hi again!
i know that acceleration or rotation creates artificial gravity. But what i dont know is how does motion in 1 step higher or lower dimension behaves, feels.
e.g you probably have seen videos in the Internet, using the "Flatland"´ers (2D beings) to describe wormholes etc.
well take this flatland, and rotate/accelerate it in 3d dimension, along the axis which does not exist in flatland. obviously the flatlanders wouldnt see any movement, but....could the feel it. i mean...the centripetal force, which for them would seem like unexplainable pull or push.
the same way, what effect would there be on us, if..lets say our 3D world rotates/accelerates along 4th dimension? if 4th dimension exists, then how would we feel the acceleration/centripetal force in our 3D world.
Also...ive a question about the einsteins theory about gravity. he said that space-time is distorted by heavy objects. e.g heavy object creates a concavity in the space time and all objects must follow the curvature of the space-time fabric. well...if you start to think about it, then it wont explain anything. so...objects should follow the curvature of space time. but they dont. and the way its depicted in all the videos/books/pictures, requires the existence of gravity itself too. why should objects in universe(planets) fall into the concavity generated by a more massive object? if objects simply folowed the curvature of the space-time, they wouldnt get "stuck" in these dents in space-time.
What is a 2D being and how can a 3D space rotate around a 4th dimension when any rotation of anything in 3D necessarily would take place in the same 3 dimensions? From the perspective that the 4th dimension is time, which seems most sound to me, 3D space "rotating" along the time axis would imply accelerating and decelerating in time, while going back and forth along the axis. If this was possible, why would it result in any kind of centrifuge-like effect on matter?
I also don't understand how time could ever go backward. Apparently it can go faster or slower depending on gravity or velocity, but it's always moving in the same direction. Time going backward would be like having negative temperature (measured in Kelvin). If there was some way to continue removing energy from matter totally devoid of energy, that matter would have to absorb a proportional amount of energy to its -K temperature to even reach 'absolute' zero, at which point it would begin to thaw.
If time is a function of kinetic energy, then perhaps negative kelvin temperatures would produce negative time. But events that occurred while matter was decelerating through loss of heat would not reverse themselves because zero kelvin was reached and an energy 'deficit' ensued. Instead it would seem that negative K would just increase the amount of energy needed to return the matter to an energy level dynamic enough to allow movement, and therefore time.
How else could time go backward?
froarty
25th September 2009 - 05:09 PM
QUOTE
What is a 2D being and how can a 3D space rotate around a 4th dimension when any rotation of anything in 3D necessarily would take place in the same 3 dimensions? From the perspective that the 4th dimension is time, which seems most sound to me, 3D space "rotating" along the time axis would imply accelerating and decelerating in time, while going back and forth along the axis. If this was possible, why would it result in any kind of centrifuge-like effect on matter?
2D = chalkboard figure
3D doesn't have to rotate if time is a rolled up dimension then just relative motion as time permeates our dimensions it will, as scorpion 9 mentioned, seem to push and pull at us in unexplainable ways that sum to our local definitions of "Up and Down", These summations coincide with a spatial direction at the macro scale but at the atomic scale are actually at right angles to spatial axii. My pet theory is that
the nucleus has a temporal axis offset to the orbital forming a vortex or trunk with a constant volume - when accelerated the volume remains constant but the radius contracts while the trunk get longer - This is sort of what you see in Lorentz contraction that frames with different accelerations appear smaller to each other from a relativistic perspective. Ron Mallet makes an analogy of stirring a coffee cup where we only see the surface but as you stir faster the swirling froth at the center gets smaller and faster while the trunk gets deeper down into the coffee(dimension of time). If this nuclear vortex is related to our perception of time then we would never be able to see the froth getting smaller (like Bohr radius) it would always appear constant in the same way C always seems constant regardless of your acceleration. We would remain blissfully unaware in changes in the rate of time except differentially when comparing to a frame with a different acceleration.
light in the tunnel
25th September 2009 - 06:18 PM
QUOTE (froarty+Sep 25 2009, 05:09 PM)
We would remain blissfully unaware in changes in the rate of time except differentially when comparing to a frame with a different acceleration.
How can the rate of time change without the possibility of measuring it? If all instruments capable of measuring the rate of time are "blissfully unaware" of such changes, then in what sense is the rate of time changing?
This sounds like saying that the rate at which the universe is expanding may be accelerating and decelerating, but there's no way to observe it because everything is expanding relative to everything else in a way that doesn't affect the position of anything vis-a-vis anything else. If this was the case, what basis or reason would you have for speculating that the rate of expansion is changing?
froarty
25th September 2009 - 07:55 PM
QUOTE
How can the rate of time change without the possibility of measuring it? If all instruments capable of measuring the rate of time are "blissfully unaware" of such changes, then in what sense is the rate of time changing?
Good point - you can not measure between frames and internal to the frame we are blisfully unaware. It is only when the watch that was aboard the accelerating spaceship or the still young twin that was wearing it return to more stationary earth that the difference can be measured in time or aging. Even though the rate of time returns to normal for the twins and their watches, the accumulated time dilation is the evidence that remains. The case has been proved by comparison of precise time clocks on earth vs in orbit. high acceleration spatially slows the pasage of time.
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