Gravity Probe B and Our 4-Dimensional World: Does Time Stand Still?

Descartz2000
Messages
138
Reaction score
1
Do the Gravity Probe B results provided by NASA from 2011 support and lean in favor of a 4-dimensional everyday world? The world you and I live in. Do the results argue for block time?
 
Physics news on Phys.org
Descartz2000 said:
Do the Gravity Probe B results provided by NASA from 2011 support and lean in favor of a 4-dimensional everyday world? The world you and I live in. Do the results argue for block time?
The results are consistent with GR to a rather low level of accuracy. I think that is about all you can say.
 
There's a great anecdote from a Tom Stoppard play:

George: Meeting a friend in a corridor, Wittgenstein said: 'Tell me, why do people always say it was natural for men to assume that the sun went round the Earth rather than that the Earth was rotating?' His friend said, 'Well, obviously, because it just looks as if the sun is going round the earth.' To which the philosopher replied, 'Well, what would it have looked like if it had looked as if the Earth was rotating?'

Descartz2000 said:
Do the Gravity Probe B results provided by NASA from 2011 support and lean in favor of a 4-dimensional everyday world? The world you and I live in.

To make your question meaningful, you'd have to define what you thought the world would be like if it was *not* four-dimensional. Newtonian mechanics can be described in terms of a 4-dimensional world.

Descartz2000 said:
Do the results argue for block time?
The block universe is a philosophical idea, not a testable scientific theory. The block universe picture has been discussed many, many times on PF, e.g., https://www.physicsforums.com/showthread.php?t=643851 .
 
Last edited:
OK, so this has bugged me for a while about the equivalence principle and the black hole information paradox. If black holes "evaporate" via Hawking radiation, then they cannot exist forever. So, from my external perspective, watching the person fall in, they slow down, freeze, and redshift to "nothing," but never cross the event horizon. Does the equivalence principle say my perspective is valid? If it does, is it possible that that person really never crossed the event horizon? The...
In this video I can see a person walking around lines of curvature on a sphere with an arrow strapped to his waist. His task is to keep the arrow pointed in the same direction How does he do this ? Does he use a reference point like the stars? (that only move very slowly) If that is how he keeps the arrow pointing in the same direction, is that equivalent to saying that he orients the arrow wrt the 3d space that the sphere is embedded in? So ,although one refers to intrinsic curvature...
So, to calculate a proper time of a worldline in SR using an inertial frame is quite easy. But I struggled a bit using a "rotating frame metric" and now I'm not sure whether I'll do it right. Couls someone point me in the right direction? "What have you tried?" Well, trying to help truly absolute layppl with some variation of a "Circular Twin Paradox" not using an inertial frame of reference for whatevere reason. I thought it would be a bit of a challenge so I made a derivation or...
Back
Top