Rubber sheet analogy - density change

  • Thread starter Pjpic
  • Start date
234
1
When the rubber sheet with the bowling ball in it stretches, the density of the rubber is lowered as the rubber molecules become more widely separated by empty space. Are there particles of space time(?) that are similarily separated by more empty space when when the amount of nearby mass(?) changes?
 

DaveC426913

Gold Member
18,262
1,866
When the rubber sheet with the bowling ball in it stretches, the density of the rubber is lowered as the rubber molecules become more widely separated by empty space. Are there particles of space time(?) that are similarily separated by more empty space when when the amount of nearby mass(?) changes?
No. You are stretching the rubber sheet analogy too far.

(:biggrin:)
 
234
1
No.

If the amount of mass changes space time, what is changing? If there is a measurement and the numbers are changing, what whole does each interger represent?
 

A.T.

Science Advisor
9,660
1,509
When the rubber sheet with the bowling ball in it stretches, the density of the rubber is lowered as the rubber molecules become more widely separated by empty space. Are there particles of space time(?)
The rubber sheet usually represents only space, and is therefore misleading. See post #4 in this thread:
https://www.physicsforums.com/showthread.php?t=286926
If the amount of mass changes space time, what is changing?
The distances along space-time dimensions (the metric) change. Space-time is "streched" but there are no "particles of space time" in the model. It is a smooth manifold with a intrinsic curvature, and free falling objects are moving on geodesic paths.
 

Related Threads for: Rubber sheet analogy - density change

  • Posted
Replies
6
Views
833
  • Posted
2 3
Replies
56
Views
15K
Replies
10
Views
1K
Replies
3
Views
2K
  • Posted
Replies
5
Views
2K
  • Posted
Replies
3
Views
551
Replies
62
Views
1K

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving
Top