Two Interesting Questions
Here are two interesting questions you can ponder to exercise
your brainpower. The first: If you push on the end of a broomstick
or iron bar and move it, does the other end move at the same
time? Now that may not seem too interesting at first glance,
but it directly leads to the second: Can anything move faster
than the speed of light? The answers to these could have profound
consequences.
Don't worry if you didn't do well in your physics classes.
Simple logic and a few facts will suffice for playing around
with these concepts for now. We'll start with the fact that most
physicists believe that nothing can move faster than the speed
of light. That speed, by the way, is about 299,792,458 meters
or 186,000 miles per second.
It certainly seems that if you were to push or pull one end
of a long bar that the other end would move at the same time.
But imagine an iron bar that is ten light years long, spanning
the distance between here and another planet that has intelligent
life. If you push or pull this end does the other end move at
the same time? If so you could transmit information through a
series of movements, using Morse code, for example. You could
transmit several sentences in a matter of seconds or minutes,
instead of the ten years it would take to do so using radio waves
or light signals.
But this is contrary to the widely accepted view that nothing
can move faster than the speed of light. Although the bar itself
would move slowly, the information would be transmitted those
billions of miles in just seconds - much faster than light or
radio waves can travel (in fact, even the light of our own sun
takes over eight minutes to get here). So can the other end of
the bar move at the same time?
Obviously either our "common sense" idea that the
whole bar would move at the same time is wrong (perhaps the motion
is transmitted as a wave through the bar), or the theory that
nothing can move faster than light is wrong. If the other end
of that bar did move simultaneously, it presents us with some
interesting scenarios. Had we been watching television transmissions
from the other planet, for example, they would take ten years
to arrive, but a person with an "iron bar information transmitter"
(and a friend on the other end) could predict years in advance
what was coming.
Of course the iron bar itself is not realistic, but something
using the same principle was once proposed. It was suggested
by one scientist that the effect of gravity was instantaneous
across great distances, just like that iron bar. If we developed
a device for measuring the gravitational effect of a large item
(perhaps a chunk of iron) at great distances, then we could also
manipulate the movement of that item to transmit information
(by way of the measuring of those movements) more quickly than
the speed of light.
Almost certainly there are flaws in these ideas that will
be pointed out by those with a better understanding of physics.
But these are still interesting questions. In fact, I have to
throw out my own questions about the speed of light, which some
have tried to answer, but not very successfully (maybe due to
my own lack of understanding?)
Moving Faster Than The Speed Of Light
The speed of all things is relative. We say that a car is
moving at 100 kilometers per hour, for example, but that is only
in relation to the surface it travels on. Since the Earth that
it is on moves at 1670 kilometers per hour, the car could also
be said to moving at 1770 or 1570 kilometers per hour, depending
on whether it is going east or west, and assuming it is driving
near the equator. But the planet is also moving - with the car
on it - at 107,000 kilometers per hour around the sun. The sun
is part of a solar system moving in relation to other systems,
of course.
So what is the "real" velocity? There is no such
thing. We use the relationship that is most relevant for our
purposes (100 kilometers per hour in relation to the road if
we are looking at the speed limit signs).
Now, when someone with more knowledge of physics tells me
that nothing can move faster than the speed of light, I ask if
something could (at least in theory) move at 60% of the speed
of light. They universally answer yes. I then suggest that if
a space ship were to pass over the Earth at 60% of the speed
of light and another were to do the same in the opposite direction,
that in relation to each other they would be going at 120% the
speed of light - which is supposed to be impossible.
The weaker physicists refer back to the 60%, forgetting that
this is only in relation to the Earth. But there is no universal
reference point in the universe from which we can measure the
velocity of all things. It is all relative. You could measure
in relation to the sun, another star, or from some point between
stars at the edge of the galaxy. These are arbitrary, and any
can be used.
So if we choose to measure the velocity of the one spaceship
in relation to the other, it seems logical that it is moving
faster than the speed of light. This is similar to how two cars
moving past each other in opposite directions, each traveling
at 100 kilometers per hour, would be going at 200 kilometers
per hour in relation to each other.
By the definitions used and simple logic, it seems that it
is possible to go faster than the speed of light. These are interesting
ideas, but I am sure that I will get several emails telling me
how completely wrong I am. I don't doubt that I am wrong, but
I do hope that someone will actually be able to explain why in
a language that I can understand.
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