Re: Define a clock

From: AllYou! (idaman_at_conversent.net)
Date: 10/14/04 

Date: Thu, 14 Oct 2004 09:47:25 -0400

"jem" <xxx@xxx.xxx> wrote in message news:kHubd.26781$UA.26108@lakeread08...
> AllYou! wrote:
>
> > "jem" <xxx@xxx.xxx> wrote in message
news:LD9bd.25587$UA.23283@lakeread08...
> >
> >>AllYou! wrote:
> >>
> >>>"jem" <xxx@xxx.xxx> wrote in message
> >
> > news:nnQad.22908$UA.19964@lakeread08...
> >
> >>>>AllYou! wrote:
> >>>>
> >>>>
> >>>>
> >>>>>"jem" <xxx@xxx.xxx> wrote in message
> >>>
> >>>news:y6xad.22452$%x.19646@okepread04...
> >>>
> >>>
> >>>>>>AllYou! wrote:
> >>>>
> >>>>>>>"jem" <xxx@xxx.xxx> wrote in message
> >>>
> >>>news:atR9d.21144$UA.21034@lakeread08...
> >>>
> >>>
> >>>>>>>>AllYou! wrote:
> >>>>
> >>>>>Finally, the point wasn't that the *observability* relates to whether
> >>>>>or not a thing is an invention of man. Rather, whereas I'm making
the
> >>>
> >>>point
> >>>
> >>>
> >>>>>that time is not a fundamental property of nature, then the fact that
> >>>
> >>>time
> >>>
> >>>
> >>>>>was simply conjured up by man disqualifies if as such a fundamental
> >>>>>property. As further evidence that it is not real, I also point out
> >>>
> >>>that
> >>>
> >>>
> >>>>>it's not observable.
> >>>>
> >>>>When someone asks you for the time, you look at your watch and answer
> >>>>them, don't you? Doesn't that imply that "time" is observable?
> >>>
> >>>
> >>>No. It says that motion is observable and that we've ordered certain
> >>>motions in our lives by another, much more highly predictable motion
> >
> > that we
> >
> >>>all have in common. The motion of the Earth on its axis and its orbit
> >>>around the sun are highly predictable and so we long ago picked those
as
> >
> > the
> >
> >>>standard by which we would order all events. But what's an event? An
> >
> > event
> >
> >>>is a point where motion changes. It's imaginary in the same way that
> >
> > the
> >
> >>>point of intersection of two lines is imaginary. In fact, even the
> >
> > lines
> >
> >>>are imaginary. But the issue here is that we need to be able to order
> >
> > and
> >
> >>>communicate about velocity/distance properties of various things and we
> >
> > do
> >
> >>>so by using the distance/velocity of the Earth as a standard. So what
> >>>happens when someone asks you the *time*? They've asked you for the
> >>>relatively precise position of the Earth relative to the sun as it
> >
> > moves.
> >
> >>So basically "time" is just a substitute for "the relatively precise
> >>position of the Earth relative to the sun as it moves" (since it's
> >>easier to ask for).
> >
> >
> > Not really. First of all, most people don't give any thought to whether
or
> > not *time* is real. All they care about is how one event relates to the
> > present. Insofar as my assertion that time is not a real preperty of
> > nature, there's a difference between the terms *time* and what *time it
is*.
> > Just because they use the same word does not mean that they're in any
way
> > the same.
> >
> >
> >>Well then, if "the relatively precise position of the Earth relative to
> >>the sun as it moves" is something observable and real, and if "time" is
> >>just a shorthand way of saying all that, doesn't that imply that "time"
> >>is observable and real?
> >
> >
> > Not in the context in which you asked the question in the first place.
If
> > the word *time* were used in the same sense in which I gave my answer to
you
> > (i.e., simply as a substitute for a much less convenient to describe
> > reality), then the answer to your question would be yes. Unfortunately,
> > many people consider time to be a real property of nature and in that
sense,
> > the answer to your question is no.
> >
> >
> >
> >>>>Sure, there could be lots of motion internal to such a device, but
> >>>>suppose the blinking light is emitted by a single point-like particle
> >>>>that's relatively stationary to you the observer. In that case what
> >>>>would you be observing?
> >>>
> >>>
> >>>Relatively stationary?
> >>
> >>not moving relative to you
> >>
> >>
> >>>You'll have to be more specific as to what you're
> >>>hypothetical really entails. What is a single point particle? Does
> >
> > this
> >
> >>>particle have any size whatsoever? How does it blink? Does it emit
> >
> > light?
> >
> >>Does the observability of time depend on these details?
> >
> >
> > I don't know how to answer that question because it's my contention that
> > time is not observable. Therefore, the observability of time depends
upon
> > nothing.
> >
> >
> >> Can't you
> >>conceive of pulses of light emanating from a single location?
> >
> >
> > Not without something at some level happening which would cause that
light
> > to be emitted. What you call details may very well be what supports my
> > assertion. IOW, the blinking light is not magically emitted. Something
is
> > happening on some level, even if it's sub-sub-sub atomic, which entails
> > motion of some type. To ignore this *detail* which is the basis of my
> > assertion and then claim that it's not valid makes no sense.
> >
> >
> >>>Does the light have a wavelength? Does that wave travel any distance?
> >>
> >>The light is what makes you aware that something has occured at the
> >>light source. It needn't be light of course, any signal would do.
> >
> >
> > And any signal did not just magically appear. If it did, then time
might in
> > fact be real. But no event of any type is independent of motion except
for
> > those we imagine.
> >
> >
> >>>>>When the Big Bang occurred, among other fundamental properties of
> >
> > nature
> >
> >>>>>which came into being at that instant or in the milliseconds
afterward
> >>>
> >>>were
> >>>
> >>>
> >>>>>the weak and strong forces, gravity, mass, temperature, space, and
> >>>
> >>>velocity.
> >>>
> >>
> >>>>How about change in velocity, and change in change of velocity, and
...?
> >>>
> >>>
> >>>How about it? What's your question?
> >>>
> >>
> >>Well, shouldn't this infinite collection of motion descriptors be added
> >>to the list of fundamental properties of nature?
> >
> >
> > The changing value of a property is a property? We're getting into
> > unecessary semantics here but I'm willing to play if you want to explain
> > your point.
> >
> >
> >>>>And you should really use a different word to represent this
fundamental
> >>>>aspect of motion that you've labeled "velocity", since that term
already
> >>>>has a specific meaning as the rate of change of distance wrt (with
> >>>>respect to) time. Suppose we add an underscore to the start of the
word
> >>>>that refers to the fundamental version.
> >>>>
> >>>>So tell me, how do you propose to measure _velocity?
> >>>
> >>>
> >>>As we do with all other fundamental properties of nature. How do we
> >
> > measure
> >
> >>>distance? We take a quantity of distance, give it a name (unit), and
> >>>establish it as a standard by which all other distances will be
> >
> > compared.
> >
> >>>The same with velocity. Take a fixed quantity of it (as best we can)
> >
> > like
> >
> >>>the rotation of the Earth, assign a unit to it, and use it as the
> >
> > standard
> >
> >>>by which all other velocities will be compared.
> >>
> >>I suppose we could pick a location on Earth and take its _velocity
> >>(relative to what?) as our standard, but how do I go about comparing
> >>that _velocity to mine when I'm out jogging?
> >
> >
> > The parenthetical question.......*relative to what*.......is a
non-issue.
> > When you establish an inch as a unit of distance, the very definiton of
> > establishing a unit is to establish a standard for comaprison. It is
that
> > to which other distances will be compared. The same is true of a
velocity.
>
> I'm don't have the time this AM to respond to your entire post, but I'm
> curious how you plan to obtain this unit of "velocity" which is not
> determined relative to something else. Can you describe the procedures
> for defining it and using it to make measurements?

Keeping in mind that the whole point of establishing a unit is to use *it*
as the basis for comparison and not the other way around, I suppose the
general answer would be that we'd have to do so in the same way we capture a
basic unit of temperature. We don't put on degree F in a bottle and take it
out when we need it. With velocity, we can either use a latitude on Earth
as it rotates on it's axis or we can build a mechanism which moves something
on a continual basis at a constant velocity. In fact, we build such
mechanisms now. The confusion begins when we call them clocks and further
assert that they *keep time* when all they do is produce motion at a
constant velocity.

>
> > The whole reason why all of this misconception about *time* came to be
is
> > that there is no convienent way to carry around a fixed quatity of
velocity.
> > We can carry a unit of distance and a unit of mass, but doing so for
time is
> > difficult. What's more, comparisons of different velocities is even
more
> > difficult. But these difficulties only serve to further explain how our
> > dependence upon the concept of *time* came to be. It certainly does
nothing
> > to advance the case that it's real.
> >
> >
> >>>In their own crude way,
> >>>sailors have been doing this for centuries. Out on the open ocean,
> >
> > distance
> >
> >>>was almost impossible to measure and so of the three sides of the magic
> >>>triangle (velocity, *time*, distance) they needed to develop a
> >
> > fundamental
> >
> >>>unit of velocity and use the velocity/time function in order to
> >
> > calculate
> >
> >>>distance. So they invented the knot.
> >>>
> >>
> >>Such methods are generally going to have very limited utility. I think
> >>it would become clear rather quickly that a measurement system based on
> >>_velocity wouldn't be practical. Let's explore the idea further if you
> >>disagree.
> >
> >
> > In fact, I agree. But the relative convenience of dealing with an issue
> > should not obscure the realities of it. In fact, one has nothing to do
with
> > the other except to further illustrate how this confusion evolved?
> >
> >
> >
> >>>>If something changes state or direction, doesn't that change have a
> >>>>beginning (i.e. a demarcation between not changing and changing)?
> >>>
> >>>
> >>>Yes it does, but an instantaneous change in direction of any mass would
> >>>require an infinite amount of energy and so none of these changes will
> >
> > be
> >
> >>>instantaneous.
> >>
> >>Of course that implies that circular motion (for example), where
> >>direction continuously changes, is impossible.
> >
> >
> > And had you put my response in context with your question as to change
of
> > direction having a beginning, you'd see that circular motion was
excluded
> > from the scope of both the question and answer. If these are nothing
more
> > than trap questions, I'll pass.
> >
> >
> >
> >>>>For comparison, can you sketch a similar description of how "distance"
> >>>>is measured?
> >>>
> >>>
> >>>I did above.
> >>>
> >>
> >>Yes, you did. You said, "How do we measure distance? We take a quantity
> >>of distance, give it a name (unit), and establish it as a standard by
> >>which all other distances will be compared."
> >>
> >>In common language the word "distance" is used in two different ways
> >>that for purposes of this discussion we should distinguish between. It
> >>can refer either to the separation between 2 objects/locations, or to
> >>the measurement (i.e. quantification) of the separation between them.
> >>Can we agree to use "distance" only to mean the latter (i.e. the
> >>measurement)? Do you view "distance" in this sense as real and
> >
> > observable?
> >
> > Sure.
> >
> >
> >>Apart from the semantics issue, I agree with you on the process of
> >>comparison by which distance is determined.
> >>
> >>Suppose we want to determine the distnace between 2 objects. Well,
> >>since the separation between those objects can change, the distance
> >>between them can differ depending on the details of the measurement
> >>process (e.g. if I start counting the number of meter sticks that fit
> >>between them today and complete the process tomorrow I could get a
> >>different result than if I complete the process today - see where this
> >>is going?).
> >
> >
> > But I fail to see the point of it all as it relates to the specific
question
> > at hand. Such is the problem with parsing posts down to their most
> > fundamental elements. The point here is that with length (distance, or
> > whatever other semantic you wish to apply to the concept we're
discussing),
> > we take a quantity of it and use that to compare to all others in order
to
> > understand and communicate. We can do the same with velocity, albeit
with
> > greater difficulty, but this cannot be done with *time* because there is
no
> > unit of time to be used in this way. All we know of time is a velocity
> > through a distance.
> >
> > Other than that, I fail to see the point of the treatise on the
semantics of
> > the term *distance* as it applies to this dialog.
> >
> >
> >>Do we need to bring "time" into this distance determination?
> >
> >
> > As you've constructed the hypothetical, it has nothing to do with
measuring
> > a fixed distance in a given FOR. However, to the extent that you wish
to
> > pursue this issue for other, unrelated purposes, you could complete this
> > process just fine if you had a given, fixed standard by which to compare
the
> > motion you've described and made your adjustments accordingly. In
effect,
> > that's exactly what you're doing anyway when you say you use *time*.
> >
> >

Relevant Pages

  • Re: Define a clock
    ... It says that motion is observable and that we've ordered certain ... More specifically, you'd be observing ... >> results of velocity through a distance. ...
    (sci.physics.relativity)
  • Re: Define a clock
    ... It says that motion is observable and that we've ordered certain ... the observability of time depends upon ... > I suppose we could pick a location on Earth and take its _velocity ... We can carry a unit of distance and a unit of mass, but doing so for time is ...
    (sci.physics.relativity)
  • Re: Define a clock
    ... complicated to think of it as just more motion and so he chose a constant ... motion, the Earth's rotation, and called it a clock. ... With distance, we can use a distance as a standard to measure it. ... >> The same with volume, velocity, charge, temperature, mass, and others. ...
    (sci.physics.relativity)
  • A definition of time.
    ... it produces a motion for one thing. ... position and the interval between those two positions is a distance. ... we observe distances all the time and we tend to quantify them. ... IOW, we observed a velocity. ...
    (sci.physics.relativity)
  • Re: Define a clock
    ... You'd certainly not be observing ... It's moving at some velocity thorough some distance ... enough motion will occur to trigger the change from one ...
    (sci.physics.relativity)