Hi Jim.
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?
By first one, do you mean where does the initial energy come from?
For a pendulum clock, you supply energy with a lift or a push. For a lift to
the side, E = mgh, where h is the height above the base. For a push from
center, E = 1/2 mv^2. Either way, it takes all the potential or kinetic E you
provide and starts making time from there.
For a rotating clock, you just give it a twist. In this case, E = 1/2 Iw^2,
where I is the moment of inertia and w (omega) is angular velocity. For earth
the total E is 2.1e29 J. That's the energy number you want, yes?
Sure it was there at the start when the solar system formed, but where is it
now?
I don't have data on where the initial swirl of solar system mass came from, or
how much of that rotational energy went into our planet and its pesky moon, or
Who or what gave that initial twist. The Q is pretty high so I assume you could
work backwards, but I leave that to astronomers and cosmologists. I believe the
2 ms/day / century estimate we use is one such measurement.
For more on earth rotation rate, UTC and leap seconds see
https://www.ucolick.org/~sla/leapsecs/dutc.html
Surely in the literature there is a pile of information or speculation
regarding all the rotational energy in the universe. It seems a common theme
everywhere you look; maybe it was as much Big Twist as Big Bang? Perhaps in
your Pulsar research you've run across some papers you could share. Off-list is
ok, unless you think it has general time-nuts appeal. We're running the risk of
spinning off-topic already.
Thanks,
/tvb
----- Original Message -----
From: "Jim Palfreyman" <[email protected]>
To: "Discussion of precise time and frequency measurement" <[email protected]>
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 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 <[email protected]> wrote:
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 description versus energy loss.
Like joule heating (resistance, friction).
Notice that these are all energy losses over time; gradual processes with
perhaps an exponential time constant, but without cycles or periods. We
know not to apply Q in these scenarios.
But when you have an oscillator, or a resonator, or (as I suggest) a
"rotator", it seems to make sense to use Q to describe the normalized rate
of decay. So three keys to Q: you need energy; you need energy loss; you
need cycles over which that loss repeatedly occurs.
We use units of time (for example, SI seconds) when we describe a rate.
But here's why Q is unitless -- you normalize the energy (using E / dE)
*and* you also normalize the time (by cycle). No Joules. No seconds. So
having period is fundamental to Q. It's this unitless character of Q (in
both energy and time) that makes it portable from one branch of science to
another. And if you measure in radians you can even get rid of the 2*pi
factor ;-)
Without controversy, lots of articles define Q as 2*pi times {total
energy} / {energy lost per cycle}. To me, a slowly decaying spinning Earth
meets the three criteria. It appears to follow both the letter and the
spirit of Q.
Bob:
ummm…. Q is the general term of rate of energy loss and we just happen
to apply
it to oscillators in a very elegant fashion….
Oh, no. Now we have both quality factor and elegance factor!
/tvb
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----- Original Message -----
From: "Jim Palfreyman" <[email protected]>
To: "Discussion of precise time and frequency measurement" <[email protected]>
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 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 <[email protected]> wrote:
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 description versus energy loss.
Like joule heating (resistance, friction).
Notice that these are all energy losses over time; gradual processes with
perhaps an exponential time constant, but without cycles or periods. We
know not to apply Q in these scenarios.
But when you have an oscillator, or a resonator, or (as I suggest) a
"rotator", it seems to make sense to use Q to describe the normalized rate
of decay. So three keys to Q: you need energy; you need energy loss; you
need cycles over which that loss repeatedly occurs.
We use units of time (for example, SI seconds) when we describe a rate.
But here's why Q is unitless -- you normalize the energy (using E / dE)
*and* you also normalize the time (by cycle). No Joules. No seconds. So
having period is fundamental to Q. It's this unitless character of Q (in
both energy and time) that makes it portable from one branch of science to
another. And if you measure in radians you can even get rid of the 2*pi
factor ;-)
Without controversy, lots of articles define Q as 2*pi times {total
energy} / {energy lost per cycle}. To me, a slowly decaying spinning Earth
meets the three criteria. It appears to follow both the letter and the
spirit of Q.
Bob:
ummm…. Q is the general term of rate of energy loss and we just happen
to apply
it to oscillators in a very elegant fashion….
Oh, no. Now we have both quality factor and elegance factor!
/tvb
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
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and follow the instructions there.
