Expansion or repulsion

  • B
  • Thread starter thetexan
  • Start date
  • #1
250
8
I was playing around in the kitchen today. You know how when you drop some pepper in a calm glass of water the flakes instantly seem to repulse from each other and expand over the entire surface? I believe this is due to surface tension in the skin of the water.

Could expansion be possibly caused by some unknown tension in the space/time that causes everything to repulse from each other in an effort to equalize that tension?

tex
 

Answers and Replies

  • #2
PeterDonis
Mentor
Insights Author
2020 Award
32,988
11,462
Could expansion be possibly caused by some unknown tension in the space/time that causes everything to repulse from each other in an effort to equalize that tension?
First of all, tension in a medium is not the same thing as surface tension--the latter, as its name implies, only happens at a surface, i.e., at the boundary between one medium (in this case, the water) and another (in this case, the air). Spacetime doesn't have a boundary with anything else.

The concept of a cosmological constant, which is one possible explanation for the accelerating expansion of the universe (it's one possible kind of dark energy, which is the general term for whatever it is that is making the expansion accelerate) can sort of be thought of as something like empty space having a tension. But, as just noted, this only accounts for the acceleration of the expansion; it doesn't account for the expansion itself.

Anyway, the behavior of objects in our expanding universe isn't the same as the behavior the flakes on the surface of the water. The flakes move apart until tension is equalized, then stop. Objects in our expanding universe continue to move apart.
 

Related Threads on Expansion or repulsion

  • Last Post
Replies
6
Views
758
Replies
13
Views
3K
Replies
27
Views
4K
Replies
7
Views
989
  • Last Post
3
Replies
54
Views
5K
  • Last Post
Replies
1
Views
1K
  • Last Post
4
Replies
96
Views
18K
Replies
1
Views
856
  • Last Post
Replies
6
Views
3K
Top