I already expressed the opinion that propagation faster than c was unlikely.
However, propagation at close to c seems more reasonable: my distinct
impression is that thinking of molecules 'bouncing against' other molecules
as opposed to interacting with them via their associated (EM, gravitic,
etc.) fields may be naive - and while the fields interact more strongly as
the molecules get closer together (causing their relative speed and
separation to affect the *amount* of heat transferred), they *begin* to
interact as soon as the molecules move at all (or, in the extreme, the
farthest molecule *begins* to be affected - minutely, certainly
indetectibly, but affected, at least via classical ED, though perhaps QED
may cloud the issue - as soon as the first molecule starts to move, plus a
c-imposed delay).
- bill
Brian Inglis <Brian.dot.Inglis at SystematicSw.ab.ca> wrote in message
news:5HASOHZAgVLBVaW0NUFxy4Jisy6L at 4ax.com...
> Think physics and reality. Temperature is just a measure of heat,
> which is a result of molecular motion. Applying energy to some
> substances causes the molecules to bounce around more: we
> perceive this as heat and measure it as temperature.
>> Heat propagates as molecules transmit energy to other molecules
> by bouncing against them, so heat conduction is limited by the
> speed at which these molecules can bounce, and transmit energy to
> adjacent molecules.
>> It's a lot slower and less efficient than shipping the energy
> around as E-M radiation, to affect the target molecules directly.
>>> Apply too much energy to any real substance and you don't get
> heat transfer, you get a change in the substance: a chemical
> reaction, an absorption of energy, not heat transfer.
>> Theoretically, you can calculate anything, but if you don't take
> into account the limitations of some conductive substance, it
> probably isn't heat transfer that you're calculating, just some
> ideal mathematical construct unrelated to reality.
>> On Sat, 23 Oct 1999 16:31:28 -0400, "Bill Todd"
> <billtodd at foo.mv.com> wrote:
>> >I'm not sure that's relevant: the *degree* to which the top-side of the
> >frying pan heats up is related to the heat capacity (if I recall the term
> >correctly - or perhaps it's specific heat?) of the frying pan - i.e., the
> >more heat it can absorb per unit volume for a given temperature rise, the
> >slower the temperature of a portion far from the heat source will rise.
But
> >that doesn't prohibit instantaneous propagation (which would mean that
the
> >far portion's temperature rise would *begin* immediately, regardless of
how
> >slow it was).
> >
> >- bill
> >
> >Steven Vogel <spamvogel at iconn.net> wrote in message
> >news:38112AAB.1E02 at iconn.net...> >> Naturally, you're correct. As an experiment to prove your point, you
> >> could turn the burner on your stove on high. After ten minutes, put a
> >> cast iron pan on the burner and put your hand on the top of pan right
> >> away for ten seconds. After ten minutes, have the poster that said
that
> >> heat travels faster than the speed of light put their hand on the top
of
> >> the pan for ten seconds.
> >>
> >> The person who doesn't scream has the better grasp of reality.
> >>
> >> Bill Todd wrote:
> >> >
> >> > If heat in a substance does in fact propagate via the interaction of
> >> > particles and EM fields, it's hard to see how it could do so at a
speed
> >> > faster than c.
> >> >
> >> > - bill
> >> >
> >> > Erik Max Francis <max at alcyone.com> wrote in message
> >> > news:3810DBC3.3463B0BB at alcyone.com...> >> > > Ronnie Sahlberg wrote:
> >> > >
> >> > > > Well actually I am, but the equation is faulty. It is only a good
> >> > > > approximative model
> >> > > > of the physic characteristics of heat, not an exact description
of.
> >> > >
> >> > > Well, no kidding.
> >> > >
> >> > > > Examine function describing heat distribution along the string.
> >> > > > Examine value of this function at t=epsilon (epsilon approaching
0)
> >> > > > especially "interesting" are the values of this function
infinitely
> >> > > > far
> >> > > > from
> >> > > > point p. It is small but non-zero.
> >> > >
> >> > > This is doing the equation, not doing the physics.
> >> > >
> >> > > --
> >> > > Erik Max Francis | icq 16063900 | whois mf303 | email
max at alcyone.com
> >> > > Alcyone Systems | irc maxxon (efnet) | web
> >http://www.alcyone.com/max/> >> > > San Jose, CA | languages en, eo | icbm 37 20 07 N 121 53 38 W
> >> > > USA | Fri 1999 Oct 22 (43%/950) | &tSftDotIotE
> >> > > __
> >> > > / \ Do not seek death. Death will find you.
> >> > > \__/ Dag Hammarskjold
> >
>> Thanks. Take care, Brian Inglis Calgary, Alberta, Canada
> --
>Brian_Inglis at CSi.com (Brian dot Inglis at SystematicSw dot ab dot ca)
> use address above to reply
