- #1
tribdog
- 769
- 17
I just read the newest Scientific American. there is an article in it about 6 misconceptions about the big bang. let's see how you do? Can you answer the following 7 questions?
1)What kind of explosion was the big bang?
a. The big bang was like a bomb going off at a certain location in previously empty space.
b. it was an explosion of space itself
2)Can galaxies recede faster than light?
a. Sure they can special relativity does not apply to recession velocity.
b. of course not, special relativity forbids that.
3)Can we see galaxies receding faster than light?
a. no the light from those galaxies never reaches us
b. yes because the expansion rate changes over time
4)Why is there a cosmic redshift?
a.because space stretches all light waves as they propagate.
b. because receding galaxies are moving and exhibit a Doppler shift.
5)how large is the observable universe
a.the universe is 14 billion years old so has a radius of 14 billion light years
b. because space is expanding the observable universe has a radius about 3 times larger than 14 billion light years.
6)Do objects inside the universe expand too?
a. yes
b. no, the universe grows but coherent objects inside it do not.
7) Why won't Moonbear give me the time of day?
a. she doesn't have a watch
b. she has something called good taste
I'll post the answers in a few minutes unless I forget, in which case someone come find me in General discussion and remind me.
1)What kind of explosion was the big bang?
a. The big bang was like a bomb going off at a certain location in previously empty space.
b. it was an explosion of space itself
2)Can galaxies recede faster than light?
a. Sure they can special relativity does not apply to recession velocity.
b. of course not, special relativity forbids that.
3)Can we see galaxies receding faster than light?
a. no the light from those galaxies never reaches us
b. yes because the expansion rate changes over time
4)Why is there a cosmic redshift?
a.because space stretches all light waves as they propagate.
b. because receding galaxies are moving and exhibit a Doppler shift.
5)how large is the observable universe
a.the universe is 14 billion years old so has a radius of 14 billion light years
b. because space is expanding the observable universe has a radius about 3 times larger than 14 billion light years.
6)Do objects inside the universe expand too?
a. yes
b. no, the universe grows but coherent objects inside it do not.
7) Why won't Moonbear give me the time of day?
a. she doesn't have a watch
b. she has something called good taste
I'll post the answers in a few minutes unless I forget, in which case someone come find me in General discussion and remind me.