The Physics of Time
Even before Einstein, physics was
never really supportive of our common-sense ideas about time. Humankind has
long believed that the past and the future are very different, the one over,
done with, fixed, the other ahead, open, malleable. The past keeps gaining new
territory from the future across the boundary of the present. The calendar date
of tomorrow becomes that of today, then of yesterday. All this seems to force upon
us the conclusion that now is something that moves.
Science, with physics at its base, has
been a great success in explaining the phenomena of our world: thunder, billiards,
fire, elevators, airplanes, the ability of fish to swim and viruses to infect. What
did Newtonian physics have to tell us about this moving now? Nothing. The
equations of physics contain variables for time, t1, t2, even
t0, but no “now.”
With Einstein, physics stopped
being unhelpful regarding our shared sense that the now moves, and became hostile,
or at least unfriendly.
