If so, how? Im just wondering in relation to newtons laws of motion. Such as, an object will remain in its state of motion w/o an external force. Well, is it possible for that to be exactly simulated? Is there a place in the universe where I can throw a ball and it will literally have 0 external forces acting on it?
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Technically it is not possible because gravitational forces (as well as strong, weak, and electromagnetic) can act over an infinite distance. However, at some point the force is so close to zero it makes no practical difference.
Also it is possible to balance out gravitational forces. For example, there is a point between the earth and the moon, where the force of gravity from the moon is equal to the force of gravity from the earth.
Orbiting objects are not truly experiencing zero net forces as it might seem. They do have a centripetal force acting on them (in the case of orbiting a planet this force is gravity). For example, say I am on a space shuttle and am orbiting at exactly the right velocity for a circular orbit and I throw a ball. The ball will go forward and I will recoil. However, the ball is now going faster than the optimum orbital velocity, and will rise some, and I am going slower than the optimum velocity and will fall some.
Also it is possible to balance out gravitational forces. For example, there is a point between the earth and the moon, where the force of gravity from the moon is equal to the force of gravity from the earth.
Orbiting objects are not truly experiencing zero net forces as it might seem. They do have a centripetal force acting on them (in the case of orbiting a planet this force is gravity). For example, say I am on a space shuttle and am orbiting at exactly the right velocity for a circular orbit and I throw a ball. The ball will go forward and I will recoil. However, the ball is now going faster than the optimum orbital velocity, and will rise some, and I am going slower than the optimum velocity and will fall some.
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It may be interesting to consider that we consider the universe to be comprised, broadly, of mass spread out in a uniform distribution. That means that, on average, the mass in any direction would equal the mass in any other direction, and even the force of gravity will be equal. So in this 'general' sense, the gravitational forces are balanced everywhere.
Looking more closely, we know that this distribution is rather lumpy, with stars and galaxies, galaxy groups and galaxy clusters all providing 'graininess' at different scales.
But if the concept of uniformity is to have any meaning, then we have to assume that there are indeed places - surfaces - where the net gravitational force is indeed zero. The other three forces do not really work over large distances, and so can be discounted, but even if you wanted to be very theoretical about it, they too would yield a zero average in a universe with a smooth distribution of mass.
Looking more closely, we know that this distribution is rather lumpy, with stars and galaxies, galaxy groups and galaxy clusters all providing 'graininess' at different scales.
But if the concept of uniformity is to have any meaning, then we have to assume that there are indeed places - surfaces - where the net gravitational force is indeed zero. The other three forces do not really work over large distances, and so can be discounted, but even if you wanted to be very theoretical about it, they too would yield a zero average in a universe with a smooth distribution of mass.