[ExI] physics

[John Clark]

On Sun, Apr 24, 2016 PM, William Flynn Wallace <foozler83 at gmail.com> wrote:

​> ​
> I read John's post with interest if not comprehension.  I did like the one
> about a blank page that is not a picture until a line is drawn on it
>  Without going through the obvious ('what is a picture'?), does this follow?
>

​A picture is a thing and a thing needs a boundary, that's all a artist
does when he draws, make boundaries on a blank paper. Without boundaries
there is no picture, there is no thing.  Meaning needs contrast, like being
inside a closed line as opposed to being outside of it.

​>​
> Say there is a cube of space (in 'outer' space) that has not one single
> atom of matter (violating entropy I suppose).  Does this mean that it is
> not in some sense 'space'?
>

Nothing, that is to say zero, is far too precise a number for quantum
mechanics, it permits a violation of the law of conservation of energy and
mass but only for a very short time. Empty space is not empty, it is a sea
of virtual particles popping into and out of existence. This may seem like
a theologian talking about how many
​ angels
can dance on the head of a pin but it is not because it can be detected
experimentally.

Consider the Casimir Effect. Quantum Mechanics says that in empty space
particles such as photons of light can pop into existence from nothing, but
only for a very short time; in accordance with the Heisenberg Uncertainty
Principle the more energetic the new virtual photon is the shorter the time
it is allowed to exist. The Casimir Effect is due to a quantum mechanical
consequence of these electromagnetic virtual photons.

If you place two flat uncharged mirrors close together then there can NOT
be virtual photons of every wavelength in the vacuum between the mirrors as
there are outside, only a wavelength equal to the distance between mirrors
are allowed, or half that wavelength,  or a third or a fourth etc (it's the
same reason a organ pipe will not make any sound but only sounds that
resonate inside the pipe). But outside of the mirrors there is no such
restriction and the virtual photons can be of any wavelength. Thus there
are more virtual particles in the vacuum outside the mirrors pushing them
together than there are between the mirrors pushing them apart. So the
mirrors will attract each other. This force was predicted to exist in 1948
but it wasn't until 1997 that it was confirmed in the lab to actually exist
with exactly the force that Casimir said it would have. So there is no way
space can be total nothingness.

Virtual particles are also the reason Black Holes will eventually
evaporate. Just like everywhere else right at the edge of the event horizon
of the Black Hole pairs of virtual particles, electrons and anti-electrons
for example will pop into existence and sometimes one of the particles is
just inside the event horizon and its brother just outside, so one gets
dragged into the hole while the other breaks free and transforms from a
virtual particle into a real one that can be detected by instruments far
from the hole. But that detectable particle had real mass and mass must be
conserved over the long run, so for the accounting to be correct the Black
Hole must have lost mass.

​> ​
> Some say our universe is expanding.
>

​​The
 universe is
​not only​
expanding
​ it's accelerating. ​


> ​> ​
> Does this mean that some 'potential space' exists beyond any matter that
> will become 'space' when some matter gets there?
>

​It means that some things that are now withing your cause and effect
horizon (things that you can change or that can change you) will someday be
outside that horizon. We can only see stuff that's less than 13.8 billion
light years away because light hasn't had enough time for it to reach us
yet, the universe just isn't old enough.     ​



> ​> ​
> Kissing my wife and kissing the air are different and I don't give a
> barrel of used food who says elsewise.
>

​I can't argue ​with that!

 John K Clark
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