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    "level": "reference",
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      "Spin+(3,1)",
      "Lorentz spin cover"
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    "searchTerms": [],
    "tags": [
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      "Spinors"
    ],
    "summary": "As a real Lie group, SL(2,ℂ) is the double cover of the identity component SO⁺(3,1) of the Lorentz group.",
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        "label": "Center",
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        "label": "Compact",
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          {
            "text": "SL(2,C) is being used as a real six-dimensional Lie group. Its real Lie algebra complexifies to sl(2,C) ⊕ sl(2,C), rather than to a single A₁ factor. Finite-dimensional complex irreducibles consequently carry two nonnegative half-integer labels (jL,jR), with dimension (2jL+1)(2jR+1).",
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