[time-nuts] Re: Project Great

[Thomas Valerio]

I think that Tom's GREAT adventure is kind of what sealed the deal making
me a time-nut or at least a time-nuts lurker, a lot of this stuff is still
little over my head, but I keep reading.

If anyone is inclined and has the clocks and the kids ( I don't have
either ), there is always Mount Evans and Pikes Peak, although you may
have to leave the clocks behind overnight.  Mount Evans is still on my
bucket list but without clocks and two or three days of time to monitor
them, I don't think I will be doing the Mount Evans edition of GREAT.  For
anyone that is flush enough to afford or can beg, borrow or steal access
to a Microsemi chip scale atomic clock, I think a Mount Evans edition
would be an awesome addition to Tom's original work.

   Thomas Valerio


> For newcomers to time-nuts, Andy is asking about my DIY gravitational
> time dilation experiment(s).
>
>  > What am I missing?
>
> It looks like you used the wrong value (or wrong units) for "h".
>
> The summit of Mt Rainier is 14411 ft (4400 m), but the highest point on
> Mt Rainier that is accessible by road is the Paradise visitors center at
> 5400 ft. Our house is at 1000 ft elevation so the net difference in
> elevation of the clocks was 4400 ft (1340 m).
>
> The clock(s) on the mountain ran fast by gh/c² = 9.8 × 1340 / (3e8)² =
> 1.5e-13. Fast clocks gain time. We stayed for about 42 hours so the net
> time dilation was 42×3600 × gh/c² = 22 ns.
>
> ----
>
> For more information see the Project G.R.E.A.T. 2005 page:
>
> http://leapsecond.com/great2005/
>
> Better yet, these two recent talks from 2018 and 2020 cover all 3 GREAT
> experiments:
>
> <http://web.stanford.edu/group/scpnt/pnt/PNT18/presentation_files/I08-VanBaak-GPS_Flying_Clocks_and_Relativity.pdf>
>
> <http://leapsecond.com/ptti2020/2020-PTTI-tvb-Atomic-Timekeeping-Hobby.pdf>
>
> Lots of time nutty photos in both of those!
>
> /tvb
>
>
> On 11/27/2021 7:33 AM, Andy Talbot wrote:
>> Just been reading your adventures with 3 Cs clocks, a mountain and 3
>> kids,
>> but I can't make the estimate of time dilation work out.
>> You measured ~ 23ns and say it agrees with calculation
>>
>> The equation quoted in a related reference, for "low elevations" is
>> g.h/c²
>> which if you plug in g = 9.81 m/s²  and h = 4300m for Mt Rainer gives
>> an
>> expected value of 4.7 * 10^-16.
>> Over 2 days, 2 * 86400s, that would be 81 ns in total, four times your
>> value
>>
>> What am I missing?
>>
>> Was just speculating what Ben Nevis at a mere 1340m height might offer
>>
>> Andy
>> www.g4jnt.com
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