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TIME TRAVEL

Traveling through time may seem like science fiction, but some scientists think that there
are some serious science facts in the idea: from Einstein, whose theory of relativity shows
that time is not fixed, to quantum physicists, whose study of subatomic particles point to
the possibility of parallel worlds. So, with a little help from a cosmic string or a wiggly
wormhole, will we be boldy going where no others have gone before? Only time will tell.

COSMIC STRINGS TIPLER CYLINDER
Grab onto a cosmic string American astronomer Frank Tipler’s idea for
and use its immense a time machine involves taking a dense chunk
gravitational pull to travel of matter and rolling it into an infinitely long,
at incredible speeds. These fast-spinning cylinder. If a spaceship followed
stringlike objects were the right spiral course around the cylinder,
probably formed it could emerge thousands of years from its
in the early stages of starting point. Of course, building an infinitely
the universe, and may long cylinder would be quite a challenge!
line the entire universe.
Their gravitational force
is so strong that it
could bend space
and time to allow
time travel.

LoOKS LIKE ARRIVALS: PAST
YOU’VE GOT the UP TO DEPARTURES
BUBONIC PLAGUE.
QUARANTINE PLAGUE CARRIERS
Diseases and infections are endlessly
mutating or changing, so a vaccine that
protects you against typhoid fever
today wouldn’t necessarily work if
you traveled back to Roman times.
There’s also a strong chance that you
hunting dinosaurs would carry nasty bugs back with
was great. I shot you that could wipe out your ancestors.
one that had wings
like a bird.
GOODBYE, HUMANS

what’s Over millions of years, shrewlike
a bird? creatures living at the time of
the dinosaurs evolved into
mammals and eventually into
humans. Now imagine what would
happen if some clumsy oaf traveled
back in time and obliterated our
furry ancestors. You’ve guessed
it—no shrews, no humans.

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