Wednesday, May 14, 2014

Our Inadequately Understood Universe


Here's quite a nice overview of the computer model built at MIT to recreate thirteen billion years of the evolution of the universe.

Very pretty stuff.

But more and more I find myself thinking of celestial spheres.  In classical times it was thought that the stars all rested on the surface of a sphere.  The complex motions of the planets were explained by assuming that each was embedded in its own, independently moving transparent sphere.  (Made of quintessence -- but let's not go there today.)

This system worked well enough, particularly after Copernicus placed the Sun at the center of everything.  But only just well enough.  As the measurements of planetary orbits got better and better, deviance from predicted results had to be explained away.  To the orderly cycles were added epicycles and eccentrics.  Angels were recruited to keep the things spinning.  The machinery kept getting more and more complicated.

Meanwhile, troublemakers like Tycho Brahe discovered that comets passed effortlessly through these supposedly crystal spheres.

It wasn't until Johannes Kepler scrapped the entire system (well, almost all -- he kept the outermost celestial sphere so the stars would have a place to perch on) in favor of celestial mechanics that it all made sense again.

So every time I hear about the necessity of dark matter to make the numbers line up right, or the need for dark energy to explain observed phenomena, or that the rate of expansion for the universe is speeding up, or that in the early stages of cosmic evolution the whole shebang moved faster than the speed of light, or that "Einstein's greatest blunder," the cosmological constant, has been yet again added to or subtracted from our understanding of the Way Things Are . . .

Well.  I just have to wonder if we're not missing something very simple and counterintuitive.

After all, how can the planets keep from falling down if they're not embedded in crystal spheres?

And . . .

Stephen Notley, the cartoonist-creator of Bob the Angry Flower did a much more succinct critique of the currently accepted model of cosmology in a cartoon titled CREATION:  A Science Story.  You can find it here.



David Stone said...

Dark matter always did seem like a cop out. What seems more likely, that astrophysicists are wrong about something, or that a huge percentage of matter in the universe is for all practicle purposes "invisible"?

Edward said...

The simplest answer is that the universe is fake. Narnia, or whatever if you're religious, or some sort of simulation, if you're not. Of course, this just means giving up, so, no, we shouldn't think this. No. But. Yeah. All the things you speak of made think, man, this is absurd. Remember the oscillating universe? Big bang, big crunch, cycling forever… that made perfect sense. I miss that one.

There are some studies claiming to find modeling artifacts, from the simulation, via experiment. Clipping of values that should go infinite. If simulated realities are theoretically possible, then most of us should live in them.

Video game engines have all these stupid tweaks to make playing in them fun. (the ability go move while in free fall during a jump for example, though one can imagine you have jets on your armor or whatever) variable fall damage, all this bullshit stuck in to make the game more fun.

It's not dark matter or energy. It's fun matter and energy.

As long as you don't get angry and write a story about some poor abused child in a giant robotic dragon setting out to kill God, I figure, you're handling it pretty well.

TheOFloinn said...

The eccentrics and deferents were there from the get-go. The idea that Ptolemaic astronomy had to keep adding epicycles is a myth. (Copernicus had more epicycles in his model than Peuerbach's then-current edition of Ptolemy.)

The planets were seen to speed up, slow down, grow larger and brighter, smaller and dimmer. It made sense that they rode on an epicycle. Centuries later, Kepler showed that motion on an epicycle on a deferent was mathematically equivalent to motion on an eclipse.

Ptolemaic astronomy contradicted Aristotelian physics, so it was regarded as pure mathematics whose only purpose was to make accurate calendars and horoscopes. It lasted until the phases of Venus were observed, whereupon everyone went over to the Tychonic model. And that one was mathematically equivalent to the Copernican model! Which meant to choose between them required non-mathematical data.

Dark matter seems to have a lot of the properties that were predicated for the Aristotelian aether. Go figure. Maybe the old Stagirite was on to something...