[ExI] Who's stealing our universe?

[Lee Corbin]

BillK points to the interesting

> Another article interviewed the scientists involved in
> this discovery and apparently they were quite surprised
> by theses unexpected findings.
> <http://www.space.com/scienceastronomy/080923-dark-flows.html>

The "science writer" responsible for this outrage should
be prosecuted. Thanks for bringing this thought-criminal
to the attention of the committee, Bill.

Some excerpts:

    When scientists talk about the observable universe, they don't
    just mean as far out as the eye, or even the most powerful
    telescope, can see. In fact there's a fundamental limit to how
    much of the universe we could ever observe, no matter how
    advanced our visual instruments. The universe is thought to have
    formed about 13.7 billion years ago.

Yes, I'm sure he read that somewhere, or someone mentioned it to him.
Okay. But then
                                       So even if light started
    traveling toward us immediately after the Big Bang, the farthest
    it could ever get is 13.7 billion light-years in distance. There
    may be parts of the universe that are farther away (we can't know
    how big the whole universe is), but we can't see farther than
    light could travel over the entire age of the universe.

The writer has no understanding whatsoever how the expansion of
the universe plays into this. At 300,000 AB [1], photons got free
when the universe became transparent to light, and some of them
started heading right at us, but got yanked further away from us
by inflation.  The poor photons knew where they were headed,
but to them the space between them and their target really blew up.

The best explanation is to be found in the book written
by the originator of inflation, Mr. Alan H. Guth [1]
himself, "The Inflationary Universe". On pages 182 - 184
he describes what went on.

That number, 300,000, is very important in what
follows.

    "At 300,000 years, the horizon distance was about
    900,000 light years. [Here Guth means that two
    photons starting out "nearby", i.e. within a tiny
    fraction of an inch at the Big Bang and aimed
    right at us but coming from opposite directions,
    would already have each been yanked back 900,000
    ly because of the stupendous inflation expansion.]

    "If the universe were static, the horizon distance
    would have been about 300,000 light years [since
    in *that* case we would have had only time to get
    ones aimed at us from that distance, since that
    was the age of the universe]. In an expanding
    universe, however, photons can make extra progress
    during the early period, when the universe was
    small, so the horizon distance is larger than one
    would expect."
    
Note that what Guth is saying is very tricky. Read the
above at least as much as to understand what scientists
mean by the terms, and how they use them, as to try
to understand what is being said. Guth goes on:

    "If we consider two photons arriving *today* [italics
    added] from opposite directions in the sky, then we
    can use the mathematics of the Big Bang theory to 
    trace back the trajectories to 300,000 AB. The 
    calculation, which takes into account the expansion
    of the universe, shows that the photons were emitted
    from two points [at the time] about 90,000,000 ly
    apart. Let A and B label the two points at which
    these two photons were emitted [one to the left of
    us 45,000,000 ly and the other to the right of us
    45,000,000 ly]. The uniformity of the cosmic background
    radiation temperature implies that the temperature
    was the same at points A and B (to an accuracy of
    one part in 100,000), yet they were separated from
    each other by  about 100 times the horizon difference
    [at the time]."
    
So he's saying, in effect, "now how the hell could that be? There
is no goddam way that they could be at the same temperature
unless something weird is going on---because ninety *million*
light years at only 300,000 AB makes that look impossible.
How could their temperatures have been reconciled? How 
could they have "known" each other thermodynamically?"

    "Since nothing travels faster than light, in the
    context of the standard big bang theory [get ready
    for his inflation!] there is no physical process
    that can bring these two points to the same 
    temperature by 300,000 years after the big bang."
    
So, he says in a footnote here, "The rate of separation,
therefore, was much larger than the speed of light", and
explains why your mind should not be blown by this.

In a caption to the diagram, he then goes on like
this (thank God for a little redundancy!).

     "The Horizon Problem of the Standard Big Bang Theory".
     [paraphrased by me, since you cannot see the diagram]
     The diagram shows a picture of the universe at 300,000
     years after the big bang, when the cosmic background 
     radiation was released. At the center of the diagram is
     the matter that will eventually become the Earth. At the
     left is point A, where one is headed towards us from the
     left. At point B on the right is where the leftward moving
     photon is coming at us from the right. They are only at
     90,000,000 light years away from each other!

     "The "horizon distance", however, was only 900,000 ly.
     The points A and B were separated from each other by
     about 100 times the distance that light could have traveled
     since the Big Bang."

So that science writer is clueless about how the terms are
used, and how inflation actually provided for a far, far
vaster universe than the little thing that we can see. Our
"horizon distance" of course, has never caught up to
what was propelled away so long ago.

Now, of course, it *could* be that we are exactly at
the center of all there is, and that indeed our "bubble"
only goes out as far as we can see. What is the $&%$!
chance of that? Can you just picture some aliens 10
billion light years from here saying, "Oh, gee, there must
be something special about that point off yonder at the
center, since we are so close to the edge of the bubble."

The writer and one scientist go on:

    They discovered that the clusters were moving nearly 2 million
    mph (3.2 million kph) toward a region in the sky between the
    constellations of Centaurus and Vela. This motion is different
    from the outward expansion of the universe (which is accelerated
    by the force called dark energy).

    "We found a very significant velocity, and furthermore, this
    velocity does not decrease with distance, as far as we can
    measure," Kashlinsky told SPACE.com. "The matter in the
    observable universe just cannot produce the flow we measure."

Well, duh! Do these guys think that the observable universe is
all that there is? Or that maybe just beyond the edge of what
we see, it all becomes Very Different? What a coincidence
that we are at the exact center of normalcy. Yes, I understand
that they have evidence of something outside our visible 
universe, but it is *not* outside our bubble, which is probably
infinite.

The inexperienced science writer now tries his own hand at
explaining:

    A theory called inflation posits that the universe we see is just
    a small bubble of space-time that got rapidly expanded after the
    Big Bang. There could be other parts of the cosmos beyond this
    bubble that we cannot see.

No, the universe that we can see is not any "bubble" as the term
is commonly used. Again, if it were, wouldn't that be a fantastic
coincidence that we're right at the center of it. Perhaps the ancient
anthropomorphism and mankind needing to be at the center of the
universe is sneaking back into his thinking.

    In these regions, space-time might be very different, and likely
    doesn't contain stars and galaxies (which only formed because of
    the particular density pattern of mass in our bubble). It could
    include giant, massive structures much larger than anything in our
    own observable universe. These structures are what researchers
    suspect are tugging on the galaxy clusters, causing the dark flow.

I *hope* that the science writer has just consulted his own imagination
here. OF COURSE the universe just contains stars and galaxies right
outside our visible universe. It may be that some of it is grouped
weirdly, and that's what they've found. But the *uniformity* of our
universe begins at only about 300,000,000 light years, much, much
smaller than the visible universe. Tegmark said *specifically* that
all the small scale variations wash out when you get up to about
300,000,000 light years, and then it's uniform after that (or at least
that was what was thought until now). But that does not change
the fact that the very little patch we live in, some 300,000,000
light years in diameter, is more or less regularly repeated right up
to the edge of the visible universe, i.e., picture the visible universe
(at which we are indeed at the center of) as being tiled by very,
very similar patches all the way out to 42 billion light years away,
i.e., more than 42x3 = 120 similar patches in each of the three
directions. 

And because of inflation, the radius of the observable universe
turns out to be, when they did all the calculations, about three
times the 13.4 billion years that light has been in straight line
motion (i.e., 300,000 AB), or 42 billion light years. Hence
our visible universe has a diameter of 84 billion light years.

Yet in one direction, well, they've seen something odd. Could be,
I suppose.

The science writer then actually quotes this person Kashlinsky
(I dare not say guy, because "Alexander" could be a woman's
name these days.)

    "The structures responsible for this motion have been pushed so
    far away by inflation, I would guesstimate they may be hundreds of
    billions of light years away, that we cannot see even with the
    deepest telescopes because the light emitted there could not have
    reached us in the age of the universe," Kashlinsky said in a
    telephone interview. "Most likely to create such a coherent flow
    they would have to be some very strange structures, maybe some
    warped space time. But this is just pure speculation."

Dr. K. is giving one a bad idea of how inflation works, and is
contributing to the incredibly antiquated notion that we are
at the center. Nothing was pushed away!  Or, if you must speak
that way, we were just as pushed away as was it. Instead, 
the *space* between galaxies was expanded, nothing got
pushed. And then he ends with "But this is just pure speculation".
Science writing, I fear at it's worst.

I just hope that they don't have an affirmative action program for
Poles or Russians or whatever the hell he or she is, and that we
can depend on his or her words---so long as we understand that
he or she is still in the process here of explaining what the speed
of light is to that inexperienced science writer.

Lee


[1] "At 300,000 years AB", (i.e. After Bruno, the
name of our universe, which, so far as I know, I was
the first person to have named, as I was notified in
a couple of emails from people I had never heard
of back a few years ago, or, if you wish, After Bang,
or After Beginning)

[2] Alan Guth explains in his book that the acronym
GUT for "Grand Unified Theories" is not faithful to
the  Greek roots of the word "theory", where "th" is
represented by the single letter phi, i.e., that the proper
acronym is really GUTH.