The relativistic center of mass in field theory with spin
Abstract In order to unravel the origin of the nucleon spin, one has to study in detail the question of orbital angular momentum, and in particular the reference point about which it is defined. With this in mind, we review the concept of relativistic center of mass, generalize the discussion to the...
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| Format: | Article |
| Language: | English |
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SpringerOpen
2018-09-01
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| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | http://link.springer.com/article/10.1140/epjc/s10052-018-6249-3 |
| _version_ | 1818859760006463488 |
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| author | Cédric Lorcé |
| author_facet | Cédric Lorcé |
| author_sort | Cédric Lorcé |
| collection | DOAJ |
| description | Abstract In order to unravel the origin of the nucleon spin, one has to study in detail the question of orbital angular momentum, and in particular the reference point about which it is defined. With this in mind, we review the concept of relativistic center of mass, generalize the discussion to the case of asymmetric energy-momentum tensors, and establish the link with the light-front formalism. We find that the p-wave in the Dirac plane-wave solutions arises from a relativistic quantum-mechanical effect which forces the canonical reference point to depend on the observer. This explains why longitudinal spin is much simpler to study than transverse spin. It is also the reason behind the observation of induced shifts and distortions in the parton distributions defined within the light-front formalism. |
| first_indexed | 2024-12-19T09:17:18Z |
| format | Article |
| id | doaj.art-0a352ff774974fef8a18a96d1887e5bb |
| institution | Directory Open Access Journal |
| issn | 1434-6044 1434-6052 |
| language | English |
| last_indexed | 2024-12-19T09:17:18Z |
| publishDate | 2018-09-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | European Physical Journal C: Particles and Fields |
| spelling | doaj.art-0a352ff774974fef8a18a96d1887e5bb2022-12-21T20:28:04ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60441434-60522018-09-0178912210.1140/epjc/s10052-018-6249-3The relativistic center of mass in field theory with spinCédric Lorcé0Centre de Physique Théorique, École polytechnique, CNRS, Université Paris-SaclayAbstract In order to unravel the origin of the nucleon spin, one has to study in detail the question of orbital angular momentum, and in particular the reference point about which it is defined. With this in mind, we review the concept of relativistic center of mass, generalize the discussion to the case of asymmetric energy-momentum tensors, and establish the link with the light-front formalism. We find that the p-wave in the Dirac plane-wave solutions arises from a relativistic quantum-mechanical effect which forces the canonical reference point to depend on the observer. This explains why longitudinal spin is much simpler to study than transverse spin. It is also the reason behind the observation of induced shifts and distortions in the parton distributions defined within the light-front formalism.http://link.springer.com/article/10.1140/epjc/s10052-018-6249-3 |
| spellingShingle | Cédric Lorcé The relativistic center of mass in field theory with spin European Physical Journal C: Particles and Fields |
| title | The relativistic center of mass in field theory with spin |
| title_full | The relativistic center of mass in field theory with spin |
| title_fullStr | The relativistic center of mass in field theory with spin |
| title_full_unstemmed | The relativistic center of mass in field theory with spin |
| title_short | The relativistic center of mass in field theory with spin |
| title_sort | relativistic center of mass in field theory with spin |
| url | http://link.springer.com/article/10.1140/epjc/s10052-018-6249-3 |
| work_keys_str_mv | AT cedriclorce therelativisticcenterofmassinfieldtheorywithspin AT cedriclorce relativisticcenterofmassinfieldtheorywithspin |