What if the universe's expansion is actually slowing down?

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Discussion Overview

The discussion centers around the concept of the universe's expansion and whether it is actually slowing down, challenging the prevailing notion that it is accelerating. Participants explore implications for dark energy and dark matter, while engaging in a debate about cosmological interpretations and the understanding of redshift data.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant suggests that because we observe distant galaxies as they were in the past, their current velocities could be slower than what is inferred from redshift data, proposing that the universe's expansion might be slowing down.
  • Others challenge this viewpoint, asserting that professional cosmologists have already considered such ideas and that current models account for light travel time and other complexities in interpreting redshift measurements.
  • Some participants emphasize that the consensus among scientists is that the universe is indeed expanding at an accelerating rate, citing historical studies from the 1990s that reached this conclusion.
  • There are calls for the original poster to engage with established cosmological literature and to avoid personal speculation without grounding in mainstream scientific sources.

Areas of Agreement / Disagreement

Participants express disagreement, with some supporting the idea of a slowing expansion while the majority uphold the view that the universe is currently expanding at an accelerating rate. The discussion remains unresolved, with no consensus reached.

Contextual Notes

Participants note the importance of understanding complex cosmological concepts and the need for rigorous mathematical validation of claims. There are references to prior discussions on similar topics, indicating a history of debate on this issue.

Who May Find This Useful

This discussion may be of interest to individuals exploring cosmology, particularly those curious about the dynamics of the universe's expansion and the implications of redshift measurements.

Robert Hoffmann
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Hello guys,

every "scientist" I have talked to say the universe is "expanding" at an ever increasing rate.

then I tell them the following: "hey man, you say the farther away the galaxies you see, the quicker away from us they are moving, right ? (redshift, etc)"

they say: "yeah"

then I say: "but you're looking into the past, and the farther they (objects) are, the older the information we get (light) is...
so the way I see it, LONG TIME AGO they were moving faster, but not now... I think it's actually slowing down"

and then they just stare...

that simple issue will get rid of: dark energy, dark matter, senseless lunacy.

try it !
 
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Robert Hoffmann said:
Hello guys,

every "scientist" I have talked to say the universe is "expanding" at an ever increasing rate.

then I tell them the following: "hey man, you say the farther away the galaxies you see, the quicker away from us they are moving, right ? (redshift, etc)"

they say: "yeah"

then I say: "but you're looking into the past, and the farther they (objects) are, the older the information we get (light) is...
so the way I see it, LONG TIME AGO they were moving faster, but not now... I think it's actually slowing down"

and then they just stare...

that simple issue will get rid of: dark energy, dark matter, senseless lunacy.

try it !
Yes, I think senseless lunacy is a good description of your post. You should study some basic cosmology. Also, you idea has been shot down on this forum approximately 879 times so far. Try a forum search. A good place to start is the links at the bottom of this page.
 
Oh my gosh! None of us have ever thought of that before! Seriously, do you really think that professional cosmologists who have spent their careers working on this haven't thought of this obvious issue? Of course this is taken into account when interpreting measured data and modeling the expansion of the universe. If you are really interested in learning more about cosmology, I suggest getting an introductory book or doing some online study. Ned Wright's Cosmology Tutorial might be a good place to start.
 
The measurements of acceleration stem from the precise measurements of the redshifts and distances of large numbers of objects and large-scale structures in our universe, fully taking into account complicated things like light travel time. Yes, objects are moving away from one another at an accelerated rate today.
 
They stare at you not because they are stumped by your question, but flabbergasted by your rejection of an idea that you don't understand.

They also aren't guessing, everyone (and I mean everyone) thought the universe was slowing down. In the 90s, two different teams set out to find out how much it was slowing down. Both came to the same conclusion that it was accelerating, and both came up with the same rate. You can argue ideas until you are blue in the face, but unless you can find an error in their math or a mechanism they didn't think of, you can't argue the science. You could take their data and redo the calculations if you want.
 
Thread closed for Moderation...
 
Thread will remain closed. The new OP has been reminded of the PF rules against personal speculation, and the need to post links to mainstream souces when asking questions here. He's also been reminded that the "A" prefix is to be used when wanting replies at the PhD level. :smile:
 

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