Thats a pretty good example. I read that as a logical “composition argument” in the sense that the whole is not the same as the sum of the parts; the theory can be globally wrong even though parts of it may work, and the similarity to GR vs Newton is apparent.

This is a fun topic for me, but I don’t want to continue belaboring my points ad-infinitum. Thanks for a thought-provoking back-and-forth on this.

You make good points, but let me ask you this: consider the accelerating rate of the expansion of the universe. If you make a hubble diagram of type 1a supernovae, it’s only out at relatively high redshift that the acceleration becomes detectable. Hence the Nobel Prize this year. By your argument, we should not say that the constant rate of expansion model has been disproven, because it still matches the available data at small redshift. Is that right?

And as far as time delays between mountains and sea level, you should check out http://leapsecond.com/great2005/

Yours,

Don

Good points, all.

This is where I’m coming from: in the historic progression from the Ptolemaic solar system to Copernicus to Kepler to Newton’s Universal Gravity, I argue we can now rule out, disprove, or falsify the various geocentric models with parallax and doppler shift measurements showing the annual periodic motion of the Earth w.r.t. background stars. We can rule out Copernicus’ circular (plus a few epicycle) model on the bases of poor numeric performance. However, Kepler hit the jackpot. To this day, most ephemeris software still use his laws for detailed calculations, I think. Newton’s ideas superseded Kepler because they provide a fundamentally deeper understanding to answer the various questions unanswered by Kepler’s purely phenomenological ideas. In addition to that, Newtons UG predicted a host of other phenomenal not previously addressed (hyperbolic and parabolic orbits, center of mass at foci, etc). However, I argue that Newton did not actually disprove Kepler. In fact, part of his argument was to show that UG yielded Keplers’ laws. To justify, in part, his theory, he had to demonstrate that it actually supported the previous model! Thats hardly disproving it.

I was taught special relativity in a similar vein, that for small v/c, one gets back all the Newtonian and Galilean behavior, thus demonstrating that SR was supported by a few centuries of observational confirmations of Newton. Its hard for me to reconcile that kind of support as ‘disproof’. To be sure, Einstein himself played up the differences (of course, that was the whole point) as you do in the comments, but I think its not wrong to think of the new theory as adding refinements, “corrections” or perturbations as #81 pointed out (of course, the value of the new theory is to add whole new way of thinking, and most importantly, to give more predictions and more universal understandings).

At the end of the day, it doesn’t matter how its understood, just how well the predictions check out.
So you’re okay with my believing that there are fairies in my oven, as long as the cake turns out tasty.

No, at least I would not accept that as a theory myself; tastiness is a subjective measurement and we use Occam’s razor to rule out the ever-potentially-present fairy arguments (which have no predictive power. For example, I could counter-predict bad-tasting cake and search around for a snobby gourmet to claim bad taste as an outcome).

However, I am okay (but not happy) with things like “the actual slit the electron goes through cannot be known without destroying the interference pattern” and absolutely nebulous, poorly defined concepts of “wavefunction collapse when the measurement is made”, because every quantum calculation which has been tested that Im aware of has checked out to extreme precision. These are aspects of QM theory where it is often stated: there is no understanding here. Shut up and calculate. And QM a damn good theory; its been tested a hell of a lot more than GR.

That our understanding has changed doesn’t have any bearing on proof in this case.
I absolutely and utterly disagree. Since my entire point was about Newton’s *understanding* of what was going on, the fact that our understanding has changed *is* the proof in this case (although I would prefer to avoid the word “proof”).

This I do have to take exception with. As beautiful and seductive a theory as General Relativity is—and it is absolutely beautiful and one of the most wonderful achievements of humankind— all we can really assert about it is (1) its beauty & simplicity and (2) its contingent of testable phenomena and how well it performs in those tests. At no point can we argue that GR understanding is the real underlying reality. (2) is where the rubber meets the road. There’s a big difference between a new theoretical understanding that leads to new and more testable phenomena, verses a new, simpler theory that makes no new testable predictions. GR is superior to Newton’s UG because of (2) – a host of observed phenomena. Maybe we like it better because of (1) (at least I do), but (2) makes it the current winner. Thats different from something like Hamiltonian or Lagrangian formulations of mechanics— while they provide new understandings, as nice and useful as they are, we couldn’t really argue that the laws of nature were more Hamiltonian mechanics than classical.

Regarding GPS and gravitational redshift, the system relies on GR corrections for the timing difference between the Earth’s surface and the GPS satellites high in orbit, no? On the ground, the most a person could reasonably expect to see is a few nanoseconds/day difference between mountaintops and sea level. I’m not aware of a hand-held unit that is capable of displaying that small of a time difference (unless you wait around and integrate for years). Thats what I mean by outside our normal experience— while the GPS system uses GR corrections, it is difficult for us to personally tell if the redshift is even there, without using a couple of very fancy atomic clocks.

Followup on the WSJ climate denial OpEd

into the search box – published here October 7th, 2011 11:30 AM.