Calculating Observable Universe Mass in the Lambda-CDM Model

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Discussion Overview

The discussion revolves around calculating the mass of the observable universe within the framework of the Lambda-CDM model, utilizing parameters from the Hubble Space Telescope and WMAP. Participants explore various equations and values related to baryon density, dark matter density, and critical mass, while questioning the implications of their findings.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant presents an equation for the observable universe mass based on Lambda-CDM parameters and calculates it to be approximately \(1.180 \times 10^{55} \, \text{kg}\).
  • Another participant corrects the baryon density stated in the first post, indicating it refers to stellar baryon density rather than total baryon density.
  • A subsequent post recalculates the observable universe mass using the corrected stellar baryon density, yielding a different value of approximately \(1.048 \times 10^{55} \, \text{kg}\).
  • Participants discuss the relationship between observable universe mass and Hubble critical mass, suggesting that the observable universe mass is greater than or equal to the Hubble critical mass.
  • One participant questions the cosmological implications of their findings regarding the mass criteria.
  • Another participant mentions the observable stellar baryon critical density and the observable cosmological critical density, providing additional context to the discussion.
  • Some participants express a need for peer review and proofreading of the equations before publication.

Areas of Agreement / Disagreement

There is no consensus on the correctness of the equations and calculations presented, as participants express uncertainty and seek peer review. Multiple competing views regarding the implications of the mass calculations remain unresolved.

Contextual Notes

Participants note that the calculations depend on specific definitions of baryon density and critical mass, and there are unresolved questions about the implications of the results within cosmological theories.

Orion1
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This is my equation for the Universe mass based upon the Lambda-CDM model parameters and the Hubble Space Telescope (HST) and WMAP observational parameters in SI units.

Observable Universe mass composition:
H_0 = 2.32987690448613 \cdot 10^{- 18} \; \text{s}^{- 1} - Hubble parameter (WMAP)
\Omega_b = 0.00444 - Baryon density
\Omega_{dm} = (\Omega_m - \Omega_b) = 0.2216 - dark matter density
dN_s = 10^{22} - HST observable stellar number
dV_s = 3.3871 \cdot 10^{78} \; \text{m}^3 \; \; \; (4 \cdot 10^{30} \; \text{ly}^3) - HST observable stellar volume
M_{\odot} = 1.9891 \cdot 10^{30} \; \text{kg} - solar mass

Observable Universe mass:
\boxed{M_u = \frac{4 \pi M_{\odot}}{3 \Omega_b} \left( \frac{dN_s}{dV_s} \right) \left( \frac{c}{H_0} \right)^3}

\boxed{M_u = 1.18029735794067 \cdot 10^{55} \; \text{kg}}

Gravitationally observable dark matter mass:
\boxed{M_{dm} = \frac{4 \pi M_{\odot}}{3} \left( \frac{\Omega_{dm}}{\Omega_b} \right) \left( \frac{dN_s}{dV_s} \right) \left( \frac{c}{H_0} \right)^3}

\boxed{M_{dm} = 2.61553894519654 \cdot 10^{54}}

Hubble critical mass:
\boxed{M_c = \frac{c^3}{2 G H_0}}
\boxed{M_c = 8.66352589042757 \cdot 10^{52} \; \text{kg}}
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Reference:
"[URL law - Wikipedia[/URL]
http://en.wikipedia.org/wiki/Lambda-CDM_model"
http://en.wikipedia.org/wiki/Universe"
http://en.wikipedia.org/wiki/Observable_universe"
http://en.wikipedia.org/wiki/Dark_matter"
 
Last edited by a moderator:
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Correction, the Baryon density listed in post #1 is the stellar Baryon density, not the total Baryon density.
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The stellar Baryon density ranges between:
\Omega_s = \int_{0.004}^{0.005}
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\Omega_s = 0.005 - stellar Baryon density

Observable Universe mass:
\boxed{M_u = \frac{4 \pi M_{\odot}}{3 \Omega_s} \left( \frac{dN_s}{dV_s} \right) \left( \frac{c}{H_0} \right)^3}

\boxed{M_u = 1.04810405385132 \cdot 10^{55} \; \text{kg}}

Gravitationally observable dark matter mass:
\boxed{M_{dm} = \frac{4 \pi M_{\odot}}{3} \left( \frac{\Omega_{dm}}{\Omega_s} \right) \left( \frac{dN_s}{dV_s} \right) \left( \frac{c}{H_0} \right)^3}

\boxed{M_{dm} = 2.32259858333452 \cdot 10^{54} \; \text{kg}}

Hubble critical mass:
\boxed{M_c = \frac{c^3}{2 G H_0}}

\boxed{M_c = 8.66352589042757 \cdot 10^{52} \; \text{kg}}
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Observable Universe mass greater than or equal to Hubble critical mass:
\boxed{M_u \geq M_c}

\boxed{\frac{4 \pi M_{\odot}}{3 \Omega_s} \left( \frac{dN_s}{dV_s} \right) \left( \frac{c}{H_0} \right)^3 \geq \frac{c^3}{2 G H_0}}

Observable Universe mass equivalent to Hubble critical mass:
\boxed{M_u = M_c}

\frac{4 \pi M_{\odot}}{3 \Omega_s} \left( \frac{dN_s}{dV_s} \right) \left( \frac{c}{H_0} \right)^3 = \frac{c^3}{2 G H_0}

Observable critical stellar Baryon density:
\boxed{\Omega_s = \frac{8 \pi G M_{\odot}}{3 H_0^2} \left( \frac{dN_s}{dV_s} \right)}

\boxed{\Omega_s = 0.604894627838177}

Total matter density:
\Omega_m = 0.266

According to my calculations, the observable Universe mass is greater than the Hubble critical mass.

What exactly are the cosmological theoretical implications for this criteria?
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Observable stellar Baryon critical density:
\Omega_s = 0.604894627838177

Observable cosmological critical density:
\Omega_{\Lambda} = 0.7
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Reference:
http://en.wikipedia.org/wiki/Lambda-CDM_model"
 
Last edited by a moderator:
Why don't you google 'Hubble critical mass' and publish 'your' results in an article?
 

malawi_glenn said:
Why don't you google 'Hubble critical mass' and publish 'your' results in an article?

All my equations require proofreading by a peer review, prior to any publication.

According to my calculations, the observable Universe mass is greater than the Hubble critical mass.

What exactly are the theoretical cosmological implications for this criteria?

Are my equations and calculations correct?
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Last edited:

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