The Reissner-Nordstrom metric

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The discussion focuses on the Reissner-Nordstrom metric in relation to spinless charged neutron stars, highlighting differences in equations from two references regarding electric system charge. Reference 2's equation incorporates two metric components, while reference 3 uses only one, raising questions about the dimensionality and implications of these components. The equations suggest that charge contributes to mass through a relationship involving the radial distance and electric field, with a derived formula for the electric field based on the charge distribution. Additionally, the four-current and its role in the covariant Maxwell field equation are discussed, emphasizing the significance of the metric components in the context of electromagnetic sources. The conversation aims to clarify these complex relationships and their implications in general relativity.
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Two citations referenced by Wikipedia with respect to General Relativity models for spinless charged neutron stars, reference 2 - eq. 24, states that the Reissner-Nordstrom metric relativistic Einstein-Maxwell Gauss law for the electric system charge is:
Q(r) = \int_0^r 4 \pi j^0 e^{\frac{(\nu + \lambda)}{2}} dr

However, according to reference 3 - eq. 5, the electric system charge is:
Q(r) = \frac{1}{r^2} \int_0^r 4 \pi r^2 \rho_{ch} e^{\frac{\lambda}{2}} dr

What Einstein-Maxwell charge effects with respect to the metric components \nu and \lambda are these equations describing?

Why does the reference 2 equation have two metric components and the reference 3 equation has only one metric component?

Why is the reference 2 equation missing the r^2 dimensions?

And what are the International System of Units (S.I.) for j^0 and \rho_{ch}?

Please post links to this thread for subject equations cross-reference.
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Reference:
http://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric"
http://arxiv.org/PS_cache/arxiv/pdf/0705/0705.2708v2.pdf"
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332004000200038"
 
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total mass of charged neutron star...


How was this equation generated?

Total mass of spinless charged neutron star at a radial distance r:
\frac{dm(r)}{dr} = \frac{4 \pi r^2 \epsilon(r)}{c^2} + \frac{Q(r)}{c^2 r} \frac{dQ(r)}{dr}

How exactly does charge contribute to mass this way?
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Reference:
http://arxiv.org/PS_cache/arxiv/pdf/0705/0705.2708v2.pdf"
 
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Please post links to this thread for subject equations cross-reference.
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nu metric component...



Given that F^{\mu \kappa} satifies the covariant Maxwell field equation:
\left[\sqrt{-g} F^{\kappa \mu} \right]_{, \mu} = 4 \pi J^{\kappa} \sqrt{-g}

The quantity J^{\kappa} denotes the four-current which represents the electromagnetic sources in the star. For a static spherically symmetric system, the only non-zero component of the four-current is J^1, which implies that the only non-vanishing component of F^{\kappa \mu} is F^{01}:

In this case I derived this formula for the relativistic electric field:
F^{01}(r) = E(r) = \frac{Q(r)}{r^2} e^{- \frac{ \left( \nu + \lambda \right)}{2}}

The formula suggested by the remaining reference papers:
F^{01}(r) = E(r) = \frac{Q(r)}{r^2}

Electric system charge:
Q(r) = \int_0^r 4 \pi j^0 e^{\frac{ \left( \nu + \lambda \right)}{2}} dr

The formula suggested by the remaining reference papers:
Q(r) = \int_0^r 4 \pi r^2 \rho_{ch} e^{\frac{\lambda}{2}} dr

Therefore:
\boxed{j^0 = \rho_{ch} r^2}

Integration by substitution:
F^{01}(r) = E(r) = \frac{e^{- \frac{ \left( \nu + \lambda \right)}{2}}}{r^2} \int_0^r 4 \pi j^0 e^{\frac{ \left( \nu + \lambda \right)}{2}} dr

Why does this solution have a \nu metric component and two metric components relativistic electric_field modifier e^{- \frac{ \left( \nu + \lambda \right)}{2}}?
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Reference:
http://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric"
http://arxiv.org/PS_cache/arxiv/pdf/0705/0705.2708v2.pdf"
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332004000200038"
http://www.google.com/url?sa=t&sour...o.pdf&usg=AFQjCNG7gtMPDuwpTrqYwoZ2NuS1lk1nRw"
 
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