How Does The Universe Work?

[Lightknight924]

How come every picture I ever see of a galaxy has a glowing center? Wouldn't that mean there's a gigantic star in the center? Or is it many star clusters forming on large super cluster that revolves around a massive black hole?

[Reach]

Well, looking at it logically, it should come stars and hot gas, but the reason it's so bright in the center is probably the gas. The gas and dust is going to absorb a lot of the visible light so you can't see through it. If you were to look at a galaxy in another spectra I'm sure it would not like like that in the center.

There is still a black hole at the center. Huge...like, probably 5 million times as big as the sun. lol

[flamingspinach]

Originally Posted by Reach

WTF? Everything is a theory? Since when? That's simply not true.

Our minds have no direct contact with reality? What on earth are you going on about now. Prove this? What is reality? You could define it infinitely, therefor this statement is meaningless.

And I think infinity is a pretty impossible to comprehend, since you can't exactly put measure to something that countinues without bounds, you can understand it's meaning but it's not exactly something tangable. Also, to say our math can properly measure infinity is a little iffy in some cases. Mathematics break down at planck length, are equations make no sense when explaining something infinitely small (alteast equations that don't involve radical untested theories :P)

OK - everything is a theory because nothing is provable without premises, and all premises are assumptions. Simple. Our minds have no direct contact with reality because all information we gather is due to the propagation of interactions with reality (or so we assume, as part of the universal axioms we use to cope with our sensory inputs) rather than with direct measurement of reality. This is especially true at extremely high magnifications - for example, particle accelerators infer the existence and properties of rare particles by measuring the propagated effects of the products of their decay upon banks of sensors around the point of impact.

As for infinity, by mathematics I mean pure mathematics, obviously, not applied mathematics. "Mathematics break down at planck length" - uh, this is simply not true, nor does it make any sense. Mathematics doesn't "break down" anywhere because it isn't anywhere.

-fs

[Reach]

OK - everything is a theory because nothing is provable without premises

completely false under the definition of a theory.

Rest is assumptions. "Proof" and "Reality" are non tangable words that have arbitrary definitions. Don't use them unless you have to. I could define reality such that it is only what is possible through my interactions with everything I perceive to exist, making whatever you went on about again, meaningless.

Mathematics breaking down at planck length is a 'saying' as I would call it. If you would like a more direct answers, mathematics give incorrect answers at planck length.

Then again, I could say you got me because I'll make the assumption your use of the word 'theory' is also a generalized 'saying'. XD

And to say mathematics isn't 'anywhere' isn't necessarily true, since mathematics is defined by us, anything can be expressed in terms of math and therefor it exists everywhere as defined by us.

Oh the wonderful game of definition.

[aperson]

Originally Posted by Reach

And I think infinity is a pretty impossible to comprehend, since you can't exactly put measure to something that countinues without bounds, you can understand it's meaning but it's not exactly something tangable. Also, to say our math can properly measure infinity is a little iffy in some cases. Mathematics break down at planck length, are equations make no sense when explaining something infinitely small (alteast equations that don't involve radical untested theories :P)

Reach, we have a pretty good grasp of the infinite and the infinitesimal. A lot of our equations in physics are built off of integrating the infinitesimal over some bounds... just look at int[E*dA]. dA is an infinitesimally small area vector.

The only thing that makes them a bit difficult to comprehend is that the infinite and the infinitesimal do not lie on the realspace, they are hypperreal numbers. Because Euclidean space is very similar to R^3 space, we have some basic difficulty comprehending things that lie outside of this realspace.

[flamingspinach]

Originally Posted by Reach

completely false under the definition of a theory.

Rest is assumptions. "Proof" and "Reality" are non tangable words that have arbitrary definitions. Don't use them unless you have to. I could define reality such that it is only what is possible through my interactions with everything I perceive to exist, making whatever you went on about again, meaningless.

Mathematics breaking down at planck length is a 'saying' as I would call it. If you would like a more direct answers, mathematics give incorrect answers at planck length.

Then again, I could say you got me because I'll make the assumption your use of the word 'theory' is also a generalized 'saying'. XD

And to say mathematics isn't 'anywhere' isn't necessarily true, since mathematics is defined by us, anything can be expressed in terms of math and therefor it exists everywhere as defined by us.

Oh the wonderful game of definition.

Sorry to be petty, but your misspelling of "tangible" was getting annoying

Now that that's over - um, pretty much anyone will agree that "reality" is "that which is objectively true". A logical "proof" is by universal definition a logical argument that uses axiomatic laws upon premises to show the validity of a conclusion. Mathematics doesn't "give answers", correct or incorrect. Not to mention that in pure mathematics there is no definition of "correct" or "incorrect" - only "valid" and "invalid", when you're working on subjective inputs. I think you're misunderstanding what exactly mathematics is - perhaps you're thinking of quantitative measurement? :/ By saying that mathematics "isn't anywhere" I mean that it is not fundamentally connected to physical reality.

-fs

[Reach]

This discussion is fairly irrelevant. It's hard to make ground here.

I tend to misspell tangible for some reason. Sue me, you know what I mean,

There is a section of philosophy that deals with the proof of knowledge. You can certainly be correct with math. There are correct answers within itself. I define 1+1 to be 2 therefor the answer is correct. Saying otherwise is being overanalytical or ****ing with the definition of the words.

This is just all one big mess, and I won't be posting on this specific topic anymore XD It's all assumption and unproveable words that don't go anywhere. Not to mention there's a bunch of noise in teh background and I can't concentrate.

[foolface06]

Read "A Sense of the Mysterious". Alan Lightman really elaborates on some of these topics. It helped me to understand the universe much better. But I forgot about it all since Katrina. Plus I just graduated from high school. I wrote an essay on it (I think) *searches for essay*.

[T0rajir0u]

Originally Posted by Reach

This is just all one big mess, and I won't be posting on this specific topic anymore XD It's all assumption and unproveable words that don't go anywhere.

smartest statement in the entire thread

[flamingspinach]

Considering that it followed the statement that "Mathematics break down at planck length", or even worse that "equations make no sense when explaining something infinitely small" (uh, that's sort of the foundation of calculus >_>), I find it diminishes greatly in stature.

[djreality14]

Originally Posted by Reach

3. Gravity is, basically, cause by bends in the space time fabric. I mean, it happens because energy within space causes causes distortions within it, or a dip for example. We revolve around the sun because, essentially the sun is creating a larger dip and gravitational pull which the earth falls into. To see gravity on an extreme scale, look at a black hole. To understand one in a simple sense, it is a hole or 'dip' in the space fabric that extends doward infinitely, so you can imagine what would happen if you got too close (event horizon).

Wait a minute... If the sun is creating a large dip in the fabric, why don't we eventually roll into the sun? What force is pushing us, and the other planets, forward to negate the force pulling us towards the sun?

EDIT:

Originally Posted by Lightknight924

How come every picture I ever see of a galaxy has a glowing center? Wouldn't that mean there's a gigantic star in the center? Or is it many star clusters forming on large super cluster that revolves around a massive black hole?

If we were revolving around a massive black hole, could that possibly explain the theory that the universe is shrinking?

[flamingspinach]

1) That's called, um, principles of uniform circular motion. Simple Newtonian physics. Something going around in a circle is constantly changing direction, but not speed. Since velocity is a combination of direction and speed, the velocity is constantly changing, which means there is an acceleration being effected upon the object. This acceleration times the mass of the object is equal to the "centripetal force", which is a constant force exerted on the object always directed towards the center of the circle. In the case of a gravitational orbit, this centripetal force is the force of gravity. Since the force of gravity follows the inverse square law, this can also allow for elliptical orbits.

2) The universe is not shrinking. Also there is no center of the universe, as far as we know, and the giant black hole thing refers to the center of our particular galaxy, not the universe itself.

[Moogy]

Question: How does the universe work?

Answer: It doesn't.

[Reach]

Also Djreality, remember, these curves in space time arn't real. It's a mathematical fabric to create something tangible ( ) out of something abstract and untangible. General relativity is absolutely NOT correct, however, it's created fabric does make extremely good predictions abotu what will happen.

Rest is what flaming said. And the universe is expanding at an accelerating rate.

I notice you make a big deal about me saying 'the math breaks down' and such, yet you wouldn't make a deal when I say space fabric? Why? You do realize both are said because it's easy to understand? Why would I overcomplicate things when I can say them so that they make sense? I don't need to go about explaining undefined solutions and people arguing over whether or not they are possible XD

Not to mention many physicists use the same terminology. Einstein, and people like brian greene are famous not because they use the most 'correct' terminology, but because what they say makes sense. Whatever you're going on about is ridiculous and irrelevant. Calculus and what is actually occuring in nature don't always agree with eachother. Calculus is the foundation for much of mathematics, but maybe Calculus is the problem. If it wasn't we wouldn't have so many different god damn theories to explain things that make absolutely no sense under certain forms of mathematics, with each of these theories disagreeing with what many other ones are saying.

The universe is so complex it is impossible to properly model under any of our little theories. I'm sure one day it will be possible, but there's going to be a lot of overhaul on what we think we know.

[msbrunnettemickey]

For your question you should read the book 'The Maybe Universe' and/or 'Jonathan Edwards: Philosophical Theologian'.

They talked about Isaac Newton and stuff. Heh.

Edit: Some sentence from the book:

"Centuries later Isaac Newton appeared and extended the well-known earth force, gravity, out into the solar system, and the force, or method, of interacting, known as universal gravitation was born."

[flamingspinach]

Reach, um, the fabric of spacetime is a metaphor, and is perfectly fine to use. Saying that "math breaks down" just shows that you're uninformed. And wishing that higher math would just go away so we wouldn't have such complicated theories just seems like a plaintive excuse. I have to ask, how much math do you even know?

And what do you mean by "the curvature of spacetime isn't real"? It's as real as quarks and gluons are, because the currently accepted theory posits their existence. I'm not sure what exactly you're getting at there.

-fs