What if we could control Gravity?

[betazed]

So here is another science thread.

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It is intriguing that of the four forces in nature we can easily control only one of them, the electromagnetic force. Much of our impressive technology originates from this single achievement of the human mind - the control of the electromagnetic force. What if we could control another force and what if that force was Gravity?

But before I go into that let me answer another question. Why Gravity (and not the other two forces)?

Well, there are three reasons that I can think of (and surely you can come up with more).

(a) Gravity is the only other force that is propagated by a massless particle and hence has an infinite range.

(b) Gravity seems to be the least manipulatable force.

(c) The applications of this force can be truly profound. To see how profound just read on.


Motion

All vehicles that mankind has developed for transportation i.e. to go from here to there, from the beginning of mankind to today (and the forseeable future) depends on Newton's third law. Think about it a little. Every vehicle in every medium, land, water, air and space, from the bullock cart, to the airplane to the car to the submarine to the rocket uses Newton's law. Every vehicle moves by pushing against something.

Yet, the majority of the motions in Universe do not depend on Newton's third law. The majority of motions in the universe depends on gravity.

Could we use gravity to move arbitrarily? Of course we can, if we could control it. Imagine you want to go from one end of the room to another. So you alter the gravity between you and the walls at the opposite ends of the room. The gravity between the distant wall and you is increased and the gravity between the near wall is increased. Presto you move towards the distant wall. Just switch the gravities to decelerate and stop. Easy isn't it.


Start thinking on these lines and you will see that we do not need Newton's third law in any motion. You can have all kinds of moving vechicles including flying saucers.

Invisibility

Gravity is just basically the bending of space time right? And if we could bend it arbitrarily then we could pinch out parts of it right? {Just like twisting a ballon to make two balls out of it - then the surface of one ballon is not connected to the surface of the other. All geodesics on one surface stays strictly on that surface }

Use that to pinch the space around you and you are invisible. Now wouldn't that be fun? of course once you are invisible and inside the pinched space the rest of the world is also invisible to you. But hey, imagine if we could do that to all the garbade we see piling up everywhere.



Storage

Talking of garbage isn't it a mess how it takes up so much of space. I hear that some prime space in Staten Island will never be used because it is being used to dump garbage from Manhattan.

With gravity control there is no such problem. We could enclose an arbitrary amount of space within a finite surface area. We can dump all the garbage of a city into a small sphere the size of a standard trash can.

By the way this will also be a novel solution for carry on baggage problem for airlines.


Weapons

Imagine facing a hugely numerically superior force and you are powered by only one weapon that controls gravity. No problemo! You just zap the space around you (or better still around them) and you are pinched out from their space. Now you can go about doing your own business.


Tractor beams

yes those fancy beams of star trek. It is basically gravity control right? You make the attaraction between you and that object you want to hold on to greater than whatever the motive force is that wants to increase the distance between you, and presto you have a tractor beam!


I could dream on and on.

Could you think of some more? Do you think we will be able to control gravity like this someday? Do you think all this will be possible someday?

 

[the mormegil]

If we could control gravity it would be undoubtably useful, but I doubt we can. We don't actually control electromagnetic forces, we just manipulate them to our needs.

Gravity is considered the weakest force btw.

 

[stormbind]

If we could control gravity, some utter morons would try using it as a weapon to dissipate their enemies (particles would push apart seperate) and then there would be the world-against gravity power; trying to prevent mankind from turning earth into a cloud of dust.

Remember, gravity applies to every single grain of dust - not just big chunks of steel

 

[betazed]

@the mormegil: When I meant control I meant manipulation only. After all we cannot manipulate gravity like we can manipulate electromagnetism.

While the weakness of gravity has something to do with why we cannot manipulate it so easily, if we could manipulate it this weakness would be immaterial.

@Stormbind: While we can argue whether we can control gravity I doubt we will ever be able to alter the sign of gravity to make particles push each other instead of pull each other. Remember we have not been able to change the sign of electromagnetism either. To change the sign we will have to change the laws of physics.

In other words we will have to be omnipotent like Q!

 

[stormbind]

Humn, if you can pull up sheets of steel using gravity then you can certainly pull up clouds of dust and wreck the world using gravity

 

[the mormegil]

You could still easily kill people by using normal push together gravity. You would just crush them.

To be honest I don't see how we can manipulate gravity. First, we need to understand what gravity really is and how it works. The only way I can think of doing it now is increasing the mass of something, but that would just be stupid because, the wall for example, would become so heavy it would sink through the earth's crust.

 

[Bozo Erectus]

Since gravity is a byproduct of mass I dont see how it could ever be harnessed without being able to change the density of mass at will.

 

[betazed]

Originally posted by Dumb pothead
Since gravity is a byproduct of mass I dont see how it could ever be harnessed without being able to change the density of mass at will.

Well, not quite.

Gravity waves (which is basically a perturbation in the spacetime metric) change the distance between two objects without changing any mass anywhere in the local surroundings (just like a tractor beam would do).

Einstein's theory predicts gravity waves but we have not detected them yet. Currently there are many experiments running to detect this. The most famous is LIGO.

Known phenomenon that should generate detectable gravity waves are supernova explosions, black hole mergers etc.

What if we could generate gravity waves?

 

[Bozo Erectus]

Do we know exactly why mass warps space? I mean, why mass produces gravity. I doubt that I'll comprehend your reply, but lets give it a shot.

 

[betazed]

Originally posted by Dumb pothead
Do we know exactly why mass warps space? I mean, why mass produces gravity.

No we don't. Einstein's equations just postulate the relationship between mass and gravity mainly because it seems to be a very sensible equation to which you are inexorably led to if you start with the "equivalence priciple" which is just an axiom.

Originally posted by Dumb pothead
doubt that I'll comprehend your reply, but lets give it a shot.

Why don't you comprehend my other replies? Do I talk in gibberish?

Wasn't my current answer simple.

 

[Hakim]

I read something about gravity being related to electromagnetism. If so, I could imagine a situation where some physicists works in a lab creating and manipulating different kinds of electromagnetic fields, when suddenly an item falls to the floor or starts floating in the air. Once such an anomaly is discovered, things will go quickly. I think a reason why so little is known about gravity is that it always behaves.

Maybe a gravity field could be created, where incoming particles veers off just like charged particles in an electromagnetic field. That field could then be used as a shield for satelllites.

Gravity waves could be used in a radar.

 

[betazed]

@Hakim: Yes there were a few claims about that. But they none of those experiments have been duplicated and no credible theory has been proposed.

It would be really nice though if it were true.

 

[Bozo Erectus]

Originally posted by betazed
No we don't. Einstein's equations just postulate the relationship between mass and gravity mainly because it seems to be a very sensible equation to which you are inexorably led to if you start with the "equivalence priciple" which is just an axiom.

Hmmm...so even the origin of observable gravity is something of a mystery. If we cant understand that, seems to me we have precious little chance of generating gravity waves anytime soon.
What do you think of what this crackpot claims about 'element 115'?

http://www.gravitywarpdrive.com/Element_115.htm

Why don't you comprehend my other replies? Do I talk in gibberish?

Wasn't my current answer simple.

Yes I actually understood you I was afraid your reply would look like:
Since Proffesor Dingleschleim clearly demonstrated that A/$88)Z + @(44^^ = $$5%&, and the Wonngalian Metricitals are alligned with Schplamian fields, we've known why mass produces gravity.

 

[Bobo the Ape]

You can have all kinds of moving vechicles including flying saucers.

Maybe for like a landspeeder type vehicle but the common person has enough trouble travelling in two axes. I don't think we need to give grandma a third!

 

[Pirate]

If we could control gravity everything would change. Like you said we could use gravity to move across rooms, but would we still have rooms? I think EVERYTHING would change. Architecture would be 3 dimensional constructs, set up for acessibility in all directions with every surface useable. We also wouldn't need to build towers, but could suspend hives wherever we wanted them. Life and transportation would be organized in networks of free forming nodes, liberated from the bounds of the surface of the earth. We would grow food in the skies and live in a web of clusters on the earth. "On the earth" would be a blurry term, though, since up and down would have no meaning, depth and elevation would be arbitrary terms. We would dig and hover, contorting the surface of the earth to fit our mindblowing designs of 3 dimensional urban form that would stretch through all levels of the atmosphere.

But why stop there? If we could use gravity to change the size and shape of space itself we could all live in our own personal universe, as large as we like but as close as we want to our friends. Our kitchens could be lightyears from our livingrooms, connected by wormholes of our own creation. We could travel with the rapidity of thought and appear to live forever, we could be those seemingly omnipotent beings we so envy.

But before we get to that point, we will probably shred our region of spactime to pieces trying to figure out how to do it. Pity that.

 

[betazed]

@Pirate: You have such a vivid imagination.

Your post reminded me of the ouster swarms and the vision of human civilization (the farcaster portal, the river styx running thru multiple planets light years apart) from the novel "Hyperion".

 

[betazed]

Originally posted by Dumb pothead
What do you think of what this crackpot claims about 'element 115'?
http://www.gravitywarpdrive.com/Element_115.htm

I finally read it. You defined it correctly. Crackpot.

It makes some extraordinary claims (which necessarily requires extraordinary proof) but provides just some conspiracy theories as proofs. What else can I say? Crackpot is the word that comes to mind.

 

[a space oddity]

I think that eventually we come up with a theorectical way of doing it, but involving so much energy that it will be obvious that pushing against other objects is by far the simpler way to do these everyday things. On a grander scale I suppose we'll find a way to use it, in instances where it's the only viable way to achieve the end (ie absence of things to push away - space travel comes to mind ).

 

[Bozo Erectus]

Originally posted by betazed
What else can I say? Crackpot is the word that comes to mind.

I know, but as Pseudoscience Officer, its my duty to bring these things up.

 

[Pirate]

Originally posted by betazed
@Pirate: You have such a vivid imagination.

Your post reminded me of the ouster swarms and the vision of human civilization (the farcaster portal, the river styx running thru multiple planets light years apart) from the novel "Hyperion".

Thanks! Never read the book but it sounds interesting. My ideas are similar to my musings on "what if teleportation were possible (and routine)?" But that is for another thread...

Science needs some vision. But for practicality, I think space oddity is right. We may only use it to bridge the gap between stars.

One final point on the nature of gravity comes from an article I read that attempted to explain accelerating cosmic expansion by inserting gravity into string theory. Apparently the strings responsible for electromagnetic forces can be expressed as open strings (guitar string) with each end anchored in our 3 dimensions. Gravity is closed strings (loops) which aren't tied down to our 3 dimensions (remember, string theory has 11 dimensions) and therefore can leak out of our universe. Control of gravity may mean understanding how to tap extra extended dimensions. How bout them apples!