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Let's assume space is curved in a way that it only appears vast and it's an irregular curvature. How would you be able to demonstrate if an object in a photogra

Let's assume space is curved in a way that it only appears vast and it's an irregular curvature. How would you be able to demonstrate if an object in a photograph is another cycle around the curvature? For instance, you could be seeing an already observed object at a different incoming angle and thus a trivial comparison would be defeated I'd think if this question is answerable you could also perhaps demonstrate there are no cycles or repetitions, even irregular ones. I don't know though, anyone that knows things care to opine? I'm assuming this is theoretically arguable, such as a proof by contradiction or something.

colechristensen 4y ago
We can do things to measure the curvature of the universe, everything so far points to complete flatness so if there is curvature and the universe is closed, the radius is much much larger than the observable universe as to make it appear “locally” flat, where “local” is something like 100 billion light years.
- pkaye 4y ago
  How did the measure the curvature of the universe?
  - mikeInAlaska 4y ago
    By looking at the remnant of the big bang -- measuring the power spectrum of the remaining cosmic microwave background energy, across large angles of sky.
    - kristopolous 4y ago
      Right, but how can you test assertions at that scale? In the same way that there's quantum physics, couldn't there be non-local or galaxy sized physics working in different ways? If not why? Rewriting the rules would probably solve a few mysteries. It sounds like an easy out
      - colechristensen 4y ago
        You look for physics that explains multiple things. A new law to explain each specific phenomena and only that one is probably wrong. You want laws with several unrelated testable consequences. Physics that boils down to “things are just the way we see them” isn’t much of an explanation. Physics that doesn’t change based on location, direction, scale, etc is important to look for. Easy outs probably aren’t helpful.
        kristopolous 4y ago
        Why isn't helpful? If it accounts for natural phenomena without mystery sauce then we're good. Our familiarity with the millennium long physics of parsec sized systems is rather limited and to presume there aren't factors at play that have variance at that size is rather presumptive. Has there been an effort to sincerely discard everything, observe only large scale celestial systems, then try to derive things all over again? You may just get classical models but then again, you might not. I'm familiar with that "shutup we know everything" response and not only do I find it thoroughly unconvincing but it's never been correct given a long enough timeline of scientific inquiry. The idea that we can demonstrate all the physics of the universe given the surface of a single planet sounds a little irrational. Look at the Voyager 1 AACS data for instance. Is the data incorrect or is it correct and things are just different in interstellar space?
        colechristensen 4y ago
        There have been plenty of attempts to modify gravity, general relativity, etc to explain the anomalous behavior at very large scales. None so far has come close to a satisfying solution which has testable effects and doesn’t introduce inconsistencies with already observed behavior. Clearly there is a gap between theory and reality, the best candidate right now is that there is a whole lot of matter out there which so far we can only observe through its gravitational effects and which does not interact with electromagnetism. Without much knowledge it’s easy to say “why don’t you just” but plenty of people have been trying and finding nothing that works or explains anything.

colechristensen 4y ago

We can do things to measure the curvature of the universe, everything so far points to complete flatness so if there is curvature and the universe is closed, the radius is much much larger than the observable universe as to make it appear “locally” flat, where “local” is something like 100 billion light years.

pkaye 4y ago
How did the measure the curvature of the universe?
- mikeInAlaska 4y ago
  By looking at the remnant of the big bang -- measuring the power spectrum of the remaining cosmic microwave background energy, across large angles of sky.
  - kristopolous 4y ago
    Right, but how can you test assertions at that scale? In the same way that there's quantum physics, couldn't there be non-local or galaxy sized physics working in different ways? If not why? Rewriting the rules would probably solve a few mysteries. It sounds like an easy out
    - colechristensen 4y ago
      You look for physics that explains multiple things. A new law to explain each specific phenomena and only that one is probably wrong. You want laws with several unrelated testable consequences. Physics that boils down to “things are just the way we see them” isn’t much of an explanation. Physics that doesn’t change based on location, direction, scale, etc is important to look for. Easy outs probably aren’t helpful.
      - kristopolous 4y ago
        Why isn't helpful? If it accounts for natural phenomena without mystery sauce then we're good. Our familiarity with the millennium long physics of parsec sized systems is rather limited and to presume there aren't factors at play that have variance at that size is rather presumptive. Has there been an effort to sincerely discard everything, observe only large scale celestial systems, then try to derive things all over again? You may just get classical models but then again, you might not. I'm familiar with that "shutup we know everything" response and not only do I find it thoroughly unconvincing but it's never been correct given a long enough timeline of scientific inquiry. The idea that we can demonstrate all the physics of the universe given the surface of a single planet sounds a little irrational. Look at the Voyager 1 AACS data for instance. Is the data incorrect or is it correct and things are just different in interstellar space?
        colechristensen 4y ago
        There have been plenty of attempts to modify gravity, general relativity, etc to explain the anomalous behavior at very large scales. None so far has come close to a satisfying solution which has testable effects and doesn’t introduce inconsistencies with already observed behavior. Clearly there is a gap between theory and reality, the best candidate right now is that there is a whole lot of matter out there which so far we can only observe through its gravitational effects and which does not interact with electromagnetism. Without much knowledge it’s easy to say “why don’t you just” but plenty of people have been trying and finding nothing that works or explains anything.