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Originally Posted by Michael Mooney
I would not be so tempted. Magnetic fields are obviously curved.
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Spacetime is obviously curved in the presence of mass.
Quote:
Originally Posted by Michael Mooney
The Earth's... a bar magnet's... solar flairs... the aurora borealis. We can see the curvature as expressed by iron filings on paper over a magnet... or in the display of ionized gases near the poles.
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We can likewise see curvature expressed by earth, mars, mercury, comets, light—and all other paths made through the solar system or galaxy.
Quote:
Originally Posted by Michael Mooney
the curved force field of magnetism does not establish "The Curvature of Space."
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Indeed—magnetic field lines are curved in flat spacetime.
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Originally Posted by Michael Mooney
It is a "fabricated medium"... only a model... unlike magnetic force fields and curved light paths.
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Magnetic field lines represent a vector field and should not be reified. In a similar way, the dimpled depictions of spacetime like a bowling ball on a rubber sheet that you see in textbooks represent a tensor field and should not be reified.
Quote:
Originally Posted by Michael Mooney
Pyrotex: "I love the analogy between "time" and "ley lines".
Modest:: "I like it too. I think it was originally brought up in post #137:"
Your magnet example completely misses my point... as usual. (as per my above comments.)
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My magnet example did not address your point. It was neither a response to it nor a response to you. I will, however, address it now.
Quote:
Originally Posted by Michael Mooney
A brief exercise in logic...
Assertion: "Time is what clocks measure." (Implication: If clocks measure "it" then "it" must be "real" (as an entity of some kind.)
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In special and general relativity space and time are what clocks and rods measure. That is the definition of time in those constructs and so too is it the definition I've given. It's also, incidentally, a definition I'm rather fond of. It is simply a definition, not an ontological element.
Your stated implication that "time is what a clock measures" somehow advocates the idea that time is an entity of some kind (presumably an ontological entity) is not an implication I've made. I've simply defined the terms I'm using.
Incidentally, there is
no significant difference between my definition of time and yours:
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Originally Posted by modest
Time is essentially duration (which we might think of as being measured with a clock or any regularly repeating phenomenon)
post #590 |
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Originally Posted by Michael Mooney
Time is the *concept/measure* of event duration, like... one rotation of earth... one earth orbit around sun... the great cycle of the precession of the equinox...
post #576 |
So you might just consider how fervently you are objecting to my given definition of time and all the implications you think I'm making with it when it is indistinguishable from the definition you've given.
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Originally Posted by Michael Mooney
Assertion: "Ley lines are what specially designed dowsing rods measure."
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This is a valid definition. If you created charts full of ley lines which were found by dousing then you could most properly define "ley lines" as "what the dowsing rod measured". This makes the least amount of assumptions about the nature of what the lines represent.
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Originally Posted by Michael Mooney
(Implication: If dowsing rods measure "it" then "it" must be real (as a real Earth Force of some kind.)
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This would not be a logical implication. It's a fine analogy you're making. If someone said "time must be a real physical entity because clocks reliably measure it" then you could rightfully use this analogy and this objection. I haven't seen anyone in this thread say that or make that implicaion, but we're now fully prepared if somebody does
Quote:
Originally Posted by Michael Mooney
Your curved magnetic field doesn't even approach the ontological debunking of 'time as established by clocks' presented above.
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I don't know what this means. If you're trying to debunk my definition (which I stole from Einstein) then you're debunking your own definition as well. I'm fully open to defining space and time differently, but only if it is a useful or usable definition. As far as the ontology of time...
I personally do not believe distance or duration are ontological entities. I must admit that I do not understand their fundamental nature, so I could certainly be wrong. But, to me the time between events seems like a function of whatever matter or energy is interacting with the events. The distance between the earth and moon is not an ontological element in and of itself. Anything moving from one object to the other (including light) would include the property of distance, but the distance need not exist of its own accord.
~modest
As an aside, Michael, you might want to look up "inertia" and "momentum". In your second to last post to me you used the phrase "change in inertia" as a proposed cause of time dilation where I'm sure you're confusing inertia and momentum. I also noticed you're still saying "event duration". An event has the same meaning in philosophy and physics—it has no duration. I'm sure you'll take this constructive criticism like I'm trying to debate you... but
