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astromark
2007-Aug-28, 07:14 AM
Only a photon and, maybe some other sub atomic particles can actually travel at C. I except this as mostly true.
The amount of energy required to move any larger particle is off the scale. Can not be done. Reluctantly I except this as fact.
Is C. the highest velocity we know of?

No. I have not placed this in the questions section as that should be reserved for scientific and astronomy questions... I want to go off that track a little and inquire if there COULD be a velocity faster. 100 times that of C. or even greater. I wish to call this velocity the speed of quick.
In other threads we have talked of the speed of gravity and reasonable assumption is that it is also C. The idea of instantaneous sort of got lost in the logic of it all. Not to confuse this idea with the expansion rate of the universe. Which I gather could exceed that of C. Which raises another question... If the expansion rate exceeds that of C then what is moving faster than C. and, what is propelling it?

and if you think this should be a question; put it there.

yuzuha
2007-Aug-28, 08:50 AM
C is asymtotic only for physical objects and information. I.e. the phase velocity of microwaves in a wave guide can exceed c though the photons themselves are moving at c or less (velocity of c in some medium other than a vacuum) see: http://en.wikipedia.org/wiki/Phase_velocity

Then there is the idea of tachyons, which can never go slower than the speed of light http://en.wikipedia.org/wiki/Tachyon

Say the speed limit is 10 miles an hour an you are a photon jogging along a rubber road at 10 miles an hour. You want to jog to a place a mile down the road so it should take you 1/10 hour to get there. Now, lets say something is stretching that road between you and that point by 1/2 mile in an hour. so that at the end of an hour that place is 1.5 miles from where you are now. No sweat, you can go 20 times faster than that even under the worst conditions you can get there in 3/20 of an hour.
Now, suppose that the road is 1000 miles long and each mile stretches 1/2 mile in an hour. at the end of an hour, the entire road will be 1,500 miles long, so the entire road is expanding 50 times faster than you can run.

And, at some distance d from your current position, there will be a point where you can eventually reach any point closer than d, but no matter how long you jog, you will never be able to reach any point beyond d since the distance to those points will have expanded beyond your reach in the time it takes you to get to d. There will be another distance horizon for you if you plan on making a round trip. Anyway that is an oversimplification, but somewhat analogous to light horizons and cosmological expansion http://en.wikipedia.org/wiki/Observable_universe