Higher-spin theory

<p>Higher-spin theory or higher-spin gravity is a common name for <a href="/facts/Field_theory_(physics)/FJdAKeRA">field theories</a> that contain massless fields of <a href="/facts/Spin_(physics)/4Jvp7e8P">spin</a> greater than two. Usually, the spectrum of such theories contains the <a href="/facts/Graviton/MVJUBjek">graviton</a> as a massless spin-two field, which explains the second name. Massless fields are <a href="/facts/Gauge_theory/fSW3gggv">gauge fields</a> and the theories should be (almost) completely fixed by these higher-spin symmetries. Higher-spin theories are supposed to be consistent <a href="/facts/Quantum/4x5QTxGB">quantum</a> theories and, for this reason, to give examples of <a href="/facts/Quantum_gravity/t7whBMNE">quantum gravity</a>. Most of the interest in the topic is due to the  <a href="/facts/AdS/CFT_correspondence/8Ide9C9m">AdS/CFT correspondence</a> where there is a number of conjectures relating higher-spin theories to weakly coupled <a href="/facts/Conformal_field_theory/McVlk4hR">conformal field theories</a>. It is important to note that only certain parts of these theories are known at present (in particular, standard action principles are not known) and not many examples have been worked out in detail except some specific toy models (such as the higher-spin extension of pure <a href="/facts/Chern%E2%80%93Simons_theory/AQ3Kayn3">Chern–Simons</a>, Jackiw–Teitelboim, selfdual (chiral) and Weyl gravity theories).
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Higher-spin theory open-in-new

Higher-spin theory