- #1
somedudeonline
- 11
- 0
Hi,
I joined this forum because I love learning new things about our universe and I often have questions like the one I'm about to ask. Also I would like to state that I haven't taken any physics classes so terms and advanced talk will be beyond me however, because I am so interested in this topic these things either come rather easily to me or I research until I figure it out.
So my question is about our expanding universe. I know that our universe is expanding and I know that it is space expanding and not the objects in space moving. I also know that certain areas of space are expanding faster than the speed of light.
What really confuses me is how space stretching has no effect on gravity itself. Every documentary I've ever seen explains a star in space as a marble on a sheet held tight in the air (the marble makes an indent in the sheet and if you place something much smaller next to it say a an air soft pellet it will fall in towards the marble). Well, with space stretching I imagine the star would be making a bigger impact on space because it is stretched thinner. I'm sure the simple explanation is that the marble and a sheet is simply an analogy and spacetime is actually very different but I still think this deserves an explanation. Does a star's gravity not have a bigger impact on spacetime because it's stretched (for lack of a better term) tighter meaning it's thinner but also more difficult to act on because it's tighter?
I joined this forum because I love learning new things about our universe and I often have questions like the one I'm about to ask. Also I would like to state that I haven't taken any physics classes so terms and advanced talk will be beyond me however, because I am so interested in this topic these things either come rather easily to me or I research until I figure it out.
So my question is about our expanding universe. I know that our universe is expanding and I know that it is space expanding and not the objects in space moving. I also know that certain areas of space are expanding faster than the speed of light.
What really confuses me is how space stretching has no effect on gravity itself. Every documentary I've ever seen explains a star in space as a marble on a sheet held tight in the air (the marble makes an indent in the sheet and if you place something much smaller next to it say a an air soft pellet it will fall in towards the marble). Well, with space stretching I imagine the star would be making a bigger impact on space because it is stretched thinner. I'm sure the simple explanation is that the marble and a sheet is simply an analogy and spacetime is actually very different but I still think this deserves an explanation. Does a star's gravity not have a bigger impact on spacetime because it's stretched (for lack of a better term) tighter meaning it's thinner but also more difficult to act on because it's tighter?