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# Latex symbol Planck constant h

How to write Latex symbol Latex Planck constant h, Planck constant reduced: \hbar, \hslash

## Commands \hbar and \hslash

The reduced Planck constant, often denoted \hbar, is an important physical constant in quantum mechanics and particle physics. It is defined as the Planck constant divided by 2π:


\begin{equation*}
\hbar = \frac{h}{2\pi}
\end{equation*}


where h is the Planck constant.

The \hbar command in LaTeX produces the symbol for the reduced Planck constant:


\hbar


This produces:

$$\begin{equation*} \hbar = \frac{h}{2\pi} \end{equation*}$$

The \hslash command in LaTeX also produces the symbol for the reduced Planck constant:


\hslash


This produces:

$$\begin{equation*} \hslash = \frac{h}{2\pi} \end{equation*}$$

Both commands produce the same symbol, but some authors prefer to use one or the other depending on the context.