Page 293 - (DK) I Can’t Believe It! 2

TRUE OR FALSE? 291
Einstein figured out
that if you traveled faster FAST FACTS
than light, you would
go back in time—but
his theory of relativity
showed that accelerating ANSWER
something beyond that
speed is impossible. TO EVERYTHING

QUANTUM COMPUTERS
WILL HAVE THE…
Extremely powerful quantum computers will
According to the theory be able to solve difficult problems very quickly.
of relativity, time runs They will do so by considering all the possible
at different rates in answers simultaneously before coming up
different situations. with one informed solution.
There is no “absolute”
rate of time—it is YOU CREATE A
relative. The same is If you travel into space at
true of distances. nearly the speed of light for a PARALLEL
few years, and then return to
Earth, you will find that much UNIVERSE
more time has passed back
home than it has for you. EVERY TIME
YOU MAKE
A DECISION

That’s true according to one interpretation of
quantum theory. For each important decision
or action you take, there is another universe
in which you do something differently. The
parallel versions of you also make decisions,
which results in even more universes. Since we
can’t interact with parallel universes, we may
never know for sure whether or not they exist.
The most accurate clock GRAVITY IS
on Earth is a type of atomic
clock called strontium lattice. THE LAST
It won’t lose a second PIECE IN
in five billion years. THE COSMIC
PUZZLE

OF CREATION

Where on According to quantum theory, forces are
carried by subatomic particles. Scientists have
Earth do discovered the particles that carry each of
clocks run the forces—except gravity. If they exist, the
the fastest? particles that carry gravity, dubbed “gravitons,”
will be extremely hard to detect.

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