On 09/23/2011 03:12 PM, Stephen A. Lawrence wrote:
In fact, the questions aren't nonsense; they just need to be carefully
posed to get sensible answers out of them in a universe where SR applies.
There is a "distinguished frame" for the universe: The rest frame of
the three degree background radiation. There just is one inertial frame
of reference in which that's isotropic -- in all other frames it's red
shifted in one direction, blue shifted in the other. That frame is
(presumably) the frame which is at rest relative to the primordial fireball.
Furthermore, if the universe is a compact manifold and "folds back on
itself" -- such as the surface of a sphere -- then there is an intrinsic
"rest frame" as well, which can be found by sending pulses of light
simultaneously in opposite directions. If the universe is closed, and
the light eventually comes back to the emitter, then there is just one
inertial frame in which the two pulses will arrive back at the emitter
simultaneously.
More obscurely, if the universe is closed, then the frame just mentioned
is the one in which the Sagnac effect is null. All other frames are (in
effect) /rotating/ (going 'round and 'round the universe).
Fair enough. You are proposing some hypothetical experiments to detect
absolute movement of a given frame.
But I was positing a slightly different question. Let me make myself
clear with an example. I'll adopt a kind of dialog to facilitate the
exposition. Please don't feel I'm addressing you directly.
Let's look at an image of the Milky Way, like this one:
http://upload.wikimedia.org/wikipedia/commons/8/89/236084main_MilkyWay-full-annotated.jpg
We can now ask: What has caused the spiral arrangement of the stars?
Classical astrophysics will say that gravity has caused it. And because
gravity only acts between material bodies, it will posit that, due that
there is not enough visible matter to account for the missing momentum
and velocity of some parts of the system, there must be some dark matter
which is causing the additional gravitational pull.
Now, looking at the picture again, I can ask you: what is moving in the
galaxy? In general, you'll answer that stars, dust clouds, etc. are
moving, and that their movement has taken a spiral form, again, due to
gravity and due to a given initial rotation of the system, which was in
the past a giant dust cloud of some kind(which was rotating who knows
why), and gradually developed stars and planets out of the initial
irregularities.
And then I'll ask you: the empty space between stars, planets, etc.
which is in the galaxy, is also moving? You'll probably answer that,
given our current understanding of the matter, only matter can move, not
empty space. Moreover, you'll cite scientific premises like Occam's
razor and the like, to announce that we shouldn't multiply the entities,
that only observables and measurable things must be considered, etc.
And then I'll answer that it strikes me as completely self evident that
what has caused the beautiful spiral arrangement of the stars in the
galaxy arms is the movement of space itself. It was and it is space
which is moving and rotating, and which is carrying along the stars,
dust clouds, etc. which are evolving and condensing in stars and star
systems, and forming beautiful galactic arms and whirlpools. Matter is
being carried along by the movement of space itself. There is no dark
matter at all, but rotational space flow.
Again, you'll cite Occam razor's and the like, to say that we should not
multiply entities, talk about unobservables, that science is about the
measurable and the ponderable, etc. And I'll probably tell you that the
movement of space is clearly observable by its effects, that you should
reflect on the spiral arms of the galaxy, etc. I'll probably tell you
too that for me science, real science, is about knowledge of the way
things really are. And then you'll probably start to cite the
nominalists (again) to question the nature of reality, to posit that
real is only that which can be directly observed, that the brain
attaches meaning to the world, and the like.
Is the slight difference clear enough now?
Best regards,
Mauro
On 11-09-23 01:53 PM, Mauro Lacy wrote:
Vorts,
So, when I first heard about zero point energy years back, I assumed
it was something I had already theorized myself when struggling with
the concepts of relativity (which still bugs me, for the reasons I'm
about to list) as I was mentally using the term Zero Point already.
Imagine my dissapointment...
Anyways, I'm a biologist and chemist more than a physicist, so PLEASE,
correct me where I am wrong. As the velocity of an object increases,
its apparent mass increases, and time slows, for that object, yes?
And the time dilation and mass increase is "relative" to the velocity
based upon the observer being a zero point. For 3 objects moving in a
straight line in the same direction, one at .1 c, one at .2 c, one at
.8 c, time dilation will be different for the .8 c object when vied by
the other two objects, yes? because its traveling at .7 c compared to
one, and .6 c compared to the other, correct?
If that is the case, is there a zero point? is there an intrinsic
velocity that pretty much EVERYTHING in the galaxy/universe shares?
If so, what happens to mass and the flow of time as you approach that
zero point?
The "velocity of the vacuum". Does the vacuum moves? At which speed? And
in relation to what? the immobile vacuum?
Einstein's SR disregards all those questions as nonsense, or better said,
"metaphysics". Speeds are only to be measured between material bodies, and
not correlated against any absolute reference, because that absolute
reference cannot be measured or determined.
Does something that cannot be measured or determined exists? In which
sense, or "where", it exists?
