Could our position in the universe affect our perceptions of the expansion?
Also couldn't our position in the universe be affecting our perceptions of the expansion say like someone being in the bleachers of an expanding arena as opposed to someone at the pitcher's mound?
It's possible that we could have been given a universe that looks very different for different observers. But this doesn't appear to be the case. In cosmology, we assume that the universe is both homogeneous and isotropic (looks the same everywhere on large scales, the structure has no preferred direction). This appears to be true if you look at the distribution of galaxies (or gamma ray bursts, or anything that we can see out to large distances) on the sky, it looks pretty uniform across the entire sky (look at this slice of the sky from the APM Survey)
So while we can't go to another galaxy and measure the expansion of the universe there and compare it to what we measure here, we have pretty good reason to believe that the universe "looks the same" wherever you are, so the expansion should work the same way.
Get More 'Curious?' with Our New PODCAST:
- Podcast? Subscribe? Tell me about the Ask an Astronomer Podcast
- Subscribe to our Podcast | Listen to our current Episode
- Cool! But I can't now. Send me a quick reminder now for later.
How to ask a question:
If you have a follow-up question concerning the above subject, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.
This page has been accessed 20284 times since September 30, 2002.
Last modified: October 1, 2002 9:07:22 AM
Ask an Astronomer is hosted by the Astronomy Department at Cornell University and is produced with PHP and MySQL.
Warning: Your browser is misbehaving! This page might look ugly. (Details)