Age of Universe: Dist. to Big Bang vs New Star

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Discussion Overview

The discussion revolves around the relationship between the distance to newly discovered stars and the age of the Universe, particularly in the context of the Big Bang. Participants explore the implications of astronomical distances and the nature of the Universe's expansion.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question why distances to new stars, such as one 15 billion light years away, are immediately associated with the age of the Universe, suggesting a model where the Universe is like a balloon, with distances on its surface potentially exceeding the distance to the Big Bang point.
  • One participant proposes a hypothetical scenario where if the Big Bang were around 20 billion years old, the distance to the Big Bang could be greater than that of a 15 billion year old star, raising questions about the implications of such a model.
  • Another participant corrects a previous post, clarifying that the star in question is actually 15 billion years old, not 15 years old.
  • One participant asserts that the Universe is approximately 13.2 billion years old, indicating that no star can be older than this age.
  • A later reply emphasizes that there is no specific "distance to the Big Bang point," explaining that the Big Bang occurred simultaneously at all points in the Universe and discussing the implications of light travel time on our observations of distant objects.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between distance, age, and the nature of the Big Bang, with no consensus reached on these concepts.

Contextual Notes

There are limitations in the assumptions made regarding the age of stars and the interpretation of distances in relation to the Big Bang, as well as the implications of the Universe's expansion on these distances.

Gonçalo
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Question

When astronomers find a new star, say 15 billion light years away, why do they immediately relate that distance with the age of the Universe (the distance to the Big Bang point)?

--->cause if the Universe were like a balloon, and the Earth and the star were in the the surface of that ballon, their distance could be much bigger than the distance of the Earth to the Big Bang point!...
 
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Originally posted by Gonçalo
Question

When astronomers find a new star, say 15 billion light years away, why do they immediately relate that distance with the age of the Universe (the distance to the Big Bang point)?

--->cause if the Universe were like a balloon, and the Earth and the star were in the the surface of that ballon, their distance could be much bigger than the distance of the Earth to the Big Bang point!...
if the big bang were let's say around 20 billion years (im considering a time frame which is longer than the star's life span) (which is not but for the sake of the argument it is) old then the distance between the Earth and the big bang would be bigger than the 15 year old star.
 


Originally posted by loop quantum gravity
if the big bang were let's say around 20 billion years (im considering a time frame which is longer than the star's life span) (which is not but for the sake of the argument it is) old then the distance between the Earth and the big bang would be bigger than the 15 year old star.

If the 15 year old star was, oh, let's say markoolio, would that make any difference?

Will he burn stronger than any other star?
 
sorry it's should be 15 billion year old star.
 
Actually the whole universe is only about 13.2 billion years old so no star is that old.
 
There is no distance in space "to the Big Bang point". The Big Bang occurred simultaneously at every point in the universe. It was not an explosion of stuff into the void, it was (in part) the creation & rapid expansion of space itself.

When astronomers see a distant object (e.g., billions of light years away) they relate it to the age of the universe (currently calculated to be 13.7 billion years plus or minus a bit) because the speed of light is finite, and as such, the further away we look, the older the image we see. Since the Big Bang occurred 13.7 billion years ago, we cannot see anything further than 13.7 billion light years away because light from parts of the universe more distant than that has not reached us yet.

And since the Big Bang was the beginning of the entire universe, nothing in the universe can be older than that. (at least, the "visible universe"..i.e., the stuff within our 13.7 billion mile viewing range)

For more info, post questions to the regular forum...
https://www.physicsforums.com/forumdisplay.php?s=&daysprune=&forumid=71
 

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