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

Post by gaffo »

Age wrote: Sun Apr 21, 2019 11:26 am

So, if, say I was trillions and trillions and trillions of trillions of light years away from you on earth, and I shone my 9 volt torch in your direction, then it is a fact that you would see the light, because it spreads out and does NOT diminish, even if I am an idiot or not, correct?

nope -refer to earlier post on the matter.

negating the fact that if you were a trillion trillions of light years away in a universe 13.8 billion light years old, your beam of light is only .000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001 % closer to me than you are sitting on your planet with the flashlight.
gaffo
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo »

Age wrote: Sun Apr 21, 2019 11:33 am Atla.

The "olbers-paradox" from the explanation I just read, to me, says that the light from the more distant stars is dimmed because they are receding from the observer as the universe expands.
no. the light is dim because the stars are far away.

the light might ALSO be redshifted if those same stars are receding away from us.


Age wrote: Sun Apr 21, 2019 11:33 am Also, is light ONLY dimmed because of receding, or because of distance??
the latter, it would be redshifted if also receding.

in fact if some fast moving star decided to barrel toward us (When World colide) - it would be BRIGHT and BLUE on approach, and BRIGHT a RED on receding (bright becuase it would be close). a billion yrs later the same star would be dim (do to distance) - and still red due to still receding from us.

if that same star got plug back to us via a BH or something, then it would be a dim billion light year distant BLUE star - since it would be again moving toward us faster than the expansion of space between it and us.

BTW in the Local Group the biggest 3 galaxies are Andromeda, Milkyway, and Wilrpool. of them the first one is biggest by factor of 2 at least and very close. close enough that it is now moving to colide with us in 3.5 billion years. it will be pretty caotic when we colide, and will take a long time for a new larger "Super-galaxy" to re-from from the chaos. Whirlpool is near the edge of the Local Group and will just be an observer.
gaffo
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo »

Atla wrote: Mon Apr 22, 2019 8:47 am
Scott Mayers wrote: Mon Apr 22, 2019 8:33 am I'd be patient with Age still. It doesn't help to be riled up by it. Sometime it only makes it worse.
I think you underestimate the severity of psychotic delusions and the brutality needed to break through them.
The Steady State explanation assumes that the singularity is only an 'approach' rather than an actual zero point and that all matter is not actually crushed to a point there but that the apparent 14 Billion years is an illusion of parallel lines, like a railway track going off in the distance. The further away toward the apparent horizon point, we presume the wood ties are also placed parallel to each other but they appear to be bunching up towards that horizon.

Expansion can thus occur but would make the point on that horizon go further out. Imagine the ground of the imagined railway track stretching, something like how the 'horror movie' effect of a stretching hallway. The Steady State then presumes that if we were to go back 14 billion years, there would still be a Universe that appears 14 Billion years.
A problem is that then we have an infinite past, which is logically impossible (if we assume that the world makes logical sense, then this alone is enough to rule out Steady State).

Also, the observable universe seems to have been totally uniform about 13.8 billion years ago, so if we go back further, why was it uniform before that but not uniform after that?

---

Why don't you just assume that the Big Bang indeed happened, but it was not a beginning and only a part of our universe comes from this Big Bang, there must be other parts outside it?
becuase the theory of the BB is that "space, time, nor energy" existed prior to the BB.
gaffo
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo »

Age wrote: Mon Apr 22, 2019 9:22 am
WHERE is the actual "evidence" that the Universe is expanding?
Redshift via Edwin Hubble early 1920's.
gaffo
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo »

Atla wrote: Mon Apr 22, 2019 10:26 am
I predict that in somewhere between 10^14 and 10^40 years from now, once most of the stuff in our observable universe has fallen into black holes, the whole process will reverse and space will start to shrink again eventually leading to a Big Crunch, which is the same event as the Big Bang was.
nope, not enough mass, not even close. Universe is open and will just expand and cool until there is just a near infinate space with a few atoms floating around.

Atla wrote: Mon Apr 22, 2019 10:26 am Which brings up my biggest disagreement with modern science, they usually think that black holes have high entropy which is BULLSHIT.
??? BH have entropy?

the universe in the far future will, and all the BH will eventually "Evaporate" too (explode - then the energy/matter in them with expand and cool and become just more atoms floating in space.
gaffo
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by gaffo »

-1- wrote: Mon Apr 22, 2019 10:36 am guys. Space does not expand. Matter expands in space.
nope.

everything expands - space and matter.

-1- wrote: Mon Apr 22, 2019 10:36 am When it is said "the universe expands" they mean the MATTER in the KNOWN (OBSERVABLE) UNIVERSE.

nope, not sure where you got that idea.
-1- wrote: Mon Apr 22, 2019 10:36 am Keep this in mind, please.

Some corollaries follow:
1. The known universe is contained in a finite section of space.

yes
-1- wrote: Mon Apr 22, 2019 10:36 am 2. Space is infinitely large.
nope. space is finite, it was "smaller 13 billion yrs ago, its larger now, and will be larger still in the future - but finite.
-1- wrote: Mon Apr 22, 2019 10:36 am 3. We don't know what's happening in space outside the known universe.
we can reasonably assume its expanding at the same rate as space in the observable universe.

-1- wrote: Mon Apr 22, 2019 10:36 am 4. Matter seems to escape the KNOWABLE BOUNDARY (which is not a real boundary or a "magical" boundary; it is just our farthest distance we can see and look at) of our observed universe at the Event Horizon.
yes
-1- wrote: Mon Apr 22, 2019 10:36 am Enough of this bullshit that "space is expanding". It is not, and I personally guarantee it for you.
lol, if you say so. my bad. i have been corrected.
Age
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Age »

gaffo wrote: Thu Apr 25, 2019 5:00 am
Age wrote: Mon Apr 22, 2019 9:22 am
WHERE is the actual "evidence" that the Universe is expanding?
Redshift via Edwin Hubble early 1920's.
But if some stars/galaxies are blueshift, then how does that then conclude that the Universe, Itself, is expanding?

If galaxies are moving closer to us, as you just said andromeda is, then some could say that that, combined with the other blueshift galaxies/stars, is evidence that the Universe, Itself, is NOT expanding.

If redshift is evidence for an expanding Universe, then what is evidenced by blueshift?
Age
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Age »

gaffo wrote: Thu Apr 25, 2019 5:12 am
-1- wrote: Mon Apr 22, 2019 10:36 am guys. Space does not expand. Matter expands in space.
nope.

everything expands - space and matter.

-1- wrote: Mon Apr 22, 2019 10:36 am When it is said "the universe expands" they mean the MATTER in the KNOWN (OBSERVABLE) UNIVERSE.

nope, not sure where you got that idea.
-1- wrote: Mon Apr 22, 2019 10:36 am Keep this in mind, please.

Some corollaries follow:
1. The known universe is contained in a finite section of space.

yes
-1- wrote: Mon Apr 22, 2019 10:36 am 2. Space is infinitely large.
nope. space is finite, it was "smaller 13 billion yrs ago, its larger now, and will be larger still in the future - but finite.
-1- wrote: Mon Apr 22, 2019 10:36 am 3. We don't know what's happening in space outside the known universe.
we can reasonably assume its expanding at the same rate as space in the observable universe.

-1- wrote: Mon Apr 22, 2019 10:36 am 4. Matter seems to escape the KNOWABLE BOUNDARY (which is not a real boundary or a "magical" boundary; it is just our farthest distance we can see and look at) of our observed universe at the Event Horizon.
yes
-1- wrote: Mon Apr 22, 2019 10:36 am Enough of this bullshit that "space is expanding". It is not, and I personally guarantee it for you.
lol, if you say so. my bad. i have been corrected.
gaffo

You seem to speak as if you KNOW, for sure, what happened and what will happen.

How did you come to obtain this "knowledge"?

Can you inform me/us:

Did the Universe begin?

If so, when? How? And, from what exactly?
surreptitious57
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by surreptitious57 »

Local gravitational effects will not be immediately affected by the overall expansion of the Universe
And this is why some galaxies will be blue shifted - because in cosmic terms they are relatively close
This also applies to any bodies that are relatively close to each other such as moons / planets / stars
surreptitious57
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by surreptitious57 »

I wrote:
Space does not expand
Space is not a static medium but one capable of distortion in many forms due to the effects of general relativity
And dark energy is the mysterious force responsible for the expansion of space both within and without galaxies
Age
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Age »

Scott Mayers wrote: Wed Apr 24, 2019 12:36 pm @Age,

Sorry again for not answering quicker. I'm not online as much in the last few days but WILL try to respond to as much as I can as long as you are not in a hurry. You write a lot to respond to and I need time to get through them bit by bit.

I'll jump first to respond to the point of linking you to the "Cosmological Principle" earlier. [I actually agree to your point about redirecting to links. I felt it was sufficient and clear of one to explain matters I did not need to rewrite.] But...

The principle is an "assumption" of convention for science. Because science is only a group project, people have to agree to a minimal set of conditions before moving forward.
And one of those conditions, before moving forward, could be let us just LOOK AT 'that' what it IS that we have observed and seen, only, BEFORE we make any 'assumption' at all, always.
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pmThe principles are just conventions that require assuming first that what we live in the SAME world that we have to assume is consistent universally.
But "we" do NOT have to assume that at all.

In fact, if we DID assume that, then this may effect the way we LOOK AT 'that' what we have observed and seen. We may, after all, start "interpreting" 'that', what has actually been observed and seen, through a distorted vision, and then SEE things that are NOT really and actually the Truth of things.
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pmThis means that we need to separate subjective beliefs about reality, such as religious Cosmological origin stories from the activity of observing the skies.
1. WHY have ANY "BELIEF" to start with?
2. If there is NO "BELIEF" nor "ASSUMPTION", then there is nothing to separate, nor even a "need" to do any such thing.
3. WHY remove SOME "stories" but leave other ones behind?

The general Cosmological Principle is that we are not in any 'special' place such that the physics here is the same everywhere in this Universe. We ran into problems in previous times of believing that Earth was the center of the Universe and that the Universe itself was 'made' FOR us specifically.[/quote]

If people STILL believe or disbelieve either, then they will STILL continue to run into, what you call, "problems".
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pm So this is just a set of statements that say first and foremost that the universe is perceptibly the same no matter where you are in SPACE and that the distribution is assumed to be the same.
The distribution of 'what' EXACTLY is ASSUMED to be the same?
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pm The Steady State theorists felt this was not sufficient and opts to add that TIME as also something we have to add to make the principle of assumption more complete. We thus, cannot assume that in time NOR space that reality was different than our local capacity to understand things. If not, we could include the religious miracles believed about the past, for instance. If we place Adam and Eve as our literal first humans with some God that created us in a time where magic was 'normal', then this kind of thinking would defeat the universality of the study of science.
The study of the Universe has been and is continually being defeated by all of these BELIEFS (believing and NOT believing in and of things) that are currently being held, which are also being passed onto "others" to either BELIEVE or NOT BELIEVE.

ALL of the truths AND falsehoods within ALL of these "stories" about adam and eve, God, created human beings, steady states, static Universe, multiple universes, one beginning Universe, evolution, et cetera, et cetera CAN already bee SEEN and KNOWN, almost instantly. But this can NOT happen if one already BELIEVES or ASSUMES that they ALREADY KNOW what thee Truth IS.
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pmBecause evolution is understood as a 'fact', some think that the Big Bang CAN still possibly be determined to have a different past than it is now. This enables the Big Bang to be viable.
If I recall correctly it was you who stated the big bang means that it was the beginning. So, what do you mean by the big bang CAN still possibly be determined to have a different past than it is now? What "past" is it "now"?
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pm I personally think that this was a politically intentional convention because it still allows all science we study for most purposes to be valid regardless of any actual Cosmic origin 'stories'.
This is twice you have mentioned here in this post about studying 'science'.

Do human beings actually study science, or, do human beings actually study 'things', through a scientific process, which could be known as 'science'?

Is 'science' the systematic study of things, or do people study 'science'?
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pmSince science, as an institute involves the need to raise money and political supports, if you include the Perfect Cosmological Principle (that's what the Steady State Theory added of time), that there is little room for ANY religious origin story.
WHY?

It was, after all, religious origin stories, which has helped lead so many human beings to now still having the ASSUMPTION, and the BELIEF, that there was even a beginning to the Universe. LOOKING AT the Truth about WHERE the origin ASSUMPTION and BELIEF came from, then UNDERSTANDING WHY that ASSUMPTION and BELIEF still remains within some human beings helps to SHOW what the actual and real Truth IS.

Absolutely EVERY thing needs to be LOOKED AT and questioned IF the Truth is what people are LOOKING FOR.

"Making" room for some stories and NOT others does NOT help in discovering the actual Truth of things.
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pm This tends to piss people off and make them NOT want their personal, corporate, religious, or governments to fund the effort as well.
To SEE what the Truth IS does NOT take money. TRYING TO raise money, is just another attempt at "justification" for greed, just to fill one's own pockets is NOT needed at all.
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pm Belief still has a role in moral conventions and as long as it is deemed less important to worry about, such as what is or is not true about the Universe as a whole, then allowing for flexibility of science in these areas concerning historical facts about it should not be as big a concern. I disagree but think this may be why the Perfect Cosmological Principle and the Steady State theory is preferentially undesired by many.
The REASON WHY these things are NOT preferred or undesired IS because they do NOT fit in with the BIG picture, which is thee Truth of things.
Scott Mayers wrote: Wed Apr 24, 2019 12:36 pmSo, I'll leave on this point for now and get back to you later on the rest.
Age
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Age »

surreptitious57 wrote: Thu Apr 25, 2019 7:11 am Local gravitational effects will not be immediately affected by the overall expansion of the Universe
If there is an 'overall' expansion of the Universe, then WHY will "local" gravitational effects NOT be immediately affected?

The word 'overall' has a connotation of, literally, over ALL of the Universe.

Also, WHEN WILL the so called "local" gravitational effect start to be affected? And, WHY do only "local" gravitational effects take longer to be "affected".

To me this seems just like another attempt to TRY TO "justify" why there is an apparent difference between what apparently is happening "locally" and further out.
surreptitious57 wrote: Thu Apr 25, 2019 7:11 amAnd this is why some galaxies will be blue shifted - because in cosmic terms they are relatively close
But "closeness" or not has NO bearing on blue nor red shifted. Or, that is what is told in a book referenced in the thread titled 'einstein on the train'.

And, it was those 'facts' in that book that confirmed my previous observations and further supported my VIEW regarding this issue. Those 'facts' also alighted me to what is actually happening, and thus further to HOW the Universe is NOT expanding.
surreptitious57 wrote: Thu Apr 25, 2019 7:11 amThis also applies to any bodies that are relatively close to each other such as moons / planets / stars
So, are you saying that moons, planets, and stars no matter where they are in the Universe are contracting together depending on if they are close to each other?

If that is what you are saying, then could you explain how this is possible in an expanding Universe?

If, however, that is not what you are saying, then can you clarify what you are saying?

What is 'relatively close' in relation to, actually?

Remembering that ' "local" gravitational effects' also applies to things like galaxies as well as solar systems, stars, planets, moons, and other objects.
Age
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Age »

surreptitious57 wrote: Thu Apr 25, 2019 7:21 am
I wrote:
Space does not expand
Space is not a static medium but one capable of distortion in many forms due to the effects of general relativity
It is amazing just how many times people will just COPY and REPEAT what another has said, only because it sounds "right" and 'fits in what they ALREADY ASSUME and/or BELIEVE is true, right, and/or correct. But if questioned and/or challenged enough they can NOT explain how it actually is true nor right.

What is 'space'?

And, if you say 'space' expands, then HOW can it?
surreptitious57 wrote: Thu Apr 25, 2019 7:21 amAnd dark energy is the mysterious force responsible for the expansion of space both within and without galaxies
So, a completely mysterious force (something like a God) is "responsible", for the expansion of space, (the Universe). Now, is this an irrefutable 'fact', or, Is it just some thing expressed to "explain" some thing NOT yet understood nor known?

Saying, "God is the mysterious force responsible for everything" is ALSO an expression to "explain" that what is NOT yet understood nor known.
Saying, "Dark energy is the mysterious force responsible for the Universe" is, to me, just as ridiculous a statement as the previous one is.

Even after countless of centuries of human beings making up words/labels to explain things that are unknown, and a community of human beings who call themselves "scientists" separating themselves away from another community of human beings who call themselves "religious" and the separation being made stronger through ridicule for using words like "God" to TRY TO "explain" the unknown, now this same group of so called "scientists" are making up and using words like "dark energy" to describe what it is that they, themselves, can NOT even begin to TRY TO "explain".

One faction of human beings ends up doing the EXACT SAME that another faction does, which the former faction used as an excuse for causing the faction in the first place.

WHEN are you human beings ever going to wake up to yourselves?

What IS the actual and real Truth to the questions:

1. Is there a beginning to the Universe, Itself?
2. WHERE did the ASSUMPTION/BELIEF that there is even a beginning come from?
3. Is the Universe infinite or finite?
4. Is the Universe eternal or not?
5. What could be a boundary/end point to a finite universe?
6. What could start/begin a Universe?
7. How could space expand?

If you do NOT yet KNOW the actual and real Truth to any or ALL of these, plus plenty of other, questions, then I suggest STOP ASSUMING and/or BELIEVING that you do KNOW the answers. The only ones you are FOOLING are your SELF's.

IF you can answer some but NOT ALL of these questions, but you can NOT fit them ALL into One sound and valid OBVIOUSLY CRYSTAL CLEAR picture, then I suggest that JUST MAYBE the answer/s you have are NOT the real and true ANSWERS at all. They could well be the actual True and Right ANSWERS but you will NEVER know until you are LOOKING AT and SEEING the WHOLE and True BIG picture of things.
Logik
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by Logik »

Age wrote: Thu Apr 25, 2019 8:21 am The word 'overall' has a connotation of, literally, over ALL of the Universe.
Because variance

Overall, humans have become much taller in the last 500 years. But some are still 1.5 meters tall.
surreptitious57
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Re: The Expanding Universe -- Why and How We Know It Is Expanding

Post by surreptitious57 »

Age wrote:
What IS the actual and real Truth to the questions:

I. Is there a beginning to the Universe Itself ?
2. WHERE did the ASSUMPTION / BELIEF that there is even a beginning come from ?
3. Is the Universe infinite or finite ?
4. Is the Universe eternal or not ?
5. What could be a boundary / end point to a finite universe ?
6. What could start / begin a Universe ?
7. How could space expand ?

If you do NOT yet KNOW the actual and real Truth to any or ALL of these plus plenty of other questions then I suggest STOP
ASSUMING and / or BELIEVING that you do KNOW the answers. The only ones you are FOOLING are your SELF

IF you can answer some but NOT ALL of these questions but you can NOT fit them ALL into One sound and valid OBVIOUSLY
CRYSTAL CLEAR picture then I suggest that JUST MAYBE the answers you have are NOT the real and true ANSWERS at all
They could well be the actual True and Right ANSWERS but you will NEVER know until you are LOOKING AT and SEEING
the WHOLE and True BIG picture of things
I - I dont know if there is a beginning to the Universe
2 - The belief that the Universe had a beginning came from religion
3 - I dont know if the Universe is infinite or finite
4 - I dont know if the Universe is eternal or not eternal
5 - I dont know what a boundary / end point would look like
6 - A Big Bang or quantum expansion could start a Universe
7 - Space could expand through inflation or dark energy or repulsive gravity

As you can see I have only managed to answer three of those questions and one of them was number 2
Which doesnt really belong there as its not actually a scientific question - unlike the others which are

The two questions I answered were more speculative than definitive
Which is say there is probably not a single absolute answer to them

So that leaves two answers out of a possible six so there is not much assuming going on here
Four of those questions I have not made any assumptions about at all as you can clearly see
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