Is a larger initial size for the universe possible?

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Discussion Overview

The discussion revolves around the possibility of the universe expanding from a significantly larger initial size, such as 10^25 meters, rather than the traditionally accepted 10^-35 meters. Participants explore implications for cosmological models, including the horizon problem, dark energy density, and nucleosynthesis of elements. The conversation also touches on metaphysical considerations regarding the universe's beginning and the nature of scientific inquiry.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Meta-discussion

Main Points Raised

  • Some participants question whether a larger initial size for the universe could resolve the horizon problem and explain the similarity between dark energy density and baryonic matter density.
  • Others propose the idea of infinitely many different Planck-like constants, suggesting potential connections between universes with different constants.
  • There are assertions that the question of the universe's beginning may be metaphysical and whether it belongs in a scientific forum.
  • Some participants express that many theorists believe the universe has always been infinite in size.
  • One participant suggests that dark energy may hold the key to understanding the universe's size and age, indicating that resolving dark energy issues could lead to answers for longstanding questions.
  • Concerns are raised about the adequacy of current mathematical descriptions in cosmology and their implications for understanding the universe.
  • There is speculation that universes with different Planck constants may not interact due to differing energy levels of atoms.

Areas of Agreement / Disagreement

Participants express a range of views, with no clear consensus on the implications of a larger initial universe size or the metaphysical nature of the universe's beginning. Multiple competing perspectives remain, particularly regarding the relationship between different universes and the role of dark energy.

Contextual Notes

Some discussions highlight limitations in current cosmological models and the potential for unresolved mathematical steps. The conversation also reflects varying interpretations of what constitutes a scientific question versus a metaphysical one.

Who May Find This Useful

This discussion may be of interest to those exploring cosmology, the philosophy of science, and the implications of theoretical physics on our understanding of the universe.

kurious
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Is it possible for the universe to expand from a very large initial size such as 10^25 metres instead of from the usual 10^-35 metres.
Could the universe have a high enough temperature at 10^25 metres?
Would nucleosynthesis of the elements give the right abundances?
My motivation for asking this is as follows:

(1) Wouldn't a large initial radius for the universe overcome the horizon problem?

(2)A large initial radius would explain why the dark energy density and
the baryonic matter density are so similar today.

These are not unreasonable questions given that there is so little evidence for the theory of inflation.
 
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I think it is a very interesting question in the case that there can be infinitely many different Plank-like constants, where each constant is the initial unit of another universe.

In this case we can ask if there can be any connection between two universes, which are based on different Plank-like constants.
 
Last edited:
with metaphysical questions kurious?

Is it not a metaphysical question to suppose the universe had a beginning?
Should we ask that question in a scientific forum?
Is it not that question part of the reason why our prevailing paradigm is askew?

Regards

EP
kurious said:
Is it possible for the universe to expand from a very large initial size such as 10^25 metres instead of from the usual 10^-35 metres.
Could the universe have a high enough temperature at 10^25 metres?
Would nucleosynthesis of the elements give the right abundances?
My motivation for asking this is as follows:

(1) Wouldn't a large initial radius for the universe overcome the horizon problem?

(2)A large initial radius would explain why the dark energy density and
the baryonic matter density are so similar today.

These are not unreasonable questions given that there is so little evidence for the theory of inflation.
 
You would probably find a fair percentage of theorists believe the universe has always been infinite in size.
 
Would an infinite Creator create a finite universe?

Regards

EP
Chronos said:
You would probably find a fair percentage of theorists believe the universe has always been infinite in size.
 
Epsilon Pi said:
Is it not a metaphysical question to suppose the universe had a beginning?
Should we ask that question in a scientific forum?
Is it not that question part of the reason why our prevailing paradigm is askew?

If its a metaphysical question or not doesn’t really matter. If you haven’t noticed these are the question physicists deal with everyday.

Unless you agree with the Popes advice given to physicists in a conference in 1981 that we should not inquire into the big bang itself because that was the moment of creation and thus the work of god.
 
It is only a metaphysical question like every other question until experimental evidence is found for it.I think dark energy holds the key to how big,small old and young the universe gets.If the issue of dark energy is resolved in the next few years we will be
privileged to be living at a time when some of the questions that people have asked
for thousands of years are answered.
 
Hi kurious,

Please look at post #2.
 
Paraphrasing Chronos I would say:

You would probably find a fair percentage of theorists and physicists are working with metaphysical questions, as they gave up given a mathematical description of their theories.

Regards

EP
Vast said:
If its a metaphysical question or not doesn’t really matter. If you haven’t noticed these are the question physicists deal with everyday.

Unless you agree with the Popes advice given to physicists in a conference in 1981 that we should not inquire into the big bang itself because that was the moment of creation and thus the work of god.
 
  • #10
Epsilon Pi said:
as they gave up given a mathematical description of their theories.

All their theories are based on mathematics, it's philosophers who need mathematical experience to understand these theories…
 
  • #11
Lama:
I think it is a very interesting question in the case that there can be infinitely many different Plank-like constants, where each constant is the initial unit of another universe.

In this case we can ask if there can be any connection between two universes, which are based on different Plank-like constants.

Kurious:
I would suspect that two universes with different Planck constants couldn't interact,
if each universe had the same particles in it.This is because the energy levels of atoms in each universe would be different and so phenomenoa such as absorption of photons from one universe by electrons in atoms of another would not occur.
Also, we would expect anisotropies in microwave background if other universes could contribute to our microwave background.However, a Planck constant that varies with time in our universe is a possibility, provided the other constants of nature vary too.
 
  • #12
Existence... then logic... then science?
 
  • #13
What about if their mathematical descriptions are askew, as is the prevailing paradigm? Their conclusions will be metaphysical in this stage of science; they do not agree in their cosmological point of view, as we have seen lately
What is a mathematical experience? I thought mathematics were a tool invented by human mind to interpret and describe, in the case of physicists, the physical world

Regards
EP
Vast said:
All their theories are based on mathematics, it's philosophers who need mathematical experience to understand these theories…
 
  • #14
kurious said:
I would suspect that two universes with different Planck constants couldn't interact.
I agree with you. In that case we can think about a universe which its initial plank-like constant is in the size of our universe.
 

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