The Expanding Universe -- Why and How We Know It Is Expanding

How does science work? And what's all this about quantum mechanics?

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-1-
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by -1- » Fri Apr 19, 2019 4:38 pm

gaffo wrote:
Mon Apr 15, 2019 3:10 am
-1- wrote:
Mon Apr 15, 2019 2:29 am
gaffo wrote:
Mon Apr 15, 2019 12:02 am
I understand what your point is but think you are in error, for the "dots" are "expanding too!", i also noted your "the geometrical proof" above. space expansion doe not have to do with geometry, since the "dots and the spaces between the dots" are ALL Expanding, as are the measuring stick to measure them!
The only thing to consider is that the speed of distancing is commensurate with the distance between two points.

This can only happen if the object (not space) called "known universe" or "observable universe" is uniformly expanding. No other explanation has been proposed (to my knowledge) to explain the phenomena with reason.
don;t follow your argument - objects and space are expanding (everything is - including the measuring sticks)
The argument is that the speed of two points in opposite directions is commensurate with the distance between them.

The thought experiment I proposed in the opening post shows that if something measurable in expansion was expanding, then that would result in the speed between any two pairs of points would be commensurate with the distance between them. My thought experiment needed a measuring stick. And then when you realize that in a system where points speed from each other at a speed commensurate with the distance between them, it can only be so if it the system is expanding, uniformly, then you can throw away the measuring stick and declare that any system where any two points speed away with speeds commensurate with the distance between them, is an expanding space=system.

This you have to read very, very carefully, Gaffo. I can't explain it in any other way. If you are still baffled, then I suggest you either think about it for a long time, or ask someone else to explain it to you. I've given it my best shot.

Logik
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Logik » Fri Apr 19, 2019 4:41 pm

-1- wrote:
Fri Apr 19, 2019 4:30 pm
The code is good, but it is not perfect. It is not perfect because it is set up for failure, recognizable failure, and that is unavoidable, inasmuch as some conversations and topics of discussions have a definite, satisfactory, and final ending, which is exaclty what the code has been created to avoid.
That's ironic. Being well aware of the epistemic problem of criterion, would you say that you known which discussions (e.g which questions) have a definite, satisfactory and final ending; and which don't?

It's almost as if you are appealing to the "decidability" criterion in logic. https://en.wikipedia.org/wiki/Decidability_(logic)
In logic, a true/false decision problem is decidable if there exists an effective method for deriving the correct answer
So which one is the correct answer?

A. The expansion of the universe has a definite, satisfactory and final ending,
B. The expansion of the universe doesn't have a definite, satisfactory and final ending.

Atla
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Atla » Fri Apr 19, 2019 5:44 pm

-1- wrote:
Fri Apr 19, 2019 4:30 pm
There were times when I had thought Logik was a computer program written by some ambitious student of philosophy, computer science or math, and the writer was trying out the capabilities of his code on this site.

Obviously there is some background factual material stored in the program, which is quoted at more right than at wrong times. The bridging from one set of thought to another you, Atla, explain with the person's inability to understand; I explain it with the code-writer's dilemma how to make his program continue and keep its converstation partner engaged.

It is smoke and mirrors. When the code senses danger that the conversation is coming to an inescapable and mainly FINAL conclusion, then it raises some "smoke" and creates "mirrored" images that can be taken for reality by the less prepared thinker. The smoke the program creates is invariably a new concept just thrown in, normally in the shape or form of the semantic construct "yeah, what you are saying is xxxx" where xxxx is an obscure-to-laymen but a well-known thought to experts. The experts (which I am not) can easily identify the concept, and they may decree it valid or invalid at the time it is brought up. We, and mainly I, however, am not an expert, and let the code (a.k.a. Logik) carry on in this new vein in the conversation.

The code is good, but it is not perfect. It is not perfect because it is set up for failure, recognizable failure, and that is unavoidable, inasmuch as some conversations and topics of discussions have a definite, satisfactory, and final ending, which is exaclty what the code has been created to avoid.
Well compared to Logik, even I'm an "expert" on computers and information (I formally studied computer sciences for years) and can tell you that he doesn't have a fucking clue what he's talking about. The "expert talk" he deceives most people with here is simply a narcissistic bluff (he just wants to be superior and hurt people, because that's what he enjoys). His expert talk is almost always unrelated to the topic, totally inappropriate, out of context, and even then he manages to write tons of things that are factually simply not true. I don't think he understands any of it.

Same seems to be the case with his claims about being an expert logician, just a bluff. He doesn't even understand basic logic.

I like your idea about him being a software. :) I'm not sure whether he would pass a Turing test, but thanks to the efforts of those who actually do know a thing or two about computers, I'm confident that in a few decades we'll have AIs that will mimic humans a lot better than Logik does. :)

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Logik » Fri Apr 19, 2019 6:15 pm

Atla wrote:
Fri Apr 19, 2019 5:44 pm
Well compared to Logik, even I'm an "expert" on computers and information (I formally studied computer sciences for years) and can tell you that he doesn't have a fucking clue what he's talking about.
:lol: :lol: :lol: :lol: :lol:

So you equate expertise with oratorship?

The Green Lumber Fallacy: The Difference between Talking and Doing

If you "formally studied computer science" and you can't relate to that which I am demonstrating - you got scammed. Get your money back - sue if you have to.

Here's some evidence that you got robbed. You don't even grasp basic systems theory.
Atla wrote:
Sun Apr 14, 2019 2:01 pm
Not sure what you are commenting on, I only said that an expanding infinity is logically impossible. Because an infinite universe can't get any bigger, it's already infinite. In fact any change in "size" or any change at all is logically impossible.
https://en.wikipedia.org/wiki/Open_syst ... ms_theory)
An open system is also known as a constant volume system or a flow system.
A closed system contains limited energies.
In the natural sciences an open system is one whose border is permeable to both energy and mass
So I am sure you will be telling us any moment now how you think "the universe" is an open-but-closed, expanding-but-infinite system ;)
Last edited by Logik on Fri Apr 19, 2019 7:24 pm, edited 6 times in total.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Cerveny » Fri Apr 19, 2019 7:07 pm

Consider please, that Universe does not “expand” but grows, like a crystal does or at least like as a cactus does. You certainly ask from what substrate? I believe, from the Future. It is the other (unfixed/timeless/not ordred yet) phase of the reality. It was here even before the begining. I promise it is the last time I am writing about....:(

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo » Sun Apr 21, 2019 12:43 am

-1- wrote:
Fri Apr 19, 2019 4:38 pm
gaffo wrote:
Mon Apr 15, 2019 3:10 am
-1- wrote:
Mon Apr 15, 2019 2:29 am


The only thing to consider is that the speed of distancing is commensurate with the distance between two points.

This can only happen if the object (not space) called "known universe" or "observable universe" is uniformly expanding. No other explanation has been proposed (to my knowledge) to explain the phenomena with reason.
don;t follow your argument - objects and space are expanding (everything is - including the measuring sticks)
The argument is that the speed of two points in opposite directions is commensurate with the distance between them.

The thought experiment I proposed in the opening post shows that if something measurable in expansion was expanding, then that would result in the speed between any two pairs of points would be commensurate with the distance between them. My thought experiment needed a measuring stick. And then when you realize that in a system where points speed from each other at a speed commensurate with the distance between them, it can only be so if it the system is expanding, uniformly, then you can throw away the measuring stick and declare that any system where any two points speed away with speeds commensurate with the distance between them, is an expanding space=system.

This you have to read very, very carefully, Gaffo. I can't explain it in any other way. If you are still baffled, then I suggest you either think about it for a long time, or ask someone else to explain it to you. I've given it my best shot.
I don't understand your view, nor do i know anyone to help me understand.

i'm ok with be being ignorant, and thank you for reply and also welcome clarification of your views -though i might not have the brains to understand it (not being flippant - i;m smart, above age,but not far abv avage - prob 120 or so IQ). just saying here.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo » Sun Apr 21, 2019 12:49 am

Atla wrote:
Fri Apr 19, 2019 5:44 pm

Well compared to Logik, even I'm an "expert" on computers and information (I formally studied computer sciences for years) and can tell you that he doesn't have a fucking clue what he's talking about.
lol! thanks for the laugh, never a CS major, all it know is self taught making my PC's and installing Slackware in the mid 90's - and had/used OS2-Warp (what a great OS - IBM just pissed that one away - whatelse is new WRT to IBM).

thanks for the laugh! ;-).

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by -1- » Sun Apr 21, 2019 1:10 am

Cerveny wrote:
Fri Apr 19, 2019 7:07 pm
Consider please, that Universe does not “expand” but grows, like a crystal does or at least like as a cactus does. You certainly ask from what substrate? I believe, from the Future. It is the other (unfixed/timeless/not ordred yet) phase of the reality. It was here even before the begining. I promise it is the last time I am writing about....:(
I used to know a guy in Budapest who wrote a short story about pyramids. The pyramids of the pharaos. The great ones. The huge ones.

In his story someone invents the time machine in the future, when they have figured out the technology how to build pyramids. Then that guy goes back to the past, to the time of pharaohs, and he directs the locals how to build pyramids. He does not teach them the skill, but just micromanages them to build those huge structures.

Then he gets killed by some irate person, forgot for what reason. So with his death, which was in the past, his future self does not discover how to build pyramids.

But the pyramids had already been built with his direction. Except he never gets born again, and the invention does not occur to anyone else.

Except the pyramids have already been built.

So we'll never know what technology the pyramid builders used.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Scott Mayers » Sun Apr 21, 2019 1:24 am

I think that the OP begun well but now needs to step back to express the historical route of discovery of expansion. What many don't make sense of is how even any apparent evidence of expansion should be determined as proof of expansion when we can't literally recreate this phenomena locally. This is reasonable to presume as a principle: if it appears unusually weird, then why accept an explanation that embraces the weirdness rather than hold off until one is more 'fitting' to our local capacity to experience things.

It is similar to watching some magician perform some show. Only it is worse when you are not permitted to rerun the show to analyze how the apparent magic occurred. Any apparent 'fit' explanation that preserves the appearance as a reality where the explanation itself is also unable to be demonstrated uniquely, makes any such explanation seem just a convenient construct to 'rationalize' something when some would prefer us to wait for a rationale that conserves the local interpretation.

This was a similar argument for why Einstein resisted the Copenhagen interpretation. Why presume that Nature throws out probabilities as real things when it would be best to only assert the confusion but wait. If we find some means to mathematically predict something through probabilities, this is justified but we should not extend this to mean that nature itself is indeterminate with respect to itself.

I propose a reconstruction here first of the collective evidence and explanations that historically lead to the interpretation of expansion.

One idea is to begin with how we first determine light intensity formulations and geometric means to measure distance using perspective analysis.

(1) How do you identify what occurs to the appearance of light at greater distances?

(2) How do you use geometry/trigonometry to determine the first standard distances.

These two questions are just a start of course. But some things, like Obler's paradox might add value to the thinking prior to this as well.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Atla » Sun Apr 21, 2019 2:36 am

Scott Mayers wrote:
Sun Apr 21, 2019 1:24 am
I think that the OP begun well but now needs to step back to express the historical route of discovery of expansion. What many don't make sense of is how even any apparent evidence of expansion should be determined as proof of expansion when we can't literally recreate this phenomena locally. This is reasonable to presume as a principle: if it appears unusually weird, then why accept an explanation that embraces the weirdness rather than hold off until one is more 'fitting' to our local capacity to experience things.

It is similar to watching some magician perform some show. Only it is worse when you are not permitted to rerun the show to analyze how the apparent magic occurred. Any apparent 'fit' explanation that preserves the appearance as a reality where the explanation itself is also unable to be demonstrated uniquely, makes any such explanation seem just a convenient construct to 'rationalize' something when some would prefer us to wait for a rationale that conserves the local interpretation.

This was a similar argument for why Einstein resisted the Copenhagen interpretation. Why presume that Nature throws out probabilities as real things when it would be best to only assert the confusion but wait. If we find some means to mathematically predict something through probabilities, this is justified but we should not extend this to mean that nature itself is indeterminate with respect to itself.

I propose a reconstruction here first of the collective evidence and explanations that historically lead to the interpretation of expansion.

One idea is to begin with how we first determine light intensity formulations and geometric means to measure distance using perspective analysis.

(1) How do you identify what occurs to the appearance of light at greater distances?

(2) How do you use geometry/trigonometry to determine the first standard distances.

These two questions are just a start of course. But some things, like Obler's paradox might add value to the thinking prior to this as well.
If you are looking for a logical picture despite appearances, then besides throwing out the "expanding universe starting with a Big Bang" idea, you must also throw out the "Steady State with matter/energy being created" idea. Only a "static and finite" universe is logical.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Scott Mayers » Sun Apr 21, 2019 3:06 am

@Atla,

You need to first find out how or why the concept of expansion was inferred, whether correct or not. But yes, the 'static' interpretation has to also at least be considered prior to expansion as a default assumption. So you can be wise to hold onto that assumption until proven otherwise. This is the intent of the thread though, right?

I already suggested it, but have you heard of the older "Obler's paradox" to start with?
Wikipedia into on Obler's paradox wrote: In astrophysics and physical cosmology, Olbers' paradox, named after the German astronomer Heinrich Wilhelm Olbers (1758–1840), also known as the "dark night sky paradox", is the argument that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. The darkness of the night sky is one of the pieces of evidence for a dynamic universe, such as the Big Bang model. In the hypothetical case that the universe is static, homogeneous at a large scale, and populated by an infinite number of stars, then any line of sight from Earth must end at the (very bright) surface of a star and hence the night sky should be completely illuminated and very bright. This contradicts the observed darkness and non-uniformity of the night.[1]

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Atla » Sun Apr 21, 2019 3:26 am

Scott Mayers wrote:
Sun Apr 21, 2019 3:06 am
You need to first find out how or why the concept of expansion was inferred, whether correct or not. But yes, the 'static' interpretation has to also at least be considered prior to expansion as a default assumption. So you can be wise to hold onto that assumption until proven otherwise. This is the intent of the thread though, right?
By "static" I mean unchanging. Perhaps I should write unchanging.
The logical picture is that we live in a part of the universe that appears to come from a Big Bang and appears to expand, but is fundamentally unchanging (all change is an illusion in the sense that spacetime is illusory in QM, but our observable universe was indeed packed into a Big Bang singularity at one point).
I already suggested it, but have you heard of the older "Obler's paradox" to start with?
That's a good argument against an infinite universe idea. So the logical picture is that the universe is unchanging and finite.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Scott Mayers » Sun Apr 21, 2019 3:36 am

Atla wrote:
Sun Apr 21, 2019 3:26 am
Scott Mayers wrote:
Sun Apr 21, 2019 3:06 am
You need to first find out how or why the concept of expansion was inferred, whether correct or not. But yes, the 'static' interpretation has to also at least be considered prior to expansion as a default assumption. So you can be wise to hold onto that assumption until proven otherwise. This is the intent of the thread though, right?
By "static" I mean unchanging. Perhaps I should write unchanging.
The logical picture is that we live in a part of the universe that appears to come from a Big Bang and appears to expand, but is fundamentally unchanging (all change is an illusion in the sense that spacetime is illusory in QM, but our observable universe was indeed packed into a Big Bang singularity at one point).
I already suggested it, but have you heard of the older "Obler's paradox" to start with?
That's a good argument against an infinite universe idea. So the logical picture is that the universe is unchanging and finite.
Read the link completely before you respond. It explains that the paradox was used from a static (non-dynamic) interpretation. The Big Bang IS an expanding space theory as is the Steady State as well. And, for precisely the identical position you take with Age, you appear to think identically. You cannot hold the Big Bang interpretation AND a Static one simultaneously. If anything begins all of matter compressed into a point in space, the space can only come about by what is defined as "expansion". The difference between the Steady State versus Big Bang interpretation is about whether the apparent 'singularity' is indicative of a literal origin or one of an infinite past but with an appearance (illusion) of an origin. But they both agree to space as expanding.

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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Atla » Sun Apr 21, 2019 5:09 am

Scott Mayers wrote:
Sun Apr 21, 2019 3:36 am
Atla wrote:
Sun Apr 21, 2019 3:26 am
Scott Mayers wrote:
Sun Apr 21, 2019 3:06 am
You need to first find out how or why the concept of expansion was inferred, whether correct or not. But yes, the 'static' interpretation has to also at least be considered prior to expansion as a default assumption. So you can be wise to hold onto that assumption until proven otherwise. This is the intent of the thread though, right?
By "static" I mean unchanging. Perhaps I should write unchanging.
The logical picture is that we live in a part of the universe that appears to come from a Big Bang and appears to expand, but is fundamentally unchanging (all change is an illusion in the sense that spacetime is illusory in QM, but our observable universe was indeed packed into a Big Bang singularity at one point).
I already suggested it, but have you heard of the older "Obler's paradox" to start with?
That's a good argument against an infinite universe idea. So the logical picture is that the universe is unchanging and finite.
Read the link completely before you respond. It explains that the paradox was used from a static (non-dynamic) interpretation. The Big Bang IS an expanding space theory as is the Steady State as well. And, for precisely the identical position you take with Age, you appear to think identically. You cannot hold the Big Bang interpretation AND a Static one simultaneously. If anything begins all of matter compressed into a point in space, the space can only come about by what is defined as "expansion". The difference between the Steady State versus Big Bang interpretation is about whether the apparent 'singularity' is indicative of a literal origin or one of an infinite past but with an appearance (illusion) of an origin. But they both agree to space as expanding.
Only in the Einsteinian (and the "everyday") sense can we talk about space and time, change and expansion, but more fundamentally spacetime is illusory, that's why some quantum effects ignore it. Not only is a literally changing universe logically impossible, it seems to have been refuted experimentally as well.

Yes, in the Einsteinian sense, the observable universe is "expanding", the observable universe comes from a Big Bang. You have to throw out the nonsensical ideas of infinite past and a literal origin, and ask yourself how the totality of the universe could be finite and unchanging anyway. So:
You cannot hold the Big Bang interpretation AND a Static one simultaneously.
So you could say that my interpretation is static/unchanging in the general/quantum sense and dynamic in the Einsteinan sense, and includes the Big Bang. It's the only tenable view as far as I'm concerned.

Atla
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Atla » Sun Apr 21, 2019 6:06 am

Scott Mayers wrote:
Sun Apr 21, 2019 3:36 am
You cannot hold the Big Bang interpretation AND a Static one simultaneously.
The easy part is explaining away expansion: if the observable universe is expanding then other part(s) of the universe must be contracting or "time" flows backwards there or whatever. And our observable universe will end in a Big Rip so the expansion here will reverse eventually (there's nothing strange about this since the rate of expansion already changed at least 3 times, so it will probably change again).

The difficult part is understanding that all our conception of time are linear, but time may be a closed loop so the distant future and the distant past are the same moment in time (same spacetime event).

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