Science!

[Umbran]

I have to disagree with that.

Dude. Celestial deferent and epicycle spheres, an another sphere with the stars upon it. Ptolemy's estimates for distance to the various planets were generally off by an order of magnitude and more. It was wrong.

The Antikythera mechanism is an ancient mechanical computer that calculates the positions of the solar system.

Yes, but a doctor can give you willow bark tea to relieve pain, while still working with a model that says your humors are out of balance, and not washing their hands before surgery.

The Antikythera mechanism could only predict the positions of the major planets for which they had long periods of observation, and extrapolate that into the future. They could not predict the motions of celestial objects not originally in their catalogue - like, say comets. It was not, in fact, a general model of motion.

Impressive? Sure. An accurate model? No.

 

[Nikosandros]

Dude. Celestial deferent and epicycle spheres, an another sphere with the stars upon it. Ptolemy's estimates for distance to the various planets were generally off by an order of magnitude and more. It was wrong.

Ptolemy's system purpose was to calculate the motion of the planets as seen from Earth. As such it worked much better than Copernicus system (as Copernicus himself acknowledged). As you note, the huge problem with Ptolemy's system is that it is non-universal. All the calculations work only in the specified case and would need to be re-done from scratch in a different star system or for previously unobserved celestial bodies.

As an aside, the deferents and epicicles are a way to approximate periodic motions by summing uniform circular motions... the same idea behind a Fourier expansion.

 

[shawnhcorey]

The reason the Copernicus system didn't work was because Copernicus had the planets moving in circular orbits at constant speed. It was not until Kepler changed the orbits to ellipses and varied the speed of the planets did the heliocentric system work.

 

[Nikosandros]

The reason the Copernicus system didn't work was because Copernicus had the planets moving in circular orbits at constant speed. It was not until Kepler changed the orbits to ellipses and varied the speed of the planets did the heliocentric system work.

Yes, naturally. But Copernicus' system is the beginning of a universal system, one that can give rise to a theory of motion.

 

[freyar]

Wow, I'm kind of sorry I added anything to the thread. How did we get on the Ptolemaic vs Copernican models? That's not really analogous to the muon g-2 measurement.

As others have noted, the shift between Ptolemaic and Copernican/Keplerian/Newtonian systems is not really geocentrism vs heliocentrism. It's that heliocentrism makes use of the more natural language, which in turn aids theoretical understanding, which actually allows you to make predictions (that's why the Newtonian part is so important!). They're two different frameworks. Ptolemy described planetary motions by fiat. Newton actually gave you a set of laws that explain planetary motion.

The current situation with the muon is very different. If the Standard Model prediction and experimental measurement are in fact different*, the resolution doesn't require any sort of change in framework. It just needs a new type of fundamental particle or maybe a few. And there are plenty of other reasons to believe that we need more anyway. It's worth noting that the measurement and prediction are quite close:
experiment: 2.00233184122
vs prediction: 2.00233183620

*See my first post: there are reasons to think the Standard Model might actually predict the experimental results correctly anyway, if we know how to do the math correctly.

 

[shawnhcorey]

Every time someone says the Standard Model is incomplete, I wonder if future generations will think us naïve for using it. After all, that's what we think of the geocentric model.

 

[freyar]

Every time someone says the Standard Model is incomplete, I wonder if future generations will think us naïve for using it. After all, that's what we think of the geocentric model.

If future generations are smart enough to think the Standard Model is "naive," they will know enough about science to know that the Standard Model has a very wide range of validity. They won't think it naive any more than we think it naive to use Newtonian mechanics rather than special relativity to describe the path of a thrown ball, for example.

The Ptolemaic model is very different because it was descriptive only and not explanatory.

 

[Umbran]

Every time someone says the Standard Model is incomplete, I wonder if future generations will think us naïve for using it. After all, that's what we think of the geocentric model.

It is not, however, what we think of Newton, even though Einstein showed his work to be incomplete. We still use Newton every day.

 

[aco175]

I realized 3 things from this thread;

1: Man, I'm stupid compared to some of you
2: Am I the only one that needed to Google what a muon is?
3: Did I help pay for the 100 million to figure this out? I guess money better spent than some of the other things my government does.

 

[Dannyalcatraz]

I can say that if you live in any “1st world” country, some of your tax dollars went to subatomic particle research, dierectly or indirectly.

i can also admit that I have heard of muons before I posted this, but didn’t know precisely what they were. I did know, however, that they were not the smallest particles involved in cows’ sound making.