No need for gravity?

This is a "push" theory of gravity (rather than a "pull" theory), and that has known problems.

I don’t know where else to go with this idea.

Next time try physicsforums.com or physics.stackexchange.com.

You should note that the existence of dark energy is deduced indirectly from motion of celestial bodies under the assumption that the standard general-relativistic theory of gravity holds. Also, and this is a more general point, educated specialists in any field - not only physics - aren't stupid and really know their field. Therefore, if you, as a non-physicist, can come up with a simple theory of gravity that is not believed by the physicists, the theory is almost certainly false - somebody certainly had the same idea long ago and there were reasons to reject it. Keeping this in mind can save you a lot of time and futile effort.

For reasons why your theory is false please follow the link in Mitchell Porter's comment.

Is this consistent with the fact that my father can demonstrate the gravitational attraction between two lead spheres in our basement?

Also, general relativity has consequences that are relevant to GPS satellites.

Anyway, you'd need equations for any of this to be really meaningful. I suspect that, if you tried to model this mathematically, you'd end up with something that basically matches Newtonian gravity.

EDIT: It turns out it doesn't, to the detriment of a theory of this kind.

I'm thinking no one object within a galaxy is emitting more dark energy than it shields its neighbors from. There is some galaxy-to-galaxy shielding, but it is very weak due to the amount of dark energy that can pass right through without hitting anything.

Which would imply that, on net, two galaxies would tend to attract each other, even if only weakly, because they do shield at least somewhat. I don't think this actually gets anywhere, other than simply pasting something akin to Newtonian gravity on top of an all-pervading repulsive force, such as Einstein's cosmological constant - which is what we already have.

Anyway, if it disagrees with Einstein, it's probably wrong, and if it agrees, then who cares?

Many of the refutations offered didn't actually contradict what I had in mind at all. For instance, I could come up with a (wrong) theory vaguely similar to general relativity, and showing how that's wrong =/= showing general relativity is wrong, similarly, the link about La Sage's theory is not some iron-clad refutation of this one.

However, I wasn't exactly confident that it was right; it actually bothered me that I couldn't come up with why I was wrong. I was mostly expecting to find out why my idea was wrong by running it by others who might already know more than me on the subject. I did wind up getting that (gravitational lensing clearly tears it apart). You guys certainly saved me the effort, either way, which freed me up to focus on actual useful efforts. This sort of effect is actually why I posted here before putting in all that work on something I strongly suspected would be a waste of time.

The main reason I'm commenting here again, is because of the total lack of civility of some of the replies. The negative karma score is probably what the post deserves, and I probably shouldn't expect anything else posting so far from my own specializations. However, there is a certain sting that comes with being wrong, and it's not that difficult to avoid adding to it when pointing out someone's errors. Sadly, the best example of being as rude as possible about it is actually the post that included what I was looking for.

Compare the difference between:

Have you considered gravitational lensing, or gravitational time dilation? Your theory seems to be incompatible with these observable and well-documented phenomena.

and:

Good start. I know how tempting it is to talk about crackpot physical theories, believe you me I do, but you've gotta contain yourself. Seriously, you're embarrassing me, and I'm not even you.

Since you failed #37, among others, I'll help you out. Your theory predicts that what we call gravity depends not on mass but on something like solid angle, which is a measure of how big one object appears from another. If we're talkin bout heaven here objects are spherical, so solid angle (and thus your theoretical force) depends only on the size of the object (radius) and distance. Guess what? It turns out that gravity actually depends on something called mass and energy. Newtonian gravity is linear in mass, but your theory is not (you can work out the relationship between proton count and surface area of a nucleus or something along those lines, tee hee). This linearity has been experimentally verified.

Anyway, does your theory have anything to say about this or this? Nope! It turns out gravity isn't as simple as pushing and pulling. Time and energy and fahoosalah are involved too. You might know about these things if you take physics courses.

LessWrong is partly about learning how to be wrong. You're wrong. LessWrong teaches to acknowledge when you don't understand something, to listen to the knowledge of those who do, and to not post silly crackpot theories that don't even. 0/10 will not think about again.

I’m not a physicist and it could be obviously wrong for some reason I’m missing

Good start. I know how tempting it is to talk about crackpot physical theories, believe you me I do, but you've gotta contain yourself. Seriously, you're embarrassing me, and I'm not even you.

Since you failed #37, among others, I'll help you out. Your theory predicts that what we call gravity depends not on mass but on something like solid angle, which is a measure of how big one object appears from another. If we're talkin bout heaven here objects are spherical, so solid angle (and thus your theoretical force) depends only on the size of the object (radius) and distance. Guess what? It turns out that gravity actually depends on something called mass and energy. Newtonian gravity is linear in mass, but your theory is not (you can work out the relationship between proton count and surface area of a nucleus or something along those lines, tee hee). This linearity has been experimentally verified.

Anyway, does your theory have anything to say about this or this? Nope! It turns out gravity isn't as simple as pushing and pulling. Time and energy and fahoosalah are involved too. You might know about these things if you take physics courses.

LessWrong is partly about learning how to be wrong. You're wrong. LessWrong teaches to acknowledge when you don't understand something, to listen to the knowledge of those who do, and to not post silly crackpot theories that don't even. 0/10 will not think about again.