Is it possible that the gravity that keeps our feet planted on the Earth is..

That's fine. Let's still look at the idea that nothing actually curves, but moves in a straight line back and forth because of gravity. Anything wrong with that idea?

 

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The clip is worth watching. I love the begining of that scene where sir whoeverthehell releases a pigeon tied to a coconut...

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Huh? What do you mean, "but moves in a straight line back and forth because of gravity"?

 

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I don't know man. I still want to actually trace the paths of the planets through space.

I just got home from work. Time to veg out and watch some TV

 

The primary thing wrong with it is that it is disconnected from reality. Things do demonstrate curved trajectories due (among other things) to gravity.

It would be akin to saying "I have a theory that all humans die at age 10." The primary problem with that theory would be that it is disproved by simple observation; reality does not support it.

 

The scientist who got burnt was Giordano Bruno, quite some time before Galileo. I think he suggested that the Earth rotates on its axis and that our Sun is just one of many stars.

Ultimately he wasn't burnt for science, but for his different religious beliefs. He didn't believe in Catholicism and he even suggested the existence of aliens. He was ratted out by a former student when their relationship went sour. And most importantly, he refused to recant.

 

@jiveabillion, I know what your problem is. You're an Aristotelian! Please be more "up-to-date". Like up to Galileo.

 

I know there is nothing wrong with being wrong, I just don't see how I can get from one side of the Earth to the opposite side without something pushing against me the whole time. I can easily visualize it in my mind. Maybe it is wrong, but it still makes sense to me and I haven't learned anything yet that contradicts what I am imagining.


Why does the circular motion negate momentum in opposite directions? What I mean is, after the surface of the Earth pushed me around to point D, why don't I still have any resistance to being pushed away from that direction when I get to point A?

 

Those curved trajectories could very well only be curved relative to the observer.

 

Nope. They are in fact curved. As an example, a low earth orbit.

 

When I am in a car, the car and myself are moving in the same direction in a straight line. The Earth is not moving in a straight line, so it has to be pushing me in order to get me to go where it is going.

 

What are you saying?

 

Illustrate the trajectories of the low earth orbit satellite and the Earth relative to the center of the whatever the galaxy orbits. Is it still curved?

 

Have you ever thought that maybe...jut maybe, the Sun's gravity is pulling on you too?

 

I'm saying something that I can't easily get through to anybody on here. I'm basically thinking of the way the Earth would interact with an object on its surface if it had no gravity. I'm apparently thinking of it completely wrong, but I don't see why it is wrong because nothing I have learned or anyone has told me has explained why I am wrong. I can't tell if it is because I can't explain myself properly or if you guys don't understand me.


It basically has to do with the Earth, circular motion, inertia, and momentum. I don't see how if I am on one side of the Earth, my body's inertia doesn't cause any resistance to being moved to the other side. Apparently the circular motion negates all of that, but I don't see how it could.

 

The sun's gravity would be pulling equally on the Earth beneath me. We would fall at the same speed towards the Sun according to Newton's law.

 

Yes.

 

You can't just say "Yes". Where is your illustration?

 

I will give you a thought experiment.

Consider two satellites - one orbiting in a normal orbit, one in a retrograde orbit. (In other words, one orbiting east to west, one orbiting west to east.) In reference to the Earth they make a circle. In reference to the Sun they describe a spiral as the Earth moves. With reference to the center of the Galaxy they describe a spiral within a spiral - one spiral from the orbit of the Earth, one spiral from the motion of the Sun around galactic center,

Now, if you decide to choose a reference frame that is moving, and curving, exactly the same as one of the satellites, you could claim that satellite is not moving with respect to that reference frame. If you then choose a second reference frame that is identical to the first one, but moving in some direction, then you could claim the satellite was going in a straight line. That is the only way you could claim it was going in a straight line for any time at all. There are two problems with this approach:

1) It will only go in a straight line for a short time; it would then start to curve away as it began to diverge from the second reference frame.

2) At that point, in either of those reference frames, there is no way to make the other satellite go in a straight line.

 

Nobody wants to illustrate anything.