Anh has a point. Nature doesn’t create
vending machine under a f lickering f luores-
shapes like that, not when it’s only got bom-
cent light, and I tell it to brew me some dark
bardment to work with. There’s a peppery
pu-erh. While it works, I have time to think.
patina of miniature craters all around, some
I have time to know I can’t convince myself
too small to f it my little f inger in if I could
of the lie. I have time to realize that nothing I
stand there unprotected on that Mimantean
do matters. All of Herschel’s telemetry will be
shore. It looks like a statue of something that
parceled out to the world soon enough; we
slithered, maybe, or drummed along on
didn’t spend hundreds of millions getting it
enough legs to make slackers of millipedes,
out to Saturn just for the thrill of it. Some con-
something that never lived on Earth. It looks
spiracy nut will f ind the watcher, the same
grey but real, like some kind of watcher who
way they found glass towers on the moon or
can’t bear to let Saturn out of its sight.
Martian pyramids, except this one will be
“It’s . . .” I try to come up with an excuse,
right. It’s easy to deny the truth of something
any excuse, out of fear. If Herschel and Anh
that doesn’t exist, but when it’s right there on
were right, today was the day people had been
the other side of a camera, the truth has many
looking forward to for hundreds of years. Real
paths to victory.
evidence of an extraterrestrial civilization close
We would know better then, all of us. We’d
enough to touch, an answer to the Fermi Para-
know that there had been beings greater than
dox that Caesar might have given: we came,
us, grander than us, who’d come here and left
we saw, we left. The news would roll like a
their mark and disappeared. The next ques-
tsunami across the world, washing away hu-
tions are easy to guess: What happened to
manity’s conviction that they were alone . . .
them? Where did they go? Will the same thing
and then what?
happen to us?
I want to look at the sky and feel wonder,
Herschel can’t tell us that. Neither can Mi-
that exhilarating connection to the world be-
mas. It’s a thing so lifeless, the Universe will
yond the sky no matter how much it dwarfs
end before it can die. All it offers is a grey im-
me. To feel the grandeur of stars that’ll shine
mortality. If no one retrieves it, Herschel will
for a hundred billion years, nebulas that paint
stay there until the sun retreats into a pale,
the darkness in reds and violets and every col-
cold diamond, just as the watcher. It’s the per-
or in between, galaxies that f low like silver
fect place for a gravestone.
rivers across the night. When I look at the arti-
The vending machine gives a teakettle’s
fact, that watcher, all I see is emptiness. I see
whistle. I take my drink and, after a moment
ancient stars cast f lickering light over decay-
of thought, dip a f inger in it. I expect it to
ing cities, nebulas that veil the faces of shat-
burn and sear, but it’s been a while since the
tered worlds, galaxies where civilizations
machine has pulled down an update. The pu-
drowned with no one to hear their cries for
erh is tepid and tastes like ash, or Mimantean
help.
dust, and it shreds my insides on its way
There’s still plenty of time for humanity to
down.
carve its own tombstone.
I don’t expect anything to taste much bet-
“It’s a glitch,” I say. “Can’t be real. No way.”
ter, now that I know what I know. Still, I carry
Over Anh’s protests, I tell Herschel to keep
it with me back into Mission Control. Even
on moving—there might be a good hole just
when all the paint has f lecked off the world
ONE TO WATCH
103
ANALOG
and the gears are grinding, we must carry on.
howling and lonesome. Before we went out
Anh dashes away from my station as soon as I
among the stars, they were filled with civiliza-
reenter and stamps straight to me.
tions that had faced their own troubles and
“You’re not going to hide this,” Anh says.
made it through.
“I’d like to,” I say. “I can’t.”
We know better now. Because of Mimas. Be-
cause of me. ■
If I could do it over again, I’d make sure no
one ever knew. Every explorer tries to forget
Andrew Barton hid a pun somewhere in
the possibilities they’re crushing with every
this story; see if you can find it! Andrew has
step. Take Mars; it used to be a world of ele-
had stories in Analog, On Spec, and an-
gant canals and romantic adventure—then we
thologies from Bundoran Press and Allitera-
learned what it was, and no matter how hard
tion Ink, tweets at @ActsofAndrewB, and
we closed our eyes and wished it was other-
occasionally reviews Golden Age science fic-
wise, it would only ever be a rusted desert,
tion at actsofminortreason.com.
IN TIMES TO COME
Our lead story for March/April is from Alec Nevala-Lee: a strange vision in the remote Alaskan wilderness leads a pair of intrepid reporters to investigate, but will it ultimately be more—or less—than it seems? Find out in “The Spires.”
Then we pick up with Belisarius and his motley crew of criminals and mercenaries in the second installment of The Quantum Magician, from Derek Künsken. Bel has assembled the team he’ll need to pull off his plan, but is even the most advanced mind in the Known Systems capable of foreseeing every pitfall?
Then an experiment hides a shocking secret in “Lab B15” by Nick Wolven; a green World War II serviceman in a Boeing Superfortress gets more than he enlisted for in “The Tailgunner’s Lament,” from Brendan DuBois; an invasive ecosystem turns out to be more invasive than normal in Bruce McAllister’s “Frog Happy”; one chance to avert disaster rests with the last person anyone expects, in Brian Trent’s “An Incident on Ishtar”; Gregory Benford brings us a look at the science journals of 2116, in
“Physics Tomorrow”; people will always find new ways to make a living, as we see in “The Streaming Man,” from Suzanne Palmer; an alien makes an all-too-human mistake with tragic consequences in “The Selves We Leave Behind” by Gwendolyn Clare; automated cars get a little too self-directed Mary Turzillo’s “Car Talk”; and desperate times call for desperate measures, in Susan Forest’s “Sun Splashed Fields and Far Blue Mountains.”
Plus we’ll have articles and stories from C. Stuart Hardwick, Tom Ligon, James Van Pelt, Tom Jolly, Rich Larson, and Jerry Oltion, as well as a Probability Zero from Bill Pronzini, and all our regular fact articles and columns.
See you then!
104
ANDREW BARTON
THE ALTERNATE VIEW John G. Cramer
DO BLACK H
OLES REALLY EXIST?
requently, one sees science press head-
photosphere. In other words, the photosphere
lines describing observations of black
has a radius of 3/2 times r . In the surface of
g
holes: the discovery of a black hole at the
the photosphere, light is bent into a circular
Fgalactic center or the discovery of a pair orbit by gravity and can orbit the compact ob-of orbiting super massive black holes in merg-
ject.
ing galaxies or the aLIGO detection of gravita-
The presence of an event horizon is the es-
tional waves created in the spin-down merger
sential defining characteristic of a black hole.
of a pair of binary black holes. These days,
It is the surface within which gravity is so
there are so many astrophysical observations
large that the time-slowing effect of the gravi-
on Earth and in space that are attributed to
tational red shift causes time to stop altogeth-
black holes that questioning their existence
er. To an external observer, any infalling ob-
seems rather absurd.
ject would appear to stop and freeze on the
However, it is important to point out that a
event horizon and would never go any farther
black hole’s event horizon, the region where
in. On the other hand, according to GR an un-
time comes to a complete halt, has never
fortunate observer who was falling into the
been observed. Further, Hawking radiation,
black hole would notice no particular effect
the predicted emission of thermal photons
when crossing the event horizon.
arising from quantum effects at the event hori-
The interior of a black hole inside the event
zon, has never been detected. The fact is that
horizon is causally disconnected from the out-
the term “black hole” is commonly used to in-
side, and nothing that enters the event hori-
dicate any collapsed stellar object that is more
zon can escape (except for advanced waves;
massive than a neutron star. Most of the “black
see my book The Quantum Handshake, Sec.
hole” observations that we hear about come
6.21). Like Las Vegas, whatever happens in-
from emissions from the accretion discs of
side the event horizon stays inside the event
such massive compact objects, which may or
horizon. Furthermore, GR predicts the even-
may not actually be black holes.
tual formation of a pathological singularity
What is the difference between black holes
within the event horizon. The singularity is
and other massive compact objects? Black
completely isolated from the outside world,
holes are a major prediction of Einstein’s gen-
shielded from it by the event horizon. Howev-
eral theory of relativity (GR), currently our
er, within the singularity’s domain of influ-
standard model for gravity. GR predicts that
ence, the familiar laws of physics must break
when a massive fuel-exhausted star can no
down, with unknown consequences.
longer be prevented from final collapse by the
repulsion of nuclear forces, its core falls in-
There are a number of reasons why many
ward in a supernova explosion and a black
physicists distrust the above GR description of
hole forms, complete with an event horizon at
black hole formation and behavior. The singu-
the Schwarzschild radius r
given by
larity, whether hidden or not, is considered by
g
r =2GM/c2, where G is Newton’s gravitational
some to be an unphysical deal-breaker as a pre-
g
constant, c is the speed of light, and M is the
diction of a physics theory. Further, the GR de-
mass of the star. Half a radius outside the event
scription ignores the effects of quantum me-
horizon, black holes have a region called the
chanics. There is an intrinsic incompatibility
105
ANALOG
between our present standard theories of gen-
black hole. However, they are predicted to
eral relativity and quantum mechanics, and we
show distinguishable differences when gravi-
do not have a theory that correctly includes
tational waves are generated by a merger.
the effects of both. It is speculated that if we
The aLIGO Detector, with sites in Hanford,
did have a more comprehensive theory of
Washington and Livingston, Louisiana, has
quantum gravity, it would significantly alter
now detected gravitational waves three times:
the scenario of black hole formation, particu-
on September 14, 2015, December 26, 2015,
larly in the regions of the event horizon and
and January 4, 2017, with a fourth lower con-
the singularity.
fidence event also detected on October 12,
One critic of GR is George Chapline of the
2015. The analysis of these events indicates
Lawrence Livermore National Laboratory (see
that all were produced by mergers of pairs of
AV 129 in the September 2005 issue of Ana-
massive compact objects with masses ranging
log). Chapline has argued that, if properly ap-
between 6 and 37 times the mass of our Sun.
plied, quantum mechanics will not permit
The gravitational wave signature of such
gravitational time dilation to stop time alto-
mergers is a “ringdown,” a set of wiggles in
gether. He cites a similar situation that occurs
the signal that rise in frequency during the
within a cylinder of super-fluid helium, in
transition from two massive compact objects
which, at a certain vertical location, the speed
to a single one. The ringdown is predicted to
of sound attempts to go to zero. He points out
be slightly different for ECOs and UCOs than
that a phase transition in super-fluid helium
for black holes, and more precise observations
prevents this from happening, and he argues
of gravitational waves from mergers could re-
that a similar phase transition must occur in a
veal these differences. For ClePhOs, Cardoso
collapsing star, which will prevent the forma-
and Pani predict that the ringdown itself is the
tion of an event horizon. Protons and neu-
same as for black holes, but that a fraction of
trons must transition to leptons and mesons,
the gravity waves generated should be briefly
which must in turn transition to dark energy,
trapped between the object’s surface and its
and the repulsion generated by the dark ener-
photosphere. In this case, the characteristic
gy halts the collapse before an event horizon
ringdown signal would be followed by a se-
can form. Chapline’s work is but one example
quence of “echo” wiggles that would persist
of the many GR critics who have proposed al-
<
br /> for a few hundred milliseconds after the pri-
ternatives or modifications of GR that would
mary signal. The magnitude of these echoes
qualitatively change the stellar collapse sce-
and how fast they die out would depend on
nario and would prevent the formation of
the details of the ClePhO formation, permit-
black holes with event horizons. This raises
ting some discrimination between different
the question of whether these ideas and theo-
models.
ries, questioning the very existence of black
One group of physicists from Waterloo,
holes, can be tested by observation.
Canada and Tehran, Iran has analyzed the
three aLIGO events that were detected in
Recently, V. Cardoso and P. Pani of the Uni-
2015 in search of echo signals. Interestingly,
versity of Lisbon have proposed such an ob-
they obtained a positive indication of the
servational test. They first survey the various
presence of echoes. However, because of the
non-GR models of star collapse and divide the
noise present in the data, their result had a
resulting collapsed stars into: (1) exotic com-
statistical significance of less than three stan-
pact objects (ECOs) with radii smaller than a
dard deviations. A result must have six or
neutron star but larger than the photosphere,
more standard deviations to be considered a
(2) ultra-compact objects (UCOs) with radii
definite observation. Thus, it is inconclusive
near the photosphere radius, and (3) clean
but tantalizing. Improved analysis of this type
photosphere objects (ClePhOs) with radii
will probably have to wait for more events
only about 1.65% larger that the event horizon
and for new gravitational wave detectors to
radius r . All of these objects would have an
come online.
g
accretion disc and, based strictly on observa-
If such echo signals were actually observed
tion of their emissions of light and radio
with convincing statistical significance, the
waves, would be indistinguishable from a
observation would have major consequences
106
JOHN G. CRAMER
JANUARY/FEBRUARY 2018
for gravitational physics. It would be inter-
solute sensitivity to changes in arm length will
preted as falsifying GR and supporting rival
be an order of magnitude poorer than aLIGO.
non-GR theories that predict compact objects
Analog Science Fiction and Fact Page 29