1 Correction to: Foundations of Physics (2021) 51:7 https://doi.org/10.1007/s10701-021-00415-2

The author would like to correct errors in the formatting of certain upper-lower index pairs in the publication of the original article that arose during the proofing process. The corrected details are given below.

(a) Page 5: “Thus, the components \(a^{\mu }\) of the four-vector a and the entries \(\Lambda _{\nu }^{\mu }\) of the Lorentz-transformation matrix” should be changed to “Thus, the components \(a^{\mu }\) of the four-vector a and the entries \(\underline{\Lambda _{\,\,\nu }^{\mu }}\) of the Lorentz-transformation matrix”.

(b) Page 5: “remembering that these variables are independent of the Lorentz-transformation variables \(\Lambda _{\nu }^{\mu }\)” should be changed to “remembering that these variables are independent of the Lorentz-transformation variables \(\underline{\Lambda _{\,\,\nu }^{\mu }}\)”.

(c) Page 6:

$$\begin{aligned}{}[\sigma _{\mu \nu }]_{\beta }^{\alpha }=-i\delta _{\mu }^{\alpha }\eta _{\nu \beta } +i\eta _{\mu \beta }\delta _{\nu }^{\alpha }. \end{aligned}$$

should be changed to

$$\begin{aligned} \underline{[\sigma _{\mu \nu }]_{\,\,\beta }^{\alpha }}=-i \delta _{\mu }^{\alpha }\eta _{\nu \beta }+i\eta _{\mu \beta }\delta _{\nu }^{\alpha }. \end{aligned}$$

(d) Page 7:

$$\begin{aligned} \frac{1}{2}[\sigma ^{\mu \nu }]_{\beta }^{\alpha }A_{\alpha }^{\beta }=iA^{\mu \nu }, \end{aligned}$$

should be changed to

$$\begin{aligned} \frac{1}{2}\underline{[\sigma ^{\mu \nu }]_{\,\,\beta }^{\alpha } A_{\,\,\alpha }^{\beta }}=iA^{\mu \nu }, \end{aligned}$$

(e) Page 7:

$$\begin{aligned} \frac{1}{2}\mathrm {Tr}[S\dot{\Lambda }\Lambda ^{-1}]\equiv \frac{1}{2} S_{\beta }^{\alpha }\dot{\Lambda }_{\gamma }^{\beta }(\Lambda ^{-1})_{\alpha }^{\gamma }. \end{aligned}$$

should be changed to

$$\begin{aligned} \frac{1}{2}\mathrm {Tr}[S\dot{\Lambda }\Lambda ^{-1}]\equiv \frac{1}{2} \underline{S_{\,\,\beta }^{\alpha }\dot{\Lambda }_{\,\, \gamma }^{\beta }(\Lambda ^{-1})_{\,\,\alpha }^{\gamma }}. \end{aligned}$$

(f) Page 11:

$$\begin{aligned} \bar{p}^{\mu }=\bar{\Lambda }_{\nu }^{\mu }p_{0}^{\nu }, \end{aligned}$$

should be changed to

$$\begin{aligned} \bar{p}^{\mu }=\underline{\bar{\Lambda }_{\,\,\nu }^{\mu }}p_{0}^{\nu }, \end{aligned}$$