Force is an attribute of matter, not space. Therefore, a single point particle can never move in a curved path in a universe devoid of any other particles.
So how do you explain the Casimir effect? 'Space' seems to be exerting a force ... In the real world, there is always more than 1 particle in the universe - hence my comment that nothing in nature travels in a straight line.
Even if we drop a weight off a cliff - in the time that the weight is in the air, the earth is rotating under it - and traveling in a linear direction to - at significant velocity. For sake of simplication, we would describe this as a straight line downwards - but in reality that has to be a gross oversimplication.
The linear momentum wouldn't manfest in a relative sense, because both the weight and the cliff would have the same linear momentum, so that doesn't change for either while the weight is in the air. But the earth's rotation would always be a small variable. So free-falling objects on earth can't travel in a perfectly straight line.
ovyyus wrote:
In the case of the spinning object, when parts of that object are spinning relative to other parts of the same spinning object then relative motion is what determines the magnitude of CF (inertia). Therefore, how does the concept of an "absolute space" have any bearing on inertia?
What Jim is saying in other words is that the frame of reference is absolute space.
Suppose the universe were spinning around the object. The relative motion would be the same but without the CF within the part. We know empirically that this does not happen, therefore there is a connection somehow with absolute space. Somehow the universe is one piece. In reference to quantum physics space and time do not seem to be what they appear to be to us.
The linear momentum wouldn't manfest in a relative sense, because both the weight and the cliff would have the same linear momentum, so that doesn't change for either while the weight is in the air. But the earth's rotation would always be a small variable. So free-falling objects on earth can't travel in a perfectly straight line
Well put Greendoor... but it is linear to earth's center. Also interesting is if you put a point on a sphere then rotate it, then also give it some movement in a sraight line while graphing the point at various speeds.
Suppose the universe were spinning around the object. The relative motion would be the same but without the CF within the part. We know empirically that this does not happen, therefore there is a connection somehow with absolute space. Somehow the universe is one piece. In reference to quantum physics space and time do not seem to be what they appear to be to us.
Vic you can't compare relative motion with your example. Relative motion compares mass as a whole or a point particle. The spinning masses central point is the issue when comparing the whole mass to other objects of the universe. To say by using the framework of relativity by shifting observation so it looks like the universe spins around the object, and noting cf in the object doesn't die, does not prove there must be a connection with space, it proves there is a force from a second mass acting on the first mass causing it to travel in an arc, or it proves the mass is spinning from its center of balance ( and a mass is made from many constituent parts ).
Occam's razor.
meChANical Man.
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"All things move according to the whims of the great magnet"; Hunter S. Thompson.
The question is: Spinning in relation to what? An object cannot spin in relation to itself. It would always appear to be stationary in relation to itself. It must therefore spin in relation to the universe.
I sort of view it this way - there must be a geographical center of space - kinda like the celestial center of our galaxy i.e. a point [0,0,0] in our galaxy that appears to remain stationary as the stars rotate around that point [very near the four pointers [the southern cross] in the southern hemisphere ??].
But even our celestial center of our galaxy is within a cluster of galaxies [with their own geographical centers] & those galaxies & clusters are themselves rotating & moving apart - if we were able to define the volume boundaries of the complete universe we could calculate the geographical center of the universe [the real 0,0,0 co-ordinate] - but would this universe geographical center position be the same if we factored in the density of the universe i.e. it appears at a gross scale to be relatively uniform & average but in fact it is quite lumpy & irregular - that means that the gravitational center [momentum center - the hypothetical center of the big bang] of the universe may not be the same place as the geographic center.
Some particle at the gravitational center of the universe would experience equal forces acting on it from all sides & would be stationary in an absolute sense [with everything else moving away from it] - the point is that absolutely every other particle in the universe is having some gravitational force acting on it causing it to bend or curve its trajectory so everything has some Cp forces acting on it [except for a hypothetical particle at the gravitational center of the universe which is exempt because all forces acting on it are of equal magnitude in all directions].
So no one nor anything can escape Cp forces & even a local straight line is curved on a larger scale, so everything can experience Cp forces & therefore know it has inertia [relative to the gravitational center of the universe] provided the measuring scale is large enough & the measuring instruments sensitive enough - JMO's.
The question is: Spinning in relation to what? An object cannot spin in relation to itself. It would always appear to be stationary in relation to itself. It must therefore spin in relation to the universe.
Vic respectfully we've already talked about that in all those past posts. The relationship of a spinning mass is to ( it's constituent parts and, ) it's central pivot point, the place where velocity can be reduced to zero. Or in the case of an object traveling in an arc the relationship is to a secondary mass causing the first to travel in the arc. The example you gave actually seems backwards to me, for if you were to put the observation point on the spinning mass so the universe seemed to spin around the mass and the CF in the mass then suddenly disappeared THEN you would have a valid and profound argument for saying there is a connection to the mass and space. But that doesn't happen in reality so the conclusion seems to be the value of separateness between the mass and space is valid. I'm not saying there's no somethingness to space either; just not in the way it is being put forth. And nothingness deserves its due.
meChANical Man.
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"All things move according to the whims of the great magnet"; Hunter S. Thompson.
