Page 152 - The Perpetrations of Captain Kaga

Breaking the Grapefruit Connection
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“You know,” said Lugo, squinting at the diagram. “It’s hard to
imagine three dimensions squashed into one. How can we be looking
down at a path in spacetime? You can’t really perceive more of time
than just the present instant.”
“That’s true,” said Kaga. ‘‘We’re taking an imaginary fifth-
dimensional viewpoint, just as we actually take four-dimensional
looks at three-dimensional objects through stretches of time. In fact,
the past and future areas are hyperspheres, expanding rapidly in
spatial volume as they recede in time from the present. If I struck a
match right now, in one second the first light waves from it, if
unimpeded, would describe a sphere whose radius is 186,000 miles.”
“I see,” said Lugo. ‘‘Since no material body can approach the speed
of light, a person could never get outside the hypersphere of light that
began at his birth.”
“Right, and for any given point in spacetime, or present location,
there is a similar boundary to possible past locations. We are limited
in where we can go and where we could have come from—or were,
until Pamplemousse came along.”
“You mean…”
“Wait a minute, I’m getting to it. Now, what about the third area of
spacetime around a point? It’s there, but can’t be gotten to,
communicated with, or known about. It is inaccessible because
something would have to travel faster than light to connect with a
point outside its hyperspheres of possible past and future. Although
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