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the big bang has been studied by a number of people and found
not to contain a singularity
(the density does not go infinite but has a finite limit)
a good recent paper is
http://arxiv.org/gr-qc/0407074
Genericity of the Big Bounce in isotropic loop quantum cosmology'
Date and Hossain
they calculate, among other things, the maximum energy density that occurred right at the crossover between contraction and the onset of expansion
you can guess
the energy density at the onset of expansion is bounded (Date and Hossain argue) by our old friend the Planck energy density!
So we can say, in joules per cubic meter, what is the mother of all energy densities.
or if you prefer in kilograms per cubic meter---with the understanding that it is kilograms of mass-energy---using mass to measure equivalent energy content
We can figure it out----the Planck energy unit is 2 GJ------2E9 joules
and the Planck unit volume is 4.2E-105 cubic meter
So just divide and it comes out around
4.6E113 joules per cubic meter.
divide by c2 if you want kilograms per cubic meter
i guess that means divide be 9E16
planck unit energy density may seem useless because so huge
but it is actually an OK unit and its nice to know that it was back there
at the bounce and so-to-say participated in bringing us into being
and there it is: 4.6 x 10113 joules per cubic meter
not to contain a singularity
(the density does not go infinite but has a finite limit)
a good recent paper is
http://arxiv.org/gr-qc/0407074
Genericity of the Big Bounce in isotropic loop quantum cosmology'
Date and Hossain
they calculate, among other things, the maximum energy density that occurred right at the crossover between contraction and the onset of expansion
you can guess
the energy density at the onset of expansion is bounded (Date and Hossain argue) by our old friend the Planck energy density!
So we can say, in joules per cubic meter, what is the mother of all energy densities.
or if you prefer in kilograms per cubic meter---with the understanding that it is kilograms of mass-energy---using mass to measure equivalent energy content
We can figure it out----the Planck energy unit is 2 GJ------2E9 joules
and the Planck unit volume is 4.2E-105 cubic meter
So just divide and it comes out around
4.6E113 joules per cubic meter.
divide by c2 if you want kilograms per cubic meter
i guess that means divide be 9E16
planck unit energy density may seem useless because so huge
but it is actually an OK unit and its nice to know that it was back there
at the bounce and so-to-say participated in bringing us into being
and there it is: 4.6 x 10113 joules per cubic meter
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