Artificial Gravity

[wfbberzerker]

well once we can make artificial gravity, all we have to do is reverse the polarity, and BAM - antigrav engines.

 

[Intelia]

Originally posted by: Cattlegod
Well the easy way is to have a rotating spaceship where all the stuff you use is on the walls of the spaceship. Other than that, no.

At the present time this is the only method

 

[unipidity]

Microgravity, surely, is defined as the situation in which objects act as though there is no gravitational field present? ie an inertial frame of constant acceleration like an elevator in freefall? If you could 'exclude' the field, then that would not be microgravity, but actually no gravity at all. Which you cant, as far as I know.

As for the source of gravity... mass. The exchange mechanism perhaps not, but I dont see how the source is a matter for debate.

 

[Eeezee]

Artificial gravity? Do you mean generating a force that feels like gravity or do you mean something that can cancel out gravity?

There's angular momentum, megnetism, centrifugal force... yeah, we can generate "artificial gravity" but it's not really gravity. These are just forces that we can tweak and manipulate to make a person feel like they're under the influence of a gravitational force.

For example, someone in freefall in space feels weightlessness, so you could generate some "artificial gravity" by rotating the room that they're in. This will make them feel a downward force kind of like gravity.

 

[CrimsonCutie]

Gravity is accuatlly the weakest of all forces.. as you just pointed out with your reference to magnetic power. A mangetic field suspending something doesn't affect its mass at all.. if it were to change it mass... (ie removeing it to make it lighter resulting in les gavitaional attraction between the object and the major soruce of gavity around it... ie the planet earth) it would have to release alot of eneregy---can we can atomic bomb... because you can't just remove mass. Something suspended in a magentic field has the same mass as befor.. mass is constant... gavity is merely a force of 11-dimensional properties of 2 bodies of mass and their propensitiy to move towards eachother.

The weakness of gravity can also be seen by looking at the universe.... with all the mass all around us... we are still expandings and gaining speed... the "vacumme energy" property of space that seems to be a constant force acting out against matter in it absence. Where as 2 galaxies move fruther apart their attractive force (gravity) lessens the vaccume reuplusive force remains contant... so they speed up moveing faster and faster apart.

 

[grobeg]

Most folks ask about "artificial" gravity when what they mean is "Anti" gravity.
Artificial gravity is the most obvious idea of the spinning space station.
Anti Gravity, would entail ignoring, or using gravity against itself.
When we learn to use gravity, the way Sailors use the currents of the ocean, we will become explorers of the universe.

 

[Gamingphreek]

I am referring to creating a "field" if you will, that imitates gravity.

Additionally, i remember a long time ago, i heard someone say that all objects have gravity. For instance, us humans have gravity, but we are simply too small for it to affect anything. Is this true?

 

[Powermoloch]

There are experiments of using centrifugal force, like carrying a bucket of water and turning it around up and down without spillage.

 

[BitByBit]

What you're referring to is centripetal acceleration and the force requried to produce that acceleration.
An object (such as a bucket of water) swung around in an orbit tends to want to fly off at a tangent, that is, perpendicular to the direction of the force keeping that object in circular motion.
Water will stay inside a bucket turned upside-down as a result of circular motion provided the centripetal acceleration is greater than the acceleration due to gravity.
In other words: v^2 / r > 9.81 ms^-2.

All objects have a gravitational field - not just celestial bodies.
If you want to calculate the attraction in Newtons of two bodies, use the equation:

F = GM{1}M{2} / r^2

Where G (The Gravitational Constant) = 6.67 X 10^-11, M{1} and M{2} = the masses of both objects in Kg, and r = the distance between the centres of mass of both objects.
According to Einstein, the force due to gravity is actually caused by a warping of space/time, such that the geometry of the surrounding space causes two objects within eachother's gravitational field to fall toward eachother by default, so that there energy states become lower.
The degree of warping is actually dependent on the amount of energy involved. Since mass and energy are very roughly the same thing (mass can be thought of as 'condensed energy'), an object of greater mass will cause a greater warping of space, just as an object with greater KE for example will cause the same thing.
My own hunch regarding what happens when an object approaches the speed of light is that because the fabric of the Universe cannot support such large concentrations of energy, the object would eventually disappear and be replaced by a black hole - just as collapsing stars whose rising energy levels warp space to such a degree that the surrounding space tears also get replaced with a black hole.

So, if you want to create a powerful enough artificial gravitational field, then you need energy, and lots of it.

 

[unipidity]

No, then. A gravitationl field is a gravitational field, and you cant fake it. No more than you can with any field. There is no magical source of gravity, and certainly no currently identifiable way of producing a negative gravitationl field.

 

[Particle]

Gravity is energy related to mass. Anything 'mass' will have gravity or a magnetic field associated with it. Big or small. So if you want gravity you have to have mass and visa-versa. Centrifugal force is like planet rotation. By you rotating the bucket directly with your arms you are creating an energy source that is much greater then the bucket in relation to you and the universe so the bucket rotates around you. The sun/planets have gravity and the stronger one makes the smaller planets rotate around them the most. I think the magnetic fields around the planets and the ones relating to each other would be the space time warp talked about.
My question is, if I had another force of gravity how could I use it to repel the gravity holding down a car for example. Is their a known substance with high magnetic fields that can do this or would an electrical charge have to be administered? How safe is it to walk between it?

 

[BitByBit]

Do you even know what you're talking about?

 

[piddlefoot]

a friggin cold superconductor can levitate, a magnet can, we see it all around us in the universe yet we cant actually touch gravity, he whom can harness will take humans to the stars at speeds way beyond light so is it possible ? Gravity has that power we see it in blackholes, but what is it ?
Maybe one day man will learn like electricity, magnetism and gravity , l believe its possible because we can creat it now fact just not the way we would like to.....
Spin something hard enough it creates gravity, artaficial if we created it, but what we need is what you see in star trek.....

 

[Particle]

What about cold fusion? Isn't that as powerful as the sun? How could a spacetime gravity warp be created from something like that? They are currently building a fusion plant in France. Would all of that energy need to be going on at once or does it need to be in mass form like a planet? Although at the core resides more energy.

 

[Stonejaw]

I know it is possible to create anti-matter but in small quantities, if it would be possible to get a larger quantity of antimatter would that matter have antigravity?

 

[Particle]

Also another thing I was interested in was that gravity doesn't seem to harm the human body and organics similar to rotational gravity but rotational gravity isn't as fun.

 

[Matthias99]

Originally posted by: Stonejaw
I know it is possible to create anti-matter but in small quantities, if it would be possible to get a larger quantity of antimatter would that matter have antigravity?

Antimatter experiences (and generates) gravity just like normal matter. Its atoms are made of the same 'stuff' (quarks in different combinations), just put together differently.

 

[Matthias99]

Originally posted by: Particle
Also another thing I was interested in was that gravity doesn't seem to harm the human body and organics similar to rotational gravity but rotational gravity isn't as fun.

High 'natural' gravitational fields would be just as damaging as any other type of extremely high acceleration. The Earth's gravitational pull seems harmless because our bodies are built to withstand 1g of acceleration in the vertical direction all the time. If you were suddenly subjected to a 100g vertical acceleration (no matter what the source), you'd collapse to the ground in a heap.

 

[Soccerman06]

Originally posted by: Matthias99

Originally posted by: Particle
Also another thing I was interested in was that gravity doesn't seem to harm the human body and organics similar to rotational gravity but rotational gravity isn't as fun.

High 'natural' gravitational fields would be just as damaging as any other type of extremely high acceleration. The Earth's gravitational pull seems harmless because our bodies are built to withstand 1g of acceleration in the vertical direction all the time. If you were suddenly subjected to a 100g vertical acceleration (no matter what the source), you'd collapse to the ground in a heap.

Well if Goku could do it, we must be able to do it to... oh wait that was a cartoon.

 

[DrPizza]

For what it's worth, gravitational forces can and have been simulated. However, they are not "gravitational forces."

Minor correction to something (I think) I read above: Someone stated there is no such thing as "centrifugal force." That's fine with me to state that. However, Newton's 3rd law: for every action force, there's an equal and opposite reaction force shows that if a string is exerting a 10 Newton force on an object being swung in a circle (acceleration and force are directed toward the center of the circle) then the object must, of course, be exerting a 10 Newton force on the string in the opposite direction (away from the center.)

When a car goes rapidly goes around a corner, centripetal force is the force of the car (the car door) pushing against me to keep me going around the corner with the car. If the car door opens, I go sailing out, tangent to the curve. However, I am also exerting a force against the door, equal to the force the door is exerting on me.

Look up a nifty device called a "centrifuge." Why do you think they named it that? After all, there's no such force, right? Or, as I have shown above, are particles pushing outward? Again, I have no problem with saying there's no such thing as "centrifugal force." But, there's no denying that forces ALWAYS ALWAYS ALWAYS occur in pairs - equal and opposite in direction.

 

[Xyo II]

Originally posted by: Particle
What about cold fusion? Isn't that as powerful as the sun? How could a spacetime gravity warp be created from something like that? They are currently building a fusion plant in France. Would all of that energy need to be going on at once or does it need to be in mass form like a planet? Although at the core resides more energy.

cold fusion hasn't been replicated in any more experiments except that first one that got all the scientific publicity, has it?

 

[Woodchuck2000]

Originally posted by: Particle
Gravity is energy related to mass. Anything 'mass' will have gravity or a magnetic field associated with it. Big or small. So if you want gravity you have to have mass and visa-versa. Centrifugal force is like planet rotation. By you rotating the bucket directly with your arms you are creating an energy source that is much greater then the bucket in relation to you and the universe so the bucket rotates around you. The sun/planets have gravity and the stronger one makes the smaller planets rotate around them the most. I think the magnetic fields around the planets and the ones relating to each other would be the space time warp talked about.
My question is, if I had another force of gravity how could I use it to repel the gravity holding down a car for example. Is their a known substance with high magnetic fields that can do this or would an electrical charge have to be administered? How safe is it to walk between it?

Seriously, read a physics textbook.

Gravity is not energy. It is a warping of spacetime related to the mass of a body.
Centrifugal force is not like planet rotation.
You do not create an energy source by rotating buckets.
Not all of the planets have magnetic fields.

In answer to your question, you can't. You can use electromagnetic fields to generate a force to lift a car off the ground but that's no different from picking it up using a crane. You can't 'repel' gravity.

I would be safe to walk through such a magnetic field, although your credit cards would disagree.

 

[Woodchuck2000]

Originally posted by: Gamingphreek
Can we achieve artifical gravity yet. And i dont mean strapping magnets to our feet or anything.

Also, being able to and having done are 2 differnt things. Have we ever succesfully accomplished this feat.

-Kevin

If we can agree that gravity is in effect the curvature of spacetime, then if we can find a way to warp spacetime without recourse to large masses the answer is yes.

Imagine a flat, stretched bedsheet as spacetime (give or take a couple of dimensions). Place a brick in the middle and call it the sun. The fabric of spacetime (ooh, pun...) is now curved. If you roll a marble across the bed, it will head for the sun (brick). That is the simplest possible visualisation of how gravity actually works. Scaling it up to higher dimensions isn't easy in terms of visualisation so we'll stick with this one for now.

Imagine for a second that as the marble is rolling slowly towards the sun, you stick a couple of fingers up from underneath the bedsheet. You create a little upwards ripple in spacetime which stops the marble rolling and holds it still. What you've done there is manipulated spacetime to prevent the marble succumbing to the gravitational attraction of the brick.

What we need to do is find a way of sticking a proverbial two fingers into spacetime and adjusting its curvature to counteract gravitational effects. It's theoretically possible but as to how to adjust the curvature in real life? Not a clue.

 

[Howard]

Originally posted by: Cattlegod

Originally posted by: BitByBit
Circular motion is possibly one of the least understood areas of physics.
There is no such thing as 'centrifugal force'. There is, however, centripetal force.
This is the force required to keep an object in circular motion, and is given by the equation:

F = mv^2 / r

Where v^2 / r gives the acceleration toward the centre of the orbit.

What people call centrifugal force is really inertia.

Simply put, when you are rotating in a circle you are under constant acceleration. When you are standing on a planet with gravity, you are under constant acceleration. For all intensive purposes, its effects are exactly the same as gravity.

Intensive purposes? lmaonade

 

[sao123]

Originally posted by: DrPizza
For what it's worth, gravitational forces can and have been simulated. However, they are not "gravitational forces."

Minor correction to something (I think) I read above: Someone stated there is no such thing as "centrifugal force." That's fine with me to state that. However, Newton's 3rd law: for every action force, there's an equal and opposite reaction force shows that if a string is exerting a 10 Newton force on an object being swung in a circle (acceleration and force are directed toward the center of the circle) then the object must, of course, be exerting a 10 Newton force on the string in the opposite direction (away from the center.)

When a car goes rapidly goes around a corner, centripetal force is the force of the car (the car door) pushing against me to keep me going around the corner with the car. If the car door opens, I go sailing out, tangent to the curve. However, I am also exerting a force against the door, equal to the force the door is exerting on me.

Look up a nifty device called a "centrifuge." Why do you think they named it that? After all, there's no such force, right? Or, as I have shown above, are particles pushing outward? Again, I have no problem with saying there's no such thing as "centrifugal force." But, there's no denying that forces ALWAYS ALWAYS ALWAYS occur in pairs - equal and opposite in direction.

The gospel according to DrPizza.
Amen.