papers

Publications (101)

hep-th2020

QCD, Flavor, and the de Sitter Swampland

John March-Russell, Rudin Petrossian-Byrne

The refined swampland de Sitter conjecture (SdSC) is a proposed constraint on the form of the total potential in a theory including quantum gravity. According to this conjecture po…

hep-ph2026

A more effective QCD string at colliders: Decay of excited strings and the worldsheet axion

Ethan Carragher, John March-Russell

The confining flux tube of d QCD is described by an effective string theory with d worldsheet action that extends the Nambu-Goto form by the addition of a massive pse…

hep-ph2006

On the Delta I = 1/2 Rule in Holographic QCD

Thomas Hambye, Babiker Hassanain, John March-Russell +1

We study the rule for kaon decays and the parameter for mixing in a dual 5-dimensional holographic QCD model. We perform, in the chiral limit,…

hep-ph1992

On the Possibility of Second-Order Phase Transitions in Spontaneously Broken Gauge Theories

John March-Russell

In the ``Type-II'' regime, $m_{\rm Higgs}\gap m_{\rm gauge}$, the finite-temperature phase transition in spontaneously-broken gauge theories (including the standard model) must be…

hep-ph1996

Leptophobic U(1)'s and the R_b - R_c Crisis

K. S. Babu, Chris Kolda, John March-Russell

In this paper, we investigate the possibility of explaining both the R_b excess and the R_c deficit reported by the LEP experiments through Z-Z' mixing effects. We have constructed…

hep-th1997

Realizing Higher-Level Gauge Symmetries in String Theory: New Embeddings for String GUTs

Keith R. Dienes, John March-Russell

We consider the methods by which higher-level and non-simply laced gauge symmetries can be realized in free-field heterotic string theory. We show that all such realizations have a…

hep-ph2000

Compact Hyperbolic Extra Dimensions: Branes, Kaluza-Klein Modes and Cosmology

Nemanja Kaloper, John March-Russell, Glenn D. Starkman +1

We reconsider theories with low gravitational (or string) scale M_* where Newton's constant is generated via new large-volume spatial dimensions, while Standard Model states are lo…

astro-ph.CO2020

Reproductive Freeze-In of Self-Interacting Dark Matter

John March-Russell, Hannah Tillim, Stephen M. West

We present a mechanism for dark matter (DM) production involving a self-interacting sector that at early times is ultra-relativistic but far-underpopulated relative to thermal equi…

hep-th2001

Saltatory Relaxation of the Cosmological Constant

Jonathan L. Feng, John March-Russell, Savdeep Sethi +1

We modify and extend an earlier proposal by Brown and Teitelboim to relax the effective cosmological term by nucleation of branes coupled to a three-index gauge potential. Microsco…

hep-ph2012

Closing in on Asymmetric Dark Matter I: Model independent limits for interactions with quarks

John March-Russell, James Unwin, Stephen M. West

It is argued that experimental constraints on theories of asymmetric dark matter (ADM) almost certainly require that the DM be part of a richer hidden sector of interacting states…

hep-ph1998

CP Violation, Higgs Couplings, and Supersymmetry

K. S. Babu, Christopher Kolda, John March-Russell +1

Supersymmetric extensions of the standard model generically contain additional sources of CP violation. We discuss how at one loop a potentially large CP violating coupling of the…

hep-ph1998

Neutrino Masses from Large Extra Dimensions

Nima Arkani-Hamed, Savas Dimopoulos, Gia Dvali +1

Recently it was proposed that the standard model (SM) degrees of freedom reside on a -dimensional wall or ``3-brane'' embedded in a higher-dimensional spacetime. Furthermore…

hep-ph2008

Heavy Dark Matter Through the Higgs Portal

John March-Russell, Stephen M. West, Daniel Cumberbatch +1

Motivated by Higgs Portal and Hidden Valley models, heavy particle dark matter that communicates with the supersymmetric Standard Model via pure Higgs sector interactions is consid…

hep-ph2003

Calculable Corrections to Brane Black Hole Decay II: Greybody Factors for Spin 1/2 and 1

Panagiota Kanti, John March-Russell

The production of black holes in extra-dimensional brane-world theories can lead to detectable signals via the Hawking evaporation of the black hole to brane-localised Standard Mod…

hep-th1995

String Unification, Higher-Level Gauge Symmetries, and Exotic Hypercharge Normalizations

Keith R. Dienes, Alon E. Faraggi, John March-Russell

We explore the extent to which string theories with higher-level gauge symmetries and non-standard hypercharge normalizations can reconcile the discrepancy between the string unifi…

hep-ph2024

Chern-Simons Induced Thermal Friction on Axion Domain Walls

Saquib Hassan, Gaurang Ramakant Kane, John March-Russell +1

We study the dynamics and interactions of the solitonic domain walls that occur in realistic axion electrodynamics models including the Chern-Simons interaction, $aε_{μνλσ}F^{…

hep-ph2010

The Goldstini Variations

Nathaniel Craig, John March-Russell, Matthew McCullough

We study the 'goldstini' scenario of Cheung, Nomura, and Thaler, in which multiple independent supersymmetry (SUSY) breaking sectors lead to multiple would-be goldstinos, changing…

hep-ph2017

Higgs Assisted Q-balls from Pseudo-Nambu-Goldstone Bosons

Fady Bishara, George Johnson, Olivier Lennon +1

Motivated by recent constructions of TeV-scale strongly-coupled dynamics, either associated with the Higgs sector itself as in pseudo-Nambu-Goldstone boson (pNGB) Higgs models or i…

hep-ph2009

Neutrino-Flavoured Sneutrino Dark Matter

John March-Russell, Christopher McCabe, Matthew McCullough

A simple theory of supersymmetric dark matter (DM) naturally linked to neutrino flavour physics is studied. The DM sector comprises a spectrum of mixed lhd-rhd sneutrino states whe…

hep-ph1997

Implications of Generalized Z-Z' Mixing

K. S. Babu, Christopher Kolda, John March-Russell

We discuss experimental implications of extending the gauge structure of the Standard Model to include an additional U(1) interaction broken at or near the weak scale. We work with…

hep-ph2016

Baryogenesis via Particle-Antiparticle Oscillations

Seyda Ipek, John March-Russell

CP violation, which is crucial for producing the baryon asymmetry of the Universe, is enhanced in particle-antiparticle oscillations. We study particle-antiparticle oscillations (o…

astro-ph.CO2020

Hot Gravitons and Gravitational Waves From Kerr Black Holes in the Early Universe

Dan Hooper, Gordan Krnjaic, John March-Russell +2

Any abundance of black holes that was present in the early universe will evolve as matter, making up an increasingly large fraction of the total energy density as space expands. Th…

hep-ph1995

New Symmetries of Supersymmetric Effective Lagrangians

Markus A. Luty, John March-Russell, Hitoshi Murayama

We consider the structure of effective lagrangians describing the low-energy dynamics of supersymmetric theories in which a global symmetry is spontaneously broken to a subgrou…

hep-ph2015

Rare Flavor Processes in Maximally Natural Supersymmetry

Isabel García García, John March-Russell

We study CP-conserving rare flavor violating processes in the recently proposed theory of Maximally Natural Supersymmetry (MNSUSY). MNSUSY is an unusual supersymmetric (SUSY) exten…

hep-ph2010

A Unified Theory of Matter Genesis: Asymmetric Freeze-In

Lawrence J. Hall, John March-Russell, Stephen M. West

We propose a unified theory of dark matter (DM) genesis and baryogenesis. It explains the observed link between the DM density and the baryon density, and is fully testable by a co…

hep-th1991

Quantum Field Theory of Nonabelian Strings and Vortices

Mark Alford, Kai-Ming Lee, John March-Russell +1

We develop an operator formalism for investigating the properties of nonabelian cosmic strings (and vortices) in quantum field theory. Operators are constructed that introduce clas…

hep-ph2002

The Flavour Hierarchy and See-Saw Neutrinos from Bulk Masses in 5d Orbifold GUTs

Arthur Hebecker, John March-Russell

In supersymmetric grand unified theories (GUTs) based on S^1/(Z_2 x Z'_2) orbifold constructions in 5 dimensions, Standard Model (SM) matter and Higgs fields can be realized in ter…

hep-th2002

Depilating Global Charge From Thermal Black Holes

John March-Russell, Frank Wilczek

At a formal level, there appears to be no difficulty involved in introducing a chemical potential for a globally conserved quantum number into the partition function for space-time…

hep-ph2002

Calculable Corrections to Brane Black Hole Decay I: The Scalar Case

Panagiota Kanti, John March-Russell

In the context of brane-world theories, the production cross-section for black holes may be greatly enhanced. Such black holes can in principle lead to detectable signals via their…

hep-ph1997

Kinetic Mixing and the Supersymmetric Gauge Hierarchy

Keith R. Dienes, Christopher Kolda, John March-Russell

The most general Lagrangian for a model with two U(1) gauge symmetries contains a renormalizable operator which mixes their gauge kinetic terms. Such kinetic mixing can be generate…

hep-th2018

Hawking Radiation of Extended Objects

George Johnson, John March-Russell

We compute the effects on the temperature and precise spectrum of Hawking radiation from a Schwarzschild black hole when the emitted object is taken to be spatially extended. We fi…

hep-ph2026

Prediction for Maximum Supercooling in SU(N) Confinement Transition

Prateek Agrawal, Gaurang Ramakant Kane, Vazha Loladze +1

The thermal confinement phase transition (PT) in Yang-Mills theory is first-order for , with bounce action scaling as . Remarkably, lattice data for the actio…

hep-ph2001

Towards a Theory of Flavor from Orbifold GUTs

Lawrence Hall, John March-Russell, Takemichi Okui +1

We show that the recently constructed 5-dimensional supersymmetric orbifold GUT models allow an appealing explanation of the observed hierarchical structure…

hep-ph2000

Classical and Quantum Brane Cosmology

John March-Russell

The first part of this lecture quickly touches upon some important but infrequently discussed issues in large extra dimension and warped extra dimension scenarios, with particular…

hep-ph2007

Four-point functions and kaon decays in a minimal AdS/QCD model

Thomas Hambye, Babiker Hassanain, John March-Russell +1

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)_…

hep-ph2004

A Simple Model of Neutrino Masses from Supersymmetry Breaking

John March-Russell, Stephen West

We analyze a class of supersymmetric models first introduced by Arkani-Hamed et al and Borzumati et al in which the light neutrino masses result from higher-dimensional supersymmet…

gr-qc2022

Micro-Bose/Proca dark matter stars from black hole superradiance

John March-Russell, João G. Rosa

We study the production of heavy, TeV, bosonic spin dark matter (DM) via the simultaneous processes of Hawking evaporation and superradiance (SR) from an init…

hep-ph1999

Rapid Asymmetric Inflation and Early Cosmology in Theories with Sub-Millimeter Dimensions

Nima Arkani-Hamed, Savas Dimopoulos, Nemanja Kaloper +1

It was recently pointed out that the fundamental Planck mass could be close to the TeV scale with the observed weakness of gravity at long distances being due the existence of new…

hep-th2009

String Axiverse

Asimina Arvanitaki, Savas Dimopoulos, Sergei Dubovsky +2

String theory suggests the simultaneous presence of many ultralight axions possibly populating each decade of mass down to the Hubble scale 10^-33eV. Conversely the presence of suc…

hep-ph2013

Axion Mediation

Masha Baryakhtar, Edward Hardy, John March-Russell

We explore the possibility that supersymmetry breaking is mediated to the Standard Model sector through the interactions of a generalized axion multiplet that gains a F-term expect…

hep-ph2014

Maximally Natural Supersymmetry

Savas Dimopoulos, Kiel Howe, John March-Russell

We consider 4D weak scale theories arising from 5D supersymmetric (SUSY) theories with maximal Scherk-Schwarz breaking at a Kaluza-Klein (KK) scale of several TeV. Many of the prob…

hep-th2020

Towards a Swampland Global Symmetry Conjecture using Weak Gravity

Tristan Daus, Arthur Hebecker, Sascha Leonhardt +1

It is widely believed and in part established that exact global symmetries are inconsistent with quantum gravity. One then expects that approximate global symmetries can be quantit…

hep-ph2011

On the DAMA and CoGeNT Modulations

Mads T. Frandsen, Felix Kahlhoefer, John March-Russell +3

DAMA observes an annual modulation in their event rate, as might be expected from dark matter scatterings, while CoGeNT has reported evidence for a similar modulation. The simplest…

hep-ph2026

Abundant production of scalars and axions from phase transition bubble expansion

Isabel Garcia Garcia, Gaurang Ramakant Kane, John March-Russell +1

We revisit aspects of particle production during cosmological first-order phase transitions, and show that the expansion of true-vacuum bubbles can be a copious source of particle…

hep-ph2015

Big Bang Synthesis of Nuclear Dark Matter

Edward Hardy, Robert Lasenby, John March-Russell +1

We investigate the physics of dark matter models featuring composite bound states carrying a large conserved dark "nucleon" number. The properties of sufficiently large dark nuclei…

astro-ph.CO2021

Evaporating primordial black holes, the string axiverse, and hot dark radiation

Marco CalzÃ, John March-Russell, João G. Rosa

We show that primordial black holes (PBHs) develop non-negligible spins through Hawking emission of the large number of axion-like particles generically present in string theory co…

hep-ph1998

Supersymmetric D-term Inflation, Reheating and Affleck-Dine Baryogenesis

Christopher Kolda, John March-Russell

The phenomenology of supersymmetric models of inflation, where the inflationary vacuum energy is dominated by D-terms of a U(1), is investigated. Particular attention is paid to th…

hep-ph1993

Radiatively-Induced First-Order Phase Transitions: The Necessity of the Renormalization Group

Mark Alford, John March-Russell

We advocate a (Wilson) renormalization-group (RG) treatment of finite-temperature first-order phase transitions, in particular those driven by radiative corrections such as occur i…

hep-th2007

Warped Deformed Throats have Faster (Electroweak) Phase Transitions

Babiker Hassanain, John March-Russell, Martin Schvellinger

We study the dynamics of the finite-temperature phase transition for warped Randall-Sundrum(RS)-like throat models related to the Klebanov-Tseytlin solution. We find that, for infr…

physics.ins-det2023

Long nanomechanical resonators with circular cross-section

Samuli Autti, Andrew Casey, Marie Connelly +23

Fabrication of superconducting nanomechanical resonators for quantum research, detectors and devices traditionally relies on a lithographic process, resulting in oscillators with s…

hep-ph1997

Building Models Of Gauge Mediated Supersymmetry Breaking Without A Messenger Sector

Nima Arkani-Hamed, John March-Russell, Hitoshi Murayama

We propose a general scheme for constructing models in which the Standard Model (SM) gauge interactions are the mediators of supersymmetry breaking to the fields in the supersymmet…

hep-ph2009

String Photini at the LHC

Asimina Arvanitaki, Nathaniel Craig, Savas Dimopoulos +2

String theories with topologically complex compactification manifolds suggest the simultaneous presence of many unbroken U(1)'s without any light matter charged under them. The gau…

hep-th2024

Chern-Simons bubbles: Lopsided false vacuum decay in axion electrodynamics

Saquib Hassan, John March-Russell, Georges Obied

We study axion electrodynamics, including the Chern-Simons interaction term, in the presence of parallel background electric and magnetic fields, as can for example occur in certai…

hep-th1999

Logarithmic Unification From Symmetries Enhanced in the Sub-Millimeter Infrared

Nima Arkani-Hamed, Savas Dimopoulos, John March-Russell

In theories with TeV string scale and sub-millimeter extra dimensions the attractive picture of logarithmic gauge coupling unification at GeV is seemingly destroyed. In t…

hep-ph1998

The Fayet-Iliopoulos term in Type-I string theory and M-theory

John March-Russell

The magnitude of the Fayet-Iliopoulos term is calculated for compactifications of Type-I string theory and Horava-Witten M-theory in which there exists a pseudo-anomalous U(1)_X. C…

hep-th2021

Axiverse Strings

John March-Russell, Hannah Tillim

If the QCD axion solves the strong CP problem then light axion-like-particles (ALPs) are expected to be ubiquitous in string theory - the string axiverse. Such ALPs can be the QCD…

hep-ph2015

Natural Scherk-Schwarz Theories of the Weak Scale

Isabel Garcia Garcia, Kiel Howe, John March-Russell

Natural supersymmetric theories of the weak scale are under growing pressure given present LHC constraints, raising the question of whether untuned supersymmetric (SUSY) solutions…

astro-ph2010

WIMPonium and Boost Factors for Indirect Dark Matter Detection

John March-Russell, Stephen M. West

We argue that WIMP dark matter can annihilate via long-lived "WIMPonium" bound states in reasonable particle physics models of dark matter (DM). WIMPonium bound states can occur at…

hep-ph2004

TeV scale resonant leptogenesis from supersymmetry breaking

Thomas Hambye, John March-Russell, Stephen M. West

We propose a model of TeV-scale resonant leptogenesis based upon recent models of the generation of light neutrino masses from supersymmetry-breaking effects with TeV-scale right-h…

hep-ph2015

Signatures of Large Composite Dark Matter States

Edward Hardy, Robert Lasenby, John March-Russell +1

We investigate the interactions of large composite dark matter (DM) states with the Standard Model (SM) sector. Elastic scattering with SM nuclei can be coherently enhanced by fact…

hep-ph2004

Gauge Mediated Supersymmetry Breaking and Multi-TeV Gamma-Rays from the Galactic Center

Dan Hooper, John March-Russell

Recently, the HESS telescope has observed a gamma-ray spectrum from the galactic center extending to at least 10 TeV. Although it has been suggested that this could be the pr…

hep-ph1993

Baryons from Quarks in the Expansion

Markus A. Luty, John March-Russell

We present a diagrammatic analysis of baryons in the expansion, where is the number of QCD colors. We use this method to show that there are an infinite number of degener…

hep-ph2018

Black Hole Genesis of Dark Matter

Olivier Lennon, John March-Russell, Rudin Petrossian-Byrne +1

We present a purely gravitational infra-red-calculable production mechanism for dark matter (DM). The source of both the DM relic abundance and the hot Standard Model (SM) plasma i…

hep-th1992

Are Textures Natural?

Marc Kamionkowski, John March-Russell

We make the simple observation that, because of global symmetry violating higher-dimension operators expected to be induced by Planck-scale physics, textures are generically much t…

hep-ph2015

Twin Higgs WIMP Dark Matter

Isabel García García, Robert Lasenby, John March-Russell

Dark matter (DM) without a matter asymmetry is studied in the context of Twin Higgs (TH) theories in which the LHC naturalness problem is addressed. These possess a twin sector rel…

hep-ph2015

Twin Higgs Asymmetric Dark Matter

Isabel García García, Robert Lasenby, John March-Russell

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)' \times S…

hep-ph2002

The Structure of GUT Breaking by Orbifolding

Arthur Hebecker, John March-Russell

Recently, an attractive model of GUT breaking has been proposed in which a 5 dimensional supersymmetric SU(5) gauge theory on an S^1/(Z_2\times Z_2') orbifold is broken down to the…

hep-ph2002

Proton Decay Signatures of Orbifold GUTs

Arthur Hebecker, John March-Russell

In grand unified theories based on orbifold constructions in higher dimensions, Higgsino-mediated proton decay is absent. However, proton decay mediated by and gauge bosons…

astro-ph2009

Inelastic Dark Matter, Non-Standard Halos and the DAMA/LIBRA Results

John March-Russell, Christopher McCabe, Matthew McCullough

The DAMA collaboration have claimed to detect particle dark matter (DM) via an annual modulation in their observed recoil event rate. This appears to be in strong disagreement with…

hep-ph2005

Pseudo-Goldstones from Supersymmetric Wilson Lines on 5D Orbifolds

Thomas Flacke, Babiker Hassanain, John March-Russell

We consider a U(1) gauge theory on the five dimensional orbifold , where has even parity. This leads to a light pseudoscalar degree of free…

hep-th2026

Compact space catalysis of false vacuum decay and Schwinger effect

Saquib Hassan, John March-Russell

We study zero-temperature false vacuum decay in compact spatial dimensions and show that for volumes below a critical value a new bounce solution, different from Coleman's cele…

hep-ph2011

Asymmetric Dark Matter via Spontaneous Co-Genesis

John March-Russell, Matthew McCullough

We investigate, in the context of asymmetric dark matter (DM), a new mechanism of spontaneous co-genesis of linked DM and baryon asymmetries, explaining the observed relation betwe…

hep-ph1997

Comments on the high- HERA anomaly

K. S. Babu, Christopher Kolda, John March-Russell +1

Taking the reported high-Q^2 anomaly at HERA as a signal of new physics, we show that several independent considerations point towards s-channel leptoquark production as the most a…

hep-th1992

Planck-Scale Physics and the Peccei-Quinn Mechanism

Marc Kamionkowski, John March-Russell

Global-symmetry violating higher-dimension operators, expected to be induced by Planck-scale physics, in general drastically alter the properties of the axion field associated with…

hep-ph2009

Freeze-In Production of FIMP Dark Matter

Lawrence J. Hall, Karsten Jedamzik, John March-Russell +1

We propose an alternate, calculable mechanism of dark matter genesis, "thermal freeze-in," involving a Feebly Interacting Massive Particle (FIMP) interacting so feebly with the the…

hep-ph2022

Dark Photon Stars: Formation and Role as Dark Matter Substructure

Marco Gorghetto, Edward Hardy, John March-Russell +2

Any new vector boson with non-zero mass (a `dark photon' or `Proca boson') that is present during inflation is automatically produced at this time from vacuum fluctuations and can…

physics.atom-ph2021

Matter-wave Atomic Gradiometer Interferometric Sensor (MAGIS-100)

Mahiro Abe, Philip Adamson, Marcel Borcean +45

MAGIS-100 is a next-generation quantum sensor under construction at Fermilab that aims to explore fundamental physics with atom interferometry over a 100-meter baseline. This novel…

hep-ph1997

Modified parton distributions and the HERA high-Q^2 anomaly

K. S. Babu, Christopher Kolda, John March-Russell

A recent proposal seeks to explain the anomaly in the HERA high-Q^2 neutral current e^+p data by modifying the parton distribution functions at moderate-to-high-x and large Q^2. We…

hep-ph2013

Retrofitted Natural Supersymmetry from a U(1)

Edward Hardy, John March-Russell

We propose that a single, spontaneously broken, U(1) gauge symmetry may be responsible for suppressing both the first two generation Yukawa couplings, and also, in a correlated man…

hep-ph2005

Improved Bounds on Universal Extra Dimensions and Consequences for LKP Dark Matter

Thomas Flacke, Dan Hooper, John March-Russell

We study constraints on models with a flat "Universal'' Extra Dimension in which all Standard Model fields propagate in the bulk. A significantly improved constraint on the compact…

hep-ph2004

Asymmetric Sneutrino Dark Matter and the Omega(b)/Omega(DM) Puzzle

Dan Hooper, John March-Russell, Stephen M. West

The inferred values of the cosmological baryon and dark matter densities are strikingly similar, but in most theories of the early universe there is no true explanation of this fac…

hep-th1998

Black Holes and Sub-millimeter Dimensions

Philip C. Argyres, Savas Dimopoulos, John March-Russell

Recently, a new framework for solving the hierarchy problem was proposed which does not rely on low energy supersymmetry or technicolor. The fundamental Planck mass is at a TeV and…

hep-ph2012

Precision Unification in λSUSY with a 125 GeV Higgs

Edward Hardy, John March-Russell, James Unwin

It is challenging to explain the tentative 125 GeV Higgs signal in the Minimal Supersymmetric Standard Model (MSSM) without introducing excessive fine-tuning, and this motivates th…

hep-th1991

Internal Frame Dragging and a Global Analog of the Aharonov-Bohm Effect

John March-Russell, John Preskill, Frank Wilczek

It is shown that the breakdown of a {\it global} symmetry group to a discrete subgroup can lead to analogues of the Aharonov-Bohm effect. At sufficiently low momentum, the cross-se…

hep-ph1996

Low-Energy Signatures of Semi-perturbative Unification

Christopher Kolda, John March-Russell

We consider the low-energy signatures of, and high-energy motivations for, scenarios of semi-perturbative gauge coupling unification. Such scenarios can leave striking imprints on…

hep-ph2016

The String Soundscape at Gravitational Wave Detectors

Isabel Garcia Garcia, Sven Krippendorf, John March-Russell

We argue that gravitational wave (GW) signals due to collisions of ultra-relativistic bubble walls may be common in string theory. This occurs due to a process of post-inflationary…

hep-ph2016

Unified Maximally Natural Supersymmetry

Junwu Huang, John March-Russell

Maximally Natural Supersymmetry, an unusual weak-scale supersymmetric extension of the Standard Model based upon the inherently higher-dimensional mechanism of Scherk-Schwarz super…

hep-th1998

Stabilization of Sub-Millimeter Dimensions: The New Guise of the Hierarchy Problem

Nima Arkani-Hamed, Savas Dimopoulos, John March-Russell

A new framework for solving the hierarchy problem was recently proposed which does not rely on low energy supersymmetry or technicolor. The fundamental Planck mass is at a $\tev$ a…

hep-ph2009

Inducing the mu and the B mu Term by the Radion and the 5d Chern-Simons Term

Arthur Hebecker, John March-Russell, Robert Ziegler

In 5-dimensional models with gauge-Higgs unification, the F-term vacuum expectation value of the radion provides, in close analogy to the Giudice-Masiero mechanism, a natural sourc…

hep-th2025

De Sitter space constraints on brane tensions and couplings

Saquib Hassan, Georges Obied, John March-Russell

We argue for the existence of bounds on the tensions of -branes in de Sitter space in terms of the Hubble rate and the strength of a class of Chern-Simons-like couplings. The wo…

astro-ph2006

Signals of Inflation in a Friendly String Landscape

John March-Russell, Francesco Riva

Following Freivogel {\it et al} we consider inflation in a predictive (or `friendly') region of the landscape of string vacua, as modeled by Arkani-Hamed, Dimopoulos and Kachru. In…

hep-ph2015

Auto-Concealment of Supersymmetry in Extra Dimensions

Savas Dimopoulos, Kiel Howe, John March-Russell +1

In supersymmetric (SUSY) theories with extra dimensions the visible energy in sparticle decays can be significantly reduced and its energy distribution broadened, thus significantl…

hep-ph1994

Baryon Magnetic Moments in a Simultaneous Expansion in and

Markus A. Luty, John March-Russell, Martin White

We consider the baryon octet and decuplet magnetic moments in a simultaneous expansion in and taking , where is the number of QCD colors and i…

hep-ph2006

Warped Axions

Thomas Flacke, Ben Gripaios, John March-Russell +1

We study a number of realizations of axions existing in a multi-`throat' generalization of the warped throat geometry of a Randall-Sundrum slice of . As argued by previous a…

hep-ph1999

Early Inflation and Cosmology in Theories with Sub-Millimeter Dimensions

Nima Arkani-Hamed, Savas Dimopoulos, Nemanja Kaloper +1

We discuss early cosmology in theories where the fundamental Planck mass is close to the TeV scale. In such theories the standard model fields are localized to a (3+1)-dimensional…

hep-ph1997

Implications of a charged-current anomaly at HERA

K. S. Babu, Christopher Kolda, John March-Russell

We demonstrate that in the presence of mixing between different scalar leptoquark multiplets it is possible to simultaneously account for the HERA high- neutral current anomal…

astro-ph.IM2022

Cold Atoms in Space: Community Workshop Summary and Proposed Road-Map

Ivan Alonso, Cristiano Alpigiani, Brett Altschul +246

We summarize the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportu…

hep-ph2010

Axion-Assisted Electroweak Baryogenesis

Nathaniel Craig, John March-Russell

We consider a hidden-valley gauge sector, G, with strong coupling scale Lambda~TeV and CP-violating topological parameter, theta, as well as a new axion degree of freedom which adj…

hep-ph2009

On the possibility of light string resonances at the LHC and Tevatron from Randall-Sundrum throats

Babiker Hassanain, John March-Russell, J. G. Rosa

In string realizations of the Randall-Sundrum scenario, the higher-spin Regge excitations of Standard Model states localized near the IR brane are warped down to close to the TeV s…

hep-th2008

Resonant particle production in branonium

J. G. Rosa, John March-Russell

We study the mechanism of particle production in the world-volume of a probe anti D6-brane (or D6 with SUSY breaking) moving in the background created by a fixed stack of -bran…