Compacting universe before big bang?

[Whitney]

laetus, you signature says:

"Generally speaking, the errors in religion are dangerous; those in philosophy only ridiculous”

And what of those in atheism, in your view?

How could atheism have multiple errors when it is simply a statement of non-belief?

[MommaSquid]

laetus, you signature says:

"Generally speaking, the errors in religion are dangerous; those in philosophy only ridiculous”

And what of those in atheism, in your view?

Onlyme's Random Questions thread was started for a reason.   Use it!


http://www.happyatheistforum.com/ftopic143.html

[Asmodean Prime]

Ah, wikipedia

The fount of all knowledge

Not that the Oxford English dictionary is a world class standard?
Not that wikipedia is edited by anyone and everyone who has something to say?

Never mind.

[Aullios]

But why so odd, aullios?

Usually dictionaries don't use definitions that may be misconstrued by an interpretational difference.  It's the first time I've seen it happen.

[McQ]

But why so odd, aullios?

Usually dictionaries don't use definitions that may be misconstrued by an interpretational difference.  It's the first time I've seen it happen.

Aullios,
Dictionaries, especially good ones like the OED, use ALL definitions of any given word, which is why people are able to pick the one they want from the listing and ignore the others in the listing. I have three different dictionaries at home, and found four online, including the OE Compact Dictionary. ALL of them list gravilty as a force, or a fundamental force in their listings, usually as the first listing.

They also list things for gravity like: solemnity, importance, seriousness, difficult situation, etc as definitions.

See what I mean? You can cherry pick the definition you want, especially if you want to misuse the wrong definition and ignore the correct one for the context in which you are talking. Not that anyone here would do that, of course.  :wink:

[Whitney]

McQ...I couldn't find the quote...but earlier in this thread I think you made a statement about an atom not being like a tiny universe.  That's the type of model I was taught in high school chemistry...do you know of a source that explains how they actually work?

[McQ]

McQ...I couldn't find the quote...but earlier in this thread I think you made a statement about an atom not being like a tiny universe.  That's the type of model I was taught in high school chemistry...do you know of a source that explains how they actually work?

Right, laetusathoes. I made mention that atoms aren't like tiny solar systems. I was taught that they were that way in school  as well. In college physics they elaborated on atomic structure.

Here's the thing with that: The Bohr Model is a great way for us to visualize atoms and the interaction of the electrons. It's easy to draw. It's easy to understand. And electrons do "orbit" or spin, so-to-speak.

But electrons, like photons, act both as particles and as waves, so in reality, and electron isn't like a small ball orbiting an atomic nucleus. It's more like a cloud surrounding the nucleus. The Bohr Model is only useful for simple atoms, then you need to use the Wave (or Quantum) Model to describe complex atoms.

This ties in Heisenberg's Uncertainty Principle, which tells us  that you cannot know the precise location and momentum (mass times velocity) of a subatomic particle. A couple of sites with pics and descriptions of the Bohr model and/or Wave Model:

http://web.jjay.cuny.edu/~acarpi/NSC/3-atoms.htm

http://www.nyu.edu/pages/mathmol/textbook/atoms.html

http://www.aip.org/history/heisenberg/p08.htm

Does that make sense? I'm not sure if I answered your question entirely. Let me know. (EDIT: Wanted to add a source) Byt the way, the "Dummies" series of books are good for a lot of subjects, and the "Physics for Dummies" is really good. No offense! LOL! In keeping with that, the "Complete Idiot's Guide to Physics" is also very good. One of my favorite books, as well as one of my most used by my family (and some friends), is "Basic Physics", by Karl F. Kuhn. It's a self-teaching guide. I recommend it highly for anyone who wants to learn the basics, or is going on to study physics and science in school.

[Aullios]

Most textbooks use the Bohr model because it's tough to grasp the Heisenberg Uncertainty Principle, especially in a high school physics class.

You can see that from McQ's explanation.

McQ:
Isn't the electron still a subatomic particle, but the "cloud" is just the area of probability where the electron may be?  I haven't heard of the electron itself being a cloud before.

[McQ]

Most textbooks use the Bohr model because it's tough to grasp the Heisenberg Uncertainty Principle, especially in a high school physics class.

You can see that from McQ's explanation.

McQ:
Isn't the electron still a subatomic particle, but the "cloud" is just the area of probability where the electron may be?  I haven't heard of the electron itself being a cloud before.

Yes.

Here I'll clarify my analogy, because it was confusing. Sorry. The electron isn't actually a  cloud (I don't think I said it was actually a cloud, but like one), it is akin to, or like a cloud, because it is a wave, in addition to being a particle.

Just as a photons in the "double slit" experiments act as particles and waves. http://en.wikipedia.org/wiki/Double-slit_experiment

(Wikipedia...a source I check carefully for accuracy before using, explains this nicely)

It's totally counterintuitive! LOL! But it accurately describes and predicts behavior at the subatomic level.

What I love is when Richard Feynman got into all this, he really turned QED around. His Feynman diagrams are so simple looking (deceptive, they describe complexity that is beyond me). I especially love his "Sum Over Paths" that says a photon, or an electron not only occupies many different possible paths, but ALL possible paths on it's merry way somewhere. It really comes out the same as the Probability Wave idea mathematically, but gives a different way to look at it. Did the can of worms just open wide? LOL!

[Whitney]

That makes sense.  To make sure I understand correctly I'm going to state how I understand the electron nucleus relation:  So, the electron does kinda spin around the nucleus....just not in a standard path like illustrated by Bohr model.  Because it doesn't have a standard path, the path is better illustrated by a cloud (rather than circular orbits like we use to illustrate planetary motion).  Is that right?

no offense taken...I like the dummies/idiot's series too (they keep things simple).  Unfortunately my physics eduaction hasn't been top notch and I haven't been around much chemistry since high school.  I'm determined that one day I'll undestand string and m theory (as much as possibe for a layman)...but, anything dealing with quantum physics is kinda confusing for me...Especially since I'm a visual learner, if I can't see it, I have a hard time understanding it.

[McQ]

Apologies for posting so quickly and with poor clarity. I'm supposed to be working, and not screwing around in here! LOL! I'm trying to multitask. It's not working out so hot. Back to work for a while.

[McQ]

That makes sense.  To make sure I understand correctly I'm going to state how I understand the electron nucleus relation:  So, the electron does kinda spin around the nucleus....just not in a standard path like illustrated by Bohr model.  Because it doesn't have a standard path, the path is better illustrated by a cloud (rather than circular orbits like we use to illustrate planetary motion).  Is that right?

no offense taken...I like the dummies/idiot's series too (they keep things simple).  Unfortunately my physics eduaction hasn't been top notch and I haven't been around much chemistry since high school.  I'm determined that one day I'll undestand string and m theory (as much as possibe for a layman)...but, anything dealing with quantum physics is kinda confusing for me...Especially since I'm a visual learner, if I can't see it, I have a hard time understanding it.

Yep, the electrons are in an "orbit" around the center of the atom. This link gives a nice visualization. The "cloud" is a way to visualize the wave function of the electron. My only problem in their description offhand is that they use the term centrifugal force incorrectly. It's a pet peeve. Centrifugal Force is not a real force, it is a "virtual" force. Centripetal force is the real force. Anyway, that's a whole 'nother thing!

EDIT: That reminds me. If the electromagnetic force wasn't actually a force, there would be no atoms. So if anyone tells you it's not a force, then watch them closely, because they will immediately disintegrate. It should be cool. :-)

[iplaw]

McQ.

As far as I remember those terms are just placeholders to help people distinguish different force behaviors.  It's easier to just say centripetal force than to talk about angular momentum and multiaxial forces.  When it comes down to it it's just combinations of interacting x,y,z "lateral" motion am I correct?  It's been a long time since Dynamics and Physics III for me.

[Court]

I'm pretty sure we learned both of those models in my chemistry class, the Bohr model just for simplicity. It was explained, however, that the electron doesn't use a standard path and that is best visualized as the "cloud" in the other model. We didn't go much into the wave function, though...

[McQ]

McQ.

As far as I remember those terms are just placeholders to help people distinguish different force behaviors.  It's easier to just say centripetal force than to talk about angular momentum and multiaxial forces.  When it comes down to it it's just combinations of interacting x,y,z "lateral" motion am I correct?  It's been a long time since Dynamics and Physics III for me.

I keep popping in here when I'm supposed to be working. Nobody tell on me! LOL! iplaw, Centripetal Force is the correct term which describes the force on an object in accelerated motion, or motion in a curved path. It literally means, "center seeking", because that's the way it acts on objects. It is directed toward the center of the curve of the path.
Circular Motion, Angular Momentum, Rotational Motion, Angular Velocities are all in the picture, as well as a host of other things. You seem to remember it pretty darn well.
Ok, I really have to work steady now, for the next two hours!