SpinorVBar[p, m]
denotes a \bar{v}(p,m)-spinor that depends on the 4-dimensional momentum p.
Overview, Spinor, SpinorUBar, SpinorU, SpinorV, SpinorUBarD, SpinorUD, SpinorVD, SpinorVBarD.
[p, m] SpinorVBar
\bar{v}(p,m)
[p, m] // FCI // StandardForm
SpinorVBar
(*Spinor[-Momentum[p], m, 1]*)
[p] SpinorVBar
\bar{v}(p)
[p] // FCI // StandardForm
SpinorVBar
(*Spinor[-Momentum[p], 0, 1]*)
[p] . GS[p]
SpinorVBar
[%] DiracEquation
\bar{v}(p).\left(\bar{\gamma }\cdot \overline{p}\right)
0