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In theoretical physics, a **no-go theorem** is a theorem that states that a particular situation is not physically possible. This type of theorem imposes boundaries on certain mathematical or physical possibilities via a proof of contradiction.^{[1]}^{[2]}^{[3]}

Full descriptions of the no-go theorems named below are given in other articles linked to their names. A few of them are broad, general categories under which several theorems fall. Other names are broad and general-sounding but only refer to a single theorem.

- Antidynamo theorems are a general category of theorems that restrict the type of magnetic fields that can be produced by dynamo action.
- Earnshaw's theorem states that a collection of point charges cannot be maintained in a stable stationary equilibrium configuration solely by the electrostatic interaction of the charges.

- Bell's theorem
^{[1]} - Kochen–Specker theorem
^{[1]} - PBR theorem
- No-hiding theorem
- No-cloning theorem
- Quantum no-deleting theorem
- No-teleportation theorem
- No-broadcast theorem
- The no-communication theorem in quantum information theory gives conditions under which instantaneous transfer of information between two observers is impossible.
- No-programming theorem
^{[4]}

- Weinberg–Witten theorem states that massless particles (either composite or elementary) with spin cannot carry a Lorentz-covariant current, while massless particles with spin cannot carry a Lorentz-covariant stress-energy. It is usually interpreted to mean that the graviton ( ) in a relativistic quantum field theory cannot be a composite particle.
- Nielsen–Ninomiya theorem limits when it is possible to formulate a chiral lattice theory for fermions.
- Haag's theorem states that the interaction picture does not exist in an interacting, relativistic, quantum field theory (QFT).
^{[5]}^{[1]} - Hegerfeldt's theorem implies that localizable free particles are incompatible with causality in relativistic quantum theory.
^{[1]} - Coleman–Mandula theorem states that "space-time and internal symmetries cannot be combined in any but a trivial way".
- Haag–Łopuszański–Sohnius theorem is a generalisation of the Coleman–Mandula theorem.
- Goddard–Thorn theorem
- Maldacena–Nunez no-go theorem: any compactification of type IIB string theory on an internal compact space with no brane sources will necessarily have a trivial warp factor and trivial fluxes.
^{[6]} - Reeh–Schlieder theorem
^{[1]}

In mathematics there is the concept of proof of impossibility referring to problems impossible to solve. The difference between this impossibility and that of the no-go theorems is that a proof of impossibility states a category of logical proposition that may never be true; a no-go theorem instead presents a sequence of events that may never occur.

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^{a}^{b}^{c}^{d}^{e}^{f}Andrea Oldofredi (2018). "No-Go Theorems and the Foundations of Quantum Physics".*Journal for General Philosophy of Science*.**49**(3): 355–370. arXiv:1904.10991. doi:10.1007/s10838-018-9404-5. **^**Federico Laudisa (2014). "Against the No-Go Philosophy of Quantum Mechanics".*European Journal for Philosophy of Science*.**4**(1): 1–17. arXiv:1307.3179. doi:10.1007/s13194-013-0071-4.**^**Radin Dardashti (2021-02-21). "No-go theorems: What are they good for?".*Studies in History and Philosophy of Science*.**4**(1): 47–55. arXiv:2103.03491. Bibcode:2021SHPSA..86...47D. doi:10.1016/j.shpsa.2021.01.005. PMID 33965663.**^**Nielsen, M.A.; Chuang, Isaac L. (1997-07-14). "Programmable quantum gate arrays".*Physical Review Letters*.**79**(2): 321–324. arXiv:quant-ph/9703032. Bibcode:1997PhRvL..79..321N. doi:10.1103/PhysRevLett.79.321. S2CID 119447939.**^**Haag, Rudolf (1955). "On quantum field theories" (PDF).*Matematisk-fysiske Meddelelser*.**29**: 12.**^**Becker, K.; Becker, M.; Schwarz, J.H. (2007). "10".*String Theory and M-Theory*. Cambridge: Cambridge University Press. pp. 480–482. ISBN 978-0521860697.

- Quotations related to No-go theorem at Wikiquote
- Sadhukhan, Debasis; Roy, Sudipto Singha; Rakshit, Debraj; Sen(De), Aditi; Sen, Ujjwal (2015). "Beating no-go theorems by engineering defects in quantum spin models".
*New Journal of Physics*.**17**(4): 043013. arXiv:1406.7239. Bibcode:2015NJPh...17d3013S. doi:10.1088/1367-2630/17/4/043013.