<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-06-27T13:58:27Z</responseDate><request verb="GetRecord" identifier="oai:docta.ucm.es:20.500.14352/4476" metadataPrefix="marc">https://docta.ucm.es/rest/oai/request</request><GetRecord><record><header><identifier>oai:docta.ucm.es:20.500.14352/4476</identifier><datestamp>2023-08-26T12:10:10Z</datestamp><setSpec>com_20.500.14352_14</setSpec><setSpec>col_20.500.14352_15</setSpec></header><metadata><record xmlns="http://www.loc.gov/MARC21/slim" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://www.loc.gov/MARC21/slim http://www.loc.gov/standards/marcxml/schema/MARC21slim.xsd">
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      <subfield code="a">Cabral, Francisco</subfield>
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      <subfield code="a">Lobo, Francisco S. N.</subfield>
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      <subfield code="a">Rubiera García, Diego</subfield>
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      <subfield code="c">2021-10-07</subfield>
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      <subfield code="a">In this work, we investigate the effects of the torsion-fermionic interaction on the energy levels of fermions within a Riemann-Cartan geometry using a model-independent approach. We consider the case of fermions minimally coupled to the background torsion as well as non-minimal extensions via additional couplings with the vector and axial fermionic currents which include parity-breaking interactions. In the limit of zero-curvature, and for the cases of constant and spherically symmetric torsion, we find a Zeeman-like effect on the energy levels of fermions and anti-fermions depending on whether they are aligned/anti-aligned with respect to the axial vector part of the torsion (or to specific combination of torsion quantities), and determine the corresponding fine-structure energy transitions. We also discuss non-minimal couplings between fermionic fields and torsion within the Einstein-Cartan theory and its extension to include the (parity-breaking) Holst term. Finally we elaborate on the detection of torsion effects related to the splitting of energy levels in astrophysics, cosmology and solid state physics using current capabilities.</subfield>
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      <subfield code="a">0264-9381</subfield>
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      <subfield code="a">10.1088/1361-6382/ac1cca</subfield>
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      <subfield code="a">https://hdl.handle.net/20.500.14352/4476</subfield>
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      <subfield code="a">http://dx.doi.org/10.1088/1361-6382/ac1cca</subfield>
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      <subfield code="a">https://iopscience.iop.org/</subfield>
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      <subfield code="a">Imprints from a Riemann-Cartan space-time on the energy levels of Dirac spinors</subfield>
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