Re: [time-nuts] Q/noise of Earth as an oscillator

> Subject: Re: [time-nuts] Q/noise of Earth as an oscillator Hi Glenn, Your 15.04 number rings a bell [1]. The conventional solar day is simply 86400 seconds (24 hours). So each hour is 15 degrees, exactly. But the actual (sidereal) earth rotation rate is about 86164 SI seconds (23h 56m 4.09

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

net> To: "Tom Van Baak" <t...@leapsecond.com>; "Discussion of precise time and frequency measurement" <time-nuts@febo.com> 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

Re: [time-nuts] Q/noise of Earth as an oscillator

quot;Discussion of precise time and frequency measurement" <time-nuts@febo.com> 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.&quo

Re: [time-nuts] Q/noise of Earth as an oscillator

Message - From: "Jim Palfreyman" <jim77...@gmail.com> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> 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 ener

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

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 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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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 >

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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? --

Re: [time-nuts] Q/noise of Earth as an oscillator

of Jello. But you'd have to figure out how to really slam the planet to excite the entire volume. Earthquakes are probably too wimpy. Ron From: Chris Caudle <ch...@chriscaudle.org> To: time-nuts@febo.com Sent: Wednesday, July 27, 2016 8:50 AM Subject: Re: [time-nuts] Q/noise o

Re: [time-nuts] Q/noise of Earth as an oscillator

com/pages/Q/1927-Q-patent-600x300.gif > > /tvb > > - Original Message ----- > From: "Michael Wouters" <michaeljwout...@gmail.com> > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com>; <att...@kinali.ch> > Se

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

> 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

Re: [time-nuts] Q/noise of Earth as an oscillator

aturday, July 30, 2016 8:48 AM Subject: Re: [time-nuts] Q/noise of Earth as an oscillator 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/LaserG

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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, > >

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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 >

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

Chris Caudle <ch...@chriscaudle.org> > 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 cons

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

<ch...@chriscaudle.org> 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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

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 >>> 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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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.

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

gt; > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com>; <att...@kinali.ch> > Sent: Wednesday, July 27, 2016 5:43 AM > Subject: Re: [time-nuts] Q/noise of Earth as an oscillator > > >> On Wed, Jul 27, 2016 at 8:08 AM, A

Re: [time-nuts] Q/noise of Earth as an oscillator

s/Q/1927-Q-patent-600x300.gif /tvb - Original Message - From: "Michael Wouters" <michaeljwout...@gmail.com> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com>; <att...@kinali.ch> Sent: Wednesday, July 27, 2016 5

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

- Original message From: Brooke Clarke <bro...@pacific.net> Date: 27/07/2016 01:00 (GMT+01:00) To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] Q/noise of Earth as an oscillator Hi Hal: I resemble that remark. Mom

Re: [time-nuts] Q/noise of Earth as an oscillator

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,

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 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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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

Re: [time-nuts] Q/noise of Earth as an oscillator

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