You are missing one critical issue when you're comparing the scientific element of gravity, to the concept of God -- in relative terms, gravity is a simple act of two objects being pulled together whilst God is supposedly an entity of immense power and intelligence. Intelligence brings in many, many more variables into a test.

While some people who say "God does not exist." have their reasons which are valid; I think that God may just be operating on a person-to-person basis (from reasons which I wont say).

Ok, some very quick answers (I won't have time to say everything I'd want to)

That's the thing. The light comes from objects 13.7Gly distant. It took that long to reach us because the speed of light is constant. Which part didn't you get?

Yes, you are. I'll ask you a simple question: how long does light (given the constancy of the speed of light) take to travel 13.7Gly?

No, it's not. Why'd you think I asked? Think about it: if there is no measurable difference between something existing and something not existing, on what grounds would you claim its existence (note, this is philosophy rather than physics proper)?

You mean, not being able to refer to points outside the universe or before the big bang? There is a reason: the edge of the universe is an event horizon, the big bang is a singular point in space-time. Just as no law in physics can tell you what the inside of a black hole looks like, no law in physics can tell you what the outside of the universe looks like.

And you'd be correct. You can see it on the sky every day. Well, you could if you could see the afore-mentioned microwave background radiation, which is what 13.7Gyr of cosmic expansion has red-shifted the radiation into.

Anyway, a full explanation with all the details filled in of the above probably requires a full course on general relativity and cosmology, something I am neither qualified to give nor have time for, least of all for typing it in on these forums.

You can't prove the positive either. Or formulate a way to test it. In other words, it is untestable. Unprovable. Which gravity is not.

Zeus was the god of thunder.

Primitive people still worship the sun as a god.

They completely describe the probability function of the quantum state.

That's after measuring the particle, after the collapse of the wave function. What I originally talked about is about the state of matter before the collapse of the wave function: matter is in a state of existing/not existing, until observed; hence the famous cat "experiment". Which is similar to back face culling in computer games: the engine does not render all the detail until required.

QM, the origins of the universe, peoples' opinion about the universe, are all related.

When we are talking about the universe, we do not know if it really includes everything. It certainly includes everything made out of matter we know. In the Matrix, people do not know there is something that exists out of the universe they know.

I was under the impression they didn't directly measure the distances of galaxies, but used the redshift to calculate the distance based on the expansion rate. They can use apparent angular size and brightness in a statistical way to show that the small and dim (and supposedly farther away) galaxies have a larger redshift.

And I remember reading about some galaxy that appeared to move faster than light, but someone else showed how this galaxy could be moving away from us at such an angle that the observed position moved faster than the speed of light.

How does it have a shape? How is it expanding? Maybe matter is just shrinking, or shedding material off its atoms to form dark energy.

Well, now we're not talking about light anymore. Now we're just back to the CMB.

Yeah, the parallels are strong, aren't they?

<snip response to axilmar> nm, said I was leaving ...

_{* According to CSI: Crime Scene Investigation}

The fact that these things don't have complete explanations yet does not mean that you cannot reason about them. For 300 years, gravity had no explanation about its nature. That didn't stop Newton from forming a theory with very successful applications that, in absence of large speeds or large masses, is equivalent to General Relativity.

Umm, CMB is light. It's entirely composed of photons.

..... I'm conpuzzled now.

Okay, so on what basis did the scientists predict what the CMB would look like before they found it?

One is a definition. The other is referring to a scientific theory.

Wikipedia to the rescue!

Can we reason about it or can't we? Word games ftl; you're better than that.

.... well that was disappointly underwhelming. I mean, it's fine and all as studies and theory and that go, but the predictions for the temperature/radiation fluctuated wildly, and it still doesn't give reasons for the most recent prediction before COBE (the only one that matched). From the way it's flaunted like a huge triumph of science I guess I expected more. Thanks for the link anyway, though.

Indeed.

What I am trying to say is that, the fact that we don't know exactly were particles are and what they are doing, unless required, seems a lot like not rendering surfaces in 3d games until they are required to be visible. It's like the universe saves computational resources, which is a hint towards the notion that the universe is some sort of simulation.

From a philosophical point of view, the universe need not have that behavior. Why should there be a collapse of the wave function? the universe could have operated the same way as now if particles were like bullets, i.e. all their attributes (momentum, spin etc) could be measured precisely at the same time. Why particles are waves until observed?

There are still many questions unanswered, but to get back to the original topic, for me, the fact that people can say the Sun revolves around Earth means that modern society has failed in very fundamental tasks.

The universe would be a very different place without QM. There are loads of phenomenon which are only made possible by QM. It is possible to imagine some other universe that didn't follow QM, but it would just be different from ours. I can also imagine a universe which has no gravity, or no quarks.. they're just different.
Actually, one of the first times "quantum mechanics" came into science was when people were trying to describe the light radiated by hot objects. The model at the time had a big problem in that it predicted that basically anything would radiate an infinite amount of energy in the form of ultraviolet light. Max Planck got around this problem by postulating that the radiated light had to come out in discrete chunks.. Quantum mechanics saved the day; and that wasn't the only time. Here's another quick example: an atom consists of a small nucleus with a bunch of electrons zipping around it. Normal electrodynamics would suggest that the electrons should (very quickly) lose energy and spiral into the nucleus, but they never do. Niels Bohr helped fix up this problem by just assuming that the energy levels of an atom must be quantised. My point is that the universe without QM would need to change a bunch of other stuff as well or it just wouldn't work.

Since no one payed attention to me last time I'll say it again: the sun does revolve around the earth. (although it's pretty clear that the intended answer in the game show was the moon) -edit- I wasn't the first to say that.