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Plahte diagrams for string scattering amplitudes (2021)
Journal Article
Srisangyingcharoen, P., & Mansfield, P. (2021). Plahte diagrams for string scattering amplitudes. Journal of High Energy Physics, 2021(4), Article 17. https://doi.org/10.1007/jhep04%282021%29017

Plahte identities are monodromy relations between open string scattering amplitudes at tree level derived from the Koba-Nielsen formula. We represent these identities by polygons in the complex plane. These diagrams make manifest the appearance of si... Read More about Plahte diagrams for string scattering amplitudes.

Intersection of world-lines on curved surfaces and path-ordering of the Wilson loop (2018)
Journal Article
Curry, C., & Mansfield, P. (2018). Intersection of world-lines on curved surfaces and path-ordering of the Wilson loop. Journal of High Energy Physics, 2018(6), Article 81. https://doi.org/10.1007/jhep06%282018%29081

We study contact interactions for long world-lines on a curved surface, focusing on the average number of times two world-lines intersect as a function of their end-points. The result can be used to extend the concept of path-ordering, as employed in... Read More about Intersection of world-lines on curved surfaces and path-ordering of the Wilson loop.

Entanglement of self-interacting scalar fields in an expanding spacetime (2016)
Journal Article
Alexander, H., de Souza, G., Mansfield, P., da Paz, I., & Sampaio, M. (2016). Entanglement of self-interacting scalar fields in an expanding spacetime. European Physical Society Letters, 115(1), Article 10006. https://doi.org/10.1209/0295-5075/115/10006

We evaluate self-interaction effects on the quantum correlations of field modes of opposite momenta for scalar $\lambda \phi^4$ theory in a two-dimensional asymptotically flat Robertson-Walker spacetime. Such correlations are encoded both in the von... Read More about Entanglement of self-interacting scalar fields in an expanding spacetime.

Alice and Bob in an expanding spacetime (2015)
Journal Article
Alexander, H., de Souza, G., Mansfield, P., & Sampaio, M. (2015). Alice and Bob in an expanding spacetime. European Physical Society Letters, 111(6), Article 60001. https://doi.org/10.1209/0295-5075/111/60001

We investigate the teleportation of a qubit between two observers Alice and Bob in an asymptotically flat Robertson-Walker expanding spacetime. We use scalar or fermionic field modes inside Alice's and Bob's ideal cavities and show the degradation of... Read More about Alice and Bob in an expanding spacetime.

QED as the tensionless limit of the spinning string with contact interaction (2015)
Journal Article
Edwards, J. P., & Mansfield, P. (2015). QED as the tensionless limit of the spinning string with contact interaction. Physics Letters B, 746, 335-340. https://doi.org/10.1016/j.physletb.2015.05.024

QED with spinor matter is argued to correspond to the tensionless limit of spinning strings with contact interactions. The strings represent electric lines of force with charges at their ends. The interaction is constructed from a delta-function on t... Read More about QED as the tensionless limit of the spinning string with contact interaction.

The fermion content of the Standard Model from a simple world-line theory (2015)
Journal Article
Mansfield, P. (2015). The fermion content of the Standard Model from a simple world-line theory. Physics Letters B, 743, 353-356. https://doi.org/10.1016/j.physletb.2015.02.061

We describe a simple model that automatically generates the sum over gauge group representations and chiralities of a single generation of fermions in the Standard Model, augmented by a sterile neutrino. The model is a modification of the world-line... Read More about The fermion content of the Standard Model from a simple world-line theory.

Delta-function interactions for the bosonic and spinning strings and the generation of Abelian gauge theory (2015)
Journal Article
Edwards, J., & Mansfield, P. (2015). Delta-function interactions for the bosonic and spinning strings and the generation of Abelian gauge theory. Journal of High Energy Physics, 2015(1), Article 127. https://doi.org/10.1007/jhep01%282015%29127

We construct contact interactions for bosonic and spinning strings. In the tensionless limit of the spinning string this reproduces the super-Wilson loop that couples spinor matter to Abelian gauge theory. Adding boundary terms that quantise the moti... Read More about Delta-function interactions for the bosonic and spinning strings and the generation of Abelian gauge theory.

Faraday's Lines of Force as Strings: from Gauss' Law to the Arrow of Time (2012)
Journal Article
Mansfield, P. (2012). Faraday's Lines of Force as Strings: from Gauss' Law to the Arrow of Time. Journal of High Energy Physics, 2012(10), Article 149. https://doi.org/10.1007/jhep10%282012%29149

We reformulate classical electromagnetism as the statistical mechanics of lines of electric flux with dynamics described by the string action in four dimensions. The retarded solution to Maxwell’s equations emerges naturally as an average over a micr... Read More about Faraday's Lines of Force as Strings: from Gauss' Law to the Arrow of Time.

Symmetries of Self-Dual Yang-Mills Equations Dimensionally Reduced From (2,2) Space-time (2011)
Journal Article
Mansfield, P., & Wardlow, A. (2011). Symmetries of Self-Dual Yang-Mills Equations Dimensionally Reduced From (2,2) Space-time. Journal of High Energy Physics, 2011(01), Article 097. https://doi.org/10.1007/jhep01%282011%29097

We construct infinite-dimensional symmetries of the two dimensional equation which results from the dimensional reduction of the self-duality condition in (2, 2) signature space-time. These are symmetries of the dimensionally reduced Chalmers-Siegel... Read More about Symmetries of Self-Dual Yang-Mills Equations Dimensionally Reduced From (2,2) Space-time.

Infinite dimensional symmetries of self-dual Yang-Mills. (2009)
Journal Article
Mansfield, P., & Wardlow, A. (2009). Infinite dimensional symmetries of self-dual Yang-Mills. Journal of High Energy Physics, 2009(08), Article 072. https://doi.org/10.1088/1126-6708/2009/08/072

We construct symmetries of the Chalmers-Siegel action describing self-dual Yang-Mills theory using a canonical transformation to a free theory. The symmetries form an infinite dimensional Lie algebra in the group algebra of isometries.

S-matrix equivalence theorem evasion and dimensional regularisation with the canonical MHV lagrangian (2007)
Journal Article
Ettle, J. H., Fu, C., Fudger, J. P., Mansfield, P. R., & Morris, T. R. (2007). S-matrix equivalence theorem evasion and dimensional regularisation with the canonical MHV lagrangian. Journal of High Energy Physics, 2007(05),

We demonstrate that the canonical change of variables that yields the MHV lagrangian, also provides contributions to scattering amplitudes that evade the equivalence theorem. This `ET evasion' in particular provides the tree-level (−++) amplitude, wh... Read More about S-matrix equivalence theorem evasion and dimensional regularisation with the canonical MHV lagrangian.

Solving the anharmonic oscillator: Tuning the boundary condition. (2007)
Journal Article
Leonard, D., & Mansfield, P. (2007). Solving the anharmonic oscillator: Tuning the boundary condition. Journal of Physics A: Mathematical and Theoretical, 40(33),

We outline a remarkably efficient method for generating solutions to quantum anharmonic oscillators with an x2M potential. We solve the Schroedinger equation in terms of a free parameter which is then tuned to give the correct boundary condition by g... Read More about Solving the anharmonic oscillator: Tuning the boundary condition..

The Lagrangian origin of MHV rules (2006)
Journal Article
Mansfield, P. (2006). The Lagrangian origin of MHV rules. Journal of High Energy Physics, 2006(03), https://doi.org/10.1088/1126-6708/2006/03/037

We construct a canonical transformation that takes the usual Yang-Mills action into one whose Feynman diagram expansion generates the MHV rules. The off-shell continuation appears as a natural consequence of using light-front quantisation surfaces. T... Read More about The Lagrangian origin of MHV rules.

Timelike T-duality in the string field Schrödinger functional (2005)
Journal Article
Ilderton, A., & Mansfield, P. (2005). Timelike T-duality in the string field Schrödinger functional. Journal of High Energy Physics, 2005(10), https://doi.org/10.1088/1126-6708/2005/10/016

Timelike T-duality of string theory appears as a symmetry of time evolution in string field theory, exchanging evolution through times t and 1/t, and exchanging boundary states with backgrounds. This is demonstrated by constructing the string field S... Read More about Timelike T-duality in the string field Schrödinger functional.

Time evolution in string field theory and T-duality (2005)
Journal Article
Ilderton, A., & Mansfield, P. (2005). Time evolution in string field theory and T-duality. Physics Letters B, 607(3-4), 294-301. https://doi.org/10.1016/j.physletb.2004.12.066

The time evolution operator (Schrödinger functional) of quantum field theory can be expressed in terms of first quantised particles moving on S1/Z2. We give a graphical derivation of this that generalises to second quantised string theory. T-duality... Read More about Time evolution in string field theory and T-duality.

Solving the functional Schrödinger equation: Yang-Mills string tension and surface critical scaling (2004)
Journal Article
Mansfield, P. (2004). Solving the functional Schrödinger equation: Yang-Mills string tension and surface critical scaling. Journal of High Energy Physics, 2004(04), https://doi.org/10.1088/1126-6708/2004/04/059

Motivated by a heuristic model of the Yang-Mills vacuum that accurately describes the string-tension in three dimensions we develop a systematic method for solving the functional Schrödinger equation in a derivative expansion. This is applied to the... Read More about Solving the functional Schrödinger equation: Yang-Mills string tension and surface critical scaling.

The boundary Weyl anomaly in the N = 4 SYM / type IIB supergravity correspondence (2004)
Journal Article
Mansfield, P., Nolland, D., & Ueno, T. (2004). The boundary Weyl anomaly in the N = 4 SYM / type IIB supergravity correspondence. Journal of High Energy Physics, 2004(01), https://doi.org/10.1088/1126-6708/2004/01/013

We give a complete account of the Schrödinger representation approach to the calculation of the Weyl anomaly of = 4 SYM from the AdS/CFT correspondence. On the AdS side, the 1/N2 correction to the leading order result receives contributions from all... Read More about The boundary Weyl anomaly in the N = 4 SYM / type IIB supergravity correspondence.

A Large-D Weyl Invariant String in Anti-de Sitter Space. (2003)
Journal Article
Davies, I., & Mansfield, P. (2003). A Large-D Weyl Invariant String in Anti-de Sitter Space. Modern Physics Letters A, 18(22), 1517-1522. https://doi.org/10.1142/s021773230301123x

The bosonic string propagating in AdSD+1 is made Weyl invariant to leading and sub-leading order in large D by a ghost–matter coupling that despite modifying the target-space still preserves the Poincaré symmetry of the boundary.

Order 1/N3 corrections to the conformal anomaly of the (2,0) theory in six dimensions (2003)
Journal Article
Mansfield, P., Nolland, D., & Ueno, T. (2003). Order 1/N3 corrections to the conformal anomaly of the (2,0) theory in six dimensions. Physics Letters B, 566(1-2), 157-163. https://doi.org/10.1016/s0370-2693%2803%2900777-9

Using Supergravity on AdS7×S4 we calculate the bulk one-loop contribution to the conformal anomaly of the (2,0) theory describing N coincident M5 branes. When this is added to the tree-level result, and an additional subleading order contribution cal... Read More about Order 1/N3 corrections to the conformal anomaly of the (2,0) theory in six dimensions.