Undergrad Boost Generators: Physical Meaning & Observable Quantities

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Boosts in the Poincare group are linked to physical quantities, similar to time translation with energy and space translations with momentum. The distinction between boosts and rotations is frame-dependent, necessitating a unified understanding of both concepts. This unification leads to the identification of a relativistic angular momentum tensor that corresponds to the generators of boosts and rotations. Understanding this relationship enhances the comprehension of observable quantities in relativistic physics. The discussion emphasizes the importance of integrating boosts with rotations for a complete physical interpretation.
nicholas_eng
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Do the generators of boosts correspond to anything physical?
So, all of the generators of the Poincare group are associated with pretty well-known physical quantities. Time translation is associated with energy, space translations with momentum, rotations with angular momentum, and boosts... well, boosts are generated by the "generators of boosts". Do they correspond to any observable?
 
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A proper understanding of boosts in the context of your question requires unifying them with rotations; note that the split between what is a "boost" and what is a "rotation" is frame-dependent. When we unify boosts and rotations, we find that there is a relativistic angular momentum tensor that corresponds to the boost/rotation generators. Wikipedia has a brief discussion:

https://en.wikipedia.org/wiki/Relat...e_generator_of_spacetime_boosts_and_rotations
 
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