Why should the universe succumb to our measurments

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The discussion centers on the challenges of measuring the universe's size and mass, particularly given that observations are limited to a certain horizon. Participants emphasize that while scientific models aim to help us understand the universe, they are inherently provisional and subject to change based on new data. The idea of using simple models, like a flat infinite universe, is accepted for its practicality in explaining observable phenomena, without claiming it represents the entire universe. There is acknowledgment of potential limits to our understanding, but optimism remains about future discoveries that could enhance our knowledge. Overall, the conversation reflects a balance between curiosity and the recognition of the complexities involved in cosmological measurements.
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I mean the universe as some mass, energy, what does it matter if our local universe is curved or flat, when the greater universe could be any thing other than what we measure.
How can we give the whole universe some size, mass, when we can only measure to some horizon.
Can we give the universe some size pre inflation.
If all this sounds nonsense, it is just a meandering of an inquisitive mind.
 
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wolram said:
I mean the universe as some mass, energy, what does it matter if our local universe is curved or flat, when the greater universe could be any thing other than what we measure.
How can we give the whole universe some size, mass, when we can only measure to some horizon.
Can we give the universe some size pre inflation.
If all this sounds nonsense, it is just a meandering of an inquisitive mind.

Exactly. The job of successive approximation by testable scientific models is to help us UNDERSTAND, and predict, and explain the universe we live in and see around us.

We are not concerned with the overall mass, or overall curvature, unless that would help us understand and predict what we see and what we live in and the natural world that the solar system and the Earth and life arose from.

Does knowing an overall mass number bring you closer to understanding? Well right off I cannot say, but it is not obvious to me that it does.

We can use a flat infinite model if it gives a good fit because it is simple and because it works. this does not mean to believe or claim that the whole universe is FLAT or INFINITE!
It just means that we get an amazingly good fit to the piece we can observe, using that simple type of model. If we discover small discrepancies eventually we can change the model, maybe introduce a tiny curvature and a large but finite circumference some day, but that is for later.

Everything is modest and provisional, the best we can do at present, subject to correction, no grandiose claims.

I think you have it right Wolram, it makes sense, does not sound like nonsense to me at least.
 
marcus said:
Exactly. The job of successive approximation by testable scientific models is to help us UNDERSTAND, and predict, and explain the universe we live in and see around us.

We are not concerned with the overall mass, or overall curvature, unless that would help us understand and predict what we see and what we live in and the natural world that the solar system and the Earth and life arose from.
I think that's a bit too simplistic.

We're going to find out what we can find out. We don't yet know how much we will be able to learn about the nature of our universe. There may be some hard limits on our understanding, due to the fact that we only see a fraction of the universe. But we can't yet be sure.

Personally, I'm content that we have a heck of a lot more to learn, and that experiments in the near future should significantly increase our understanding of our universe. There may be some limits that we can never move past, but that's just the way life is sometimes.
 
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