Horton Hears a Who

[eggo]

We all know, that atoms are made of a nucleus and some orbiting particles (electrons), and that solar systems are made of a nucleus (a star) and some orbiting particles (planets), and that the milky way (no candy bar jokes) is made up of a nucleus of densely packed stars (solar systems?) and two spiral arms made of, you guessed it, orbiting particles (stars\solar systems). my question is, how far up (or down) does this pattern go? are galaxies just particles that are orbiting a larger mass at the center? are quarks (sp?) just the nucleus from which we have freed the tiny planets? are we ravaging some unknown solar system (not just our own) when we split an atom? are we made of tiny galaxies? are we just atoms in some guy's hand as he is posting to a message board? am i getting to dramatic? will i ever stop?

eggo

[Ringo]

I'm fixin' to hit the rack and I run up on this question. I've gotta think about it (fractals?) and I really hope in this case that UDD will have it all resolved next time I get to check in. But it's a good question.

[Omniscient]

Not all galaxies rotate or have defined centers, and based on the extremely small sample its foolish to assume that solar systems generally are orbital as ours is.

[eggo]

quote:
Not all galaxies rotate or have defined centers, and based on the extremely small sample its foolish to assume that solar systems generally are orbital as ours is.


no.... have you ever seen that deep space picture taken by hubble (the telescope not the guy)? there are over 3000 galaxies in that one picture and most of them are spiral. i think that is one reason that picture is so revolutionary, until then most galaxies we knew of were amorphous (no definate shape).

eggo

[Omniscient]

Do you have a point your clumsily trying to make???? Most are, but not all. So the premise is pretty weak.

[Nickrz]

An explanation of the Hubble classification of galaxy shapes/types can be found here:

http://csep10.phys.utk.edu/astr162/lect/galaxies/hubble.html

[Boris B]

I love this kind of topic, since it's sort of between physics and philosophy (physics untempered by philosophy tends to make my mind compress along its vector, or at least appear to).

I thought of this neat pattern once, and was disappointed to learn that electrons aren't really considered to orbit nuclei any more. They are more considered to exist in clouds around the nucleus, and we can't ever put our finger on where they are for Heisenberg's reasons (which start to compress my brain as mentioned above).

I don't think the "electron cloud" factor really invalidates the pattern though. Stuff tends to attract other stuff, through the gravitational force, the electro-magnetic force, the strong force, the weak force, the funky-ass octave bass force (okay I made the one up). These forces are analogous in some ways, and different in others. One question I've often had is, if electrons are magnetically attracted to positively-charged nuclei, why don't they eventually run out of whatever energy it is that keeps them from falling into the nuclei? Isn't friction going to eventually cause the planets to fall into lower and lower orbits, and hit the sun (the sun will probably become a red giant first, but that's not the point)?

[eggo]

well maybe those irregular galaxies are atoms that got split in half. so there.

eggo

[Undead Dude]

I think galaxies are the largest entities that have a distinct center. There are larger entities (like clusters), but those don't have a specific center that the rest orbits around.

One question I've often had is, if electrons are magnetically attracted to positively-charged nuclei, why don't they eventually run out of whatever energy it is
that keeps them from falling into the nuclei? -- Boris B
For an electron, the so called "ground state" orbital is a state of rest. The wave nature of the electron will keep it from falling further. If it was "pushed" a little bit closer, that would actually be a higher energy state, and it would bounce back (unless it was pushed hard enough to actually impact it into the nucleus).

Isn't friction going to eventually cause the planets to fall into lower and lower orbits, and hit the sun (the sun will probably become a red giant first, but that's not the point)? -- Boris B
Well, the planets don't experience friction in the normal sense. The planets aren't moving in a fluid. Particles that strike the planets could come from any direction, so they wouldn't cause a dampening effect.

However, gravitational radiation (energy carried off by gravitation waves) would cause the orbit to decay very, very, very, very, very, very slowly.

[Undead Dude]

are we ravaging some unknown solar system (not just our own) when we split an atom? are we made of tiny galaxies? are we just atoms in some guy's hand as he is posting to a message board? -- eggo

Much to the chagrin of stoned people everywhere, I think what Boris said covers the small end pretty well. The electron attached to an atom nucleus bares almost no resemblance to a planet orbiting a star. About the only thing they have in common is that there is a little object keeping close but not hitting a bigger object. The fact that their configurations are usually called "orbitals" is a pretty misleading term.

Quarks don't have anything to contribute to the comparison. Quarks exist in groups of 2 or 3 to form many of the particles that we can observe. There is no centrality or anything even vaguely resembling an orbit on the quark level.

[TubaDiva]

I meant what I said and I said what I meant,
I'm completely confused now -- 100 percent.

your humble TubaDiva/SDStaffDiv
for the Straight Dope
'cause I don't get the connection.
(I HATE it when I don't get the joke!)

[Undead Dude]

Now watch me explain the totally wrong thing :)

The connection to this idea and stoned people?

Well, my main inspiration for saying that was the movie Animal House. This specific idea was laid out by one of the main character's prof's as they got stoned with him.

But in general, many stoned people can often be entertained by some of the wilder ideas in physics. :)

[moriah]

Sub-atomic particles lose analogies to planets because:

they don't have Newtonian orbits

they are governed by quantam mechanics and the Heisenbergian uncertainty principle

particular types of particles are completely indistinguishable from each other (Jupiter and Earth have distict characteristics; one electron and another don't)


So, if there are real Whovians in Whoville, they're incomprehensibly different from us and most likely indistinguishable from each other.


Peace.

Well, the planets don't experience friction in the normal sense. The planets aren't moving in a fluid. Particles that strike the planets could come from any direction, so they wouldn't cause a dampening effect.

That's not strictly true, is it? If a planet were at rest the particles striking it would be equally distributed in all directions. But a planet that is moving is more likely to collide with particles in the path of its movement.

[Northern Piper]

there's an article in this month's Scientific American that discusses the issue of changes to planetary orbits caused by impact with planetoids - planetismials - small chunks of stuff.

The author's theory is that these impacts affected the orbits of the gas giants in the early stages of the solar system. She argues that Jupiter's orbit has contracted slightly as a result, while the orbits of Saturn, Uranus and Neptune have all expanded.

One of the interesting side-features of her article is its relation to the "Is Pluto a Planet?" issue. She theorises that Pluto originally had a typical elliptical orbit, on the same plane as the other planets, and did out cross Neptune's orbit. She argues that the expansion of Neptune's orbit triggered the unusual features of Pluto's orbit. If correct, this suggests that Pluto is truly a planet, not a captured body.

[Northern Piper]

correction: "did not cross Neptune's orbit"

[Undead Dude]

But a planet that is moving is more likely to collide with particles in the path of its movement. -- Mike King
Aha, but moving relative to what? The Sun? The solar wind tends to push out, so it certainly wouldn't cause a decaying orbit. Particles near the Earth that are native to the solar system would orbit in a fashion comparable to that of the Earth. Partcles from outside of the solar system aren't going to be coming from the same reference frame as the solar system, so we can't really descrive the Earth as moving compared to those particles as a whole.