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Time Dilation tinkering

M
MLewis
Thu, Mar 23, 2017 4:06 AM

Rather than commercial passenger flights, it used to be one could get
connections and fly along on transport, ferry or private flights,
typically for a (no-frills) low fee.

There are also flights made for testing equipment at altitude, including
radio, satellite, imaging or other sensing equipment. Rather than hiring
such, if it could be demonstrated that your experiment wouldn't
interfere with their test/survey/experiment instruments, you may find
someone sympathetic to letting you tag along. Local universities may
know of sympathetic companies or pilots. Or check with local flying
instructors or inspectors, who seem to know everything that's going on.
(A friend once had to accompany an imaging package on a Lear Jet. With
three hours rented and his tests completed in one, he got to sit at the
controls and buzz around the north until they had to return.)

The above would not only let you bring your powered experiment package
along to altitude, but not create a panic when commercial passengers or
cabin crew saw blinking lights or some such. And imagine if you're seen
hooking up a cable to a device and collecting data into a laptop... And
you could even be in trouble if seen doing anything with numbers that
wasn't obviously accounting.

On 22/03/2017 10:59 PM, Bob Bownes wrote:

It's not getting one past the airport authorities that's the issue. It's getting one that's powered up past them. ;)

Written from about 10,000'. :)

Rather than commercial passenger flights, it used to be one could get connections and fly along on transport, ferry or private flights, typically for a (no-frills) low fee. There are also flights made for testing equipment at altitude, including radio, satellite, imaging or other sensing equipment. Rather than hiring such, if it could be demonstrated that your experiment wouldn't interfere with their test/survey/experiment instruments, you may find someone sympathetic to letting you tag along. Local universities may know of sympathetic companies or pilots. Or check with local flying instructors or inspectors, who seem to know everything that's going on. (A friend once had to accompany an imaging package on a Lear Jet. With three hours rented and his tests completed in one, he got to sit at the controls and buzz around the north until they had to return.) The above would not only let you bring your powered experiment package along to altitude, but not create a panic when commercial passengers or cabin crew saw blinking lights or some such. And imagine if you're seen hooking up a cable to a device and collecting data into a laptop... And you could even be in trouble if seen doing anything with numbers that wasn't obviously accounting. On 22/03/2017 10:59 PM, Bob Bownes wrote: > It's not getting one past the airport authorities that's the issue. It's getting one that's powered up past them. ;) > > Written from about 10,000'. :)
BC
Bob Camp
Thu, Mar 23, 2017 11:33 AM

Hi

Back before GPS and similar systems, hauling Cs standards on commercial aircraft was
a bit more common than it is today. One of the critical tricks of the trade was knowing where
each power outlet was on a specific plane and how close it was to this or that seat. The next
trick was knowing how to talk the crew into letting you plug the gizmo in the seat next to yours
into that outlet. Sometimes the magic worked and other times you had to depend on your
battery pack. Needless to say, getting through the over ocean travel process with a dead
standard was not good news.

Bob

On Mar 22, 2017, at 10:59 PM, Bob Bownes bownes@gmail.com wrote:

It's not getting one past the airport authorities that's the issue. It's getting one that's powered up past them. ;)

Written from about 10,000'. :)

On Mar 22, 2017, at 20:15, Tom Van Baak tvb@LeapSecond.com wrote:

Chris Albertson wrote:

Why drive up a mountain?

"Because it's there" ;-)  And because there's a paved road, and it's free, and there's a place to stay overnight, and the mountain doesn't move. Plus a car makes a good portable time lab; you can share the experience with family or students or visiting time nuts; and a number of technical reasons.

But most importantly: you can remain at altitude as long as you want -- in order to accumulate just enough nanoseconds of time dilation to meet your experiment's S/N goal -- without running into (or much worse, going beyond) the flicker floor of your clocks.

There are several different ways to measure time dilation with atomic clocks. Some notes here:
http://leapsecond.com/pages/atomic-tom/

Take the clock with you inside the pressurized cabin of a commercial airliner

Yes, and this has been done many times. The first (1971) and most famous of all traveling clock relativity experiments is:
https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment

For vintage hp flying clock articles see:
https://www.febo.com/pipermail/time-nuts/2013-January/073743.html

Two modern examples are described here:

"Time flies"
http://www.npl.co.uk/news/time-flies

"Demonstrating Relativity by Flying Atomic Clocks"
http://www.npl.co.uk/upload/pdf/metromnia_issue18.pdf

/tvb

----- Original Message -----
From: Chris Albertson
To: Tom Van Baak ; Discussion of precise time and frequency measurement
Sent: Tuesday, March 21, 2017 7:12 PM
Subject: Re: [time-nuts] Time Dilation tinkering

"flight" there is the word.    Why drive up a mountain?  Take the clock with you inside the pressurized cabin of a commercial airliner next time you are on one of those 10 hour trans=pacific flights.  You be taller then any mountain and it is actually cheaper then a weather balloon.

Can you get a Rb clock past the TSA x-ray machine.  Maybe if you ask first.  There must be a way to hand cary specialized equipment.

On Tue, Mar 21, 2017 at 7:03 PM, Tom Van Baak tvb@leapsecond.com wrote:

But attached is one of the first plots where I put a SA.32m in a home-brew vacuum chamber and pulled down to a few inches of Hg for a few hours to simulate the low pressure of a flight up to 50 or 90,000 ft. For a high altitude relativity experiment -- where you'd like your clock to remain stable to parts in e-13 and not accumulate too many stray ns -- it's not a good sign when your clock changes by 2e-11 (that's more than 1 ns per minute) just because of ambient pressure changes.


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Hi Back before GPS and similar systems, hauling Cs standards on commercial aircraft was a bit more common than it is today. One of the critical tricks of the trade was knowing where each power outlet was on a specific plane and how close it was to this or that seat. The next trick was knowing how to talk the crew into letting you plug the gizmo in the seat next to yours into that outlet. Sometimes the magic worked and other times you had to depend on your battery pack. Needless to say, getting through the over ocean travel process with a dead standard was not good news. Bob > On Mar 22, 2017, at 10:59 PM, Bob Bownes <bownes@gmail.com> wrote: > > It's not getting one past the airport authorities that's the issue. It's getting one that's powered up past them. ;) > > Written from about 10,000'. :) > >> On Mar 22, 2017, at 20:15, Tom Van Baak <tvb@LeapSecond.com> wrote: >> >> Chris Albertson wrote: >>> Why drive up a mountain? >> >> "Because it's there" ;-) And because there's a paved road, and it's free, and there's a place to stay overnight, and the mountain doesn't move. Plus a car makes a good portable time lab; you can share the experience with family or students or visiting time nuts; and a number of technical reasons. >> >> But most importantly: you can remain at altitude as long as you want -- in order to accumulate just enough nanoseconds of time dilation to meet your experiment's S/N goal -- without running into (or much worse, going beyond) the flicker floor of your clocks. >> >> There are several different ways to measure time dilation with atomic clocks. Some notes here: >> http://leapsecond.com/pages/atomic-tom/ >> >> >>> Take the clock with you inside the pressurized cabin of a commercial airliner >> >> Yes, and this has been done many times. The first (1971) and most famous of all traveling clock relativity experiments is: >> https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment >> >> For vintage hp flying clock articles see: >> https://www.febo.com/pipermail/time-nuts/2013-January/073743.html >> >> Two modern examples are described here: >> >> "Time flies" >> http://www.npl.co.uk/news/time-flies >> >> "Demonstrating Relativity by Flying Atomic Clocks" >> http://www.npl.co.uk/upload/pdf/metromnia_issue18.pdf >> >> /tvb >> >> ----- Original Message ----- >> From: Chris Albertson >> To: Tom Van Baak ; Discussion of precise time and frequency measurement >> Sent: Tuesday, March 21, 2017 7:12 PM >> Subject: Re: [time-nuts] Time Dilation tinkering >> >> "flight" there is the word. Why drive up a mountain? Take the clock with you inside the pressurized cabin of a commercial airliner next time you are on one of those 10 hour trans=pacific flights. You be taller then any mountain and it is actually cheaper then a weather balloon. >> >> Can you get a Rb clock past the TSA x-ray machine. Maybe if you ask first. There must be a way to hand cary specialized equipment. >> >> On Tue, Mar 21, 2017 at 7:03 PM, Tom Van Baak <tvb@leapsecond.com> wrote: >> >> But attached is one of the first plots where I put a SA.32m in a home-brew vacuum chamber and pulled down to a few inches of Hg for a few hours to simulate the low pressure of a flight up to 50 or 90,000 ft. For a high altitude relativity experiment -- where you'd like your clock to remain stable to parts in e-13 and not accumulate too many stray ns -- it's not a good sign when your clock changes by 2e-11 (that's more than 1 ns per minute) just because of ambient pressure changes. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
E
EB4APL
Thu, Mar 23, 2017 1:43 PM

Not mentioning that the clock traveled in a passenger seat (even with
the seat belt fastened). The vision of a big box with  cables and a good
sized clock ticking (it was a Patek Philippe movement in early HP
Cesiums) frightened some passengers  and the person accompanying the
clock had to give a lot of explanations. The use of the word "atomic"
worsened things somewhat.

(Memories from Apollo flights good times)

Regards,

Ignacio, EB4APL

El 23/03/2017 a las 12:33, Bob Camp escribió:

Hi

Back before GPS and similar systems, hauling Cs standards on commercial aircraft was
a bit more common than it is today. One of the critical tricks of the trade was knowing where
each power outlet was on a specific plane and how close it was to this or that seat. The next
trick was knowing how to talk the crew into letting you plug the gizmo in the seat next to yours
into that outlet. Sometimes the magic worked and other times you had to depend on your
battery pack. Needless to say, getting through the over ocean travel process with a dead
standard was not good news.

Bob

On Mar 22, 2017, at 10:59 PM, Bob Bownes bownes@gmail.com wrote:

It's not getting one past the airport authorities that's the issue. It's getting one that's powered up past them. ;)

Written from about 10,000'. :)

On Mar 22, 2017, at 20:15, Tom Van Baak tvb@LeapSecond.com wrote:

Chris Albertson wrote:

Why drive up a mountain?

"Because it's there" ;-)  And because there's a paved road, and it's free, and there's a place to stay overnight, and the mountain doesn't move. Plus a car makes a good portable time lab; you can share the experience with family or students or visiting time nuts; and a number of technical reasons.

But most importantly: you can remain at altitude as long as you want -- in order to accumulate just enough nanoseconds of time dilation to meet your experiment's S/N goal -- without running into (or much worse, going beyond) the flicker floor of your clocks.

There are several different ways to measure time dilation with atomic clocks. Some notes here:
http://leapsecond.com/pages/atomic-tom/

Take the clock with you inside the pressurized cabin of a commercial airliner

Yes, and this has been done many times. The first (1971) and most famous of all traveling clock relativity experiments is:
https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment

For vintage hp flying clock articles see:
https://www.febo.com/pipermail/time-nuts/2013-January/073743.html

Two modern examples are described here:

"Time flies"
http://www.npl.co.uk/news/time-flies

"Demonstrating Relativity by Flying Atomic Clocks"
http://www.npl.co.uk/upload/pdf/metromnia_issue18.pdf

/tvb

----- Original Message -----
From: Chris Albertson
To: Tom Van Baak ; Discussion of precise time and frequency measurement
Sent: Tuesday, March 21, 2017 7:12 PM
Subject: Re: [time-nuts] Time Dilation tinkering

"flight" there is the word.    Why drive up a mountain?  Take the clock with you inside the pressurized cabin of a commercial airliner next time you are on one of those 10 hour trans=pacific flights.  You be taller then any mountain and it is actually cheaper then a weather balloon.

Can you get a Rb clock past the TSA x-ray machine.  Maybe if you ask first.  There must be a way to hand cary specialized equipment.

On Tue, Mar 21, 2017 at 7:03 PM, Tom Van Baak tvb@leapsecond.com wrote:

But attached is one of the first plots where I put a SA.32m in a home-brew vacuum chamber and pulled down to a few inches of Hg for a few hours to simulate the low pressure of a flight up to 50 or 90,000 ft. For a high altitude relativity experiment -- where you'd like your clock to remain stable to parts in e-13 and not accumulate too many stray ns -- it's not a good sign when your clock changes by 2e-11 (that's more than 1 ns per minute) just because of ambient pressure changes.


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.


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To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Not mentioning that the clock traveled in a passenger seat (even with the seat belt fastened). The vision of a big box with cables and a good sized clock ticking (it was a Patek Philippe movement in early HP Cesiums) frightened some passengers and the person accompanying the clock had to give a lot of explanations. The use of the word "atomic" worsened things somewhat. (Memories from Apollo flights good times) Regards, Ignacio, EB4APL El 23/03/2017 a las 12:33, Bob Camp escribió: > Hi > > Back before GPS and similar systems, hauling Cs standards on commercial aircraft was > a bit more common than it is today. One of the critical tricks of the trade was knowing where > each power outlet was on a specific plane and how close it was to this or that seat. The next > trick was knowing how to talk the crew into letting you plug the gizmo in the seat next to yours > into that outlet. Sometimes the magic worked and other times you had to depend on your > battery pack. Needless to say, getting through the over ocean travel process with a dead > standard was not good news. > > Bob > >> On Mar 22, 2017, at 10:59 PM, Bob Bownes <bownes@gmail.com> wrote: >> >> It's not getting one past the airport authorities that's the issue. It's getting one that's powered up past them. ;) >> >> Written from about 10,000'. :) >> >>> On Mar 22, 2017, at 20:15, Tom Van Baak <tvb@LeapSecond.com> wrote: >>> >>> Chris Albertson wrote: >>>> Why drive up a mountain? >>> "Because it's there" ;-) And because there's a paved road, and it's free, and there's a place to stay overnight, and the mountain doesn't move. Plus a car makes a good portable time lab; you can share the experience with family or students or visiting time nuts; and a number of technical reasons. >>> >>> But most importantly: you can remain at altitude as long as you want -- in order to accumulate just enough nanoseconds of time dilation to meet your experiment's S/N goal -- without running into (or much worse, going beyond) the flicker floor of your clocks. >>> >>> There are several different ways to measure time dilation with atomic clocks. Some notes here: >>> http://leapsecond.com/pages/atomic-tom/ >>> >>> >>>> Take the clock with you inside the pressurized cabin of a commercial airliner >>> Yes, and this has been done many times. The first (1971) and most famous of all traveling clock relativity experiments is: >>> https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment >>> >>> For vintage hp flying clock articles see: >>> https://www.febo.com/pipermail/time-nuts/2013-January/073743.html >>> >>> Two modern examples are described here: >>> >>> "Time flies" >>> http://www.npl.co.uk/news/time-flies >>> >>> "Demonstrating Relativity by Flying Atomic Clocks" >>> http://www.npl.co.uk/upload/pdf/metromnia_issue18.pdf >>> >>> /tvb >>> >>> ----- Original Message ----- >>> From: Chris Albertson >>> To: Tom Van Baak ; Discussion of precise time and frequency measurement >>> Sent: Tuesday, March 21, 2017 7:12 PM >>> Subject: Re: [time-nuts] Time Dilation tinkering >>> >>> "flight" there is the word. Why drive up a mountain? Take the clock with you inside the pressurized cabin of a commercial airliner next time you are on one of those 10 hour trans=pacific flights. You be taller then any mountain and it is actually cheaper then a weather balloon. >>> >>> Can you get a Rb clock past the TSA x-ray machine. Maybe if you ask first. There must be a way to hand cary specialized equipment. >>> >>> On Tue, Mar 21, 2017 at 7:03 PM, Tom Van Baak <tvb@leapsecond.com> wrote: >>> >>> But attached is one of the first plots where I put a SA.32m in a home-brew vacuum chamber and pulled down to a few inches of Hg for a few hours to simulate the low pressure of a flight up to 50 or 90,000 ft. For a high altitude relativity experiment -- where you'd like your clock to remain stable to parts in e-13 and not accumulate too many stray ns -- it's not a good sign when your clock changes by 2e-11 (that's more than 1 ns per minute) just because of ambient pressure changes. >>> >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >