0.00001 0.0001 0.001 0.01 0.1 1 10 100 1,000 10,000
5 hours
Earth
40 minutes
Pluto
7 months
Proxima
Centauri
3 years
Fomalhaut
628 years
89 years 1,200 years
Kepler-22b
Years (logarithmic scale)
8,400 years
Gem
Cluster
From a resting reference frame 4 years 25 years
From the traveler’s reference frame
34 ASTRONOMY • JUNE 2015
as if they are still two sides of one coin, aware of and in tune with
their other half ’s identity without any lag across space and time.
This strongly suggests that the gap between bodies is not real on
some level. Emptiness is not what we assumed it to be. If even distant
objects are in contact, what does this say about space or separation?
And wait, it gets worse. Einstein’s relativity shows that space is
not a constant and therefore not inherently substantive. High-speed
travel makes intervening space dramatically shrink. Thus when we
step out under the stars, we may marvel at their distances and the
universe’s vast spaces. But it has been shown repeatedly that this
seeming separation between ourselves and anything else is subject to
point of view — what Einstein called a “reference frame” — and
therefore has no inherent bedrock reality. This doesn’t by itself
negate space but merely makes it tentative.
If we lived on a world with a very strong gravitational field or
traveled outbound at a high speed, those stars would lie at entirely
different distances. If we headed toward the star Procyon at 99 per-
cent of light-speed, we would find that it was actually less than 2
light-years away, not the 11 light-years we’d previously measured it to
be. If we crossed a living room 21 feet (6 meters) in length going at
that speed, every instrument in our perception would show that it’s
actually now 3 feet (1m) long. And if we could move at 99.9999999
percent of light-speed, which is perfectly allowable by the laws of
physics, the living room would now be barely larger than the period
at the end of this sentence. Space would have changed to nearly
nothing. Where, then, is the supposedly trustworthy space matrix,
the gridwork within which we observe the stars and galaxies?
In the mind’s eye?
More abstractly, we could even wonder whether space has an objec-
tive reality or is merely our minds’ efforts to give order to what we
see. Is space part of the mental logic of the animal organism, the
software that molds sensations into multidimensional objects?
Albert Einstein had strong feel-
ings against quantum entangle-
ment (and indeed, quantum
mechanics as a whole), which he
called “spooky actions at a dis-
tance.” He firmly rejected the
idea that physics might not be
“local” (objects must be in physi-
cal proximity in order to affect
each other) or “real” (meaning
here that objects have a prede-
termined state prior to being
measured). If locality did not
exist, then Einstein’s own laws of
relativity were flawed because
they were incompatible with
information being transmitted
instantaneously across space. If
reality did not exist, then ...
frankly this idea was simply
deeply disturbing. It was easier to
believe in “hidden variables,” or
the idea that, contrary to quan-
tum laws, particles have a “true”
state that is revealed, rather than
determined, by observation.
In 1935, Einstein, along with
Boris Podolsky and Nathan
Rosen, proposed the EPR
Paradox. They claimed that the
absurdity of entanglement —
twinned particles randomly
choosing complementary states
and then communicating that
information across immeasurable
space — must prove quantum
theory flawed, or at best incom-
plete. In 1964, John Bell contin-
ued their thought experiment,
developing testable hypotheses
(Bell’s inequalities) that would
prove we live in a classically
determined universe. So far,
experiments have consistently
disproven Bell’s inequalities,
negating Einstein’s paradox and
showing that the universe we live
in does not require local realism.
Weird as it sounds on a human
scale, the universe is measurably
unreal on a fundamental level.
And yet there is one loophole
left to close in Bell’s theorem,
probably the weirdest yet: free
will. Bell’s theorem suggests that
quantum mechanics could be dis-
proven if humans lack free will. If
we are preprogrammed in the
observations we make, then
entangled particles aren’t
required to perform any “spooky
actions.” The universe knows
what we will measure before we
start. Not all scientists put stock in
this interpretation, but others are
hard at work finding ways to test
this last holdout for a classical
world. Spooky. — Korey Haynes
ENTANGLEMENT STANDS
Time is relative at 99 percent the speed of light
10
0
10
3
10
–2
10
–4
10
6
How long does it take to get there?
If you could travel near light-speed,
what you measure as a quick jaunt
would be a lengthy wait for your
friends back home. ASTRONOMY: ROEN KELLY
Earth Baltimore’s inner harbor Human Fingertip Skin