<sod>Not all quantities are invariant in the form as shown above, for example orbital [[angular momentum]] {{math|'''L'''}} does not have a timelike quantity, and neither does the [[electric field]] {{math|'''E'''}} nor the [[magnetic field]] {{math|'''B'''}}. The definition of angular momentum is {{math|'''L''' {{=}} '''r''' × '''p'''}}, and in a boosted frame the altered angular momentum is {{math|'''L'''&prime; {{=}} '''r'''&prime; × '''p'''&prime;}}. Applying this definition using the transformations of coordinates and momentum leads to the transformation of angular momentum. It turns out {{math|'''L'''}} transforms with another vector quantity {{math|'''N''' {{=}} (''E''/''c''<sup>2</sup>)'''r''' − ''t'''''p'''}} related to boosts, see [[relativistic angular momentum]] for details. For the case of the {{math|'''E'''}} and {{math|'''B'''}} fields, the transformations cannot be obtained as directly using vector algebra. The Lorentz force is the definition of these fields, and in {{math|''F''}} it is {{math|'''F''' {{=}} ''q''('''E''' + '''v'''×'''B''')}} while in {{math|''F''&prime;}} it is {{math|'''F'''&prime; {{=}} ''q''('''E'''&prime; + '''v'''&prime;×'''B'''&prime;)}}. A method of deriving the EM field transformations in an efficient way which also illustrates the unit of the electromagnetic field uses tensor algebra, [[Lorentz transformation#Transformation of the electromagnetic field|given below]].<eod>
<sod>Not all quantities are invariant in the form as shown above, for example orbital [[angular momentum]] {{math|'''L'''}} does not have a timelike quantity, and neither does the [[electric field]] {{math|'''E'''}} nor the [[magnetic field]] {{math|'''B'''}}. The definition of angular momentum is {{math|'''L''' {{=}} '''r''' × '''p'''}}, and in a boosted frame the altered angular momentum is {{math|'''L'''&prime; {{=}} '''r'''&prime; × '''p'''&prime;}}. Applying this definition using the transformations of coordinates and momentum leads to the transformation of angular momentum. It turns out {{math|'''L'''}} transforms with another vector quantity {{math|'''N''' {{=}} (''E''/''c''<sup>2</sup>)'''r''' − ''t'''''p'''}} related to boosts, see [[relativistic angular momentum]] for details. For the case of the {{math|'''E'''}} and {{math|'''B'''}} fields, the transformations cannot be obtained as directly using vector algebra. The [[Lorentz force]] is the definition of these fields, and in {{math|''F''}} it is {{math|'''F''' {{=}} ''q''('''E''' + '''v'''×'''B''')}} while in {{math|''F''&prime;}} it is {{math|'''F'''&prime; {{=}} ''q''('''E'''&prime; + '''v'''&prime;×'''B'''&prime;)}}. A method of deriving the EM field transformations in an efficient way which also illustrates the unit of the electromagnetic field uses tensor algebra, [[Lorentz transformation#Transformation of the electromagnetic field|given below]].<eod>