John March-Russell | University of Oxford (original) (raw)

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Papers by John March-Russell

AIP Conference Proceedings, 2001

The properties and interactions of gauge vortices are discussed in a variety of contexts. When qu... more The properties and interactions of gauge vortices are discussed in a variety of contexts. When quarks and leptons propagate in the background of a grand unified cosmic string, various baryon number violating processes can occur. We argue that, because of the pure gauge field that surrounds the string, the cross-sections for these processes are generically enhanced by large factors over

We consider a U(1) gauge theory on the five dimensional orbifold mathcalM4timesS1/Z2\mathcal{M}_4\times S^1/Z_2mathcalM4timesS1/Z2, w... more We consider a U(1) gauge theory on the five dimensional orbifold mathcalM4timesS1/Z2\mathcal{M}_4\times S^1/Z_2mathcalM_4timesS1/Z2, where A5A_5A5 has even Z2Z_2Z2 parity. This leads to a light pseudoscalar degree of freedom W(x)W(x)W(x) in the effective 4D theory below the compactification scale arising from a gauge-invariant brane-to-brane Wilson line. As noted by Arkani-Hamed et al in the non-supersymmetric S1S^1S1 case the 5D bulk gauge-invariance of the underlying theory together with the non-local nature of the Wilson line field leads to the protection of the 4D theory of W(x)W(x)W(x) from possible large global-symmetry violating quantum gravitational effects. We study the S1/Z2S^1/Z_2S1/Z_2 theory in detail, in particular developing the supersymmetric generalization of this construction, involving a pseudoscalar Goldstone field (the `axion') and its scalar and fermion superpartners (`saxion' and `axino'). The global nature of W(x)W(x)W(x) implies the absence of independent Kaluza-Klein excitations of its component fields. The non...

Physical Review D, 2003

... Rev. Lett. 89, 151302 (2002) [SPIRES]; SC Park and HS Song, hep-ph/0111069; Y. Uehara, hep-ph... more ... Rev. Lett. 89, 151302 (2002) [SPIRES]; SC Park and HS Song, hep-ph/0111069; Y. Uehara, hep-ph/0205068; hep-ph/0205199; AV Kotwal and C. Hays, Phys. Rev. ... S. Chandrasekhar, The Mathematical Theory of Black Holes (Oxford University Press, New York, 1983). ...

Physics World, 2000

The possibility of extra dimensions, beyond the three dimensions of space of our everyday experie... more The possibility of extra dimensions, beyond the three dimensions of space of our everyday experience, sometimes crops up as a convenient, if rather vague, plot in science fiction. In science, however, the idea of extra dimensions has a ...

Physical Review Letters, 2015

We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs soluti... more We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20 GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors.

Physical review. B, Condensed matter, 1989

We consider some observable consequences of the possible breaking of the discrete space-time symm... more We consider some observable consequences of the possible breaking of the discrete space-time symmetries P and T in high-T c superconducting materials, as occurs in anyon models. It is argued, within these models, that at least two species of anyons are expected to occur, ...

Journal of High Energy Physics, 2004

... Towards a theory of flavor from orbifold GUTs Lawrence ... breaking. Most notorious is the do... more ... Towards a theory of flavor from orbifold GUTs Lawrence ... breaking. Most notorious is the doublet-triplet splitting problem of SU(5) and other GUTs. ...

Physical Review Letters, 1988

p under the action of time reversal T, in such a theory the question of T invariance becomes invo... more p under the action of time reversal T, in such a theory the question of T invariance becomes involved with the dynamical issue of what are the allowable values of the charge. We show how cross sections develop T-violating terms for" forbidden" values of the charge. ...

Physical Review Letters, 2000

Arxiv preprint arXiv: …, 2010

Page 1. Preprint typeset in JHEP style - HYPER VERSION SU-ITP-10-18 OUTP-10-10P Axion-Assisted El... more Page 1. Preprint typeset in JHEP style - HYPER VERSION SU-ITP-10-18 OUTP-10-10P Axion-Assisted Electroweak Baryogenesis Nathaniel Craig Institute for Theoretical Physics, Stanford University, Stanford, CA 94306, USA E-mail: ncraig@stanford.edu ...

Yuri Golfand Memorial Volume, 2000

Page 1. arXiv:hep-th/9908146v1 21 Aug 1999 CERN-TH-99-219 SU-ITP-99/38 LBNL-44031 Logarithmic Uni... more Page 1. arXiv:hep-th/9908146v1 21 Aug 1999 CERN-TH-99-219 SU-ITP-99/38 LBNL-44031 Logarithmic Unification From Symmetries Enhanced in the Sub-Millimeter Infrared ∗ Nima Arkani–Hamed ∗∗ , Savas ...

Physical Review D, 2007

ABSTRACT We study the predictions of holographic QCD for various observable four-point quark flav... more ABSTRACT We study the predictions of holographic QCD for various observable four-point quark flavour current-current correlators. The dual 5-dimensional bulk theory we consider is a SU(3)LtimesSU(3)RSU(3)_L \times SU(3)_RSU(3)LtimesSU(3)R Yang Mills theory in a slice of AdS5AdS_5AdS5 spacetime with boundaries. Particular UV and IR boundary conditions encode the spontaneous breaking of the dual 4D global chiral symmetry down to the SU(3)VSU(3)_VSU(3)V subgroup. We explain in detail how to calculate the 4D four-point quark flavour current-current correlators using the 5D holographic theory, including interactions. We use these results to investigate predictions of holographic QCD for the DeltaI=1/2\Delta I = 1/2DeltaI=1/2 rule for kaon decays and the BKB_KBK parameter. The results agree well in comparison with experimental data, with an accuracy of 25% or better. The holographic theory automatically includes the contributions of the meson resonances to the four-point correlators. The correlators agree well in the low-momentum and high-momentum limit, in comparison with chiral perturbation theory and perturbative QCD results, respectively.

AIP Conference Proceedings, 2001

The properties and interactions of gauge vortices are discussed in a variety of contexts. When qu... more The properties and interactions of gauge vortices are discussed in a variety of contexts. When quarks and leptons propagate in the background of a grand unified cosmic string, various baryon number violating processes can occur. We argue that, because of the pure gauge field that surrounds the string, the cross-sections for these processes are generically enhanced by large factors over

We consider a U(1) gauge theory on the five dimensional orbifold mathcalM4timesS1/Z2\mathcal{M}_4\times S^1/Z_2mathcalM4timesS1/Z2, w... more We consider a U(1) gauge theory on the five dimensional orbifold mathcalM4timesS1/Z2\mathcal{M}_4\times S^1/Z_2mathcalM_4timesS1/Z2, where A5A_5A5 has even Z2Z_2Z2 parity. This leads to a light pseudoscalar degree of freedom W(x)W(x)W(x) in the effective 4D theory below the compactification scale arising from a gauge-invariant brane-to-brane Wilson line. As noted by Arkani-Hamed et al in the non-supersymmetric S1S^1S1 case the 5D bulk gauge-invariance of the underlying theory together with the non-local nature of the Wilson line field leads to the protection of the 4D theory of W(x)W(x)W(x) from possible large global-symmetry violating quantum gravitational effects. We study the S1/Z2S^1/Z_2S1/Z_2 theory in detail, in particular developing the supersymmetric generalization of this construction, involving a pseudoscalar Goldstone field (the `axion') and its scalar and fermion superpartners (`saxion' and `axino'). The global nature of W(x)W(x)W(x) implies the absence of independent Kaluza-Klein excitations of its component fields. The non...

Physical Review D, 2003

... Rev. Lett. 89, 151302 (2002) [SPIRES]; SC Park and HS Song, hep-ph/0111069; Y. Uehara, hep-ph... more ... Rev. Lett. 89, 151302 (2002) [SPIRES]; SC Park and HS Song, hep-ph/0111069; Y. Uehara, hep-ph/0205068; hep-ph/0205199; AV Kotwal and C. Hays, Phys. Rev. ... S. Chandrasekhar, The Mathematical Theory of Black Holes (Oxford University Press, New York, 1983). ...

Physics World, 2000

The possibility of extra dimensions, beyond the three dimensions of space of our everyday experie... more The possibility of extra dimensions, beyond the three dimensions of space of our everyday experience, sometimes crops up as a convenient, if rather vague, plot in science fiction. In science, however, the idea of extra dimensions has a ...

Physical Review Letters, 2015

We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs soluti... more We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20 GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors.

Physical review. B, Condensed matter, 1989

We consider some observable consequences of the possible breaking of the discrete space-time symm... more We consider some observable consequences of the possible breaking of the discrete space-time symmetries P and T in high-T c superconducting materials, as occurs in anyon models. It is argued, within these models, that at least two species of anyons are expected to occur, ...

Journal of High Energy Physics, 2004

... Towards a theory of flavor from orbifold GUTs Lawrence ... breaking. Most notorious is the do... more ... Towards a theory of flavor from orbifold GUTs Lawrence ... breaking. Most notorious is the doublet-triplet splitting problem of SU(5) and other GUTs. ...

Physical Review Letters, 1988

p under the action of time reversal T, in such a theory the question of T invariance becomes invo... more p under the action of time reversal T, in such a theory the question of T invariance becomes involved with the dynamical issue of what are the allowable values of the charge. We show how cross sections develop T-violating terms for" forbidden" values of the charge. ...

Physical Review Letters, 2000

Arxiv preprint arXiv: …, 2010

Page 1. Preprint typeset in JHEP style - HYPER VERSION SU-ITP-10-18 OUTP-10-10P Axion-Assisted El... more Page 1. Preprint typeset in JHEP style - HYPER VERSION SU-ITP-10-18 OUTP-10-10P Axion-Assisted Electroweak Baryogenesis Nathaniel Craig Institute for Theoretical Physics, Stanford University, Stanford, CA 94306, USA E-mail: ncraig@stanford.edu ...

Yuri Golfand Memorial Volume, 2000

Page 1. arXiv:hep-th/9908146v1 21 Aug 1999 CERN-TH-99-219 SU-ITP-99/38 LBNL-44031 Logarithmic Uni... more Page 1. arXiv:hep-th/9908146v1 21 Aug 1999 CERN-TH-99-219 SU-ITP-99/38 LBNL-44031 Logarithmic Unification From Symmetries Enhanced in the Sub-Millimeter Infrared ∗ Nima Arkani–Hamed ∗∗ , Savas ...

Physical Review D, 2007

ABSTRACT We study the predictions of holographic QCD for various observable four-point quark flav... more ABSTRACT We study the predictions of holographic QCD for various observable four-point quark flavour current-current correlators. The dual 5-dimensional bulk theory we consider is a SU(3)LtimesSU(3)RSU(3)_L \times SU(3)_RSU(3)LtimesSU(3)R Yang Mills theory in a slice of AdS5AdS_5AdS5 spacetime with boundaries. Particular UV and IR boundary conditions encode the spontaneous breaking of the dual 4D global chiral symmetry down to the SU(3)VSU(3)_VSU(3)V subgroup. We explain in detail how to calculate the 4D four-point quark flavour current-current correlators using the 5D holographic theory, including interactions. We use these results to investigate predictions of holographic QCD for the DeltaI=1/2\Delta I = 1/2DeltaI=1/2 rule for kaon decays and the BKB_KBK parameter. The results agree well in comparison with experimental data, with an accuracy of 25% or better. The holographic theory automatically includes the contributions of the meson resonances to the four-point correlators. The correlators agree well in the low-momentum and high-momentum limit, in comparison with chiral perturbation theory and perturbative QCD results, respectively.