B What is a Clock? Syncing Technologies Explained

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  • #51
Mister T said:
It was part of your original question.

I said: How do we decide what is a clock and how do clocks that rely on different technologies stay synchronized?

The how was the interesting part for me.

russ_watters said:
the difference between today and 500 years ago is that we know and use the physics by which clocks operate to accurately predict their accuracy.

That was the discussion that I hoped for - the physics of clocks - how do clocks that rely of different principles stay synchronized? (or almost synchronized)

Most people who have chipped in here apply what you said in the beginning:

russ_watters said:
Physicists seem to use the circular definitions:
-Clocks are devices that tell time.
-Time is what a clock measures.
 
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  • #52
Torog said:
I said: How do we decide what is a clock and how do clocks that rely on different technologies stay synchronized?

The how was the interesting part for me.
That was the discussion that I hoped for - the physics of clocks - how do clocks that rely of different principles stay synchronized? (or almost synchronized)

Most people who have chipped in here apply what you said in the beginning:
I am sure a google search would mention which clock is referenced most often and how. Your point with "Decide on" is interesting if asking what time did they decided to set and why?

Gravity was one of the first ways I think and used for the longest.
 
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  • #53
Torog said:
How do we decide what is a clock and how do clocks that rely on different technologies stay synchronized?
I think we decide that something may be used as a clock if it seems to possesses rhythm or flow. Any crude clock rhythm can be checked to the second (during daylight) against a sufficiently large sundial where the shadow pointer moves in great enough increments to see to mark the correct division of seconds off in a 24 hour day. Note that Earth is an object that possesses more than one angular momentum and was thereby our first accurate timepiece.

All our clocks have this common denominator. They all rely on angular momentum, or a portion thereof , one way or another, to stay synchronized and count off rotations or portions thereof (pendulum). Two very different clocks, such as a pendulum and flywheel/hairspring, can be perfectly synchronized by having proportional mechanical ratios designed to some rhythmic multiple of a harmonic tick to the other, or at least achieving a repeating periodic momentary synchrony after a certain number of ticks (For the nearly smooth rotation of a planet, the ticks may have to reduce to Planck motions in a ridiculous micro-sense).

Since all clocks rely on angular momentum, all are likely sensitive to rotation; for instance any common flywheel/hairspring clock can be stopped by "rocking it" in a gradually decreasing opposing rhythm to the reciprocating flywheel direction. All other clocks are also likely sensitive to a rotational motion in a similar way, as it disturbs angular momentum. I have wondered, but not yet tested, if an old tick-tock pocket watch will keep the same time when placed face-up on a continuously rotating turntable.

A pendulum clock is sensitive to being level, to gravity and the length of it's pendulum. Whereas a flywheel/hairspring clock should run "relatively" slower on the surface of Earth than the moon (greater gravity on earth), a pendulum clock will run slower on the moon because the pendulum will "fall" slower in lower gravity (swing slower). A pendulum clock moved from sea level to 4,000 feet (1,200 m) will lose 16 seconds per day.

It is the hairspring adjustment on the reciprocating flywheel clock that determines it's fine time-rate adjustment. If left unadjusted from Earth setting, it should run faster on the moon, wear out and not live as long as it's identical twin on earth. If such a flywheel clock were large enough, we might be able to read it with a powerful telescope on earth. Barring other interference, it would at first automatically read behind 1.3 seconds just because we would see it in history, the time the picture of light takes to reach us. But then the wind-up moon-clock would very gradually catch up because it ran faster in 1/6th the gravity of Earth (We'd have to somehow wind it with Earth tide). And if time runs faster on the moon, has it affected the apparent rotation position of it's accumulated orbits around Earth over the millions of years. :wink:

Wes
EDIT: Earth tide wouldn't work. We'd have to use solar tide to wind the moon-watch mainspring.
 
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  • #54
Torog said:
I said: How do we decide what is a clock and how do clocks that rely on different technologies stay synchronized?

The how was the interesting part for me.

That was the discussion that I hoped for - the physics of clocks - how do clocks that rely of different principles stay synchronized? (or almost synchronized)
I think the “how” is simply calibration. E.g. we find that a pendulum of a given length cycles once for every 60,000 cycles of a given quartz oscillator. So we divide the quartz oscillator by a calibration factor of 1/60000, and then they “stay synchronized” as I think you intended it.
 
  • #55
Wes Tausend said:
All our clocks have this common denominator. They all rely on angular momentum,
Not all clocks involve rotation. What about water clocks? Candle clocks? Hourglasses? Quartz clocks? Atomic clocks? Carbon dating?

Even for those clocks that do involve oscillating rotation, it doesn't seem to me that "conservation of angular momentum" is the principle that makes them work.
 
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  • #56
Wes Tausend said:
All our clocks have this common denominator. They all rely on angular momentum, or a portion thereof , one way or another, to stay synchronized and count off rotations or portions thereof (pendulum).

You qualify the above with (pendulum). Isn't it possible that if you drill down into the mechanism of all clocks you will find Inertial mass somewhere in the regulating mechanism.

Thanks, this is what interests me, the how or physics of the regulating mechanisms of clocks.
 
  • #57
Torog said:
Thanks, this is what interests me, the how or physics of the regulating mechanisms of clocks
This has been answered already. If you feel that the answers received have not actually addressed your question then you need to rephrase. You are not communicating your question. People are answering what you are asking, so you need to change what you are asking not just repeat it again.

Did you not understand the previous answers or what else do you want?
 
  • #58
I do understand English. Most people in this thread talked about how to synchronise clocks - very little on the physics.

Cut me out if you wish.

Tired of being bullied by the powers on this forum.
 
  • #59
Torog said:
Isn't it possible that if you drill down into the mechanism of all clocks you will find Inertial mass somewhere in the regulating mechanism.

Atomic clocks are at least one counterexample.
 
  • #60
Torog said:
Most people in this thread talked about how to synchronise clocks

That's because you asked how clocks were kept synchronized in your OP.

Torog said:
very little on the physics

Plenty of posts have talked about possible physical mechanisms for clocks. But the question you asked in your OP wasn't about specific physical mechanisms, it was a general question about how we can tell that any physical mechanism is a "clock". That question has been answered.

Torog said:
the how or physics of the regulating mechanisms of clocks

If you are looking for some single physical principle, like "inertial mass", that appears in all clocks, there isn't one.
 
  • #61
Torog said:
I do understand English. Most people in this thread talked about how to synchronise clocks - very little on the physics.

Cut me out if you wish.

Tired of being bullied by the powers on this forum.
Wow. I was asking for you to describe what you want better. I have no idea how asking for clarification is bullying.

You are getting answers, but you do not seem satisfied with the answers. So I am asking you to help get you the answers by refining the question.

You keep saying “the how” and I thought I had answered “the how” but you didn’t think it was satisfactory. So we need you to be more communicative about your question. (The opposite of cutting you out)
 
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  • #62
@Torog It is also worth noting that you may have been led astray by some incorrect posts(some now deled) from another poster. The only thing even close to aggressive/negative I've seen here were responses to that poster, not to you. You're doing fine, even if that caused some issues; not your fault.
 
  • #63
Torog said:
Most people in this thread talked about how to synchronise clocks - very little on the physics.

Synchronizing two co-located clocks is trivial, you originally asked about how they are kept synchronized. The former is an issue of accuracy while the latter is an issue of precision. There really is no physical mechanism at work in the background that keeps clocks synchronized. In fact, no two clocks ever stay perfectly synchronized, there is always some drift, or to put it in technical terms, imprecision.

The science of metrology is all about improving the precision, but there is no way to make it perfect. Like any machinist will tell you, regardless of how precise the machining, there is always some level of tolerance (or imprecision) that's considered acceptable for the purpose at hand.
 
  • #64
PeterDonis said:
Atomic clocks are at least one counterexample.

I got this from: http://hyperphysics.phy-astr.gsu.edu/hbase/Nuclear/nspin.html

“nuclei often act as if they are a single entity with intrinsic angular momentum I. Associated with each nuclear spin is a nuclear magnetic moment which produces magnetic interactions with its environment.”​

As I understand (& I am winging it here) the frequency developed by the nucleus of the cesium 131 used in the resonators of atomic clocks is based on the following:

From: https://quantummechanics.ucsd.edu/ph130a/130_notes/node357.html
“Hyperfine Structure
The interaction between the magnetic moment, due to the spin of the nucleus, and the larger magnetic moment, due to the electron's spin, results in energy shifts which are much smaller than those of the fine structure. ”​

Now I admit that I don’t know what I am talking about in QM but I notice that magnetic moment and spin of the nucleus come up in the description of the hyperfine structure and that magnetic moment is tied to the angular momentum of the nucleus. This sounds to me like an inertial factor involved in the stability of atomic clocks.
 
  • #65
Torog said:
Now I admit that I don’t know what I am talking about in QM but I notice that magnetic moment and spin of the nucleus come up in the description of the hyperfine structure and that magnetic moment is tied to the angular momentum of the nucleus. This sounds to me like an inertial factor involved in the stability of atomic clocks.

It's not an inertial factor. The nucleus doesn't rotate in the way that a bar magnet rotates. The nucleus, like the spinning bar magnet, has angular momentum. The nucleus, like the bar magnet, has a magnetic moment. So in these respects the nucleus behaves "as if" it were a spinning bar magnet, and that is the reason it's called nuclear spin.

But if you try to account for these behaviors by modeling the nucleus as a sphere, or really an object of any shape, given its known mass and charge distribution, you just can't get it to work out. In other words, the nucleus cannot be modeled as a rotating object. It just doesn't work.

Inertia is not the well-formed concept in relativistic physics that it is in the Newtonian approximation. For example, you will find some physicists saying that the inertia of an object increases with its speed, and others saying it doesn't. It's not a debate about the physics, it's a debate about the meaning of a word.

I think the best you can do with drawing the kind of generality you're looking for is to say that all clocks involve a change in energy state. But I'm not sure even that will work.
 
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  • #66
Several posts claiming that time is non-physical have been removed. Please stick to accepted science
 
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  • #67
A clock is a device which measures time as a quantity.
Some clocks are a lot more accurate, atomic clocks are the best.
You won't need that accurracy to set your wake up alarm clock though
 
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  • #68
Aren't all clocks ultimately tied to the conservation of energy, because the conservation of energy is tied to the translation symmetry of time? So if you wanted to build perfect, eternal clocks, you'd need them to be in isolated systems and based somehow on conservation of energy, right?

And, since all events in the universe presumably must obey the law of conservation of energy, wouldn't that right there be the answer to the OP's question? I.e., the reason why two clocks built from different principles remain synchronized is that both are subject to the same laws about conservation of energy?

*I chose conservation of energy because as a noob physics student I am under the impression that ENERGY is tied to time while MOMENTUM is tied to space. But then again, time and space and energy and momentum are also intertwined, so let me just run away... ~~~ (>o_o)>
Of course in real life no clock is in an isolated system, so two clocks won't remain eternally synchronized. But in an isolated system where things like drag, etc are controlled, once synchronized they should remain that way forever regardless of how they are built, shouldn't they?
 
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  • #69
Sorcerer said:
Aren't all clocks ultimately tied to the conservation of energy, because the conservation of energy is tied to the translation symmetry of time?
This is an excellent and appropriate use of Noether’s theorem. It is very appealing.

All clocks are physical systems, so they have physical characteristics like energy, inertia, angular momentum, etc. So it is hard to say if a given property is the operating principle of all clocks.

So, for example, with the rotation of the Earth energy is conserved and angular momentum is conserved (linear momentum is not), but which is the one that we dub as being the operating principle of this specific clock? I would lean towards angular momentum over energy for that specific clock, but it isn’t clear since it has both and without both it would fail.
 
  • #70
Dale said:
This is an excellent and appropriate use of Noether’s theorem. It is very appealing.

I think it's circular. You first need to introduce the concept of time before you can state, address, prove, or otherwise have, that Noether's theorem. The theorem is a statement about time, it is not a definition of time or an operational definition of how to measure it.

All clocks are physical systems, so they have physical characteristics like energy, inertia, angular momentum, etc. So it is hard to say if a given property is the operating principle of all clocks.

You need to first have in hand an operational definition of time before you can define any of those quantities. Perhaps size is the one physical quantity that is the exception that all clocks possess.From Relativity and Common Sense: A New Approach to Einstein (1980), 65
A quantity like time, or any other physical measurement, does not exist in a completely abstract way. We find no sense in talking about something unless we specify how we measure it. It is the definition by the method of measuring a quantity that is the one sure way of avoiding talking nonsense about this kind of thing.

— Sir Hermann Bondi
 
  • #71
Mister T said:
I think it's circular. You first need to introduce the concept of time before you can state, address, prove, or otherwise have, that Noether's theorem. The theorem is a statement about time, it is not a definition of time or an operational definition of how to measure it.
The theorem is actually statement about symmetry, not just some predefined time. So doesn't requirement, that definition of time must respect the symmetry of physical world creates some restriction on the possible definition of time?
 
  • #72
Torog said:
How do we decide what is a clock and how do clocks that rely on different technologies stay synchronized?

a clock is any mechanism that is capable of measuring time ? for instance we could count the number of pulses from a pulsar . If we know the period of the pulsar then we can accurately measure time, without a feed back mechanism.

The period of the pulsar is prolly a function of its mass or some other, non time dependent, parameter that can be accurately measured.
 
  • #73
Ross Arden said:
a clock is any mechanism that is capable of measuring time ? for instance we could count the number of pulses from a pulsar . If we know the period of the pulsar then we can accurately measure time, without a feed back mechanism.

The period of the pulsar is prolly a function of its mass or some other, non time dependent, parameter that can be accurately measured.

I suppose all clocks only measure a subset of infinite time. What I mean by that is an egg timer only measures three minutes (say). But of course time goes more than three minutes. But unless it is possible to build a clock that goes for all time, all clocks only measure a subset of the entire time of the universe. In other words all clocks are egg timers, that just run longer than three minutes. I suppose going in the other direction you could have a clock that consisted of a single tick? which would be just a very short egg timer

the big bang is a clock that ticks every 15 billion yrs ?
 
  • #74
A clock, much like a meter stick for distance, measures time intervals, the time passed between events.
 
  • #75
Ross Arden said:
the big bang is a clock that ticks every 15 billion yrs ?

No; the Big Bang is not a periodic phenomenon. Unless you are expecting to see another one real soon now... :wink:
 
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  • #76
PeterDonis said:
No; the Big Bang is not a periodic phenomenon. Unless you are expecting to see another one real soon now... :wink:

assuming there was a big bang. That means there was enough mass in the universe , or some unknown phenomena, to cause the universe to collapse in on itself, to a singularity, and then expand again from that point. Unless there has been significant mass loss, or the phenomena no longer exists, then it is reasonable to assume at some time in the future there will be a second big bang ?

It may be a repeating phenomena with a say 200 billion year period

Another possibility is there are several universes and the material from one big bang is ejected towards another universe causing it to collapse so you have several neighboring universes in varying degrees of expansion and collapse.
 
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  • #77
Ross Arden said:
That means there was enough mass in the universe , or some unknown phenomena, to cause the universe to collapse in on itself, to a singularity, and then expand again from that point.

No, Big Bang definitely does not mean that... Big Bang theory states that universe was in a hot dense state a long long time ago, was expanding, etc.. No collapsing on itself, no singularity treated as a physical thing, no expanding from a point. Use "search" option, there has been many threads about BB clearing that kind of misconceptions.
 
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  • #78
Ross Arden said:
assuming there was a big bang. That means there was enough mass in the universe , or some unknown phenomena, to cause the universe to collapse in on itself, to a singularity, and then expand again from that point.

I think you have somehow misunderstood that line of reasoning. The latter is not a consequence of the former. That is, having a big bang does not imply that it was preceded by a big crunch. Cosmologists used to speculate that such a thing was possible and that a big crunch might be in our future; but ever since it was discovered, about 20 years ago, that the expansion is accelerating, they stopped. AFAIK.
 
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  • #79
Ross Arden said:
the big bang is a clock that ticks every 15 billion yrs ?
Clocks do not require periodic phenomena, just a measurable physical process with a predictable time rate. See: hourglass, radioactive decay...

...and in Jurassic Park, cases of beer.
 
  • #80
we seem to have drifted off the point ...can someone tell me where I went wrong with my analysis
 
  • #81
Ross Arden said:
we seem to have drifted off the point ...can someone tell me where I went wrong with my analysis
What analysis and what point?
 
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  • #82
Mister T said:
It's not an inertial factor. The nucleus doesn't rotate in the way that a bar magnet rotates.
OK as I said I’m not the expert.
But then you say:
Mister T said:
But if you try to account for these behaviors by modeling the nucleus as a sphere, or really an object of any shape, given its known mass and charge distribution, you just can't get it to work out. In other words, the nucleus cannot be modeled as a rotating object. It just doesn't work.
Here it sounds as if you are not sure how it works and I never suggested it might be a sphere.
You say:
Mister T said:
Inertia is not the well-formed concept in relativistic physics that it is in the Newtonian approximation.
Well it should be or if it is not then something is wrong – IMHO- tell somebody who has just had his car smashed by inertial forces “well sorry your car is all bent up but we have no way to understand the forces that caused all that destruction” Blame Newton not Einstien.

To get back to “it is not an inertial factor”
Lets see what I understand about Cs133. It has mass so the bits that make up the nucleus, the protons and neutrons have mass and even the electrons have a small amount of mass. The nucleus is emitting a radio wave at a frequency of 9,192,631,770 Hz.
( Getting my information in a cursory manner from : http://hyperphysics.phy-astr.gsu.edu/hbase/acloc.html)
According to the information source above the hyperfine emission comes from an interaction between a lone distant electron and the nucleus (& the dimensions are given for the nucleus and it doesn’t matter if it's round or shaped like a unicorn). It is a dynamic system. It moves – it’s some sort of an engine that produces these electromagnetic waves. You say the mass of the parts have no effect on the emission? It seems to me that if there is any movement involved in the hyperfine emission then the mass/weight of the parts must come into the equation.

Look at it from a GR (or SR?) perspective and with the principle of equivalence gravity and inertia can be interchanged so if the intensity gravitational field effects the clock - proven,of course – then why can’t we postulate that if the inertial mass of the clock changes then its rate will change?
 
  • #83
Torog said:
Lets see what I understand about Cs133. It has mass so the bits that make up the nucleus, the protons and neutrons have mass and even the electrons have a small amount of mass. The nucleus is emitting a radio wave at a frequency of 9,192,631,770 Hz.
( Getting my information in a cursory manner from : http://hyperphysics.phy-astr.gsu.edu/hbase/acloc.html)
According to the information source above the hyperfine emission comes from an interaction between a lone distant electron and the nucleus (& the dimensions are given for the nucleus and it doesn’t matter if it's round or shaped like a unicorn). It is a dynamic system. It moves – it’s some sort of an engine that produces these electromagnetic waves.
None of this is accurate. A nucleus is not an engine - it does not produce energy. In addition, "dynamic" and "it moves" are not synonyms.

A "state space" within which a dynamic system evolves need not involve three dimensional locations.
 
  • #84
The hyperfine interaction is between the magnetic moment of the nucleus, which is a constant, and the electrons in the atom. The transition frequency should be a know function of electron mass.
 
  • #85
jbriggs444 said:
None of this is accurate. A nucleus is not an engine - it does not produce energy. In addition, "dynamic" and "it moves" are not synonyms.

A "state space" within which a dynamic system evolves need not involve three dimensional locations.

I realize there it isn't possible to pin down shape of the nucleus or where any bits are at anyone time but is there movement or rotation in the nucleus?

I have heard that "spin" is actually spin with angular momentum and other that say it is "intrinsic" (whatever that means) and doesn't connote any movement.
 
  • #86
Torog said:
I have heard that "spin" is actually spin with angular momentum and other that say it is "intrinsic" (whatever that means) and doesn't connote any movement.
They're both right. The spin of a subatomic particle is indeed angular momentum, and it doesn't connote any movement or physical rotation. "Intrinsic" just means that nothing you do the particle will change its spin.
 
  • #87
Paul Colby said:
The hyperfine interaction is between the magnetic moment of the nucleus, which is a constant, and the electrons in the atom. The transition frequency should be a know function of electron mass.
Since the frequency of the radiation associated with that transition (as opposed to the "transition frequency") is a defined constant, whatever it is a function of, it is a constant function.
 
  • #88
Torog said:
Mister T said:
But if you try to account for these behaviors by modeling the nucleus as a sphere, or really an object of any shape, given its known mass and charge distribution, you just can't get it to work out. In other words, the nucleus cannot be modeled as a rotating object. It just doesn't work.

Here it sounds as if you are not sure how it works and I never suggested it might be a sphere.

Not sure how what "works"? Do you mean that the nucleus has a magnetic moment and an angular momentum? You measure those two quantities and don't get values of zero for either one. Is that what you mean by "how it works"?

And I agree that you never suggested it was a sphere.

Well it should be or if it is not then something is wrong – IMHO- tell somebody who has just had his car smashed by inertial forces “well sorry your car is all bent up but we have no way to understand the forces that caused all that destruction” Blame Newton not Einstien.

As I told you, it's not about the physics, it's about the meaning of a word. Inertia. Inertial forces are not the same thing as inertia, their values don't even have the same units.

When cars collide, by the way, they get smashed by electromagnetic forces.
 
  • #89
Torog said:
tell somebody who has just had his car smashed by inertial forces
Inertial forces never ever smash a car. They are strain free. They occur in non inertial frames, and can be made arbitrarily large by choosing appropriate coordinates. Cars don’t get smashed or not if you choose a different coordinate system.

Torog said:
It has mass so the bits that make up the nucleus, the protons and neutrons have mass and even the electrons have a small amount of mass.
All clocks have mass, so they all have inertia. So what do you mean by “inertial factor”? Do you merely mean that it has inertia? If so then it is a fairly trivial statement that doesn’t describe much about clocks. Do you mean something more?

Clocks have inertia. Cars have color. Color is not the operating principle of a car. Are you simply stating that clocks have inertia or are you trying to say that inertia is the operating principle for all clocks? Are you merely saying the equivalent of “all cars have a color factor”.
 
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  • #90
jbriggs444 said:
Since the frequency of the radiation associated with that transition (as opposed to the "transition frequency") is a defined constant, whatever it is a function of, it is a constant function.

Google yields...

"Transition frequency may refer to: A measure of the high-frequency operating characteristics of a transistor, usually symbolized as f. A characteristic of spectral lines. The frequency at which changes in the hyperfine structure of atoms occur. Turnover frequency in enzymology."

Seems to match my usage? Did I miss a memo?
 
  • #91
Paul Colby said:
Google yields...

"Transition frequency may refer to: A measure of the high-frequency operating characteristics of a transistor, usually symbolized as f. A characteristic of spectral lines. The frequency at which changes in the hyperfine structure of atoms occur. Turnover frequency in enzymology."

Seems to match my usage? Did I miss a memo?
The frequency of the radiation corresponding to the hyperfine transition in the ground state of the cesium atom is not the rate at which changes in the hyperfine structure of atoms occur.
 
  • #92
jbriggs444 said:
The frequency of the radiation corresponding to the hyperfine transition in the ground state of the cesium atom is not the rate at which changes in the hyperfine structure of atoms occur.

Hyper fine structure is a property observed in spectral lines of an atom. This has zip to do with the rate of transition. Not all transitions need be to the ground state. It's an RF spectral line.
 
  • #93
Paul Colby said:
Hyper fine structure is a property observed in spectral lines of an atom. This has zip to do with the rate of transition. Not all transitions need be to the ground state.
Fair enough. I mis-read your reference to "frequency at which" as "frequency with which".
 
  • #94
Paul Colby said:
The hyperfine interaction is between the magnetic moment of the nucleus, which is a constant, and the electrons in the atom. The transition frequency should be a know function of electron mass.

So if the mass of the electron changes (in my imaginary world) does the transition frequency change?
 
  • #95
Torog said:
So if the mass of the electron changes (in my imaginary world) does the transition frequency change?
That depends on how* the mass changes. Specifically, does the mass change in a way that also changes the fine structure constant (or other dimensionless constants) or does it change in a way that they do not change? The measurable transition frequency depends on the dimensionless constants like the fine structure constant.

*how meaning the details about the other changes that might be associated, not the mechanism of change
 
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  • #96
Torog said:
So if the mass of the electron changes (in my imaginary world) does the transition frequency change?

The interaction Hamiltonian which determines the frequencies of transition depends on the magnetic moments which depend on particle mass. Everything changes if ##\hbar## changes as well. These are all observed to be constant as far as I've heard.
 
  • #97
Torog said:
So if the mass of the electron changes (in my imaginary world) does the transition frequency change?
Why does this even matter? The mass of an electron is fixed.
 
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  • #98
Torog, I appreciate your thinking, and then questions following on how we might define a clock. This is a good thread to help at least some of us attempt to properly anchor the roots of time itself.

First, I should correct my previous assertion (below) that all clocks rely on angular momentum... not certifiably true. It arose from a different, also unmentionable personal idea.
Wes Tausend said:
All our clocks have this common denominator. They all rely on angular momentum, or a portion thereof , one way or another, to stay synchronized and count off rotations or portions thereof (pendulum).
DrGreg properly rejected my reasoning on a surviving earlier post and I hereby acknowledge he is correct; strictly angular momentum cannot be the charred key we seek here. My bad. :oops:

I find of particular interest what Sorcerer and Dale have discussed above in posts #68 & #69. While I struggle to understand the abstract math symbols of Noether's Theorem, I think I do recognized the conceptual value of, "the principle of least action", as partially worded in this first paragraph. This paragraph seems very much along the lines of Occam's Razor, or as Maupertuis supposedly felt, that "Nature is thrifty in all its actions".

It seems that the ultimate object of science is to simplify whatever processes and observances of Nature that we can. For instance, we might strongly suspect Mother Nature is lazy, that she accomplishes her vocation in the simplest manner possible... and when sufficiently 'cooked', these actions should boil down to fundamental principles... in other words the very charred essence of what we seek. I really like the simplicity of conservation of energy idea for this and other reasons.

Prior to the conservation of energy posts, I was tempted to come back and suggest that, since all classical clocks seem to at least rely on non-erratic motion events, that perhaps conserved general momentums (not just angular) were still the key. Even a candle flame, water or sand must move non-erratically to usefully differentiate the increments as a clock. But 'conservation of energy' seems a much better key now that it has emerged from the soot... because 'conservation of energy' allows not just conserving momentum, but storing that momentum for reuse as counter-momentum if we wish. Clocks commonly work by stored energy and each burst is measurably the same as last. As food for thought, it seems perhaps an escapement loop principle somehow regulates them all.

In a non-classical view, regarding quantum behavior of atoms when remarks on motion were given by Mister T, I am still not so sure I can draw an obvious conclusion that there is an obvious discernible atomic counterpart to classic laws of motion, but that is just me. In my quantum fog, it seems we should only know either the position of the 'tiny' hands or the rate, but not both at the same time. Yet atoms furnish us a great timepiece, apparently by rate alone. It is like a blind man that can hear, and use, the precise tick-tock but need not see the position of the hands to tell time.

But then conservation of energy was brought up. Ok, I know energy transcends both mechanical and quantum. This is better. Just "hearing" the tick-tock of an atom is the process of periodic electromagnetic energy escaping, enough as to form a useful timepiece, particle position notwithstanding. The electromagnetic energy will escape and tell us time until it runs out, or ceases to be applied, like any other clock. Perhaps someone could explain if both atomic and mechanical share a comparable hidden escapement mechanism to not release their energy nearly all at once. Seems maybe worth a Nobel Prize... unless it's been done.

Torog said:
You qualify the above with (pendulum). Isn't it possible that if you drill down into the mechanism of all clocks you will find Inertial mass somewhere in the regulating mechanism.

Thanks, this is what interests me, the how or physics of the regulating mechanisms of clocks.

It is still not so clear to me why 'drilling down' would not succeed, why Nature would suddenly abandon her simplicity right at the bottom of the hole. It's difficult to leave Einstein's side and not share his desperate want to discover why random motion seemingly rules so non-erratically at the core. How can something so random as the ghostly gears of an atom be our best clock? Perhaps we will only really know the atomic mechanism in a heuristic mechanical sense, if or when Einstein's dice ever reveal their secret. Quantum gravity heck; what is quantum time? Non sequor... :wideeyed:

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It seems a thread like this, where there is not a specific single answer to cite, elicits more opinions that border on speculation. The safer route seems to be saying not much, which I've tried to avoid. I hope I am ok today.

To be upfront, I was the (or a) guilty party in earlier setting foot outside the rules box and got a time-out. I apologize, my zeal to somehow add insight occasionally precedes my head. My uncited previous post, especially about cosmology, was removed and I deserved it. I do very much continue to appreciate the tedious behind-the-scenes work done here by Mentors even when it turns out I'm the rascal gone Beagle Boy. So thanks, Mentors.

And thankfully Torog's worthy clock thread was not locked on my account. :smile:

Wes
 
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  • #99
russ_watters said:
Why does this even matter? The mass of an electron is fixed.

This is just what I was trying to understand. The stability of the electronic clock is at least partially based on the fact that the mass is fixed.
I would like to say more but it is not a subject for this forum.
 
  • #100
@Torog you didn’t answer any of my requests for clarification on this topic.
 
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