Answer 3:
I’m glad to hear that you are excited about
physics! I will do my best to answer
your question, but it is a bit of a loaded
question as the nature of time and
whether or not it flows is a question
theoretical physicists debate even today.
For the sake of this question, let’s consider
“time” to be a “measurement of
change” which flows forward. In other words,
let’s accept an informal definition
of the flow of time based on how the vast majority
of us experience it.
The textbook definition of absolute zero (0
Kelvin) is “the temperature at which
all molecular motion stops.” Practically,
speaking this is unachievable because
cooling to an infinitely low temperature
requires an infinite amount of work.
Theoretically speaking, quantum theory is at odds
with this definition. You may
be familiar with the Heisenberg uncertainty
principle which states that the
uncertainty in momentum of a particle and
uncertainty in its position are related
by a constant value. In other words, if you
are quite sure there is at least one
atom in the universe, you are quite unsure about
its momentum and hence
quite unsure as to whether or not it is moving at
the quantum scale even
though from a classical perspective we have said
that all molecular motion has
“stopped.” Physicists call this phenomenon
“zero point energy.” So in that
sense “time” wouldn’t stop as particles would
continue to have some
uncertainty in momentum.
That said, if you could somehow survive in a
universe in which molecular
motion on the micro and macroscopic scales had
ceased or at least appeared
to have ceased, you wouldn’t be able to perceive
anything without molecular
movement. Light and sound are both carried via
particles which have
wavelengths in the micro, not quantum scale. Plus,
you own nervous system
relies on the motion of molecules to tell your
brain what you are feeling. So in
that sense perhaps your perception of the universe
(time included) would cease. Click Here to return to the search form.
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