- #1
ronald_dai
- 36
- 1
I am a philosopher with little bakcground knowledge in physics. The GRB news brought me here. Thanks to the help from Marcus and DaleSwanson, now I know much better about the universe expansion. I am not as good at math as most of you here are, but my hobby is drawing a big picture whenever I learn something new. I have drawn a picture about this universe expansion as follows and welcome any criticism or comments from you:
Our universe locates in a 4-dimensional spacetime sector and started from a BIG BANG with a total mass M, after the BIG BANG, the universe started to expand "OUTWARD" in the 4-dimensional spacetime under its own inertia...
Since each part of the 4-dimensional body is moving "OUTWARD", there are different relative receding velocities between different parts. This is just like when a 3-d ball explodes, while all exploded pieces flying outward, there are relative velocities between them...
Even though, the "OUTWARD" velocity of every celestial object is smaller than the speed of light, due to the great size of this 4-dimensional body, the relative receding velocities between different celestial bodies could be greater than the speed of light...
Based on this understanding, we could imagine that the size of the 3-dimensional surface of this 4-dimensional body should grow at a 2/3 power law if the size of the 4-dimensional body is increasing linearly with time (if the volume of a 3-dimensional body grows linearly with time, the radius should grow at a 1/2 power law, therefore, we might imagine that the size of this 3-d surface should grow at a 2/3 power law)...
Based on some astronomic observational data, in order to have the momentum as calculated by scientists so far, the Universe should contain some extra Mass which is called Dark Mass, otherwise the universe might not have such a big momentum...
At least up to this moment, the universe is still expanding "OUTWARD" under its own initial exploding momentum, but no body knows yet whether the expansion would stop someday and start to contract...
...
That's the whole picture I have drawn from what I have learned since yesterday...There is one major unclear point to me: If the universe is a 3-d spatial body, then I could clearly know the meaning of "OUTWARD", and I would know the universe would be a sphere, but with time as one dimension, it is hard for me to think about the meaning of "OUTWARD" and I guess the universe body might not be a 4-dimensional sphere, right? ...Besides, if I am right with the big picture, then we should be able to calculate the total volume of the universe as long as we know the total Mass M, right?
Welcome any criticism and comments...thanks
Our universe locates in a 4-dimensional spacetime sector and started from a BIG BANG with a total mass M, after the BIG BANG, the universe started to expand "OUTWARD" in the 4-dimensional spacetime under its own inertia...
Since each part of the 4-dimensional body is moving "OUTWARD", there are different relative receding velocities between different parts. This is just like when a 3-d ball explodes, while all exploded pieces flying outward, there are relative velocities between them...
Even though, the "OUTWARD" velocity of every celestial object is smaller than the speed of light, due to the great size of this 4-dimensional body, the relative receding velocities between different celestial bodies could be greater than the speed of light...
Based on this understanding, we could imagine that the size of the 3-dimensional surface of this 4-dimensional body should grow at a 2/3 power law if the size of the 4-dimensional body is increasing linearly with time (if the volume of a 3-dimensional body grows linearly with time, the radius should grow at a 1/2 power law, therefore, we might imagine that the size of this 3-d surface should grow at a 2/3 power law)...
Based on some astronomic observational data, in order to have the momentum as calculated by scientists so far, the Universe should contain some extra Mass which is called Dark Mass, otherwise the universe might not have such a big momentum...
At least up to this moment, the universe is still expanding "OUTWARD" under its own initial exploding momentum, but no body knows yet whether the expansion would stop someday and start to contract...
...
That's the whole picture I have drawn from what I have learned since yesterday...There is one major unclear point to me: If the universe is a 3-d spatial body, then I could clearly know the meaning of "OUTWARD", and I would know the universe would be a sphere, but with time as one dimension, it is hard for me to think about the meaning of "OUTWARD" and I guess the universe body might not be a 4-dimensional sphere, right? ...Besides, if I am right with the big picture, then we should be able to calculate the total volume of the universe as long as we know the total Mass M, right?
Welcome any criticism and comments...thanks