[ExI] Dark Energy and Causal Cells

[Stuart LaForge]

John Clark wrote:

>> On Sun, Jan 21, 2018 at 7:30 PM, Stuart LaForge <avant at sollegro.com>
> wrote:
>> the fact that there is such a thing as CMB rest frame that our  galaxy
>> can be moving with respect to violates the Cosmological Principle  and
>> invalidates it.

> There is no violation, the Cosmological Principle says that on large
> enough scales the universe is uniform, and if you look at a cube about 200
> million light years on a side it is, and the laws of physics are the same
> in any reference frame. Movement can only be defined in reference to
> something else and the CMB rest frame is just the frame that is moving
> with the average velocity of all the matter in the universe.

But John by your own logic, all the matter in universe cannot possibly
have a non-zero average velocity unless there was something *else* out
there for the all the matter in our universe to be moving toward or away
from. Or did you mean scalar speed rather than vector velocity?

Assuming that you meant velocity rather than speed, Friedmann has no
answer for what that something might be. Freidmann says that galaxies are
like raisins in a loaf of raisin bread rising in the oven. The raisins
don't move through the dough, but as the dough expands, the raisins are
pushed apart by the expanding dough. The problem is that our "raisin" is
clearly moving through the dough.

The big CMB hot spot, the Shapely super-cluster, and Dark Flow are all in
the same octant of the sky in the direction of the constellation
Centaurus. What could be out there pulling the Laniakea super-cluster and
even the Great Attractor toward itself if not another causal cell?

https://www.universetoday.com/113150/what-is-the-great-attractor/

> If movement
> is allowed to exist in the universe then obviously not everything in it is
> going to be moving at the exact same velocity, so the fact that the Earth
> is moving at a velocity slightly different from the average is not at all
> surprising.

Of course not. What is surprising is that the observable universe has a
non-zero average velocity for the earth's velocity to differ from.

> It should also be remembered that in all the colorful pictures of the CMB
>  the contrast has been cranked way way up, in actuality the difference
> between the hot spots and the cold spots is only about one part in a
> hundred thousand.

I am not talking about the minor cold spots and hot spots, I am talking
about the big one. At its maximum, the difference is more like one part in
10,000 to 20,000.

>> Couple that with the fact that the cosmic microwave background is
>> spatially the largest dipole we have ever measured,

> I'm not sure what you mean by that but it would be astounding if we
> didn't see a dipole in the CMB because if there were none that would mean
> if you plotted the velocity of everything in the universe the Earth would
> be in the exact center of that movement plot, and I would consider that a
> pretty wild coincidence.

But that so-called coincidence is exactly what the Robertson-Walker
predicts. If your loaf of raisin bread expanding in the oven is large
enough and each raisin can only see a couple of inches in any direction,
then the average raisin would observe itself at rest in the middle of an
expanding loaf of raisin bread. That analogy is right out of the cosmology
textbook and it is *not* what we observe.

> They are just using induction and induction is even more important than
> deduction in science and in life. And besides, what is the alternative,
> there are a infinite number of ways things could be "out there" so how do
>  you even start to think about it? The obvious way is to assume things
> out there are pretty much like things in hear and then see where that
> leads.

That's fine for a starting point but when you start encountering
contradictions based upon that assumption, you need to revisit those
infinite alternate explanations and try to find a way constraining them.
Or better yet, try to get infinity to cancel itself out like
renormalization does in QFT.

> Induction is a very useful rule of thumb, but it doesn't always work.
> Induction just says that in our universe things usually continue. If
> things always continued then induction would always work and things
> wouldn't be very interesting, all the atoms in the universe  would be
> arranged in a unchanging perfect crystal lattice that is infinite in all
> directions. A world where things never continue and induction never worked
> would also be dull, it would be nothing but white noise. Our universe with
> all its complexity and richness is between these two extremes, here
> induction is a great rule of thumb because it USUALLY works.

No doubt induction is a useful tool. But when infinity is involved,
induction breaks down. Bertrand Russell did a great job explaining this
using the analogy of a train here:

"Mathematical induction affords, more than anything else, the essential
characteristic by which the finite is distinguished from the infinite. The
principle of mathematical induction might be stated popularly in some such
form as "what can be inferred from next to next can be inferred from first
to last." This is true when the number of intermediate steps between first
and last is finite, not otherwise. Anyone who has ever watched a goods
train beginning to move will have noticed how the impulse is communicated
with a jerk from each truck to the next, until as last even the hindmost
truck is in motion. When the train is very long, it is a very long time
before the last truck moves. If the train were infinitely long, there
would be an infinite succession of jerks, and the time would never come
when the whole train would be in motion." -B. Russell

>> You yourself quoted Einstein to me once: "Every thing should be made as
>>  simple as possible, but no simpler." The Robert-Walker metric is too
>> simple.
>
> Everybody knows the universe isn't perfectly homogeneous and  isotropic ,
>  but you can get some pretty good approximations by assuming that it is
> on the scale of a few hundred million light years, and doing so greatly
> simplifies the equations of General relativity although they're still
> horrendously complex.

Yes, I concur. The Cosmological Principle is a good approximation on the
scale of 10^8 to 10^10 light years. But it breaks down past the Hubble
radius just like Newtonian physics breaks down near the speed of light.
That's the scale at which causal cells become a more useful approximation.

>> if you are in a spaceship being uniformly accelerated, then  as you
>> draw closer to the speed of a light, a big flat event horizon will
>> appear behind you and start following you around.  And the closer you
>> get to the speed of light, the closer the event horizon  will get to
>> your ship. If this event horizon contacts your ship, then  Bell's
>> Spaceship paradox
>> ensues and your spaceship breaks apart.

> Bell's Spaceship Paradox is not really a paradox. If I tacked a delicate
> string inside the cockpit of my accelerating spaceship from the front wall
>  to the back wall the string would NOT break because the  atoms and
> electromagnetic fields inside the string would shrink by  Lorentz
> contraction  at  the same rate as the atoms in the cockpit 's side
> walls. However if I tied  a string from the front of my spaceship to the
> back of another  spaceship 10  feet ahead of mine and  we both accelerated
> at the same rate the string would break because the atoms in the string
> would shrink just as they did before but  now there is nothing else
> between the two spaceships to counterbalance that effect, there is only
> empty space .

Actually you, I, Lee Corbin, and a whole bunch other list members, who I
miss terribly, discussed the Bell Paradox at length back in August 2008 in
the thread entitled "QT and SR". At first I didn't believe it, but then
upon analysis, I derived an equation that gives you the speed at which a
string of any given material would break based upon its tensile strength.

http://lists.extropy.org/pipermail/extropy-chat/2008-August/045168.html

I concluded that as your speed approaches the speed of light, the tension
in the string approaches infinity. That means that you could substitute
tungsten-steel bulkheads for the string and there would still be a speed
at which they would break. What I didn't realize at the time, however, was
that there was an event horizon called the Rindler horizon involved that
coincides with the plane of infinite tension.

In your example, the only reason the string wouldn't break is because your
engine would break and prevent further acceleration before the Rindler
horizon reached your cockpit. Also, I too don't think it is a paradox,
which is why I entitled my post "the Bell Effect".

In any case, spacecraft which can accelerate to near light speeds would
need to take the Bell Effect into consideration in their design. Meaning
that fuel considerations aside, flat disc shaped spacecraft would be able
to reach speeds closer to c than the long cylindrical rocket-like shapes.

Lol. Maybe the Bell Effect is why the "flying saucer" shape is so popular
with space-faring ETs. *Removes tongue from cheek*

Stuart LaForge