Project Great
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
On 11/27/21 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
Considering the parking lot is around 200m, carrying the clocks and
power to the top might be moving from a moderate walk to the strenuous
category. One might also want to do this in summertime, so you've got a
few months to plan the expedition.
I wonder what the highest road in the UK is?
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://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
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
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 à 1340 / (3e8)² =
1.5e-13. Fast clocks gain time. We stayed for about 42 hours so the net
time dilation was 42Ã3600 à 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://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
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
send an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
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To unsubscribe, go to and follow the instructions there.
On 11/27/21 12:37 PM, Thomas Valerio wrote:
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
I don't think a CSAC would be good enough.
Tom's experiment was 22 ns out of 42 hours or about 1.45E-13. That's
quite a bit smaller than a CSAC adev over that period.
There's a variety of roads that go to ~12,000 ft in Colorado, about
~10,000 in CA (Tioga Pass isn't closed yet), so you can get about 3x
change, but still you're talking <1E-12.
Mammoth Mtn has a gondola to the top, but it's only 11,000. There may be
a ski resort in CO that's higher.
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://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
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
send an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
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To unsubscribe, go to and follow the instructions there.
Hi
The CSAC is not a cesium in the conventional sense. It is much closer to
a telecom Rb than anything else. There likely are telecom Rb’s that would
do a better job. Would they do a good enough job? …. likely not ….
Bob
On Nov 27, 2021, at 5:11 PM, Lux, Jim jim@luxfamily.com wrote:
On 11/27/21 12:37 PM, Thomas Valerio wrote:
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
I don't think a CSAC would be good enough.
Tom's experiment was 22 ns out of 42 hours or about 1.45E-13. That's quite a bit smaller than a CSAC adev over that period.
There's a variety of roads that go to ~12,000 ft in Colorado, about ~10,000 in CA (Tioga Pass isn't closed yet), so you can get about 3x change, but still you're talking <1E-12.
Mammoth Mtn has a gondola to the top, but it's only 11,000. There may be a ski resort in CO that's higher.
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://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
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
send an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
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To unsubscribe, go to and follow the instructions there.
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To unsubscribe, go to and follow the instructions there.
Hi,
There is an overemphasis on the atom being used, and especially on
cesium as that is what is used for SI definition. However, actual
implementation means actual physical devices, and the physical devices
have a physics package, for which details will be important to the
actual performance. Various atoms have been more or less well adapted to
different types of physical package types. The beam type of device can
be made to have very little perturbation, and cesium was well suited for
that, while rubidium ended up being very well suited for the gas cell
type. The CSAC is really a cesium based gas cell, but the original
benefit of rubidium filtered optical pumping has been replaced with
semiconductor lasers for pumping. Today both cesium and rubidium gas
cells with the same mechanism exists. With gas cell you get wall shift
from atoms banging around the wall, but also gas shift as buffer gas
makes the atoms hit the buffer gas most of the times. With a bit of
selection of gas mixture, these can be made to balance each other.
So, what is the claim to fame for CSAC? It's actually not being cesium,
but for the stability it provides for the small amount of power it
consumes. That's also where it finds actual applications. If you can
afford more power, there is cheaper alternatives available.
Cheers,
Magnus
Den 2021-11-27 kl. 23:28, skrev Bob kb8tq:
Hi
The CSAC is not a cesium in the conventional sense. It is much closer to
a telecom Rb than anything else. There likely are telecom Rb’s that would
do a better job. Would they do a good enough job? …. likely not ….
Bob
On Nov 27, 2021, at 5:11 PM, Lux, Jim jim@luxfamily.com wrote:
On 11/27/21 12:37 PM, Thomas Valerio wrote:
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 ValerioI don't think a CSAC would be good enough.
Tom's experiment was 22 ns out of 42 hours or about 1.45E-13. That's quite a bit smaller than a CSAC adev over that period.
There's a variety of roads that go to ~12,000 ft in Colorado, about ~10,000 in CA (Tioga Pass isn't closed yet), so you can get about 3x change, but still you're talking <1E-12.
Mammoth Mtn has a gondola to the top, but it's only 11,000. There may be a ski resort in CO that's higher.
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://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 calculationThe 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
valueWhat am I missing?
Was just speculating what Ben Nevis at a mere 1340m height might offer
Andy
www.g4jnt.com
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
send an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
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To unsubscribe, go to and follow the instructions there.
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To unsubscribe, go to and follow the instructions there.
On 11/27/21 3:20 PM, Magnus Danielson via time-nuts wrote:
Hi,
There is an overemphasis on the atom being used, and especially on
cesium as that is what is used for SI definition. However, actual
implementation means actual physical devices, and the physical devices
have a physics package, for which details will be important to the
actual performance. Various atoms have been more or less well adapted
to different types of physical package types. The beam type of device
can be made to have very little perturbation, and cesium was well
suited for that, while rubidium ended up being very well suited for
the gas cell type. The CSAC is really a cesium based gas cell, but the
original benefit of rubidium filtered optical pumping has been
replaced with semiconductor lasers for pumping. Today both cesium and
rubidium gas cells with the same mechanism exists. With gas cell you
get wall shift from atoms banging around the wall, but also gas shift
as buffer gas makes the atoms hit the buffer gas most of the times.
With a bit of selection of gas mixture, these can be made to balance
each other.
So, what is the claim to fame for CSAC? It's actually not being
cesium, but for the stability it provides for the small amount of
power it consumes. That's also where it finds actual applications. If
you can afford more power, there is cheaper alternatives available.
Not only is the CSAC low power (~ 100 mW) it's physically small, which
is attractive for some applications (inside a cubesat, for instance).
It used to be price competitive with a Rb, too ($1000-1500, as I recall)
but now they're about $5k. Microsemi also has the NAC (which is more a
conventional Rb, but small)
Parameter NAC1 CSAC
Aging 3E-10/mo 9E-10
1E-9/yr 10E-9
ADEV 2E-11 @ 100sec 2.5E-11
8E-11 @ 10 8E-11
2E-10 @ 1 sec 2.5E-10
phase noise
-86 @ 10 -70
-120 @ 100 -113
-138 @ 1000 -128
-143 @ 10k -135
-148 @ 100k -140
-150 floor
max chg 1E-9 (-20 to 65) 5E-10 (-10 to 35)
pwr 1.2W op 0.12
1.8W warm 0.14
Hi Jim,
Den 2021-11-28 kl. 01:26, skrev Lux, Jim:
Not only is the CSAC low power (~ 100 mW) it's physically small, which
is attractive for some applications (inside a cubesat, for instance).
It used to be price competitive with a Rb, too ($1000-1500, as I
recall) but now they're about $5k. Microsemi also has the NAC (which
is more a conventional Rb, but small)
Parameter NAC1 CSAC
Aging 3E-10/mo 9E-10
1E-9/yr 10E-9
ADEV 2E-11 @ 100sec 2.5E-11
8E-11 @ 10 8E-11
2E-10 @ 1 sec 2.5E-10
phase noise
-86 @ 10 -70
-120 @ 100 -113
-138 @ 1000 -128
-143 @ 10k -135
-148 @ 100k -140
-150 floor
max chg 1E-9 (-20 to 65) 5E-10 (-10 to 35)
pwr 1.2W op 0.12
1.8W warm 0.14
A good comparison.
In addition, for some application weight of the CSAC is also very
attractive.
I'm not to say that CSAC is bad, but rather that one has to understand
that it is a product intended for certain uses, and for those contexts
it is a very interesting option, but outside of those contexts, there
may simply be better suited options. It being "cesium" is not the magic
keyword thought.
Cheers,
Magnus
Hi Thomas,
Good to hear the experiment was contagious for you. If you have
additional questions let me know.
Your suggestion about Mount Evans and Pikes Peak are excellent. You will
enjoy this 2017 paper:
"An Undergraduate Test of Gravitational Time Dilation"
https://arxiv.org/abs/1710.07381
https://arxiv.org/pdf/1710.07381.pdf
As for CSAC, the news is not so good. I've worked with several groups to
explore CSAC for gravitational time dilation experiments. Those clocks
are so cute and small, it's irresistible; but the numbers just don't add
up. Over a day their stability is in the low e-12's vs. a "real" cesium
clock like a 5071A in the low e-14's. So when you are doing a relativity
experiment trying to detect a frequency shift that's on the order of
e-13's you reach for a 5071A instead of a CSAC. The performance is
nearly 100 to 1.
One solution is a taller mountain. The best on the planet is Mauna Kea
(Big Island, Hawaii) where you can literally drive from sea level to the
summit (13,800 ft, 4200 m) in a few hours. The frequency shift up there
is 4.5e-13, which is 40 ns per day. But still, to have even the
slightest chance of success you'd want your clocks to be good to 1e-13
or better. CSAC aren't even close, and probably neither are telecom Rb.
I'm currently involved with another solution -- a HAB (High Altitude
Balloon) CSAC flight. Getting to 100,000 ft altitude is quite common. Up
there, clocks run a whopping 3.3e-12 faster, which is 280 ns/day, or 12
ns/hour. This is a clear case where the amazing low mass and low power
of a CSAC is a critical advantage. However, the numbers still aren't
working out and the logistic and environmental conditions are brutal. I
won't say it's impossible, but it may take years and a huge bag of
tricks before it works or it's proved too impractical.
Jim, I'd be interested in any Cubesat / CSAC results. They don't exactly
land in one piece so the typical round-trip clock comparison method
wouldn't work. A direct frequency comparison might. In that case the
drift and re-trace specs of a CSAC are probably more important than the
stability.
/tvb
On 11/27/2021 12:37 PM, Thomas Valerio wrote:
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://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
time-nuts mailing list --time-nuts@lists.febo.com -- To unsubscribe
send an email totime-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
time-nuts mailing list --time-nuts@lists.febo.com -- To unsubscribe send
an email totime-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
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To unsubscribe, go to and follow the instructions there.