Is Everything Observed In The Universe Really There?

Question

Science tells us the universe is expanding and the stars and galaxies are moving away from each other at an unmeasureable rate. The photograpic images of all the stars and galaxies are a record of what was there in a long ago time equal to the objects distance away measured in light years, which is the distance light travels in one earth year. In other words if a star is 1000 light years away we're seeing the light and image of what the star looked like 1000 years ago, or if a galaxy is 20000 light years away we're actually seeing what it looked like twenty thousand years ago. If all these stellar objects are moving away from each other how do we know they're still there occupying that same area of space, or if they still exist at all? By this reckoning couldn't what we are seeing simply be the images of where a handful of galaxies were at various times and stages of their development, or even the footprints of just one galaxy's travels over billions and billions of years?

Answer 1

this is an interesting question, and i think what you describe is a fact scientists may underestimate.
The speed we observe distant objects to move away from us is not unmeasurable. From comparing specific stars in galaxies we have an idea about its distance, from its 'redshift' (sometimes blueshift) we know very precisly at what speed a distant object travels.
If you ask if an object is really there...
yes and no .. it WAS there, and there i think is something odd in our theories about the history of the universe.
Cause if someone observes a Quasar at a distance of 12 billion lightyears, i hear them calling .. 'the universe has an age of about 13 billion years, cause we can see a quasar at 12 billion' , or so. but HEY it is at 12 billion years PLUS the ammount of lightyears more distant, and probably look very different.
I never saw a calculation considering this, so i believe the universe is much older than 13.something billion years.

what we do is putting together a puzzle of small fragments.
beginning of how a star is born, how long it burns, how its life ends, and when. We collect samples as snapshots, measuring distances, but i'm afraid noone really cares about, that such an object with given redshift, has already travelled an enormous ammount of lightyears beyond its currently observed position.

since i never read about correctional calculations for the exact location, distance and (maybe) shape of a distant galaxy, i start having my doubts that it needs to have 'dark matter' to explain the galaxies unusual rotation, for example.

sooo when do we read about how it was calculated where a quasar for example sits ? i've not yet found such a calculation, but i probably digged not enough for it.

Answer 2

Hm. Yes and no.

You are right, we are just seeing images, and cannot say too much about the objects as they are now. But that doesn't really mean we know as little about them as some would imply.

For example, unless something REALLY goofy is going on, light generally follows the same rules everywhere. So let's think of some more local examples.

What would it take for a photo of a freeway packed with cars to actually be a photo of just one car? After the light left the car in the first position, we would have to move it to a new position where light could bound off it and get to your camera at the same time the first light arrived. This would mean not only moving the car at the speed of light, but also somehow avoiding all the light between position A and position B. Further, for the rays to get to you simultaneously, we could only move the car closer and not further.

Physics suggests that the first mechanic (moving at or faster than light) is impossible. And while we might imagine a car avoiding light, if it's EMITTING light like a star (maybe its headlights are on) this would seem to be impossible too. Worse yet, since the car has to be moving toward us, for it to seem like it's moving away it would have to be somehow altering the frequencies of emitted and reflected light more and more as we go. Which also is not like anything we have ever seen locally.

I'll grant that you have an interesting idea. But given what we know about the way things work, I'll still side with the idea that there's not only all the stuff we can see out there, but actually quite a bit of stuff (dark matter and dark energy) that we CAN'T see that's also out there.

Keep imagining, though! Without new ideas (and challenges to wrong ideas), almost all human endeavors end up falling flat!

Answer 3

Because we know approximately how long galaxies and stars live. If you see a galaxy that is 20,000 light years away and even though it takes 20K years for the light to hit you, it's still a short amount of time in terms of the lives of stars and galaxies. Most of the stars in said galaxy would still be there even though the galaxy may have moved. We can also predict where it is now based on what was around said galaxy. For instance, an alien on a planet in another galaxy several hundred million light years from our galaxy would be able to predict the Milky Ways fate.

Everything isn't really moving away from everything else (it is in the grand scheme), galaxies merge with other galaxies, etc. In fact, in a few billion years our Milky Way is going to collide with Andromeda. Locally, things are moving toward one another due to gravitational attraction, however, because space itself is expanding, in the grand scheme of things, everything is moving away from everything else because the "surface area" of space is getting larger

Answer 4

Yes, we are looking into the past. Many stars we observe may not exist anymore.
But seeing different images of the same objects in different times does not make much sense. There isn't an image recorder out there!

Answer 5

I could agree that technology is accustomed to a small proportion while it is composed of shown theory (authentic technology). The theoretical technology certainly has a protracted thank you to get closer The Bible. activity being the oldest e book in the Bible has some VERY thrilling shows that have in basic terms been born out as authentic by making use of technology millenium previous due. the human beings who've located technology upon a severe top, have made it into their chosen god, and that quite is a great disgrace. they are going to continually argue against the Biblical evidence because of the fact it brings them too on the brink of the admission of the life of a author. I desire you properly, yet to get those many human beings to admit that their many declarations of theoretical technology to be authentic is at appropriate very time eating; it quite is like banging ones head against a stone wall. for my section, i'm bored with attempting. There are even best scientists in maximum fields that believe in a author (and that i be responsive to you have informed 'em all this in the previous), and yet they do no longer choose to tutor. it quite is all what I call 'head banging'. Stephen Hawking speaks a load of nonsense for my section, yet many carry him in severe esteem - which would be their undertaking in the judgement.

Answer 6

It's not expanding at an immeasureable sped, in fact we are perfecting the measurement of the speed all the time.

Other than that, you are basically correct. Sure everything we are looking at could be gone. But the probability of that is sol low as to be absurd.

Answer 7

Good observation-We are in a time spot. Say there might be other observers at different time spots across the universe and I bet everyone would have a different map depending where they where.Some would have places that don't exist on our map and some places might be new on our map and not exist on theirs.

Answer 8

that's exactly right. we see where they were, not where they are, if they even still exist.

we can see whether they're moving towards or away from us, so we can more or less tell where they might be now, but it would still take so many thousands of years to see it.

Answer 9

What to do with a question that takes a rather glib direction of a rather detailed subject?

Answer 10

Good question here ! Well personally I think that the universe its a misterious place that we can study it for ever and still never get to really understand it...