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-rw-r--r--physics/units.page14
1 files changed, 7 insertions, 7 deletions
diff --git a/physics/units.page b/physics/units.page
index 385136c..bfc78bc 100644
--- a/physics/units.page
+++ b/physics/units.page
@@ -3,11 +3,11 @@ format: rst
categories: physics
toc: no
...
+
======================
Units
======================
-.. contents::
SI Units
--------------------
@@ -26,7 +26,7 @@ Natural Units
Natural units are a system of units which replace (or re-scale) the usual mass,
length, and time bases with quantities which have "natural" (physical)
constants associated with them. The two constants usually chosen are the speed
-of light (c) and Plank's constant (:m:`$\hbar$`); the gravitational constant
+of light (c) and Plank's constant ($\hbar$); the gravitational constant
(G) is a possibility for the third constant/unit, but energy (in
electron-volts: eV) is often used instead because it gives more useful
relations and because there is no accepted theory of quantum gravity to unite
@@ -36,18 +36,18 @@ Working with natural units simplifies physical relations and equations because
many conversion factors drop out.
Given the relations between cgs units (gm, cm, sec) and natural units (c,
-:m:`$\hbar$` , eV), we can find the natural units of an arbitrary quantity
-:m:`$[Q]=[gm]^{a}[cm]^{b}[sec]^{c}=[c]^{\alpha}[\hbar]^{\beta}[eV]^{\gamma}$`:
+$\hbar$ , eV), we can find the natural units of an arbitrary quantity
+$[Q]=[gm]^{a}[cm]^{b}[sec]^{c}=[c]^{\alpha}[\hbar]^{\beta}[eV]^{\gamma}$:
-:m:`$$(\alpha,\beta,\gamma)=\left(\begin{array}{ccc} -2 & 1 & 0\\ 0 & 1 & 1\\ 1 & -1 & -1\end{array}\right)\left(\begin{array}{c} a\\ b\\ c\end{array}\right)=(-2a+b,b+c,a-b-c)$$`
+$$(\alpha,\beta,\gamma)=\left(\begin{array}{ccc} -2 & 1 & 0\\ 0 & 1 & 1\\ 1 & -1 & -1\end{array}\right)\left(\begin{array}{c} a\\ b\\ c\end{array}\right)=(-2a+b,b+c,a-b-c)$$
or in reverse:
-:m:`$$(a,b,c)=\left(\begin{array}{ccc} 0 & 1 & 1\\ 1 & 2 & 2\\ -1 & -1 & -2\end{array}\right)\left(\begin{array}{c} \alpha\\ \beta\\ \gamma\end{array}\right)=(\beta+\gamma,\alpha+2\beta+\gamma,-\alpha-\beta-2\gamma)$$`
+$$(a,b,c)=\left(\begin{array}{ccc} 0 & 1 & 1\\ 1 & 2 & 2\\ -1 & -1 & -2\end{array}\right)\left(\begin{array}{c} \alpha\\ \beta\\ \gamma\end{array}\right)=(\beta+\gamma,\alpha+2\beta+\gamma,-\alpha-\beta-2\gamma)$$
Plank Units
----------------
-Plank units (defined by Plank soon after defining his constant :m:`$\hbar$`) are a version of _`Natural Units` using the gravitational constant G as the the
+Plank units (defined by Plank soon after defining his constant $\hbar$) are a version of _`Natural Units` using the gravitational constant G as the the
third unit (instead of the common measure of energy). When converted back into
mass-length-time units we get three quantities which define the "Plank Scale",
which may provide estimation of the domain where quantum gravity effects become