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739 changes: 555 additions & 184 deletions (current)novel-fermi-function.tex

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60 changes: 60 additions & 0 deletions Old_version.tex
Original file line number Diff line number Diff line change
Expand Up @@ -557,6 +557,66 @@ \section{Results and Discussion}
% Cheng Tao - This novel form is numerically friendly as the finite temperature components are naturally exponentially suppresses while also preserving the sign of all corrections making the formulation easier to numerically integrate.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Magnetization Example}
\label{magnetization}
{\bf ??Move to separate document??}
\noindent As an application of the novel form of the Fermi distribution, we introduce the problem of relativistic charged/magnetic gasses in a nearly homogeneous and isotropic fields. This problem has applicability in the primordial universe when such gasses were dense and rapidly cooling.

The grand partition function for the relativistic Fermi-Dirac ensemble is given by the standard definition
\begin{alignat}{1}
\label{part:1} \ln\mathcal{Z}_\mathrm{total}=\sum_{\alpha}\ln\left(1+\Upsilon_{\alpha_{1}\ldots\alpha_{m}}\exp\left(-\frac{E_{\alpha}}{T}\right)\right)\,,\qquad\Upsilon_{\alpha_{1}\ldots\alpha_{m}}=\lambda_{\alpha_{1}}\lambda_{\alpha_{2}}\ldots\lambda_{\alpha_{m}}
\end{alignat}
where we are summing over the set all relevant quantum numbers $\alpha=(\alpha_{1},\alpha_{2},\ldots,\alpha_{m})$. We note here the generalized the fugacity $\Upsilon_{\alpha_{1}\ldots\alpha_{m}}$ allowing for any possible deformation caused by pressures $\lambda_{\alpha_{i}}$ effecting the distribution of any quantum numbers.

In the case of the Landau problem where the gas is made up of charged particles such as electrons and positrons, there is an additional summation over $\widetilde{w}$ which represents the occupancy of Landau states~\citep{greiner2012thermodynamics} which are matched to the available phase space within $\Delta p_{x}\Delta p_{y}$. If we consider the orbital Landau quantum number $n$ to represent the transverse momentum $p_{T}^{2}=p_{x}^{2}+p_{y}^{2}$ of the system, then the relationship that defines $\widetilde{w}$ is given by
\begin{alignat}{1}
\label{phase:1} \frac{L^{2}}{(2\pi)^{2}}\Delta p_{x}\Delta p_{y}=\frac{eBL^{2}}{2\pi}\Delta n\,,\qquad\widetilde{w}=\frac{eBL^{2}}{2\pi}\,.
\end{alignat}
The summation over the continuous $p_{z}$ is replaced with an integration and the double summation over $p_{x}$ and $p_{y}$ is replaced by a single sum over Landau orbits
\begin{alignat}{1}
\label{phase:2}
\sum_{p_{z}}\rightarrow\frac{L}{2\pi}\int^{+\infty}_{-\infty}dp_{z}\,,\qquad\sum_{p_{x}}\sum_{p_{y}}\rightarrow\frac{eBL^{2}}{2\pi}\sum_{n}\,,
\end{alignat}
where $L$ defines the boundary length of our considered volume $V=L^{3}$.

The partition function of the $e^{+}e^{-}$ plasma can be understood as the sum of four gaseous species
\begin{align}
\label{partition:0}
\ln\mathcal{Z}_{e^{+}e^{-}}=\ln\mathcal{Z}_{e^{+}}^{\uparrow}+\ln\mathcal{Z}_{e^{+}}^{\downarrow}+\ln\mathcal{Z}_{e^{-}}^{\uparrow}+\ln\mathcal{Z}_{e^{-}}^{\downarrow}\,,
\end{align}
of electrons and positrons of both polarizations $(\uparrow\downarrow)$. The change in phase space written in \req{phase:2} modify the magnetized $e^{+}e^{-}$ plasma partition function from \req{part:1} into
\begin{gather}
\label{partition:1}
\ln\mathcal{Z}_{e^{+}e^{-}}=\frac{e{B}V}{(2\pi)^{2}}\sum_{\sigma}^{\pm1}\sum_{s}^{\pm1}\sum_{n=0}^{\infty}\int_{-\infty}^{\infty}\mathrm{d}p_{z}\left[\ln\left(1+\lambda_{\sigma}\exp\left(-\frac{E_{\sigma,s}^{n}}{T}\right)\right)\right]\,\\
\label{partition:2}
\Upsilon_{\sigma,s} \rightarrow\lambda_{\sigma} = \exp{\frac{\mu_{\sigma}}{T}}\,,
\end{gather}
where the energy eigenvalues $E_{\sigma,s}^{n}$ are given by
\begin{align}
\label{cosmokgp}
E^{n}_{\sigma,s}(p_{z},{B})=\sqrt{m_{e}^{2}+p_{z}^{2}+e{B}\left(2n+1+\frac{g}{2}\sigma s\right)}\,,
\end{align}

% Notes to self: We need a density (chemical potential) value for neutron stars. This tells us the amount of positrons and neutrons.

% We want three quantities: The energy <E>, pressure <P>, and particle density <n>.

The index $\sigma$ in \req{partition:1} is a sum over electron and positron states while $s$ is a sum over polarizations. The index $s$ refers to the spin along the field axis: parallel $(\uparrow;\ s=+1)$ or anti-parallel $(\downarrow;\ s=-1)$ for both particle and antiparticle species.

We are explicitly interested in small asymmetries such as baryon excess over antibaryons, or one polarization over another. For matter $(e^{-};\ \sigma=+1)$ and antimatter $(e^{+};\ \sigma=-1)$ particles, a nonzero relativistic chemical potential $\mu_{\sigma}=\sigma\mu$ is caused by an imbalance of matter and antimatter. While the primordial electron-positron plasma era was overall charge neutral, there was a small asymmetry in the charged leptons (namely electrons) from baryon asymmetry~\citep{Fromerth:2012fe,Canetti:2012zc} in the universe. Reactions such as $e^{+}e^{-}\leftrightarrow\gamma\gamma$ constrains the chemical potential of electrons and positrons~\citep{Elze:1980er} as
\begin{align}
\label{cpotential}
\mu\equiv\mu_{e^{-}}=-\mu_{e^{+}}\,,\qquad
\lambda\equiv\lambda_{e^{-}}=\lambda_{e^{+}}^{-1}=\exp\frac{\mu}{T}\,,
\end{align}
where $\lambda$ is the chemical fugacity of the system.

We can then parameterize the chemical potential of the $e^{+}e^{-}$ plasma as a function of temperature $\mu\rightarrow\mu(T)$ via the charge neutrality of the universe which implies
\begin{align}
\label{chargeneutrality}
n_{p}=n_{e^{-}}-n_{e^{+}}=\frac{1}{V}\lambda\frac{\partial}{\partial\lambda}\ln\mathcal{Z}_{e^{+}e^{-}}\,.
\end{align}
In \req{chargeneutrality}, $n_{p}$ is the observed total number density of protons in all baryon species. The chemical potential defined in \req{cpotential} is obtained from the requirement that the positive charge of baryons (protons, $\alpha$ particles, light nuclei produced after BBN) is exactly and locally compensated by a tiny net excess of electrons over positrons.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Expand Down
66 changes: 65 additions & 1 deletion cuts.tex
Original file line number Diff line number Diff line change
Expand Up @@ -52,4 +52,68 @@
\frac{d}{dx}\sgn(x)&=2\delta(x)\,,\,\,\quad
\frac{d}{dE}\sgn(x)=\frac{2}{T}\delta(x)\,,
\end{align}
both without and with units and where $\delta(x)$ is the Dirac $\delta$-function. These cancel in \req{NFF1} at $x=0$ exactly as required since the derivative of the FD distribution written in \req{f_old} lacks a $\delta$-function. This encourages us to believe that all of singular expressions cancel leaving it fully analytic. This completes our demonstration of the validity of \req{NFF1}.
both without and with units and where $\delta(x)$ is the Dirac $\delta$-function. These cancel in \req{NFF1} at $x=0$ exactly as required since the derivative of the FD distribution written in \req{f_old} lacks a $\delta$-function. This encourages us to believe that all of singular expressions cancel leaving it fully analytic. This completes our demonstration of the validity of \req{NFF1}.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%Magnetization Example for future project
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Magnetization Example}
\label{magnetization}
{\bf ??Move to separate document??}
\noindent As an application of the novel form of the Fermi distribution, we introduce the problem of relativistic charged/magnetic gasses in a nearly homogeneous and isotropic fields. This problem has applicability in the primordial universe when such gasses were dense and rapidly cooling.

The grand partition function for the relativistic Fermi-Dirac ensemble is given by the standard definition
\begin{alignat}{1}
\label{part:1} \ln\mathcal{Z}_\mathrm{total}=\sum_{\alpha}\ln\left(1+\Upsilon_{\alpha_{1}\ldots\alpha_{m}}\exp\left(-\frac{E_{\alpha}}{T}\right)\right)\,,\qquad\Upsilon_{\alpha_{1}\ldots\alpha_{m}}=\lambda_{\alpha_{1}}\lambda_{\alpha_{2}}\ldots\lambda_{\alpha_{m}}
\end{alignat}
where we are summing over the set all relevant quantum numbers $\alpha=(\alpha_{1},\alpha_{2},\ldots,\alpha_{m})$. We note here the generalized the fugacity $\Upsilon_{\alpha_{1}\ldots\alpha_{m}}$ allowing for any possible deformation caused by pressures $\lambda_{\alpha_{i}}$ effecting the distribution of any quantum numbers.

In the case of the Landau problem where the gas is made up of charged particles such as electrons and positrons, there is an additional summation over $\widetilde{w}$ which represents the occupancy of Landau states~\citep{greiner2012thermodynamics} which are matched to the available phase space within $\Delta p_{x}\Delta p_{y}$. If we consider the orbital Landau quantum number $n$ to represent the transverse momentum $p_{T}^{2}=p_{x}^{2}+p_{y}^{2}$ of the system, then the relationship that defines $\widetilde{w}$ is given by
\begin{alignat}{1}
\label{phase:1} \frac{L^{2}}{(2\pi)^{2}}\Delta p_{x}\Delta p_{y}=\frac{eBL^{2}}{2\pi}\Delta n\,,\qquad\widetilde{w}=\frac{eBL^{2}}{2\pi}\,.
\end{alignat}
The summation over the continuous $p_{z}$ is replaced with an integration and the double summation over $p_{x}$ and $p_{y}$ is replaced by a single sum over Landau orbits
\begin{alignat}{1}
\label{phase:2}
\sum_{p_{z}}\rightarrow\frac{L}{2\pi}\int^{+\infty}_{-\infty}dp_{z}\,,\qquad\sum_{p_{x}}\sum_{p_{y}}\rightarrow\frac{eBL^{2}}{2\pi}\sum_{n}\,,
\end{alignat}
where $L$ defines the boundary length of our considered volume $V=L^{3}$.

The partition function of the $e^{+}e^{-}$ plasma can be understood as the sum of four gaseous species
\begin{align}
\label{partition:0}
\ln\mathcal{Z}_{e^{+}e^{-}}=\ln\mathcal{Z}_{e^{+}}^{\uparrow}+\ln\mathcal{Z}_{e^{+}}^{\downarrow}+\ln\mathcal{Z}_{e^{-}}^{\uparrow}+\ln\mathcal{Z}_{e^{-}}^{\downarrow}\,,
\end{align}
of electrons and positrons of both polarizations $(\uparrow\downarrow)$. The change in phase space written in \req{phase:2} modify the magnetized $e^{+}e^{-}$ plasma partition function from \req{part:1} into
\begin{gather}
\label{partition:1}
\ln\mathcal{Z}_{e^{+}e^{-}}=\frac{e{B}V}{(2\pi)^{2}}\sum_{\sigma}^{\pm1}\sum_{s}^{\pm1}\sum_{n=0}^{\infty}\int_{-\infty}^{\infty}\mathrm{d}p_{z}\left[\ln\left(1+\lambda_{\sigma}\exp\left(-\frac{E_{\sigma,s}^{n}}{T}\right)\right)\right]\,\\
\label{partition:2}
\Upsilon_{\sigma,s} \rightarrow\lambda_{\sigma} = \exp{\frac{\mu_{\sigma}}{T}}\,,
\end{gather}
where the energy eigenvalues $E_{\sigma,s}^{n}$ are given by
\begin{align}
\label{cosmokgp}
E^{n}_{\sigma,s}(p_{z},{B})=\sqrt{m_{e}^{2}+p_{z}^{2}+e{B}\left(2n+1+\frac{g}{2}\sigma s\right)}\,,
\end{align}

% Notes to self: We need a density (chemical potential) value for neutron stars. This tells us the amount of positrons and neutrons.

% We want three quantities: The energy <E>, pressure <P>, and particle density <n>.

The index $\sigma$ in \req{partition:1} is a sum over electron and positron states while $s$ is a sum over polarizations. The index $s$ refers to the spin along the field axis: parallel $(\uparrow;\ s=+1)$ or anti-parallel $(\downarrow;\ s=-1)$ for both particle and antiparticle species.

We are explicitly interested in small asymmetries such as baryon excess over antibaryons, or one polarization over another. For matter $(e^{-};\ \sigma=+1)$ and antimatter $(e^{+};\ \sigma=-1)$ particles, a nonzero relativistic chemical potential $\mu_{\sigma}=\sigma\mu$ is caused by an imbalance of matter and antimatter. While the primordial electron-positron plasma era was overall charge neutral, there was a small asymmetry in the charged leptons (namely electrons) from baryon asymmetry~\citep{Fromerth:2012fe,Canetti:2012zc} in the universe. Reactions such as $e^{+}e^{-}\leftrightarrow\gamma\gamma$ constrains the chemical potential of electrons and positrons~\citep{Elze:1980er} as
\begin{align}
\label{cpotential}
\mu\equiv\mu_{e^{-}}=-\mu_{e^{+}}\,,\qquad
\lambda\equiv\lambda_{e^{-}}=\lambda_{e^{+}}^{-1}=\exp\frac{\mu}{T}\,,
\end{align}
where $\lambda$ is the chemical fugacity of the system.

We can then parameterize the chemical potential of the $e^{+}e^{-}$ plasma as a function of temperature $\mu\rightarrow\mu(T)$ via the charge neutrality of the universe which implies
\begin{align}
\label{chargeneutrality}
n_{p}=n_{e^{-}}-n_{e^{+}}=\frac{1}{V}\lambda\frac{\partial}{\partial\lambda}\ln\mathcal{Z}_{e^{+}e^{-}}\,.
\end{align}
In \req{chargeneutrality}, $n_{p}$ is the observed total number density of protons in all baryon species. The chemical potential defined in \req{cpotential} is obtained from the requirement that the positive charge of baryons (protons, $\alpha$ particles, light nuclei produced after BBN) is exactly and locally compensated by a tiny net excess of electrons over positrons.
71 changes: 62 additions & 9 deletions novel-fermi-function-refs.bib
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,41 @@ @book{Letessier:2002ony
collection={Cambridge Monographs on Particle Physics, Nuclear Physics and Cosmology},
note={\emph{Open access.} [orig. pub. 2002]}
}
@book{greiner2012thermodynamics,
title={Thermodynamics and statistical mechanics},
author={Greiner, W. and Neise, L. and St{\"o}cker, H.},
year={2012},
publisher={Springer Science \& Business Media},
doi={10.1007/978-1-4612-0827-3},
note={[orig. pub. 1995]}
}
@article{Fromerth:2012fe,
author = "Fromerth, M. J. and Kuznetsova, I. and Labun, L. and Letessier, J. and Rafelski, J.",
editor = "Praszalowicz, M.",
title = "{From Quark-Gluon Universe to Neutrino Decoupling: 200 \ensuremath{<} T \ensuremath{<} 2MeV}",
eprint = "1211.4297",
archivePrefix = "arXiv",
primaryClass = "nucl-th",
doi = "10.5506/APhysPolB.43.2261",
journal = "Acta Phys. Polon. B",
volume = "43",
number = "12",
pages = "2261--2284",
year = "2012"
}
@article{Canetti:2012zc,
author = "Canetti, L. and Drewes, M. and Shaposhnikov, M.",
title = "{Matter and Antimatter in the Universe}",
eprint = "1204.4186",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "TTK-12-04",
doi = "10.1088/1367-2630/14/9/095012",
journal = "New J. Phys.",
volume = "14",
pages = "095012",
year = "2012"
}
@book{Arfken:2011abc,
title={Mathematical methods for physicists: a comprehensive guide},
author={Arfken, G. B. and Weber, H. J. and Harris, F. E.},
Expand All @@ -32,15 +67,18 @@ @book{Melrose:2008abc
publisher={Springer},
doi={10.1007/978-1-4614-4045-1}
}
@unpublished{Steinmetz:2023nsc,
author = "Steinmetz, A. and Yang, C. T. and Rafelski, J.",
title = "{Matter-antimatter origin of cosmic magnetism}",
archivePrefix = "arXiv",
eprint = "2308.14818",
primaryClass = "hep-ph",
year = "2023",
doi = "10.48550/arXiv.2308.14818",
note = "[Submitted to Phys. Rev. D]"
@article{Steinmetz:2023nsc,
author = "Steinmetz, Andrew and Yang, Cheng Tao and Rafelski, Johann",
title = "{Matter-antimatter origin of cosmic magnetism}",
eprint = "2308.14818",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
doi = "10.1103/PhysRevD.108.123522",
journal = "Phys. Rev. D",
volume = "108",
number = "12",
pages = "123522",
year = "2023"
}
@article{Rafelski:2023emw,
author = "Rafelski, J. and Birrell, J. and Steinmetz, A. and Yang, C. T.",
Expand Down Expand Up @@ -137,4 +175,19 @@ @article{Rafelski:2020ajx
volume = "259",
pages = "13001",
year = "2022"
}
@book{Gradshteyn:1943cpj,
author = "Gradshteyn, I. S. and Ryzhik, I. M.",
title = "{Table of Integrals, Series, and Products, 7th edition}",
isbn = "978-0-12-294757-5, 978-0-12-294757-5",
year = "2007",
publisher = "Academic Press",
address = "Burlington, MA"
}
@book{landau2013statistical,
title={Course of Theoretical Physics, Volume 5, Statistical Physics, Part 1, 3rd edition},
author={Landau, Lev Davidovich and Lifshitz, Evgenii Mikhailovich},
year={1980},
publisher={Pergamon Press},
address = "Elmsford, NY"
}
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