Re: [time-nuts] Einstein Special on PBS
On Fri, November 27, 2015 9:37 am, Mike Feher wrote: > the period of the hyperfine transitions must change as well, to > make the defined second longer or shorter. So, in these examples the > elevation does not change the time, but the way the atoms behave. That gets into a philosophical question of what defines time. You seem to take the view that time is some kind of Platonic ideal, and we can compare how closely a physical phenomenon matches that ideal. But how do you define or measure time other than changes from one physical state to another? And if every state change process down to the quantum atomic level changes rate when referenced to the identical processes in a different gravity potential or acceleration, how do you define which is the "correct" rate? How would you objectively tell the difference between time passing at a different rate, and the Platonic ideal time passing at a constant rate and literally every physical process progressing at a different rate referred to the Platonic ideal time? -- Chris Caudle ___ 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.
Re: [time-nuts] Einstein Special on PBS
The whole "t" thing was bothering me in John's explanation, so I
showed it to my son the physicist. He tells me that John's
explanation comes from Brian Greene's book, "The Elegant Universe"...
A very popular coffee table book, aimed at the same market as those
by Stephen Hawking.
Greene's explanation breaks the 4 known dimensions of space into
X,Y,Z, and C*T That arbitrary multiplication of time by the
constant C forces all four dimensions be in terms of distance.
In the internet traffic where people seem to spend a lot of time
discussing this model, it is common to forget that t is really C*t,
and say silly things like the velocity of t in meters/second...
Additionally, the dt/dt =0 thing needs the "t"'s to be different,
say "t" and Tao. where Tao is the time on the moving frame, and t
is the same time as viewed from the stationary frame...
There are lots of reasons why one might want to simplify a set
of equations by multiplying by an arbitrary constant, and then
factoring it out later... It might make the math easier, but it
also can completely change the model you are working on.
According to my son, that "simple" explanation confuses things more
than it helps if you are actually doing physics, but does tend to
make an intuitive feeling for special and general relativity available
to the unwashed masses.
-Chuck Harris
Didier Juges wrote:
Wow. So elegantly simple explanation, thanks John!
On November 27, 2015 2:54:51 PM CST, John Miles wrote:
So, here's how I finally grokked this stuff. c, the speed of light in
a vacuum, is often spoken of as a "speed limit" that nothing can ever
exceed. That's a bad way to put it, and people who have expressed it
that way in popular science writing for 100 years should feel bad.
Instead, the way to visualize relativity is to realize that c is the
*only* speed at which anything can travel. You are always moving at
300,000,000 meters per second, whether you want to or not. But you're
doing it through all four dimensions including time. If you choose to
remain stationary in (x,y,z), then all of your velocity is in the t
direction. If you move through space at 100,000,000 meters per second
in space, then your velocity in the t direction is 283,000,000 meters
per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)
It doesn't make sense to speak of moving a certain number of "meters"
through time, so your location in time itself is what has to change.
You won't perceive any drift in your personal timebase when you move in
space, any more than you will perceive a change in your location
relative to yourself. ("No matter where you go, there you are.") But
an independent observer will see a person who's moving at 100,000,000
meters per second in x,y,z and 283,000,000 meters per second in t.
They see you moving in space, in the form of a location change, and
they also see you moving in time, in the form of a disagreement between
their perception of elapsed time and your own.
Likewise, if you spend all of your velocity allowance in (x,y,z), your
t component is necessarily zero. Among other inconvenient effects that
occur at dt/dt=0, you won't get any closer to your destination, even
though your own watch is still ticking normally. Particles moving near
c experience this effect from their point of view, even while we watch
them smash into their targets at unimaginable speeds.
This is special relativity in action. The insight behind general
relativity is twofold: 1) movement caused by the acceleration of
gravity is indistinguishable from movement caused by anything else; and
2) you don't even have to move, just feel the acceleration. That
second part was what really baked peoples' noodles. It is what's
responsible for the disagreement between the two 5071As.
-- john, KE5FX
Miles Design LLC
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[time-nuts] Einstein Special on PBS
Yep, been there, done that... I own a Worden gravity meter. Gravity mapping is a highly developed technology. Not just Everest, but the whole planet: ___ 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.
Re: [time-nuts] Einstein Special on PBS
The reference was probably a bit too obscure for an international audience. :) https://www.youtube.com/watch?v=VPJqIT7a3qA -- john, KE5FX Miles Design LLC > Hi John, > > Thank you very much for this explanation, I found it very "explicative". > What I am not able to grasp is the sense of the phrase " That second > part was what really baked peoples' noodles". I think that is some > colloquial but not being English my native language I can't figure out > its meaning. > > Thank you, > Ignacio > ___ 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.
Re: [time-nuts] Einstein Special on PBS
Mark, Gravity mapping is a highly developed technology. Not just Everest, but the whole planet: http://op.gfz-potsdam.de/grace/results/grav/g001_eigen-grace01s.html http://www.geology.sdsu.edu/kmlgeology/kmz/gravity_grace/grace.jpg Or use this search and enjoy every image. It's just stunning: https://www.google.com/search?tbm=isch&q=grace+gravity+map /tvb - Original Message - From: "Mark Sims" To: Sent: Sunday, November 29, 2015 12:13 PM Subject: [time-nuts] Einstein Special on PBS > Another thing to consider is the gravity anomaly caused by that hunk of > granite beneath your clock (or above it in a mine). Hmmm, what is the clock > shift at the top of Mt Everest that is due to the mountain and not the > altitude? ___ 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.
Re: [time-nuts] Einstein Special on PBS
Hi > On Nov 29, 2015, at 3:15 PM, Hal Murray wrote: > > > kb...@n1k.org said: >> If you dig into the gravity stuff, they get into questions like “do we put >> in a term for the gravitational effects of Pluto? Yes, there are Gravity >> Nuts…. > > Things like that have a significant influence on planetary orbits. Do they > have a measurable influence on Earth satellite orbits? (as seen from Earth) If you look at it carefully enough, then yes things like outer planet orbits have an impact both on solid earth tides and on orbits or satellites. Just as with our modeling of time sources, you have to be pretty careful with your measurements to pull something like that out of the noise. Bob > > -- > These are my opinions. I hate spam. > > > > ___ > 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.
Re: [time-nuts] Einstein Special on PBS
On 11/29/15 12:13 PM, Mark Sims wrote: Another thing to consider is the gravity anomaly caused by that hunk of granite beneath your clock (or above it in a mine). Hmmm, what is the clock shift at the top of Mt Everest that is due to the mountain and not the altitude? ___ t when going deep.. the Homestake mine in South Dakota is something like 2500m (8000 ft) deep. There's a DoE funded research facility somewhere deep for nuclear experiments. There could well be atomic clocks already down there. https://en.wikipedia.org/wiki/Sanford_Underground_Research_Facility https://en.wikipedia.org/wiki/Large_Underground_Xenon_experiment is about halfway down (I think the lower part of the mine is still flooded) ___ 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.
Re: [time-nuts] Einstein Special on PBS
It's not exactly a rigorous explanation, but I think it's a good memory aid. Once you realize that c is a 4D constant rather than a scalar speed, you can work out for yourself which way clock measurements are skewed from various points of view. -- john, KE5FX > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Didier > Juges > Sent: Sunday, November 29, 2015 11:20 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Einstein Special on PBS > > Wow. So elegantly simple explanation, thanks John! > > On November 27, 2015 2:54:51 PM CST, John Miles wrote: > >So, here's how I finally grokked this stuff. c, the speed of light in > >a vacuum, is often spoken of as a "speed limit" that nothing can ever > >exceed. That's a bad way to put it, and people who have expressed it > >that way in popular science writing for 100 years should feel bad. > ___ 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.
Re: [time-nuts] Einstein Special on PBS
Hi John,
Thank you very much for this explanation, I found it very "explicative".
What I am not able to grasp is the sense of the phrase " That second
part was what really baked peoples' noodles". I think that is some
colloquial but not being English my native language I can't figure out
its meaning.
Thank you,
Ignacio
El 27/11/2015 a las 21:54, John Miles wrote:
So, here's how I finally grokked this stuff. c, the speed of light in a vacuum, is often
spoken of as a "speed limit" that nothing can ever exceed. That's a bad way to
put it, and people who have expressed it that way in popular science writing for 100
years should feel bad.
Instead, the way to visualize relativity is to realize that c is the *only*
speed at which anything can travel. You are always moving at 300,000,000
meters per second, whether you want to or not. But you're doing it through all
four dimensions including time. If you choose to remain stationary in (x,y,z),
then all of your velocity is in the t direction. If you move through space at
100,000,000 meters per second in space, then your velocity in the t direction
is 283,000,000 meters per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)
It doesn't make sense to speak of moving a certain number of "meters" through time, so
your location in time itself is what has to change. You won't perceive any drift in your personal
timebase when you move in space, any more than you will perceive a change in your location relative
to yourself. ("No matter where you go, there you are.") But an independent observer
will see a person who's moving at 100,000,000 meters per second in x,y,z and 283,000,000 meters per
second in t. They see you moving in space, in the form of a location change, and they also see
you moving in time, in the form of a disagreement between their perception of elapsed time and your
own.
Likewise, if you spend all of your velocity allowance in (x,y,z), your t
component is necessarily zero. Among other inconvenient effects that occur at
dt/dt=0, you won't get any closer to your destination, even though your own
watch is still ticking normally. Particles moving near c experience this
effect from their point of view, even while we watch them smash into their
targets at unimaginable speeds.
This is special relativity in action. The insight behind general relativity is
twofold: 1) movement caused by the acceleration of gravity is
indistinguishable from movement caused by anything else; and 2) you don't even
have to move, just feel the acceleration. That second part was what really
baked peoples' noodles. It is what's responsible for the disagreement between
the two 5071As.
-- john, KE5FX
Miles Design LLC
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Re: [time-nuts] Einstein Special on PBS
Chris, A few years after my Mt Rainier trip I looked into doing the same experiment down a mine. But besides having mountains Seattle also has the Pacific ocean so there are any number of commercial and research deep sea operations around here. I thought it would fun to put a few 5071A and batteries into a bathysphere and send them down as many thousand feet as possible for a couple of days. One advantage is that many of them have long fiber data links and so I thought it might be possible to compare clocks live during the experiment instead of having to wait for the round-trip. TDR could be used to compensate for fiber tempco. The theory is simple. Below sea level gravity falls by 1/r and above sea level gravity falls by 1/r^2. The magic number, W0, is -6.969e-10 which how slow Earth's SI second is compared to "free space". In other words, clocks speed up on either side of mean sea level. Yes, an atomic clock can be used as a depth gauge as well as an altimeter. You're probably thinking it would be fun to detect the difference between 1/r and 1/r^2 effects. But the problem is that the earth has a radius of 3900 miles so for a couple of miles above or below the surface, 1/r and 1/r^2 look identical. That is, you get the same blueshift: 1.1e-16/meter. /tvb - Original Message - From: "Chris Howard" To: Sent: Friday, November 27, 2015 7:04 PM Subject: Re: [time-nuts] Einstein Special on PBS > > The mountain thing has been done. > > Someone needs to take their > clock to the bottom of the deepest mine (2.4 miles). > ___ 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.
Re: [time-nuts] Einstein Special on PBS
t...@leapsecond.com said: > I'm not sure I understand your elevation question. Are you talking about > elevation as in mountain vs. sea level altitude? Or elevation as in > satellite Az/El? I was thinking of the elevation of the receiver as in mountain vs sea level. I think the question I was trying to ask is: Do the calculations for a consumer grade GPS include relativistic corrections for the elevation of the receiver? How about a survey grade receiver? kb...@n1k.org said: > Most survey work is done as a âdelta from known referencesâ. Itâs much > like > common view time transfer. That alone takes care of a whole raft of things. I assume the delta includes elevation as well as lat/long. That may make relativistic corrections insignificant. A week or so ago, I stopped to chat with a surveyor working on a lot a block from here. He was using old fashioned optical gear. (Standard story 42. The house next door was built with reference to the fences. The fence was off, so that house is actually too close to the lot line. His job was to make sure the new house didn't get into similar troubles.) He mentioned that GPS gear has the problem of plate motion. That's a bug if you want to survey lot lines but a feature if you want to measure earthquake fault creep. (Standard number is plates move about as fast as your fingernails grow, ballpark of an inch a year. I'm a few miles from the San Andreas.) -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] Einstein Special on PBS
kb...@n1k.org said: > If you dig into the gravity stuff, they get into questions like âdo we put > in a term for the gravitational effects of Pluto? Yes, there are Gravity > Nutsâ¦. Things like that have a significant influence on planetary orbits. Do they have a measurable influence on Earth satellite orbits? (as seen from Earth) -- These are my opinions. I hate spam. ___ 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] Einstein Special on PBS
Another thing to consider is the gravity anomaly caused by that hunk of granite beneath your clock (or above it in a mine). Hmmm, what is the clock shift at the top of Mt Everest that is due to the mountain and not the altitude? ___ 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.
Re: [time-nuts] Einstein Special on PBS
Wow. So elegantly simple explanation, thanks John!
On November 27, 2015 2:54:51 PM CST, John Miles wrote:
>So, here's how I finally grokked this stuff. c, the speed of light in
>a vacuum, is often spoken of as a "speed limit" that nothing can ever
>exceed. That's a bad way to put it, and people who have expressed it
>that way in popular science writing for 100 years should feel bad.
>
>Instead, the way to visualize relativity is to realize that c is the
>*only* speed at which anything can travel. You are always moving at
>300,000,000 meters per second, whether you want to or not. But you're
>doing it through all four dimensions including time. If you choose to
>remain stationary in (x,y,z), then all of your velocity is in the t
>direction. If you move through space at 100,000,000 meters per second
>in space, then your velocity in the t direction is 283,000,000 meters
>per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)
>
>It doesn't make sense to speak of moving a certain number of "meters"
>through time, so your location in time itself is what has to change.
>You won't perceive any drift in your personal timebase when you move in
>space, any more than you will perceive a change in your location
>relative to yourself. ("No matter where you go, there you are.") But
>an independent observer will see a person who's moving at 100,000,000
>meters per second in x,y,z and 283,000,000 meters per second in t.
>They see you moving in space, in the form of a location change, and
>they also see you moving in time, in the form of a disagreement between
>their perception of elapsed time and your own.
>
>Likewise, if you spend all of your velocity allowance in (x,y,z), your
>t component is necessarily zero. Among other inconvenient effects that
>occur at dt/dt=0, you won't get any closer to your destination, even
>though your own watch is still ticking normally. Particles moving near
>c experience this effect from their point of view, even while we watch
>them smash into their targets at unimaginable speeds.
>
>This is special relativity in action. The insight behind general
>relativity is twofold: 1) movement caused by the acceleration of
>gravity is indistinguishable from movement caused by anything else; and
>2) you don't even have to move, just feel the acceleration. That
>second part was what really baked peoples' noodles. It is what's
>responsible for the disagreement between the two 5071As.
>
>-- john, KE5FX
>Miles Design LLC
>
>> Hi Mike,
>>
>> The time rate does remain the same - at the device. The problem is
>the idea
>> that it is the hyperfine transitions that determine the time...
>
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Re: [time-nuts] Einstein Special on PBS
Hi > On Nov 29, 2015, at 11:31 AM, Tom Van Baak wrote: > > Hal, > > Right. The orbits are nominally circular -- but not exactly. The set of > orbital parameters cover these details. A quick google search suggests the > eccentricity for GPS is around 0.01. Still, that's enough to cause +/- 23 ns > of accumulated phase error per orbit. I'm pretty sure the receivers take care > of this math, since eccentricity is a key part of any orbit model. I wish we > could see the source code to a GPS timing receiver. > > I'm not sure I understand your elevation question. Are you talking about > elevation as in mountain vs. sea level altitude? Or elevation as in satellite > Az/El? > > GPS satellites in view are about 20,000 km (overhead) to about 25,000 km > (horizon) away, so the signal gets to you within about 65 to 85 ms. Whether > you apply the full 4.5e-10 relativistic correction or no correction to the SV > clock at all, it makes only a 1 cm time-of-arrival difference. That's why I > said for trilateral navigation purposes, the relativistic effects are in the > noise. For UTC time-transfer, however, an uncorrected 4.5e-10 frequency error > would continuously accumulate, giving 38 us/day phase error, the number you > often hear. > > About survey grade -- I suspect the post-processing takes into account > anything you can think of, from the shape of the antennas to space weather to > the phase of the moon (literally). Most survey work is done as a “delta from known references”. It’s much like common view time transfer. That alone takes care of a whole raft of things. If you dig into the gravity stuff, they get into questions like “do we put in a term for the gravitational effects of Pluto? Yes, there are Gravity Nuts…. Bob > > /tvb > > - Original Message - > From: "Hal Murray" > To: "Discussion of precise time and frequency measurement" > > Cc: > Sent: Saturday, November 28, 2015 2:37 PM > Subject: Re: [time-nuts] Einstein Special on PBS > > >> >> hol...@hotmail.com said: >>> The GPS spec implies the satellites have a fixed frequency offset to >>> compensate for relativistic effects. But do they actually dynamically and/ >>> or individually adjust the frequency to adjust for orbit variations and >>> eccentricities? >> >> I think the orbits are circular so the frequency won't depend on the orbital >> position. >> >> The next question is does the math in the receiver have to correct for >> changes due to elevation? Does it become relevant if you are trying for >> survey grade results? >> >> -- >> These are my opinions. I hate spam. >> > > ___ > 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.
Re: [time-nuts] Einstein Special on PBS
Hal, Right. The orbits are nominally circular -- but not exactly. The set of orbital parameters cover these details. A quick google search suggests the eccentricity for GPS is around 0.01. Still, that's enough to cause +/- 23 ns of accumulated phase error per orbit. I'm pretty sure the receivers take care of this math, since eccentricity is a key part of any orbit model. I wish we could see the source code to a GPS timing receiver. I'm not sure I understand your elevation question. Are you talking about elevation as in mountain vs. sea level altitude? Or elevation as in satellite Az/El? GPS satellites in view are about 20,000 km (overhead) to about 25,000 km (horizon) away, so the signal gets to you within about 65 to 85 ms. Whether you apply the full 4.5e-10 relativistic correction or no correction to the SV clock at all, it makes only a 1 cm time-of-arrival difference. That's why I said for trilateral navigation purposes, the relativistic effects are in the noise. For UTC time-transfer, however, an uncorrected 4.5e-10 frequency error would continuously accumulate, giving 38 us/day phase error, the number you often hear. About survey grade -- I suspect the post-processing takes into account anything you can think of, from the shape of the antennas to space weather to the phase of the moon (literally). /tvb - Original Message - From: "Hal Murray" To: "Discussion of precise time and frequency measurement" Cc: Sent: Saturday, November 28, 2015 2:37 PM Subject: Re: [time-nuts] Einstein Special on PBS > > hol...@hotmail.com said: >> The GPS spec implies the satellites have a fixed frequency offset to >> compensate for relativistic effects. But do they actually dynamically and/ >> or individually adjust the frequency to adjust for orbit variations and >> eccentricities? > > I think the orbits are circular so the frequency won't depend on the orbital > position. > > The next question is does the math in the receiver have to correct for > changes due to elevation? Does it become relevant if you are trying for > survey grade results? > > -- > These are my opinions. I hate spam. > ___ 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.
Re: [time-nuts] Einstein Special on PBS
The mountain thing has been done. Someone needs to take their clock to the bottom of the deepest mine (2.4 miles). ___ 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.
Re: [time-nuts] Einstein Special on PBS
hol...@hotmail.com said: > The GPS spec implies the satellites have a fixed frequency offset to > compensate for relativistic effects. But do they actually dynamically and/ > or individually adjust the frequency to adjust for orbit variations and > eccentricities? I think the orbits are circular so the frequency won't depend on the orbital position. The next question is does the math in the receiver have to correct for changes due to elevation? Does it become relevant if you are trying for survey grade results? -- These are my opinions. I hate spam. ___ 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.
Re: [time-nuts] Einstein Special on PBS
Hi Since you have massive doppler on the signals, it’s not practical to get frequency directly from the SV’s. All of our “frequency” information comes from time data extracted one way or the other from the signal. Either we do it directly from the broadcast data or indirectly from stuff like carrier phase comparisons. The quality of the time (and thus frequency) from GPS has gotten steadily better over the years. It is quite possible that they have added this or that to the steering process as things evolved. It clock tuning one of those things? Who knows… I suspect it is, but I have no real data to back up that guess. Bob > On Nov 28, 2015, at 12:05 PM, Mark Sims wrote: > > The GPS spec implies the satellites have a fixed frequency offset to > compensate for relativistic effects. But do they actually dynamically and/or > individually adjust the frequency to adjust for orbit variations and > eccentricities? > ___ > 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.
Re: [time-nuts] Einstein Special on PBS
Hi, On 11/28/2015 06:05 PM, Mark Sims wrote: The GPS spec implies the satellites have a fixed frequency offset to compensate for relativistic effects. The spec actually points out that explicitly. This is the General Relativity shift due to different gravitational position of the satellites. But do they actually dynamically and/or individually adjust the frequency to adjust for orbit variations and eccentricities? No, this is what the user will have to do, as this depends on where the user receiver is, as these effects shift with place of observation of the orbit. For normal C/A-code receivers, this only turns out as the doppler shift, and once locked, the carrier control loop cancels it out and the pseudo-ranges only use the code-phase. Cheers, Magnus ___ 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.
Re: [time-nuts] Einstein Special on PBS
Mark, The clocks themselves are not physically adjusted but numerical corrections (both clock and especially, orbit) for each satellite are updated as often as once every two hours. This is all part of the data stream that's sent down to the receiver. /tvb - Original Message - From: "Mark Sims" To: Sent: Saturday, November 28, 2015 9:05 AM Subject: [time-nuts] Einstein Special on PBS > The GPS spec implies the satellites have a fixed frequency offset to > compensate for relativistic effects. But do they actually dynamically and/or > individually adjust the frequency to adjust for orbit variations and > eccentricities? > ___ ___ 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] Einstein Special on PBS
The GPS spec implies the satellites have a fixed frequency offset to compensate for relativistic effects. But do they actually dynamically and/or individually adjust the frequency to adjust for orbit variations and eccentricities? ___ 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.
Re: [time-nuts] Einstein Special on PBS
Hi ….but … As part of the time steering of the system, the ground segment constantly plays games with the total correction of each SV. Even with no offset, they still would bring it all into alignment. Yes it would be a major pain to do so with a “couple of mHz” error in the mix. I suspect that there are some pretty involved corrections that take care of just about anything that can be calculated. Bob > On Nov 28, 2015, at 5:16 AM, Magnus Danielson > wrote: > > The trouble is that they experience different acceleration, due to gravity, > and this yanks the experienced time. In the relativistic world, the concept > of time is not consistent between locations, and the effect of acceleration > between two locations shift it, and this is a consequence of a fixed speed of > light. This is the consequences of fixed speed of light, that the rate of > time needs to shift and this is the bizarreness of relativity that made many > physics initially not accept relativity. Over the 100 years, we have seen > again and again that this model actually makes sense for all the observations > we have. > > Elevating a clock from the earth, alters it's experienced gravitational > potential, the gravitational acceleration will be different. This is similar > to sending the clock towards us in a constant rate. Our experience of their > rate of time will be different, and so will they. Our gravitational > acceleration will from the top of the mountain look like sending us away from > them. For both cases the light speed is constant, so we can only yank the > rate of time, because the physics of the clocks at each such location does > not yank. > > Think of the oscillators being modeled as > > O1(t) = cos(2*pi*f0*T1(t)) > O2(t) = cos(2*pi*f0*T2(t)) > > T1(t) and T2(t) being local time functions. With the clocks at the same > location or otherwise similar locations, these will be about the same. The > physics of the clock sets f0. It's only when we change the characteristics > that alter T1 and T2 that we can observe that difference. The time t being > here some arbitrary non-observable time. > > Usually we get away with letting T1 and T2 be t directly, but the fixed speed > of light need us to alter these. > > If you now take two clocks of different physics (Cs and H-maser) and forms > two pairs. One that stays and one that goes to the top. Each pair will be > consistent, to the degree they are for normal systematics, but the mountain > pair will both experience the same shift compared to the valley pair. > > Cheers, > Magnus > > On 11/27/2015 07:10 PM, Mike Feher wrote: >> Bob - >> >> Thanks for attempting to make me see the light. But, I still do not. You >> said it yourself that hyperfine transitions remain the same. Since "time" on >> these device are derived from these transitions, they should also remain the >> same. I agree, from a relativistic point of vie the time will be different. >> I am just not convinced that using these types of clocks will demonstrate >> that. Thanks - Mike >> >> Mike B. Feher, EOZ Inc. >> 89 Arnold Blvd. >> Howell, NJ, 07731 >> 732-886-5960 office >> 908-902-3831 cell >> >> >> -----Original Message- >> From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Stewart >> Sent: Friday, November 27, 2015 12:48 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Einstein Special on PBS >> >> Hi Mike, >> I'm far from an expert on this, but what you're missing is that time and >> space isn't the same between any two points that are located in different >> gravity gradients and/or moving at different relative velocities. The >> hyperfine transitions are happening at the same local rate whether the Cs >> device is on planet earth, in orbit around the earth, or in close proximity >> to the sun or even a black hole. But, all of these examples are happening >> in different space-time environments (i.e. different local frames), so that >> "relative" to each other, they are experiencing time at different rates. >> >> It might help to think of it in terms of doppler effect, though this is not >> an exact comparison. But, if you have two clocks that are moving away from >> each other, they may very well be precisely synchronous, but because of the >> doppler effect, any measurement you make will show them to be running at >> different rates. Because of the effects of gravity, watches at different >> altitudes appear to run at different rates to the outsider, although to the >> pe
Re: [time-nuts] Einstein Special on PBS
The trouble is that they experience different acceleration, due to gravity, and this yanks the experienced time. In the relativistic world, the concept of time is not consistent between locations, and the effect of acceleration between two locations shift it, and this is a consequence of a fixed speed of light. This is the consequences of fixed speed of light, that the rate of time needs to shift and this is the bizarreness of relativity that made many physics initially not accept relativity. Over the 100 years, we have seen again and again that this model actually makes sense for all the observations we have. Elevating a clock from the earth, alters it's experienced gravitational potential, the gravitational acceleration will be different. This is similar to sending the clock towards us in a constant rate. Our experience of their rate of time will be different, and so will they. Our gravitational acceleration will from the top of the mountain look like sending us away from them. For both cases the light speed is constant, so we can only yank the rate of time, because the physics of the clocks at each such location does not yank. Think of the oscillators being modeled as O1(t) = cos(2*pi*f0*T1(t)) O2(t) = cos(2*pi*f0*T2(t)) T1(t) and T2(t) being local time functions. With the clocks at the same location or otherwise similar locations, these will be about the same. The physics of the clock sets f0. It's only when we change the characteristics that alter T1 and T2 that we can observe that difference. The time t being here some arbitrary non-observable time. Usually we get away with letting T1 and T2 be t directly, but the fixed speed of light need us to alter these. If you now take two clocks of different physics (Cs and H-maser) and forms two pairs. One that stays and one that goes to the top. Each pair will be consistent, to the degree they are for normal systematics, but the mountain pair will both experience the same shift compared to the valley pair. Cheers, Magnus On 11/27/2015 07:10 PM, Mike Feher wrote: Bob - Thanks for attempting to make me see the light. But, I still do not. You said it yourself that hyperfine transitions remain the same. Since "time" on these device are derived from these transitions, they should also remain the same. I agree, from a relativistic point of vie the time will be different. I am just not convinced that using these types of clocks will demonstrate that. Thanks - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Stewart Sent: Friday, November 27, 2015 12:48 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Einstein Special on PBS Hi Mike, I'm far from an expert on this, but what you're missing is that time and space isn't the same between any two points that are located in different gravity gradients and/or moving at different relative velocities. The hyperfine transitions are happening at the same local rate whether the Cs device is on planet earth, in orbit around the earth, or in close proximity to the sun or even a black hole. But, all of these examples are happening in different space-time environments (i.e. different local frames), so that "relative" to each other, they are experiencing time at different rates. It might help to think of it in terms of doppler effect, though this is not an exact comparison. But, if you have two clocks that are moving away from each other, they may very well be precisely synchronous, but because of the doppler effect, any measurement you make will show them to be running at different rates. Because of the effects of gravity, watches at different altitudes appear to run at different rates to the outsider, although to the person wearing the watch, nothing has actually changed; it is the other person's watch that is acting funny. So, essentially, a clock sitting on the ground at sea level is running in a very slightly different space time than one that is sitting on a mountain. And when you place a clock in orbit, you also have 14,000 odd MPH of velocity that's also having an impact on the space-time of that object. As a result, when you bring the prodigal clock back to sea level, it will have experienced a slightly different amount of time than the one at sea level. Note that the prodigal clock hasn't run at a different rate. It has actually experienced time running at a different rate from that of the clock on the ground. Bob From: Mike Feher To: 'Discussion of precise time and frequency measurement' Sent: Friday, November 27, 2015 9:37 AM Subject: Re: [time-nuts] Einstein Special on PBS I just do not get it. I know that now I am 70 and my good smart days are behind me, but, this shou
Re: [time-nuts] Einstein Special on PBS
Hi, On 11/27/2015 05:03 PM, Tom Van Baak wrote: They mentioned some "6 miles per day" offset due to GPS relativity effects. I think this is the sum of both special relativity (time dilation) and general relativity (gravitational) effects. The GR correction is 45 microseconds a day fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a day, I'm not sure that GPS coordinates would drift that fast - aren't most of the corrections in the same direction? Hi Tim, Correct. Here's from the "rel" program (in my http://leapsecond.com/tools/ folder): C:\tvb\NPR>rel 2km 14000kph ** Altitude 2000.000 m (65616797.900 ft, 12427.424 mi) 5.274e-010 blueshift 1898630.424377 ps/hour 45567.130185 ns/day ** Velocity 3888.889 m/s (14000.000 km/h, 8699.197 mph) -8.414e-011 redshift -302888.070815 ps/hour -7269.313700 ns/day ** Net effect (GR+SR) 4.433e-010 shift 1595742.353562 ps/hour 38297.816485 ns/day What this means is that as a *source of UTC*, GPS would in fact be off by 38 us per day if you forgot about relativity when you designed it. But, you're right, you cannot blindly turn that "38 us/day" into "11 km/day". As long as *all* the GPS clocks are running too fast or too slow and as long as the receivers know what that offset is, the navigation system would still work just fine, relativity or not. This is true for any sort of triangulation (actually, trilateration) system. GPS is a PNT (Position, Navigation, and Timing) system. So while GPS is really cool, and relativity is really cool, the navigation part of GPS does not "depend" on relativity, per-se. As found in IS-GPS-200H: http://www.gps.gov/technical/icwg/IS-GPS-200H.pdf 8<--- 3.3.1.1 Frequency Plan. For Block IIA, IIR, IIR-M, and IIF satellites, the requirements specified in this IS shall pertain to the signal contained within two 20.46 MHz bands; one centered about the L1 nominal frequency and the other centered about the L2 nominal frequency (see Table 3-Vb). For GPS III and subsequent satellites, the requirements specified in this IS shall pertain to the signal contained within two 30.69 MHz bands; one centered about the L1 nominal frequency and the other centered about the L2 nominal frequency (see Table 3-Vc). The carrier frequencies for the L1 and L2 signals shall be coherently derived from a common frequency source within the SV. The nominal frequency of this source -- as it appears to an observer on the ground -- is 10.23 MHz. The SV carrier frequency and clock rates -- as they would appear to an observer located in the SV -- are offset to compensate for relativistic effects. The clock rates are offset by ∆ f/f = -4.4647E-10, equivalent to a change in the P-code chipping rate of 10.23 MHz offset by a ∆f = -4.5674E-3 Hz. This is equal to 10.229954326 MHz. The nominal carrier frequencies (f0) shall be 1575.42 MHz, and 1227.6 MHz for L1 and L2, respectively. --->8 There is however relativistic effects that the user equipment must compensate for, as it depends on the position of the user observation and shifts will be different for each user or for that matter for the user the shift will be different for each satellite. Cheers, Magnus ___ 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.
Re: [time-nuts] Einstein Special on PBS
Hi John,
I hadn't run into this idea before, and I like it. But I have a problem with
the statement:. "If you move through space at 100,000,000 meters per second in
space, then your velocity in the t direction is 283,000,000 meters per second
(because sqrt(100E6^2 + 283E6^2) = 300E6.)" The problem is that your velocity
in the t direction remains the same to yourself, because your velocity as
compared to yourself is always zero. So, yes, velocity with respect to some
other object does change the rate of time as compared to that other object.
But, as is understood from reading your whole post, time is always moving at
the same rate for the one observing himself.
Bob
From: John Miles
To: 'Discussion of precise time and frequency measurement'
Sent: Friday, November 27, 2015 2:54 PM
Subject: Re: [time-nuts] Einstein Special on PBS
So, here's how I finally grokked this stuff. c, the speed of light in a
vacuum, is often spoken of as a "speed limit" that nothing can ever exceed.
That's a bad way to put it, and people who have expressed it that way in
popular science writing for 100 years should feel bad.
Instead, the way to visualize relativity is to realize that c is the *only*
speed at which anything can travel. You are always moving at 300,000,000
meters per second, whether you want to or not. But you're doing it through all
four dimensions including time. If you choose to remain stationary in (x,y,z),
then all of your velocity is in the t direction. If you move through space at
100,000,000 meters per second in space, then your velocity in the t direction
is 283,000,000 meters per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)
It doesn't make sense to speak of moving a certain number of "meters" through
time, so your location in time itself is what has to change. You won't
perceive any drift in your personal timebase when you move in space, any more
than you will perceive a change in your location relative to yourself. ("No
matter where you go, there you are.") But an independent observer will see a
person who's moving at 100,000,000 meters per second in x,y,z and 283,000,000
meters per second in t. They see you moving in space, in the form of a
location change, and they also see you moving in time, in the form of a
disagreement between their perception of elapsed time and your own.
Likewise, if you spend all of your velocity allowance in (x,y,z), your t
component is necessarily zero. Among other inconvenient effects that occur at
dt/dt=0, you won't get any closer to your destination, even though your own
watch is still ticking normally. Particles moving near c experience this
effect from their point of view, even while we watch them smash into their
targets at unimaginable speeds.
This is special relativity in action. The insight behind general relativity is
twofold: 1) movement caused by the acceleration of gravity is
indistinguishable from movement caused by anything else; and 2) you don't even
have to move, just feel the acceleration. That second part was what really
baked peoples' noodles. It is what's responsible for the disagreement between
the two 5071As.
-- john, KE5FX
Miles Design LLC
> Hi Mike,
>
> The time rate does remain the same - at the device. The problem is the idea
> that it is the hyperfine transitions that determine the time...
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Re: [time-nuts] Einstein Special on PBS
Or, you could just stay at high elevation for a longer period of time and make the travel time less significant. -Chuck Harris Arthur Dent wrote: Tom wrote: "I'll make just a one word correction to your summary. The clocks run a bit faster not because of "the spinning earth" but because of "the earth"." You are correct, I misspoke. While that point may have been wrong I did check the elevation of Mount Sunapee and it is indeed at 2726 feet as measured by USGS and others. When I posted before I 'assumed' the researchers were from MIT or one of the Boston area schools (or UNH) and would therefore be at sea level. Rewatching the video they do say that the second clock is at sea level but they don't mention where they are. The drive up to the base of the mountain would probably be 1 to 1.5 hours so the 1st clock didn't go from sea level to 2726 feet instantaneously so during that travel time it was probably at an average of about 500' which is near the average elevation in New Hampshire. If the experiment had been conducted in the Burj Khalifa in Dubai, United Arab Emirates and the elevator could go from sea level to about 2000 feet, which may be the top floor, the experiment might be more exact because you'd eliminate the travel time. -Arthur ___ 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] Einstein Special on PBS
Tom wrote: "I'll make just a one word correction to your summary. The clocks run a bit faster not because of "the spinning earth" but because of "the earth"." You are correct, I misspoke. While that point may have been wrong I did check the elevation of Mount Sunapee and it is indeed at 2726 feet as measured by USGS and others. When I posted before I 'assumed' the researchers were from MIT or one of the Boston area schools (or UNH) and would therefore be at sea level. Rewatching the video they do say that the second clock is at sea level but they don't mention where they are. The drive up to the base of the mountain would probably be 1 to 1.5 hours so the 1st clock didn't go from sea level to 2726 feet instantaneously so during that travel time it was probably at an average of about 500' which is near the average elevation in New Hampshire. If the experiment had been conducted in the Burj Khalifa in Dubai, United Arab Emirates and the elevator could go from sea level to about 2000 feet, which may be the top floor, the experiment might be more exact because you'd eliminate the travel time. -Arthur ___ 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.
Re: [time-nuts] Einstein Special on PBS
A lot of BBC Horizon episodes are broadcast in the states as Nova, and visa versa. (Often with different narrators and sometimes localized content.) So it's possible this one will make it to the other side of the pond too. I'm pretty sure the bulk of this one was filmed by WGBH (choice of Microsemi formely Symmetricom in NH and New Hampshire mountain). Tim N3QE On Friday, November 27, 2015, Mr Smiley via time-nuts wrote: > Here in the UK, regarding the link below, I get > > " Were Sorry but this video is not available in your region due to right > restrictions" > > So much for science being universal. > > > > On 27/11/15 14:55, Tom Van Baak wrote: > >> Thanks, Joe. I thought it was well done. Note the show (length 53:07) is >> also online: >> >> http://www.pbs.org/wgbh/nova/physics/inside-einsteins-mind.html >> "Inside Einstein's Mind - Retrace the thought experiments that inspired >> his theory on the nature of reality." >> >> If you want to skip ahead past the historical acting and modern talking >> head stuff, the 5071A experiment runs from 39:11 to 40:54. >> >> I'll contact Microsemi and find out how much was real and how much was >> staged. I mention this because Discovery channel contacted me a few years >> ago about my Mt Rainier 5071A experiment and when they wanted me to fudge >> things for their camera people I told them I wasn't interested. >> >> /tvb >> >> - Original Message - >> From: "Joe Leikhim" >> To: >> Sent: Thursday, November 26, 2015 6:35 PM >> Subject: [time-nuts] Einstein Special on PBS >> >> >> There is a great special about Einstein on PBS. I think there are two >>> episodes. I watched one, near the end there was some definite >>> time-nuttery going on with portable HP cesium clocks >>> >>> -- >>> Joe Leikhim >>> >> ___ >> 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.
Re: [time-nuts] Einstein Special on PBS
So, here's how I finally grokked this stuff. c, the speed of light in a
vacuum, is often spoken of as a "speed limit" that nothing can ever exceed.
That's a bad way to put it, and people who have expressed it that way in
popular science writing for 100 years should feel bad.
Instead, the way to visualize relativity is to realize that c is the *only*
speed at which anything can travel. You are always moving at 300,000,000
meters per second, whether you want to or not. But you're doing it through all
four dimensions including time. If you choose to remain stationary in (x,y,z),
then all of your velocity is in the t direction. If you move through space at
100,000,000 meters per second in space, then your velocity in the t direction
is 283,000,000 meters per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)
It doesn't make sense to speak of moving a certain number of "meters" through
time, so your location in time itself is what has to change. You won't
perceive any drift in your personal timebase when you move in space, any more
than you will perceive a change in your location relative to yourself. ("No
matter where you go, there you are.") But an independent observer will see a
person who's moving at 100,000,000 meters per second in x,y,z and 283,000,000
meters per second in t. They see you moving in space, in the form of a
location change, and they also see you moving in time, in the form of a
disagreement between their perception of elapsed time and your own.
Likewise, if you spend all of your velocity allowance in (x,y,z), your t
component is necessarily zero. Among other inconvenient effects that occur at
dt/dt=0, you won't get any closer to your destination, even though your own
watch is still ticking normally. Particles moving near c experience this
effect from their point of view, even while we watch them smash into their
targets at unimaginable speeds.
This is special relativity in action. The insight behind general relativity is
twofold: 1) movement caused by the acceleration of gravity is
indistinguishable from movement caused by anything else; and 2) you don't even
have to move, just feel the acceleration. That second part was what really
baked peoples' noodles. It is what's responsible for the disagreement between
the two 5071As.
-- john, KE5FX
Miles Design LLC
> Hi Mike,
>
> The time rate does remain the same - at the device. The problem is the idea
> that it is the hyperfine transitions that determine the time...
___
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and follow the instructions there.
Re: [time-nuts] Einstein Special on PBS
Hi Tom - It has been a while. Well, I guess I am not in bad company if you struggled with this as well. I also like your take on it and will think some more, but it helped. So, if frequency remains the same, then d(phi)/d(t) ratio remains the same and both phase and time must change. Also, the concept that the number of transitions as a function of elevation (gravity) makes very good sense and of course would explain my dilemma. However, I am sure there is still something I am missing. Thanks & Regards - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak Sent: Friday, November 27, 2015 1:18 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Einstein Special on PBS Hi Mike, It's a good question and I've wrestled with it too. I see two choices: 1) Time is stable and every ultra-precise timing measurement of atomic behavior appears to depend on gravity. 2) Every ultra-precise timing measurement of atomic behavior is stable, and Time appears to depend on gravity. My impression is they are both equivalent and indistinguishable. Practical people like to use #1, for example, the SI second is defined as 9,192,631,770 Hz specifically and only at mean sea level on planet earth; national laboratories, and some time nuts, correct their clocks for elevation. By contrast, astronomers and physicists use #2 because it make everything simpler and universal. So you can say that a cesium clock ticks at 9,192,631,770 Hz +/- some function of gravity and velocity, or you can say that a cesium clock always ticks at 9,192,631,770 Hz in its "own reference frame". But either way, if you leave a clock on a mountain for a while, it comes back the same frequency it left. So what we measure is not the frequency, but the time (clock phase). The time the clock displays contains the sum total history of all frequency changes during the trip. You can't tell this during the trip, since the clock always thinks it is running at a constant and correct rate, wherever it is. /tvb - Original Message - From: "Mike Feher" To: "'Discussion of precise time and frequency measurement'" Sent: Friday, November 27, 2015 7:37 AM Subject: Re: [time-nuts] Einstein Special on PBS >I just do not get it. I know that now I am 70 and my good smart days are >behind me, but, this should be simple. In all these clocks mentioned, time is >derived from the transition of a hyperfine line of a certain atom within some >element, in this case cesium, In order for any of these clocks to deviate in >relative time at different heights for example, it seems to me that the period >of the hyperfine transitions must change as well, to make the defined second >longer or shorter. So, in these examples the elevation does not change the >time, but the way the atoms behave. What obvious item am I missing, besides >maybe brain capacity? Thanks - Mike > > Mike B. Feher, EOZ Inc. > 89 Arnold Blvd. > Howell, NJ, 07731 > 732-886-5960 office > 908-902-3831 cell > > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa > Sent: Friday, November 27, 2015 9:19 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Einstein Special on PBS > > Would've been more fun to see Tom and his kids going to the top of Mt Ranier > in 2005 with the ensemble :-). http://leapsecond.com/great2005/ > > They mentioned some "6 miles per day" offset due to GPS relativity effects. > I think this is the sum of both special relativity (time dilation) and > general relativity (gravitational) effects. The GR correction is 45 > microseconds a day fast; the SR correction is 7 microseconds slow. 38 > microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While > time drifts 38 microseconds a day, I'm not sure that GPS coordinates would > drift that fast - aren't most of the corrections in the same direction? > > Seeing Kip Thorne describe black holes was a blast - he refused to use the > word mass when describing them, just like when I took a course from him in > 1990. When my advisor taught the same course, I pleaded with him, "please use > coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my > brain does not work that way!!! I would've failed the course if it was only > GR; fortunately it also had plasma physics in the same quarter, and I was an > ace at that due to some undergraduate work.) > > Tim N3QE > > On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent > wrote: > >> In the special it looks lik
Re: [time-nuts] Einstein Special on PBS
Hi Mike, It's a good question and I've wrestled with it too. I see two choices: 1) Time is stable and every ultra-precise timing measurement of atomic behavior appears to depend on gravity. 2) Every ultra-precise timing measurement of atomic behavior is stable, and Time appears to depend on gravity. My impression is they are both equivalent and indistinguishable. Practical people like to use #1, for example, the SI second is defined as 9,192,631,770 Hz specifically and only at mean sea level on planet earth; national laboratories, and some time nuts, correct their clocks for elevation. By contrast, astronomers and physicists use #2 because it make everything simpler and universal. So you can say that a cesium clock ticks at 9,192,631,770 Hz +/- some function of gravity and velocity, or you can say that a cesium clock always ticks at 9,192,631,770 Hz in its "own reference frame". But either way, if you leave a clock on a mountain for a while, it comes back the same frequency it left. So what we measure is not the frequency, but the time (clock phase). The time the clock displays contains the sum total history of all frequency changes during the trip. You can't tell this during the trip, since the clock always thinks it is running at a constant and correct rate, wherever it is. /tvb - Original Message - From: "Mike Feher" To: "'Discussion of precise time and frequency measurement'" Sent: Friday, November 27, 2015 7:37 AM Subject: Re: [time-nuts] Einstein Special on PBS >I just do not get it. I know that now I am 70 and my good smart days are >behind me, but, this should be simple. In all these clocks mentioned, time is >derived from the transition of a hyperfine line of a certain atom within some >element, in this case cesium, In order for any of these clocks to deviate in >relative time at different heights for example, it seems to me that the period >of the hyperfine transitions must change as well, to make the defined second >longer or shorter. So, in these examples the elevation does not change the >time, but the way the atoms behave. What obvious item am I missing, besides >maybe brain capacity? Thanks - Mike > > Mike B. Feher, EOZ Inc. > 89 Arnold Blvd. > Howell, NJ, 07731 > 732-886-5960 office > 908-902-3831 cell > > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa > Sent: Friday, November 27, 2015 9:19 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Einstein Special on PBS > > Would've been more fun to see Tom and his kids going to the top of Mt Ranier > in 2005 with the ensemble :-). http://leapsecond.com/great2005/ > > They mentioned some "6 miles per day" offset due to GPS relativity effects. > I think this is the sum of both special relativity (time dilation) and > general relativity (gravitational) effects. The GR correction is 45 > microseconds a day fast; the SR correction is 7 microseconds slow. 38 > microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While > time drifts 38 microseconds a day, I'm not sure that GPS coordinates would > drift that fast - aren't most of the corrections in the same direction? > > Seeing Kip Thorne describe black holes was a blast - he refused to use the > word mass when describing them, just like when I took a course from him in > 1990. When my advisor taught the same course, I pleaded with him, "please use > coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my > brain does not work that way!!! I would've failed the course if it was only > GR; fortunately it also had plasma physics in the same quarter, and I was an > ace at that due to some undergraduate work.) > > Tim N3QE > > On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent > wrote: > >> In the special it looks like they used two HP5071A standards, an >> SRS620 counter, and a scope. They first made sure the stds were in >> sync then took one to the building at the top of the ski lift on New >> Hampshire's Mount Sunapee at 2726' elevation for 4 days where it would >> be running a little faster because it would be slightly further from >> the center of the spinning earth. After bringing the 5071A back from >> the top of the mountain they checked the difference in the start of >> square waves displayed on the scope and detected the 5071A at altitude >> was now 20ns ahead of the 5071A kept at sea level, as predicted, if I >> understood everything correctly. They explained that the clocks in the >> GPS satellites traveling at a much higher speed had to correct for the >> speed difference which als
Re: [time-nuts] Einstein Special on PBS
Hi Mike, The time rate does remain the same - at the device. The problem is the idea that it is the hyperfine transitions that determine the time. They are only a measurement of the time in that environment. So, if the rate of time is different at two locations, you will never see it *at* either location, because the clocks will run at the proper speed in either location; even though the rates are actually different between the two locations. Since you are actually *at* that location, you can't tell that time runs at a different rate. It is only by comparing the clocks in two different locations that you can determine the difference in space-time between these two locations. If you are falling into a black hole, your watch will not appear to slow down to you. You will still experience time as if you were sitting on your doorstep at home. (Ignoring the effects of spaghettification, or course.) But generations of people back on earth would live and die for each tick of your watch. Bob From: Mike Feher To: 'Bob Stewart' ; 'Discussion of precise time and frequency measurement' Sent: Friday, November 27, 2015 12:10 PM Subject: RE: [time-nuts] Einstein Special on PBS Bob - Thanks for attempting to make me see the light. But, I still do not. You said it yourself that hyperfine transitions remain the same. Since "time" on these device are derived from these transitions, they should also remain the same. I agree, from a relativistic point of vie the time will be different. I am just not convinced that using these types of clocks will demonstrate that. Thanks - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell ___ 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.
Re: [time-nuts] Einstein Special on PBS
Bob - Thanks for attempting to make me see the light. But, I still do not. You said it yourself that hyperfine transitions remain the same. Since "time" on these device are derived from these transitions, they should also remain the same. I agree, from a relativistic point of vie the time will be different. I am just not convinced that using these types of clocks will demonstrate that. Thanks - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Stewart Sent: Friday, November 27, 2015 12:48 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Einstein Special on PBS Hi Mike, I'm far from an expert on this, but what you're missing is that time and space isn't the same between any two points that are located in different gravity gradients and/or moving at different relative velocities. The hyperfine transitions are happening at the same local rate whether the Cs device is on planet earth, in orbit around the earth, or in close proximity to the sun or even a black hole. But, all of these examples are happening in different space-time environments (i.e. different local frames), so that "relative" to each other, they are experiencing time at different rates. It might help to think of it in terms of doppler effect, though this is not an exact comparison. But, if you have two clocks that are moving away from each other, they may very well be precisely synchronous, but because of the doppler effect, any measurement you make will show them to be running at different rates. Because of the effects of gravity, watches at different altitudes appear to run at different rates to the outsider, although to the person wearing the watch, nothing has actually changed; it is the other person's watch that is acting funny. So, essentially, a clock sitting on the ground at sea level is running in a very slightly different space time than one that is sitting on a mountain. And when you place a clock in orbit, you also have 14,000 odd MPH of velocity that's also having an impact on the space-time of that object. As a result, when you bring the prodigal clock back to sea level, it will have experienced a slightly different amount of time than the one at sea level. Note that the prodigal clock hasn't run at a different rate. It has actually experienced time running at a different rate from that of the clock on the ground. Bob From: Mike Feher To: 'Discussion of precise time and frequency measurement' Sent: Friday, November 27, 2015 9:37 AM Subject: Re: [time-nuts] Einstein Special on PBS I just do not get it. I know that now I am 70 and my good smart days are behind me, but, this should be simple. In all these clocks mentioned, time is derived from the transition of a hyperfine line of a certain atom within some element, in this case cesium, In order for any of these clocks to deviate in relative time at different heights for example, it seems to me that the period of the hyperfine transitions must change as well, to make the defined second longer or shorter. So, in these examples the elevation does not change the time, but the way the atoms behave. What obvious item am I missing, besides maybe brain capacity? Thanks - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa Sent: Friday, November 27, 2015 9:19 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Einstein Special on PBS Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 2005 with the ensemble :-). http://leapsecond.com/great2005/ They mentioned some "6 miles per day" offset due to GPS relativity effects. I think this is the sum of both special relativity (time dilation) and general relativity (gravitational) effects. The GR correction is 45 microseconds a day fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a day, I'm not sure that GPS coordinates would drift that fast - aren't most of the corrections in the same direction? Seeing Kip Thorne describe black holes was a blast - he refused to use the word mass when describing them, just like when I took a course from him in 1990. When my advisor taught the same course, I pleaded with him, "please use coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my brain does not work that way!!! I would've failed the course if it was only GR; fortunately it also had plasma physics in the same quarter, and I was an ace at that due to some underg
Re: [time-nuts] Einstein Special on PBS
Here in the UK, regarding the link below, I get " Were Sorry but this video is not available in your region due to right restrictions" So much for science being universal. On 27/11/15 14:55, Tom Van Baak wrote: Thanks, Joe. I thought it was well done. Note the show (length 53:07) is also online: http://www.pbs.org/wgbh/nova/physics/inside-einsteins-mind.html "Inside Einstein's Mind - Retrace the thought experiments that inspired his theory on the nature of reality." If you want to skip ahead past the historical acting and modern talking head stuff, the 5071A experiment runs from 39:11 to 40:54. I'll contact Microsemi and find out how much was real and how much was staged. I mention this because Discovery channel contacted me a few years ago about my Mt Rainier 5071A experiment and when they wanted me to fudge things for their camera people I told them I wasn't interested. /tvb - Original Message - From: "Joe Leikhim" To: Sent: Thursday, November 26, 2015 6:35 PM Subject: [time-nuts] Einstein Special on PBS There is a great special about Einstein on PBS. I think there are two episodes. I watched one, near the end there was some definite time-nuttery going on with portable HP cesium clocks -- Joe Leikhim ___ 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.
Re: [time-nuts] Einstein Special on PBS
Hi Mike, I'm far from an expert on this, but what you're missing is that time and space isn't the same between any two points that are located in different gravity gradients and/or moving at different relative velocities. The hyperfine transitions are happening at the same local rate whether the Cs device is on planet earth, in orbit around the earth, or in close proximity to the sun or even a black hole. But, all of these examples are happening in different space-time environments (i.e. different local frames), so that "relative" to each other, they are experiencing time at different rates. It might help to think of it in terms of doppler effect, though this is not an exact comparison. But, if you have two clocks that are moving away from each other, they may very well be precisely synchronous, but because of the doppler effect, any measurement you make will show them to be running at different rates. Because of the effects of gravity, watches at different altitudes appear to run at different rates to the outsider, although to the person wearing the watch, nothing has actually changed; it is the other person's watch that is acting funny. So, essentially, a clock sitting on the ground at sea level is running in a very slightly different space time than one that is sitting on a mountain. And when you place a clock in orbit, you also have 14,000 odd MPH of velocity that's also having an impact on the space-time of that object. As a result, when you bring the prodigal clock back to sea level, it will have experienced a slightly different amount of time than the one at sea level. Note that the prodigal clock hasn't run at a different rate. It has actually experienced time running at a different rate from that of the clock on the ground. Bob From: Mike Feher To: 'Discussion of precise time and frequency measurement' Sent: Friday, November 27, 2015 9:37 AM Subject: Re: [time-nuts] Einstein Special on PBS I just do not get it. I know that now I am 70 and my good smart days are behind me, but, this should be simple. In all these clocks mentioned, time is derived from the transition of a hyperfine line of a certain atom within some element, in this case cesium, In order for any of these clocks to deviate in relative time at different heights for example, it seems to me that the period of the hyperfine transitions must change as well, to make the defined second longer or shorter. So, in these examples the elevation does not change the time, but the way the atoms behave. What obvious item am I missing, besides maybe brain capacity? Thanks - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa Sent: Friday, November 27, 2015 9:19 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Einstein Special on PBS Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 2005 with the ensemble :-). http://leapsecond.com/great2005/ They mentioned some "6 miles per day" offset due to GPS relativity effects. I think this is the sum of both special relativity (time dilation) and general relativity (gravitational) effects. The GR correction is 45 microseconds a day fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a day, I'm not sure that GPS coordinates would drift that fast - aren't most of the corrections in the same direction? Seeing Kip Thorne describe black holes was a blast - he refused to use the word mass when describing them, just like when I took a course from him in 1990. When my advisor taught the same course, I pleaded with him, "please use coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my brain does not work that way!!! I would've failed the course if it was only GR; fortunately it also had plasma physics in the same quarter, and I was an ace at that due to some undergraduate work.) Tim N3QE On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent wrote: > In the special it looks like they used two HP5071A standards, an > SRS620 counter, and a scope. They first made sure the stds were in > sync then took one to the building at the top of the ski lift on New > Hampshire's Mount Sunapee at 2726' elevation for 4 days where it would > be running a little faster because it would be slightly further from > the center of the spinning earth. After bringing the 5071A back from > the top of the mountain they checked the difference in the start of > square waves displayed on the scope and detected the 5071A at altitude > was now 20ns ahead of the 5071A kept at sea level, as predicted, if I >
Re: [time-nuts] Einstein Special on PBS
Hi Arthur, That's a good summary. I'm glad you got to visit the mountain. Did you happen to check the elevation? Are there lodges along the road on the way up? I ask because at 2726 feet a clock will run 9.0e-14 fast (compared with sea level), which is 7.8 ns/day, or 31 ns over 4 days. But they measured 20 ns. So either they didn't stay close to 4 days, or they didn't stay close to the summit or maybe their clock rate was off or they didn't use a high-perf 5071A, or something. I'll make just a one word correction to your summary. The clocks run a bit faster not because of "the spinning earth" but because of "the earth". In other words, the clocks are experiencing a gravitational effect not a velocity effect. Gravity is a tiny bit less as you rise in elevation and this is what the clocks experience. Presumably the experiment would work fine even if the earth did not spin at all, or spun backwards. What's confusing is that in articles about relativity and shows like this, they talk about speed and trains and light and stuff (SR, special relativity) and so people are pre-disposed to be thinking in those terms. Worse yet, we know outer points of spinning objects have greater tangential speed than inner points so again people think of speed. There's mention of satellites, also high speed. But the main thing that is affecting the clocks at home vs. mountain is simply gravity. With a stationary clock at home and a stationary clock on the mountain, there's no velocity to talk about. The situation with airplanes and rockets and satellites is different; in these cases there is a large and combined gravitational and velocity effect. /tvb > In the special it looks like they used two HP5071A standards, an > SRS620 counter, and a scope. They first made sure the stds were > in sync then took one to the building at the top of the ski lift > on New Hampshire's Mount Sunapee at 2726' elevation for 4 days > where it would be running a little faster because it would be > slightly further from the center of the spinning earth. After > bringing the 5071A back from the top of the mountain they checked > the difference in the start of square waves displayed on the scope > and detected the 5071A at altitude was now 20ns ahead of the > 5071A kept at sea level, as predicted, if I understood everything > correctly. They explained that the clocks in the GPS satellites > traveling at a much higher speed had to correct for the speed > difference which also verified Einstein's theory. > > My wife and I were on the top of Mt. Sunapee this summer where we > enjoyed the views but didn't run any experiments. ;-) > > -Arthur ___ 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.
Re: [time-nuts] Einstein Special on PBS
> They mentioned some "6 miles per day" offset due to GPS relativity effects. > I think this is the sum of both special relativity (time dilation) and > general relativity (gravitational) effects. The GR correction is 45 > microseconds a day fast; the SR correction is 7 microseconds slow. 38 > microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While > time drifts 38 microseconds a day, I'm not sure that GPS coordinates would > drift that fast - aren't most of the corrections in the same direction? Hi Tim, Correct. Here's from the "rel" program (in my http://leapsecond.com/tools/ folder): C:\tvb\NPR>rel 2km 14000kph ** Altitude 2000.000 m (65616797.900 ft, 12427.424 mi) 5.274e-010 blueshift 1898630.424377 ps/hour 45567.130185 ns/day ** Velocity 3888.889 m/s (14000.000 km/h, 8699.197 mph) -8.414e-011 redshift -302888.070815 ps/hour -7269.313700 ns/day ** Net effect (GR+SR) 4.433e-010 shift 1595742.353562 ps/hour 38297.816485 ns/day What this means is that as a *source of UTC*, GPS would in fact be off by 38 us per day if you forgot about relativity when you designed it. But, you're right, you cannot blindly turn that "38 us/day" into "11 km/day". As long as *all* the GPS clocks are running too fast or too slow and as long as the receivers know what that offset is, the navigation system would still work just fine, relativity or not. This is true for any sort of triangulation (actually, trilateration) system. GPS is a PNT (Position, Navigation, and Timing) system. So while GPS is really cool, and relativity is really cool, the navigation part of GPS does not "depend" on relativity, per-se. /tvb ___ 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.
Re: [time-nuts] Einstein Special on PBS
I just do not get it. I know that now I am 70 and my good smart days are behind me, but, this should be simple. In all these clocks mentioned, time is derived from the transition of a hyperfine line of a certain atom within some element, in this case cesium, In order for any of these clocks to deviate in relative time at different heights for example, it seems to me that the period of the hyperfine transitions must change as well, to make the defined second longer or shorter. So, in these examples the elevation does not change the time, but the way the atoms behave. What obvious item am I missing, besides maybe brain capacity? Thanks - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Shoppa Sent: Friday, November 27, 2015 9:19 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Einstein Special on PBS Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 2005 with the ensemble :-). http://leapsecond.com/great2005/ They mentioned some "6 miles per day" offset due to GPS relativity effects. I think this is the sum of both special relativity (time dilation) and general relativity (gravitational) effects. The GR correction is 45 microseconds a day fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a day, I'm not sure that GPS coordinates would drift that fast - aren't most of the corrections in the same direction? Seeing Kip Thorne describe black holes was a blast - he refused to use the word mass when describing them, just like when I took a course from him in 1990. When my advisor taught the same course, I pleaded with him, "please use coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my brain does not work that way!!! I would've failed the course if it was only GR; fortunately it also had plasma physics in the same quarter, and I was an ace at that due to some undergraduate work.) Tim N3QE On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent wrote: > In the special it looks like they used two HP5071A standards, an > SRS620 counter, and a scope. They first made sure the stds were in > sync then took one to the building at the top of the ski lift on New > Hampshire's Mount Sunapee at 2726' elevation for 4 days where it would > be running a little faster because it would be slightly further from > the center of the spinning earth. After bringing the 5071A back from > the top of the mountain they checked the difference in the start of > square waves displayed on the scope and detected the 5071A at altitude > was now 20ns ahead of the 5071A kept at sea level, as predicted, if I > understood everything correctly. They explained that the clocks in the > GPS satellites traveling at a much higher speed had to correct for the > speed difference which also verified Einstein's theory. > > My wife and I were on the top of Mt. Sunapee this summer where we > enjoyed the views but didn't run any experiments. ;-) > > -Arthur > ___ > 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.
Re: [time-nuts] Einstein Special on PBS
Would've been more fun to see Tom and his kids going to the top of Mt Ranier in 2005 with the ensemble :-). http://leapsecond.com/great2005/ They mentioned some "6 miles per day" offset due to GPS relativity effects. I think this is the sum of both special relativity (time dilation) and general relativity (gravitational) effects. The GR correction is 45 microseconds a day fast; the SR correction is 7 microseconds slow. 38 microseconds seconds is 11 kilometers which is indeed 6 or 7 miles. While time drifts 38 microseconds a day, I'm not sure that GPS coordinates would drift that fast - aren't most of the corrections in the same direction? Seeing Kip Thorne describe black holes was a blast - he refused to use the word mass when describing them, just like when I took a course from him in 1990. When my advisor taught the same course, I pleaded with him, "please use coordinates!". (Kip Thorne loves coordinate-free notation, unfortunately my brain does not work that way!!! I would've failed the course if it was only GR; fortunately it also had plasma physics in the same quarter, and I was an ace at that due to some undergraduate work.) Tim N3QE On Fri, Nov 27, 2015 at 12:05 AM, Arthur Dent wrote: > In the special it looks like they used two HP5071A standards, an > SRS620 counter, and a scope. They first made sure the stds were > in sync then took one to the building at the top of the ski lift > on New Hampshire's Mount Sunapee at 2726' elevation for 4 days > where it would be running a little faster because it would be > slightly further from the center of the spinning earth. After > bringing the 5071A back from the top of the mountain they checked > the difference in the start of square waves displayed on the scope > and detected the 5071A at altitude was now 20ns ahead of the > 5071A kept at sea level, as predicted, if I understood everything > correctly. They explained that the clocks in the GPS satellites > traveling at a much higher speed had to correct for the speed > difference which also verified Einstein's theory. > > My wife and I were on the top of Mt. Sunapee this summer where we > enjoyed the views but didn't run any experiments. ;-) > > -Arthur > ___ > 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.
Re: [time-nuts] Einstein Special on PBS
Thanks, Joe. I thought it was well done. Note the show (length 53:07) is also online: http://www.pbs.org/wgbh/nova/physics/inside-einsteins-mind.html "Inside Einstein's Mind - Retrace the thought experiments that inspired his theory on the nature of reality." If you want to skip ahead past the historical acting and modern talking head stuff, the 5071A experiment runs from 39:11 to 40:54. I'll contact Microsemi and find out how much was real and how much was staged. I mention this because Discovery channel contacted me a few years ago about my Mt Rainier 5071A experiment and when they wanted me to fudge things for their camera people I told them I wasn't interested. /tvb - Original Message - From: "Joe Leikhim" To: Sent: Thursday, November 26, 2015 6:35 PM Subject: [time-nuts] Einstein Special on PBS > There is a great special about Einstein on PBS. I think there are two > episodes. I watched one, near the end there was some definite > time-nuttery going on with portable HP cesium clocks > > -- > Joe Leikhim ___ 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] Einstein Special on PBS
In the special it looks like they used two HP5071A standards, an SRS620 counter, and a scope. They first made sure the stds were in sync then took one to the building at the top of the ski lift on New Hampshire's Mount Sunapee at 2726' elevation for 4 days where it would be running a little faster because it would be slightly further from the center of the spinning earth. After bringing the 5071A back from the top of the mountain they checked the difference in the start of square waves displayed on the scope and detected the 5071A at altitude was now 20ns ahead of the 5071A kept at sea level, as predicted, if I understood everything correctly. They explained that the clocks in the GPS satellites traveling at a much higher speed had to correct for the speed difference which also verified Einstein's theory. My wife and I were on the top of Mt. Sunapee this summer where we enjoyed the views but didn't run any experiments. ;-) -Arthur ___ 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] Einstein Special on PBS
There is a great special about Einstein on PBS. I think there are two episodes. I watched one, near the end there was some definite time-nuttery going on with portable HP cesium clocks -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida jleik...@leikhim.com 407-982-0446 WWW.LEIKHIM.COM ___ 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.
