/sci/ - Science & Math

Sorry to annoy you, but I'd really wanna know. Can I do anything in return?

The idea is that the difference in gravitational field between the lower and higher bars will have an effect on the relative time dilation between them, causing one set of clocks to move more slowly than the other.

http://en.wikipedia.org/wiki/Time_dilation#Experimental_confirmation
>In 2010 gravitational time dilation was measured at the Earth's surface with a height difference of only one meter, using optical atomic clocks.[16]

What the fuck is going on?

>>3543472
>wtf
time dilation in an accelerating frame, as explained by Einstein, also,
atomic clocks are pretty damn accurate, considering that they cost about a million bucks a piece.

basically, PROVEN SCIENCE

>>3543469
Nice idea, but that can't be it - if our school owns one of these things, they have to be at least 20 years old. Also, the distance was more like 10 to 20 centimeters.

>>3543497
Are they really clocks? As in, wind-up spring clocks?

>>3543500
I.. actually, I don't know. They were clocks, as in "they had two hands", but I son't know wehter or not they actually measure time just like this, or if they have some other purpose - whichever that might be.

>>3543500
Atomic clocks, probably cesium beam, considered to be very accurate devices, see: http://en.wikipedia.org/wiki/Atomic_clock

no "hands"; LED readouts

>>3543545
True.

We're trying to help OP figure out what his professor's mystery device is, though.

In case it helps, additionally to the two crossbars I already painted, there was a third one with three more clocks lying on the floor beneath it.

>>3543563
There weren't any pendulums, were there?

Even if there weren't, there were a lot of mechanisms for trying to accurately measure time on ships, as this was the only way to determine your longitude accurately. Though that was a lot longer than 20 years ago.

>>3541902
I don't know the name of the experiment, but what you teacher is pointing to is an illustration of the time dilation in a gravitational field. As >>3543465 pointed out.
The upper clocks will show a time1 and the lower clocks time2, the difference being accounted for by the increase in acceleration due to being closer to the center of the mass of the Earth.

Previously, this was not possible to demonstrate due to the imprecision of mechanical clocks. Now however, with extremely accurate atomic clocks, this is easy (albeit expensive) to demonstrate.

A variation on this method involved aircraft carrying 4 cesium clocks flying east - and westward simultaneously and comparing the results - Hafele-Keating Experiment 1971.

Aw, too bad I didn't find the information I need. Still, thanks a whole lot, you guys! You rock!

>>3543667
>>3543469
>>3543465
>mfw despite this clear experimental verification, there are people who still deny relativity because they can't understand it

>>3543754
Gravitational Time Shifts

For small changes in gravitational field associated with changes in altitude above the earth, the approximate time dilation expression see pic

if a comparison is made between a clock on the Earth's surface (TE) and one at height h above the surface (T). Hafele and Keating predicted a time difference of 144 ns on an eastward flight around the world for which the flight time was 41.2 hours. This corresponds to an average height of 8900 m, a reasonable flight altitude for a commercial airline. The time shift is positive (aging faster) for both eastward and westward flights. The predicted value of 179 ns for the westward flight of 48.6 hours duration corresponds to an average altitude of about 9400 meters.