ideas. For example, there is a proposal to put a gravitational wave interferometer in the moon. Obvious question ... a whaaaaat? Interferometry is a set of techniques by which waves are made to interfere with one another, creating patterns that convey information. Usually this sort of measurement involves electromagnetic waves. But the study of gravitational waves is a new thing. The first direct observation of gravity waves was recorded in...
The idea of inertia is not new. It was not invented by Newton, or even by Galileo. Galileo did make a fascinating elaboration on it, though. Let's look at the famous thought experiment in which he talked about dropping balls of different sizes from the Tower of Pisa. The point of the experiment is that, although there are in principle two ways of measuring mass, they come out to be the same. One can measure mass by inertia, or one can measure it in terms of gravity. If mass (gravity) is the important variable in our thought experiment, then one would expect the heavier ball -- say a cannon ball -- to fall to the ground more quickly than the small one, say, the pebble. On the other hand, if mass (inertia) in the important variable than one would expect the cannonball to move more slowly than the pebble. Inertial mass holds it back from the free fall the pebble enjoys. The only way that the cannonball and the pebble fall at the same ...
I don't know whether there is a "hierarchy problem" in contemporary subatomic physics or not. There seems to be some debate over whether the hierarchy issue is a problem. Let us call it the meta-hierarchy problem. The idea, though, is that the Higgs boson is very very small. Too small, some think, to be expected to do the job that theory assigns to it, that is, to explain why particles have mass. The point? Physicists believe that there should be some intermediary structuring, stuff larger than the Higgs boson, but smaller than Planck's constant. Is this really a problem, then? Depend on to whom you listen. Some believe they are only pretending there is a problem so as to get the money for another supercollider, which they are pitching as the way to fill in the hierarchical blanks.
It has been more than five years since I posted here about the "twin paradox," an issue raised by relativity physics. I'll link you to that discussion: http://jamesian58.blogspot.com/2012/09/the-twin-paradox.html If you follow that URL, you will find that I have only in recent days received my first comment on that post. I find this in itself fascinating. It speaks to the whole internet-postings-are-forever thing. Once you put something out, you never know when somebody who might comment interestingly about the subject will happen across it. Anyway, my correspondent gives no name for himself beyond "The Physics Guy." He is apparently using my humble observations to plug his own new blog, Physics Talk. The first three entries of "Physics Talk" are now up, and the third of them (posted December 30, 2018) deals with the twins. I'm not overly impressed. His discussion of this paradox doesn't say anything my own discussion in 2013 didn...
The question for the day, how closely related are these two contentions, by MP: 1. "While tacit knowledge can be possessed by itself, explicit knowledge must rely on being tacitly understood and applied. Hence all knowledge is either tacit or rooted in tacit knowledge. A wholly explicit knowledge is unthinkable." 2. "The information in DNA could no more be reduced to the chemical than could the ideas in a book be reduced to ink and paper: something beyond physics and chemistry encoded DNA."
There are surely respects in which the notion of “space-time” as a unitary block, the view of time as just one of its dimensions, has served a useful role in the further development of science and technology. Insofar as it does, we might accept it pragmatically as true. But (secondly) broad propositions are often ambiguous, even when not obviously so, and in the case of any ambiguity it is always open to us to say that the statement or the idea is true in one respect, false in another. What might tempt us even at an early blush to suspect that there are respects in which this idea is false? There are the various ambiguities and paradoxes that come with the idea. Consider the bicycle in the doorway as an example. A bicycle stands in an open doorway such that the front of the bike is inside the house, the back of the door is outside. A philosopher asks us, “Well, is the bike in the house or not?” We might well reply, “some parts are, some parts are not.” Simp...
Most of us have a sense that there is something about us that is peculiarly private, known only to us, and that the contents of what we call our "mind" are almost (?) definitionally this peculiarly private stuff. This is why "mind reading" is such a popular magic trick. To have someone pull a rabbit out of a hat is one thing, and all good fun. But to pull out my thoughts from my head? "Think of any number between one and ten ... you are thinking of four!" -- THAT sort of trick is slightly threatening, though in the context of a stage show the threat is of course contained so the audience doesn't flee in horror. In history-of-philosophy terms Descartes certainly helped codify our sense of ourselves as a tight fortress with a private theatre inside, it is the "I" which "thinks" and which holds itself as its first certitude. As a consequence and one might say as a mitigation of this sense of privacy, we talk of putting ourselv...
I have now and then wondered, as my mind wandered, whether there can properly be said to be such a creature as the "philosophy of chemistry." Biology has philosophical controversies specific to itself: the explication of the concept of natural selection for example, or the age-old reductionism-versus-holism thing. Physics, likewise, has its own philosophical controversies. Indeed, much that goes by the name "philosophy of science" seems actually to be a philosophy of physics.The nature of space and time. Statistical mechanics, etc. But chemistry? Wouldn't any effort to assign specific philosophical controversies to chemistry inevitably veer in one or the other of those directions? So I mused. Bu t it appears there really is a "philosophy of chemistry." Philosophers working this field debate whether chemistry is the study of substances or reactions -- stuff or events. In the words of Joachim Schummer, " Substance philosophers define a che...
A recent essay by th e philosopher Galen Strawson has looked at the mind-body problem from a distinctive angle. The title of the essay seems more straightforward than it is. "Consciousness isn't a mystery. It's Matter." One first gets the impression that Strawson is taking a straightforward materialist/eliminativist view: consciousness simply is matter in one of its operations. But that is to presume that the "it" in the second sentence is an unambiguous reference to the word "consciousness" in the first sentence. Another reading suggests itself, though. The "it" could refer to the word "mystery." The second sentence would then mean, "It's matter that is the real mystery." Both meanings fall within the scope of Strawson's intention. It is what Strawson calls a Very Large Mistake to think that we know enough about matter, through the science of physics, to know that consciousness can't be a materi...