: "Tom Van Baak" ; "Discussion of precise time and
frequency measurement"
Sent: Monday, August 01, 2016 10:38 AM
Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
In navigation we used the earth rate of 15.04 degrees per hour.
This was treated as a 'constant' even th
glennmaill...@bellsouth.net said:
> In navigation we used the earth rate of 15.04 degrees per hour. This was
> treated as a 'constant' even though it varied with wind, waves on the ocean
> and other things affecting the instantaneous rotational speed of the earth.
Were the wind and waves and wh
ak" ; "Discussion of precise time and
frequency measurement"
Sent: Monday, August 01, 2016 10:38 AM
Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
In navigation we used the earth rate of 15.04 degrees per hour.
This was treated as a 'constant' even though it va
ussion of precise time and frequency measurement"
Sent: Sunday, July 31, 2016 7:34 PM
Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
Hi Tom,
You said: "you need energy; you need energy loss; you need cycles over
which that loss repeatedly occurs."
With regard to the
tvb
- Original Message -
From: "Jim Palfreyman"
To: "Discussion of precise time and frequency measurement"
Sent: Sunday, July 31, 2016 7:34 PM
Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
Hi Tom,
You said: "you need energy; you need energy loss; you ne
At the risk of boring everyone, here is an "Alice and Bob" thought
experiment concerning linear and circular movement:
Condition A: Let's say that Alice is in her spacecraft in inertial
straight line travel through nearly free space containing a thin gas
which creates a slight friction to movement
t...@radio.sent.com said:
> As I pointed out, what's the difference between an inertial body moving in a
> straight line and a rotating body?
The rotating body has a natural unit of time so there is a convenient way to
make Q dimensionless.
For linear motion, the natural unit of decay would be
I still claim that there is no natural frequency associated with the
rotation of a body. The periodic nature of the rotating body motion is
confusing you. The choice of a coordinate system is what is confusing.
As I pointed out, what's the difference between an inertial body moving
in a straight l
Hi Tom,
You said: "you need energy; you need energy loss; you need cycles over
which that loss repeatedly occurs."
With regard to the earth, where is the first one? Sure it was there at the
start when the solar system formed, but where is it now?
Jim
On 1 August 2016 at 12:16, Tom Van Baak wr
Hal:
> Is there a term other than Q that is used to describe the rate of energy loss
> for things that aren't oscillators?
Jim:
> cooling (as in hot things)
> discharge (as in capacitors and batteries)
> leakage (as in pressure vessels)
> loss
Scott:
> An irreversible process would be a better d
On Sat, Jul 30, 2016 at 1:19 AM, Tom Van Baak wrote:
> The remaining question in this thread is if earth Q measurement has actual
> meaning, that is, if the concept of Q is valid for a slowly decaying rotating
> object, as it is for a slowly decaying simple harmonic oscillator. And that's
> were
Hal Murray wrote:
> It's energy loss in both cases.
>
> Is there a term other than Q that is used to describe the rate of energy loss
> for things that aren't oscillators?
I've seen "energy dissipation" or "energy decrement".
Before Q was used to describe line width of atomic and optical clocks
Hi
> On Jul 31, 2016, at 8:19 PM, Hal Murray wrote:
>
>
> t...@radio.sent.com said:
>> So loss effects frequency in one situation and amplitude in the other. How
>> can Q relate to both situations?
>
> It's energy loss in both cases.
>
> Is there a term other than Q that is used to describe
An irreversible process would be a better description versus energy loss.
Like joule heating (resistance, friction).
On Sunday, 31 July 2016, Hal Murray wrote:
>
> t...@radio.sent.com said:
> > So loss effects frequency in one situation and amplitude in the other.
> How
> > can Q relate to both
On 7/31/16 5:19 PM, Hal Murray wrote:
t...@radio.sent.com said:
So loss effects frequency in one situation and amplitude in the other. How
can Q relate to both situations?
It's energy loss in both cases.
Is there a term other than Q that is used to describe the rate of energy loss
for things
t...@radio.sent.com said:
> So loss effects frequency in one situation and amplitude in the other. How
> can Q relate to both situations?
It's energy loss in both cases.
Is there a term other than Q that is used to describe the rate of energy loss
for things that aren't oscillators?
--
Thes
etc. Each of these modes have amplitude,
period, and decay. They all interact with each other and with the main swinging
of the pendulum in nasty ways. And yes, they all have their own Q.
/tvb
- Original Message -
From: "Ron Ott"
To: ; "Discussion of precise time and fr
aph in which Q appeared:
> http://leapsecond.com/pages/Q/1927-Q-patent-600x300.gif
>
> /tvb
>
> - Original Message -
> From: "Michael Wouters"
> To: "Discussion of precise time and frequency measurement"
> ;
> Sent: Wednesday, July 27, 2016 5:43 A
Thanks Tom, I would agree LIGOs efforts are beyond heroic, I will try to
find some of their phase noise plots.
Regarding Q of the earth, I would agree one could compute an UNloaded Q for
the earth as if it were a mass element in some form of a mechanical
oscillator. The first sticky point is which
> What about an ADEV/TDEV plot of the pulsar J0437-4715?
Very boring. It's a straight line from top left to bottom right. :-)
See page 5 of this: http://arxiv.org/pdf/1004.0115.pdf
Jim Palfreyman
On 29 July 2016 at 17:33, Azelio Boriani wrote:
> What about an ADEV/TDEV plot of the pulsar J04
the
2010/2011 quakes and cave access is not permitted.
DaveB,
Christchurch, NZ
- Original Message -
From: ""Björn Gabrielsson""
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, July 30, 2016 8:48 AM
Subject: Re: [tim
I'am not sure how the big ring lasers have progressed over the past
years. It seems the big New Zeeland earthquake messed up the nice ring
lasers over there.
http://www.fs.wettzell.de/LKREISEL/G/LaserGyros.html
http://www.phys.canterbury.ac.nz/ringlaser/about_us.shtml
--
Björn
> I believe
Scott Stobbe wrote:
> I believe a phase noise plot deep into the uHz or lower would apply to the
> rotation rate of the earth.
Yup. You'll see lots of uHz to Hz noise plots by people working with seismic
noise, for example. My introduction to the subject were the many plots and
papers that descr
the Q factor could be derived from the modulation bandwidth of an
oscillator [ the "old way" of measuring the Q of resonator of the
running oscillator's ], therefore if we look the fluctuation spectrum of
the frequency of an oscillator we could determine the Q. Any circular
movement could be se
I believe a phase noise plot deep into the uHz or lower would apply to the
rotation rate of the earth.
On Saturday, 23 July 2016, Hal Murray wrote:
>
> t...@leapsecond.com said:
> > Earth is a very noisy, wandering, drifting,
> incredibly-expensive-to-measure,
> > low-precision (though high-Q) c
On Fri, 29 Jul 2016 03:29:27 -0500
David wrote:
> Capacitors and inductors have an associated Q while lacking a resonate
> frequency except for parasitic elements. Their Q increases with
> frequency up to a point; does that apply to a spinning body? I guess
> it depends on the loss mechanism.
What about an ADEV/TDEV plot of the pulsar J0437-4715?
On Fri, Jul 29, 2016 at 12:39 AM, Jim Palfreyman wrote:
> Hi All,
>
> Tom gave me a nudge to look here - I hadn't been following this thread.
>
> For those that don't know, I study pulsars and so the way we measure what
> pulsars do could be
On Wed, 27 Jul 2016 15:15:48 -0400, you wrote:
>On 7/27/2016 10:04 AM, time-nuts-requ...@febo.com wrote:
>
>> Exciting the Earth with a new frequency (and an adeguate amount of
>> energy) sets a new rotational speed: you cannot retune a (for example)
>> quartz crystal in the same way...
>
>Sure yo
Hi All,
Tom gave me a nudge to look here - I hadn't been following this thread.
For those that don't know, I study pulsars and so the way we measure what
pulsars do could be relevant to this discussion.
First, I have never heard of a Q measure when referencing a pulsar. I think
the key here is t
time-nuts@febo.com
> Sent: Wednesday, July 27, 2016 8:50 AM
> Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
>
> On Wed, July 27, 2016 10:33 am, Chris Caudle wrote:
>> Does that imply that this value is not constant:
>>>> And if you take the classic definit
Neville Michie wrote:
> The conical pendulum has a simple form of a weight on a string, instead
> of oscillating in one plane as a conventional pendulum, it swings around
> in a circular orbit in the horizontal plane. It has a definite resonant
> frequency.
I don't think it does have a resonant
audle
To: time-nuts@febo.com
Sent: Wednesday, July 27, 2016 8:50 AM
Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
On Wed, July 27, 2016 10:33 am, Chris Caudle wrote:
> Does that imply that this value is not constant:
>>> And if you take the classic definition
>
in case the Earth, the circular frequency of the Earth is equal of a
sinusoidal wave's frequency, which is a projection of the Earth circular
movement in a plain, which is perpendicular to the axis of the Earth.
The Q of the Earth in interpreted as the quotient of the phase speed of
the Earth'
The discussion of Earth as a system with Q, but which is not resonant,
is a more extreme case than the CONICAL PENDULUM.
The conical pendulum has a simple form of a weight on a string, instead of
oscillating
in one plane as a conventional pendulum, it swings around in a circular orbit
in the h
On 7/27/2016 10:04 AM, time-nuts-requ...@febo.com wrote:
Exciting the Earth with a new frequency (and an adeguate amount of
energy) sets a new rotational speed: you cannot retune a (for example)
quartz crystal in the same way...
Sure you can. Spin it at 100 RPM, or 1000, RPM or even 25000 RPM
On Wed, Jul 27, 2016 at 11:33 AM, Chris Caudle
wrote:
> Who has a globe on magnetic bearings in a vacuum chamber and will run the
> experiment for us?
>
The superconducting gyroscopes in the Gravity Probe B satellite did an
extraordinary job of eliminating frictional and other losses in a spinni
On Wed, July 27, 2016 10:33 am, Chris Caudle wrote:
> Does that imply that this value is not constant:
>>> And if you take the classic definition
>>> Q = 2 pi * total energy /energy lost per cycle
>>> then it would seem earth has a Q factor.
After re-reading "The Story of Q" I agree that Q of a ro
On Wed, July 27, 2016 8:58 am, Azelio Boriani wrote:
> Exciting the Earth with a new frequency (and an adeguate amount of
> energy) sets a new rotational speed: you cannot retune a (for example)
> quartz crystal in the same way...
Does that imply that this value is not constant:
> On Wed, Jul 27,
If you consider viewing earth from above the equator at a long distance
and imagine a
spot on the surface of the earth. That spot will appear to have a
sinusoidal motion.
The frequency of the sinusoid exhibits a decay. That decay can be
considered as the Q
of the earths rotation.
Pete.
We have discussed quartz crystals which despite their high Q, may
suffer from periodic "jumps" in frequency do to what I assume are
imperfection that hardly affect Q. If they did affect Q, then that
would have been a good way to grade them for this behavior.
Temperature coefficient is also indepe
second.com/pages/Q/1927-US1628983.pdf
>
> or view the first paragraph in which Q appeared:
> http://leapsecond.com/pages/Q/1927-Q-patent-600x300.gif
>
> /tvb
>
> - Original Message -----
> From: "Michael Wouters"
> To: "Discussion of precise time and freque
/pages/Q/1927-Q-patent-600x300.gif
/tvb
- Original Message -
From: "Michael Wouters"
To: "Discussion of precise time and frequency measurement"
;
Sent: Wednesday, July 27, 2016 5:43 AM
Subject: Re: [time-nuts] Q/noise of Earth as an oscillator
> On Wed, Jul 27,
On 7/27/16 5:43 AM, Michael Wouters wrote:
On Wed, Jul 27, 2016 at 8:08 AM, Attila Kinali wrote:
"I am not sure you can apply this definition of Q onto earth."
It doesn't make sense to me either.
If you mark a point on the surface of a sphere then you can observe
that point as the sphere
rot
On Wed, Jul 27, 2016 at 8:08 AM, Attila Kinali wrote:
"I am not sure you can apply this definition of Q onto earth."
It doesn't make sense to me either.
If you mark a point on the surface of a sphere then you can observe
that point as the sphere
rotates and count rotations to make a clock. If
-- Original message From: Brooke Clarke
Date: 27/07/2016 01:00 (GMT+01:00) To: Discussion of
precise time and frequency measurement Subject: Re:
[time-nuts] Q/noise of Earth as an oscillator
Hi Hal:
I resemble that remark.
Momentum and drift. It's interesting that the drift
Around mid 1978 a scientific magazine had an item on the shift of axis
of the earth due to earthquakes. Sorry but searching has not found the
item. My, not to be relied on memory, thinks that it was from the
French Bureau International de l'Heure in Science or Scientific American
Cheers,
Wil
Hi Hal:
I resemble that remark.
Momentum and drift. It's interesting that the drift rate depends on the physical volume. See table at:
http://www.prc68.com/I/Sensors.shtml#Gyroscopic
http://www.prc68.com/I/Gyroscopes.html
--
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.end2party
Hal Murray wrote:
> I've seen mention that the rotation rate of the Earth changed by a few
> microseconds per day as a result of the 2011 earthquake in Japan. Does that
> show up in any data? Your recent graph doesn't go back that far and it's got
> a full scale of 2000 microseconds so a few
att...@kinali.ch said:
> I am not sure you can apply this definition of Q onto earth. Q is defined
> for harmonic oscillators (or oscillators that can be approximated by an
> harmonic oscillator) but the earth isn't oscillating, it's rotating. While,
> for time keeping purposes, similar in nature,
On Wed, 27 Jul 2016 00:08:47 +0200, you wrote:
>Hoi Tom,
>
>On Tue, 26 Jul 2016 12:36:37 -0700
>"Tom Van Baak" wrote:
>
>> Among other things, the quality-factor, or Q is a measure of how slowly a
>> free-running oscillator runs down. There are lots of examples of periodic or
>> damped oscillat
Hoi Tom,
On Tue, 26 Jul 2016 12:36:37 -0700
"Tom Van Baak" wrote:
> Among other things, the quality-factor, or Q is a measure of how slowly a
> free-running oscillator runs down. There are lots of examples of periodic or
> damped oscillatory motion that have Q -- RC or LC circuit, tuning fork,
Hal Murray wrote:
> What is the Q of the Earth? It might be on one of your web pages, but I
> don't remember seeing it. Google found a few mentions, but I didn't find a
> number.
3.1415 * 86400 * 365 * 100 / 0.002 = 5e12, or 5 trillion. Here's why:
(1)
Among other things, the quality-factor
42
On Sat, Jul 23, 2016 at 7:59 PM, Hal Murray wrote:
>
> t...@leapsecond.com said:
> > Earth is a very noisy, wandering, drifting,
> incredibly-expensive-to-measure,
> > low-precision (though high-Q) clock.
>
> What is the Q of the Earth? It might be on one of your web pages, but I
> don't rem
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