Zicoflex According to Einstein’s
Theory of Special
Relativity , the speed of
light can never change
—it’s always stuck at
approximately
300,000,000 meters/
second, no matter
who’s observing it.
This in itself is
incredible enough, given
that nothing can move
faster than light, but
it’s still very
theoretical. The really
cool part of Special
Relativity is an idea
called time dilation,
which states that the
faster you go, the
slower time passes
for you relative to your
surroundings. Seriously
—if you go take a ride
in your car for an hour,
you will have aged
ever-so-slightly less
than if you had just
sat at home on the
computer. The extra
nanoseconds you get
out of it might not be
worth the price of gas,
but hey, it’s an option.
Of course, time can
only slow down so
much, and the formula
works out so that if
you’re moving at the
speed of light, time
isn’t moving at all.
Now, before you go
out and try some get-
immortal-quick
scheme, just note that
moving at the speed
of light isn’t actually
possible, unless you
happen to be made of
light. Technically
speaking, moving that
fast would require an
infinite amount of
energy (and I for one
don’t have that kind of
juice just lying around).
9
Quantum
Entanglement
Alright, so we just
finished agreeing that
nothing can move
faster than the speed
of light—right? Well…
yes and no. While
that’s technically still
true, at least in theory,
it turns out that
there’s a loophole to
be found in the mind-
blowing branch of
physics known as
quantum mechanics.
Quantum mechanics, in
essence, is the study
of physics at a
microscopic scale, such
as the behavior of
subatomic particles.
These types of
particles are impossibly
small, but very
important, as they
form the building
blocks for everything in
the universe. I’ll leave
the technical details
aside for now (it gets
pretty complicated),
but you can picture
them as tiny, spinning,
electrically-charged
marbles. Okay, maybe
that’s kind of
complicated too. Just
roll with it (pun
intended).
So say we have two
electrons (a subatomic
particle with a
negative charge).
Quantum
entanglement is a
special process that
involves pairing up
these particles in such
a way that they
become identical
(marbles with the
same spin and charge).
When this happens,
things get weird—
because from now on,
these electrons stay
identical. This means
that if you change one
of them—say, spin it
in the other direction—
its twin reacts in
exactly the same way.
Instantly. No matter
where it is. Without
you even touching it.
The implications of
this process are huge
—it means that
information (in this
case, the direction of
spin) can essentially be
teleported anywhere in
the universe.
8 Light is
Affected by
Gravity
But let’s get back to
light for a minute, and
talk about the Theory
of General Relativity
this time (also by
Einstein). This one
involves an idea called
light deflection, which
is exactly what it
sounds like—the path
of a beam of light is
not entirely straight.
Strange as that
sounds, it’s been
proved repeatedly
(Einstein even got a
parade thrown in his
honor for properly
predicting it). What it
means is that, even
though light doesn’t
have any mass, its
path is affected by
things that do—such
as the sun. So if a
beam of light from,
say, a far off star
passes close enough
to the sun, it will
actually bend slightly
around it. The effect
on an observer—such
as us—is that we see
the star in a different
spot of sky than it’s
actually located (much
like fish in a lake are
never in the spot they
appear to be).
Remember that the
next time you look up
at the stars—it could
all just be a trick of the
light.
7 Dark
Matter
Thanks to some of
the theories we’ve
already discussed (plus
a whole lot we
haven’t), physicists
have some pretty
accurate ways of
measuring the total
mass present in the
universe. They also
have some pretty
accurate ways of
measuring the total
mass we can observe,
and here’s the twist—
the two numbers
don’t match up.
In fact, the amount of
total mass in the
universe is vastly
greater than the total
mass we can actually
account for. Physicists
were forced to come
up with an explanation
for this, and the
leading theory right
now involves dark
matter—a mysterious
substance that emits
no light and accounts
for approximately 95%
of the mass in the
universe. While it
hasn’t been formally
proved to exist
(because we can’t see
it), dark matter is
supported by a ton of
evidence, and has to
exist in some form or
another in order to
explain the universe.
6 Our
Universe is
Rapidly Expanding
Here’s where things
get a little trippy, and
to understand why,
we have to go back to
the Big Bang Theory.
Before it was a TV
show, the Big Bang
Theory was an
important explanation
for the origin of our
universe. In the most
simple analogy
possible, it worked
kind of like this: the
universe started as an
explosion. Debris
(planets, stars, etc)
was flung around in all
directions, driven by
the enormous energy
of the blast. Because
all of this debris is so
heavy, and thus
affected by the
gravity of everything
behind it, we would
expect this explosion
to slow down after a
while.
It doesn’t. In fact, the
expansion of our
universe is actually
getting faster over
time, which is as crazy
as if you threw a
baseball that kept
getting faster and
faster instead of
falling back to the
ground (though don’t
try that at home). This
means, in effect, that
space is always
growing. The only way
to explain this is with
dark matter, or, more
accurately, dark
energy, which is the
driving force behind
this cosmic
acceleration. So what
in the world is dark
energy, you ask? Well,
that’s another
interesting thing…
5 All
Matter
is Just
Energy
It’s true—matter and
energy are just two
sides of the same coin.
In fact, you’ve known
this your whole life, if
you’ve ever heard of
the formula E = mc^2.
The E is for energy,
and the m represents
mass. The amount of
energy contained in a
particular amount of
mass is determined by
the conversion factor c
squared, where c
represents—wait for
it—the speed of light.
The explanation for
this phenomenon is
really quite fascinating,
and it has to do with
the fact that the
mass of an object
increases as it
approaches the speed
of light (even as time
is slowing down). It is,
however, quite
complicated, so for the
purposes of this
article, I’ll simply
assure you that it’s
true. For proof
(unfortunately), look
no further than atomic
bombs, which convert
very small amounts of
matter into very large
amounts of energy.
4 Wave-
Particle Duality
Speaking of things
that are other things…
At first glance,
particles (such as an
electron) and waves
(such as light) couldn’t
be more different. One
is a solid chunk of
matter, and the other
is a radiating beam of
energy, kind of. It’s
apples and oranges.
But as it turns out,
things like light and
electrons can’t really
be confined to one
state of existence—
they act as both
particles and waves,
depending on who’s
looking.
No, seriously. I know
that sounds ridiculous
(and it’ll sound even
crazier when we get
to Number 1), but
there’s concrete
evidence that proves
light is a wave, and
other concrete
evidence that proves
light is a particle (ditto
for electrons). It’s
just… both. At the
same time. Not some
sort of intermediary
state between the
two, mind you—
physically both, in the
sense that it can be
either. Don’t worry if
that doesn’t make a
lot of sense, because
we’re back in the
realm of quantum
mechanics, and at that
level, the universe
doesn’t like to be
made sense of
anyway.
3 All
Objects Fall at the
Same Speed
Let’s calm things down
for a second, because
modern physics is a lot
to take in at once.
That’s okay—classical
physics proved some
pretty cool concepts
too.
You would be forgiven
for assuming that
heavier objects fall
faster than lighter
ones—it sounds like
common sense, and
besides, you know for
a fact that a bowling
ball drops more quickly
than a feather. And
this is true, but it has
nothing to do with
gravity—the only
reason this occurs is
because the earth’s
atmosphere provides
resistance. In reality,
as Galileo first realized
about 400 years ago,
gravity works the
same on all objects,
regardless of their
mass. What this
means is that if you
repeated the feather/
bowling ball
experiment on the
moon (which has no
atmosphere), they
would hit the ground
at the exact same
time.
2
Quantum Foam
Alright, break over.
Things are going to get
weird again.
The thing about empty
space, you’d think, is
that it’s empty. That
sounds like a pretty
safe assumption—it’s
in the name, after all.
But the universe, it
happens, is too
restless to put up with
that, which is why
particles are
constantly popping into
and out of existence all
over the place. They’re
called virtual particles,
but make no mistake
—they’re real, and
proven. They exist for
only a fraction of a
second, which is long
enough to break some
fundamental laws of
physics but quick
enough that this
doesn’t actually
matter (like if you
stole something from
a store, but put it back
on the shelf half a
second later).
Scientists have called
this phenomenon
‘ quantum foam,’
because apparently it
reminded them of the
shifting bubbles in the
head of a soft drink.
1 The
Double
Slit
Experiment
So remember a few
entries ago, when I
said everything was
both a wave and a
particle at the same
time? Of course you
do, you’ve been
following along
meticulously. But
here’s the other thing
—you know from
experience that things
have definite forms—
an apple in your hand is
an apple, not some
weird apple-wave
thing. So what, then,
causes something to
definitively become a
particle or a wave? As
it turns out, we do.
The double slit
experiment is the
most insane thing
you’ll read about all
day, and it works like
this—scientists set up
a screen with two slits
in front of a wall, and
shot a beam of light
through the slits so
they could see where
it hit on the wall.
Traditionally, with light
being a wave, it would
exhibit something
called a diffraction
pattern, and you would
see a band of light
spread across the wall.
That’s the default—if
you set up the
experiment right now,
that’s what you would
see.
But that’s not how
particles would react
to a double slit—they
would just go straight
through to create two
lines on the wall that
match up with the
slits. And if light is a
particle, why doesn’t it
exhibit this property
instead of a diffraction
pattern? The answer
is that it does—but
only if we want it to.
See, as a wave, light
travels through both
slits at the same time,
but as a particle, it can
only travel through
one. So if we want it
to act like a particle, all
we have to do is set
up a tool to measure
exactly which slit each
bit of light (called a
photon) goes through.
Think of it like a
camera—if it takes a
picture of each photon
as it passes through a
single slit, then that
photon can’t have
passed through both
slits, and thus it can’t
be a wave. As a result,
the interference
pattern on the wall
won’t appear—the
two lines will instead.
Light will have acted as
a particle merely
because we put a
camera in front of it.
We physically change
the outcome just by
measuring it.
It’s called the Observer
Effect, generally
speaking, and though
it’s a good way to end
this article, it doesn’t
even scratch the
surface of crazy things
to be found in physics.
For example, there are
a bunch of variations
of the double slit
experiment that are
even more insane than
the one I talked about
here. I encourage you
to look them up, but
only if you’re prepared
to spend the whole
day getting caught up
in quantum mechanics.