Would it be possible to "block" the effects of gravity.

[FREEFALL1984]

By this of course I mean either; create a material which shields an item from the effects of gravity, or create a counter field to negate the effects of gravity. Of course I am no physicist so for me this is purely speculation, but is it possible, obviously we don't have the technology now but in the distant future will this be one of the things to change the world?

[Ravenchant]

Oh, it's easy enough to do: just put a massive enough object to the opposite side of your item so the forces mostly cancel out... that the object would need to be the size of a small moon/made of neutron star matter should be a minor obstacle.

[Nibb31]

http://en.wikipedia.org/wiki/Gravitational_shielding

[lajoswinkler]

Oh, it's easy enough to do: just put a massive enough object to the opposite side of your item so the forces mostly cancel out... that the object would need to be the size of a small moon/made of neutron star matter should be a minor obstacle.

Also you need to ensure the two objects don't collide, so place some struts in between.

[Skyler4856]

The object will still experience it's own gravity, and that of the material's.

[Dispatcher]

I'm reminded of the concept of gravity waves. If we can use an analogy of water waves (particularly ocean waves), its very difficult to absolutely overcome such waves. However, there might be no reason why we could not navigate gravity waves, as the analogy allows us to do so with water. However, to do so with gravity remains a mystery to me.

[Sillychris]

If you had some method to impart negative mass on an object... you could give it half negative mass and half positive mass. Assuming gravity acts repulsively on negative mass, the two should cancel out and give a net effect of zero.

How to achieve negative mass? That's for the engineers. Shouldn't be too long.

[Seret]

How to achieve negative mass? That's for the engineers. Shouldn't be too long.

It's hard to tell if you're being sarcastic here or not. This is one is firmly in the realm of speculative physics. Engineers work with all the stuff physicists got bored with decades ago.

[Sillychris]

Haha, I was being a little sarcastic. It's a common joke the theoreticians like to toss around "Oh, that's just an engineering problem"

[Winter Man]

I'm reminded of the concept of gravity waves. If we can use an analogy of water waves (particularly ocean waves), its very difficult to absolutely overcome such waves. However, there might be no reason why we could not navigate gravity waves, as the analogy allows us to do so with water. However, to do so with gravity remains a mystery to me.

Why, with a gravity keel of course!

[Idobox]

I'm reminded of the concept of gravity waves. If we can use an analogy of water waves (particularly ocean waves), its very difficult to absolutely overcome such waves. However, there might be no reason why we could not navigate gravity waves, as the analogy allows us to do so with water. However, to do so with gravity remains a mystery to me.

Gravity waves are a real thing, but they don't have anything to do with the form of gravity we are used to, which would be closer to the ocean on which you find the waves.

So how do you protect yourself from getting flooded by the ocean? you build a dyke around the area you want to protect. It works very well for electro-magnetism and is called a Faraday cage (you need specific material to stop constant magnetic fields though).

Now, you just need to find something that stops gravity (hint, we have no idea what could do that), and make a bubble out of it. Stuff inside the bubble would not feel gravity, but the bubble itself would.

[Winter Man]

Now, you just need to find something that stops gravity (hint, we have no idea what could do that)

An infinitely dense shell around you should do it.

Edited March 25, 2014 by Winter Man

[Idobox]

An infinitely dense shell around you should do it.

I'm not even sure it would. At a distance from the shell, you would just see a heavy object.

[Skyler4856]

I'm reminded of the concept of gravity waves. If we can use an analogy of water waves (particularly ocean waves), its very difficult to absolutely overcome such waves. However, there might be no reason why we could not navigate gravity waves, as the analogy allows us to do so with water. However, to do so with gravity remains a mystery to me.

That kind of navigation would be called an orbital transfer

[Kerbin Dallas Multipass]

What about dark energy?

Does it counter gravity or just make space expand? Do we know?

[K^2]

What about dark energy?

Does it counter gravity or just make space expand? Do we know?

We sort of know. Dark Energy contributes to the pressure terms in the stress energy tensor, which is distinct from energy term, which is the source of gravity in most contexts. So it's not going to "block" or "cancel" gravity in general. But it might be close enough for some specific purposes.