National Public Radio | 2014 Nov 03
Scientist working to create the perfect atomic clock have a fundamental problem:
right now, on the ceiling, time is passing just a little bit faster than it is on the floor.
Scientist working to create the perfect atomic clock have a fundamental problem:
right now, on the ceiling, time is passing just a little bit faster than it is on the floor.
I'm usually pretty boggle-proof, but that has boggled me...bystander wrote:New Clock May End Time As We Know It
National Public Radio | 2014 Nov 03Scientist working to create the perfect atomic clock have a fundamental problem:
right now, on the ceiling, time is passing just a little bit faster than it is on the floor.
The ceiling is slightly further from the centre of the Earth, than the floor. So, as the Earth spins on its axis, the ceiling moves slightly faster than the floor (except at the poles). According to Einstein, this would cause a slight time dilation between ceiling and floor. Solution: only make one clock.MargaritaMc wrote:I'm usually pretty boggle-proof, but that has boggled me...bystander wrote:New Clock May End Time As We Know It
National Public Radio | 2014 Nov 03Scientist working to create the perfect atomic clock have a fundamental problem:
right now, on the ceiling, time is passing just a little bit faster than it is on the floor.
M
I think this effect is small compared with the fact that the clock on the floor is deeper in Earth's gravity well than the one on the wall.Nitpicker wrote:The ceiling is slightly further from the centre of the Earth, than the floor. So, as the Earth spins on its axis, the ceiling moves slightly faster than the floor (except at the poles). According to Einstein, this would cause a slight time dilation between ceiling and floor. Solution: only make one clock.
Gah! I never did get general relativity that well. (And only a tenuous grasp on special relativity.) Imagining gravity equal for a moment and with a clock on the floor and on the ceiling, a floor-dweller would think the ceiling clock was moving slower and a ceiling dweller would think the floor clock was moving slower. (I think.)Chris Peterson wrote:I think this effect is small compared with the fact that the clock on the floor is deeper in Earth's gravity well than the one on the wall.Nitpicker wrote:The ceiling is slightly further from the centre of the Earth, than the floor. So, as the Earth spins on its axis, the ceiling moves slightly faster than the floor (except at the poles). According to Einstein, this would cause a slight time dilation between ceiling and floor. Solution: only make one clock.
Yes. In fact the special-relativistic analogy using velocities doesn't apply here because the clocks are not moving with respect to each other. Interestingly, when considering relative motion, clocks in orbit run slower that clocks on the ground whereas when considering a gravity well, clocks in obit run faster in orbit. A clock located at an orbit of ~1.5 REarth will not loose nor gain time (time dilation = 0) wrt a clock on the ground.Chris Peterson wrote:I think this effect is small compared with the fact that the clock on the floor is deeper in Earth's gravity well than the one on the wall.Nitpicker wrote:The ceiling is slightly further from the centre of the Earth, than the floor. So, as the Earth spins on its axis, the ceiling moves slightly faster than the floor (except at the poles). According to Einstein, this would cause a slight time dilation between ceiling and floor. Solution: only make one clock.
Thank you, Ann; that was kind of youAnn wrote:Good to see you here, alter-ego! Long time no see.
You made a mindboggling point, too!
Ann
So by the end of the day our feet are younger than pur heads...must be the reason for lying down to sleep with elevated feet so that the aging process can balance out overnightBeyond wrote:Decrease your aging by twice the amount. Lay on the basement floor.
"Viewed another way" ...mmmm, I failed to follow through here. Wrt Earth's center, the two clocks do have different velocities, even though wrt each other they don't. The delta velocity, Δv, = ωe x Δh (angular velocity x height above surface). I think we can use special relativity for this case to get a reasonable estimate for the general relativity component of time dilation.alter-ego wrote:Viewed another way, if we put a clock at Earth's center and compare that clock to the floor and ceiling clocks on the surface, time dilation due to motion is the same for the floor and ceiling clock, so their times don't drift due to motion. In this view, the only dilation component between the surface clocks is due to their radial positions in the gravity well, i.e. the height difference between the floor and ceiling.