Re: Further on the proper use of the notion of *time* in science

shevek4_at_yahoo.com
Date: 12/07/04 

Date: 6 Dec 2004 19:07:12 -0800

jahn wrote:
> <shevek4@yahoo.com> wrote in message
news:1102383909.601713.297080@z14g2000cwz.googlegroups.com...
> >
> > AllYou! wrote:
> > > <shevek4@yahoo.com> wrote in message
> > > news:1102355857.124056.84020@c13g2000cwb.googlegroups.com...
> > > > Wow, the new google groups really sucks.
> > > >
> > > > Let me add for you: irrelevance noted.
> > > >
> > > > And my reply to that : irrelevance noted.
> > > >
> > > > Back to the physics (sorry for the diversion)
> > > >
> > > > You say: " mass is observable ".
> > > >
> > > > How so? I certainly feel a mass hitting my head, but then
again, I
> > > > also can watch the sun move across the sky.. so isn't time
> > observable
> > > > as well?
> > >
> > > Please make the case for me that observing a motion is observing
> > *time*. You're so
> > > emotionally and psychologically tied to the notion that the
motion of
> > the Sun *is* time
> > > that you look right over the fact that it's simply motion.
> > >
> > > So please make the case for me. I'd love to hear it.
> >
> >
> > As soon as you make the case that the neural stimulus from the
falling
> > brick is an observation of mass, I'll come back at you with the
case
> > that the neural stimulus from motion of the sun is an observation
of
> > time. Both arguments are equally valid.
> > I'd hate to be the innocent bystander that asks you for the time!
:)
> >
>
> Both arguments aren't equally valid.
>
> If two masses are held in contact by their mutual
> gravity it is only necessary to apply a separating
> force and feel a resistance to confirm that they are
> masses. It doesn't matter if you move them, how
> far you move them or how long it takes you to
> move them. The resistance to motion is sufficient
> proof.
>

Hi Sue.
OK, I see your point. It does matter however that you do move the
masses, and register a resistance. How do you know they have moved?
How do you know they have resisted? To know those things you must have
the concept of time..

And of course AllYou's argurment is still valid (though somewhat
trivial and annoying): all you've measured is a resistance to a force..
not a "mass".

> Taking the inverse experiment. If two masses
> are released some unknown distance apart
> and you only know the masses and a = 1/2 mv^2
> then you can't derive a unit of time without assuming
> a unit of distance. You can't derive a unit of distance
> without assuming a unit of time.

Mass is still defined with a sample material these days, usually water
is used.

However, the material must occupy a certain volume, so a distance unit
is required for the definition.. and as you pointed out distance
requires time to define it.

Distance could be defined with a sample, e.g. the distance between
carbon atoms in a diamond at STP.. and then the second could be defined
from that via light speed, e.g. the second is the amount of time it
takes light to travel from one carbon atom to another times x.

I think AddAll would like that better.. but basically it's the same.

>
> ...Well, I haven't been able to anyway.
> It is an interesting challenge and even if you don't
> find a solution (perhaps there is none) you will
> learn a lot things you never meant to in trying.
>
> Personally I would look to the electron for some
> gold standard of time or distance, but I have a gut
> feeling that HUP has things tricked up so you can't
> learn what you need to. Faraday's law is another
> possibility but I've had no luck.
>

Well I'm not sure who HUP is but you have hit the nail on the head with
the electron. An electron's behaviour near a cesium nucleus is usually
used.

Relevant Pages

  • Re: Further on the proper use of the notion of *time* in science
    ... >> If two masses are held in contact by their mutual ... The resistance to motion is sufficient ... >> are released some unknown distance apart ...
    (sci.physics.relativity)
  • Re: Revised Hypothesis
    ... > distance, assign a label ... > fundamental property which deserves the same priority in physics as do distance, mass, ... the ratio of distance to motion (two fundamental ... it is more accurate to state that we observe motion. ...
    (sci.physics.relativity)
  • Re: Revised Hypothesis
    ... > distance, assign a label ... > fundamental property which deserves the same priority in physics as do distance, mass, ... the ratio of distance to motion (two fundamental ... it is more accurate to state that we observe motion. ...
    (sci.physics.relativity)
  • Re: what is the relation between force and energy?
    ... > distances between electrons and nucleons, which increases energy). ... Having no temperature, VPs have no motion of their own, ... >> involve time, although in my opinion it does, because gravitation ... energy with more distance from a gravitational source, ...
    (sci.physics)
  • Re: Jeckyl wrote
    ... The change is from the viewpoint of the non-local observer. ... closure by the exterior observer would be a distance of 80 yards ... motion, ... Relativity does not demand length contraction. ...
    (sci.physics.relativity)