Unit transformation of Cosmological Constant ?

AI Thread Summary
The discussion revolves around the unit transformation of the cosmological constant, specifically converting between GeV and eV, as well as comparing energy densities in different units. Participants emphasize the importance of understanding the dimensional relationships between energy, mass, and time in cosmology, noting that eV represents energy while energy densities can be expressed in terms of energy to the fourth power. The conversation also highlights the relevance of these conversions in cosmological equations, particularly in scalar field inflation models. Additionally, a challenge related to the fine-tuning problem and dark energy is mentioned, indicating ongoing exploration in the field. Overall, the thread serves as a resource for those looking to grasp unit conversions in cosmology.
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Question : How to unit transformation of Cosmological Constant?

10-47 GeV4 ===> ? eV
or, x eV ===> ? GeV4


1) How compair ( X ) GeV4 with ( Y ) eV ?

2) How compair ( 10-29 g/cm3) with (Y eV)?

please, easely explain to me!
and, have a nice day!
 
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Try these conversions. They are a good tool when working with cosmology equations like scalar field inflation models.

Temperature: 1 GeV ---> 10^13 K
Mass: 1 GeV ---> 10^-25 g
Time: 1 GeV^-1 ---> 10^-24 sec
Length: 1 GeV^-1 ---> 10^-14 cm
 
Thanks you!
I will try by them.

If reader have a better idea, please write down!
 
You are comparing energies with energydensities. eV is of dimension energy.
But if c=hbar=1 (cosmologists tend to redefine their units like that), length and time have the same dimension, that is they are both of dimension energy^-1.

Thus, energy densities (energy/Length^3) have the same dimension as energy^4.
 
Thanks Amanheis! good explain!

I have make a challenge to that fine tuning problem(the reason of that mass density of universe close to critical mass density), inflation mechanism(start and end), the reason of that dark energy has a small value, future of our universe, at Physics Forums Blog.
 
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edgepflow said:
Try these conversions. They are a good tool when working with cosmology equations like scalar field inflation models.

Temperature: 1 GeV ---> 10^13 K
Mass: 1 GeV ---> 10^-25 g
Time: 1 GeV^-1 ---> 10^-24 sec
Length: 1 GeV^-1 ---> 10^-14 cm

I got a solution
 
Last edited:

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