Posted on 06/14/2007 8:50:35 PM PDT by annie laurie
Why would I want to converse with someone not in charge of their own life? May as well talk to a toaster with attitude.
What's wrong with this question? Do you mean to say that 'dark matter' is every where in the universe but Earth?
L
I leave disappointed
youre welcome to the last word
.....yes, yes, I know, "dont leave disappointed...just leave"
the peanut gallery is yours for the evening
Cerebral vs creationism... nah. Too easy. You have a good night, and don’t forget to empty the crumb tray.
I guess you are better at theory than practical problem solving. In your scaled-down model, you neglected some very important physics concepts, namely the role of mass. If your example was even remotely correct, and dust motes have not graviational effeet on each other, then what is holding the galaxy together? And planets are a heck of a lot smaller than stars so what is keeping them in their orbits? Angels pushing stars and planets around?
No.
You failed to account for the scaled mass of the sun and the r^2 distance dependence of gravity. To model the scale experiment correctly, the mass of the sun-dust mote would be about 57 metric tons.
And if you were to have a dust mote sized model, why wouldn't there be any interaction? What other forced would swamp gravity? I don't know of any that have the same long distance effects as gravity does.
What's wrong with this question? Do you mean to say that 'dark matter' is every where in the universe but Earth?
L
Dark matter has mass, but it does not interact with regular matter. Sure, the stuff may be splashing through the Earth all the time, but since it has no interactions with regular matter, you'd never notice it except for effects related directly to mass. The only force mass can exhibit is gravity. You can't see it with light because it has no eletromagnetic interations. Same reason why regular matter can't capture or bond with it. It has no chemical interactions, which is based entirely on electromagnetism. It has no nuclear interactions either, other wise nuclear effects could be observed. The stuff appears to have only mass interactions.
So to answer the question directly, the stuff could be passing right through you and you'd never know it. It would never pile up on your carpet because there is nothing to hold it on your carpet. And you could not vacuum it up because suction, via air movements, would have no effect on it either.
It is only detectable by it's gravitational effects on matter. In othr words, we see things moving and the pattern of the motion indicates a gravitational effect of a certain magnitued and in a certain location, but there is nothing visible where it should be. Without dark matter, things in the universe would not be moving the way they are. These are highly quantifiable parameters that are involved and not some kind of guess.
So let me get this straight. It has mass, which means it must have gravity. Right?
The only force mass can exhibit is gravity
OK, so it has gravity. That must mean that it's attracted by gravity to other objects that have mass. Like my carpet.
The stuff appears to have only mass interactions.
OK I get it. Here's where you lose me:
It would never pile up on your carpet because there is nothing to hold it on your carpet
My carpet doesn't have gravity? Earth has gravity. My carpet is on Earth. Therefore my carpet has gravity. Therefore this 'dark matter' stuff must be on my carpet.
These are highly quantifiable parameters that are involved and not some kind of guess.
Bull. There's stuff going on you scientists can't explain so you made up this 'dark matter' hooey and pounded on your little theory hard enough to make it 'do' what you see happening. That doesn't 'prove' anything.
L
Mainly electrical and electromagnetic forces, which are many orders of magnitude more powerful than gravity.
The sun and Alpha Cent actually don’t have much of a gravitational effect on each other. But, there are 100 billion other stars and a lot of other things in the same system, so just looking at those two gravitating bodies would probably not give a satisfactory explanation of what is going on.
Apparently from what I read, even in the case of star clusters in which the light of the stars unifies, the distances between any two stars are not that much different than that between our sun and AC.
While most stars appear to be binary, that is, two orbiting their combined center of mass, most stars would be well beyond their relative escape velocities from most other stars. They all, inside the galaxy, orbit a center of mass; the problem: that mass is not a simple point center but some kind of figure like a disk. You might be interested in this from a math point of view. Dark matter is one possible explanation, but a modification to theory of gravitational fields is open to development.
Also, if '95%' of the Universe is this dark matter stuff, and the only quality it has is mass and gravity, how come we aren't all being crushed to death by stuff we can't see?
I mean eventually enough of the mass from this invisible, undetectable stuff would be drawn to Earth by our gravity that we would all be getting heavier over time. Right?
L
Although the mass represented by the dark matter hypothesis, and it is only a hypothesis, is large, it would only represent a few more stars in our neighborhood if we could see it. Most of near sunspace would still be empty.
If you wish to model the galaxy motion by individual stars you will quickly come to a computability problem, but if you model it by the gravitational field the problem is immensely simpler. Still, a modification to the inverse square format of the gravity field might also produce a solution. So, a chance to try some calculus.
Our solar system by all acounts works very nicely without dark matter and you have to assume that if you add dark matter equivalent to 20 times the mass of the observable bodies in our system into our system, the rest of it would cease working according to the mathematical models which Kepler, Newton et. al. so graciously provided us with.
What we have here is something like Cotton Mather's invisible world wonders or the emperor's new suit of clothes, i.e. the stuff is 95% of the universe EXCEPT in our own solar system where we could have any experience with it.
You really are pig ignorant about physics. So all of Newton's and Einstein's work is wrong! Laughable! Gravity is solely attractive. Mass is attracted to mass. Electromagnetic forces can be attractive and repellant. But for astonomical bodies on astronomical scales, it's all attractive forces that have been observed. In any system with more than 2 bodies, if electromagnetic forces were involved, then at least one body would be repulsive in nature!
Not only that but gravity is the dominant force over astronomical distances. The magnitude of a charged system, either electrically or magnetically, would have to be multiple orders of magnitude different than what actually exists in nature in order to have any effect. Only on very small scales does electromagnetism trump gravity.
No, that is incorrect. The scale is such that we would hardly notice dark matter accumulating on our tables and windowsills. Order of magnitude rules.
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