Our Earth, our solar system, galaxy, and the universe is moving at incredible speeds and
the universe keeps expanding.
Can you tell us about these movements?
How is it possible that we are moving so fast in space and feel absolutely no movement,
no rush?
How come we are not hurled into space?
What we understand now in the general cosmology of our world is that the universe is in a
state of expansion and the rate of expansion is high so that, for example, our entire galaxy
relative to other galaxies is moving at tremendous speeds.
For example, something like a thousand kilometers per second is just the difference between
the speed of our galaxy and a nearby galaxy.
So these are tremendous speeds.
And then within our own galaxy, of course, we believe that our sun is orbiting the galaxy
at some high rate of speed.
And then at some tens of kilometers per second, the Earth is orbiting the sun.
So there's all these speeds involved.
And yet we feel so stationary.
And this has to do with the basic point that when the acceleration of an object is small,
then a natural experience of motion doesn't exist.
So if you're in a very well-made elevator in a tall building, what you'll find is in
the very well-made elevators, you can feel the initial acceleration as you're changing
your floor.
For much of the rest of the travel, you have no sense of movement except some sound.
Maybe the numbers are changing, but you have no sense of motion.
And then just at the end, when you're decelerating, you begin to sense it again.
So our bodies and our senses can detect acceleration, but they can't detect motion, just non-accelerated
motion.
So constant speed, they can't detect.
Now if my eyes can see and I'm driving in a car and I can see things go by, well, I have
a sense of motion, but no other sense than that.
In the case that we live on the Earth, of course, we do have all these speeds.
Our accelerations are small.
Our speeds are very large, but because we don't have a sense of acceleration, we don't
feel it.