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Jan Masters, Jonathan Northcroft, Waldemar Januszczak, John Dugdale, Barbara Hall, Lucas Hollweg, Jerry Wood, Michael O'Hare, Michael Harwood, Helen Davies, Felice Hardy, Peter Whittle, Sally Brock, Jane Jones, Rob Hughes, John Peter, Pam Barrett, Professor Gideon Garter, Amanda Ursell, Jonathan Miller, Tim Dawson, Jim Munro football editor, Andrew Longmore, Jane Mulkerrins, Christopher Somerville, Liz Hancock, Susan d'Arcy, Ian Blackshaw, Peter Day, Gareth Walsh, Frank Whitford, Heather Rigby, Ivo Tennant, Nicolette Jones, Ferdinand Mount, Matt Wolf, Kathryn Cooper, Harriet Sergeant, P D, David Smith, Nick Oswald, Richard Bond, Britan Dougan, Steven Poole, David Cracknell Political Editor, Nick Pitt, Emily Edmonstone, Neil Wormald, E P, Sir Michael Salt, Andrew Sullivan, Clive Davis, Gary Le Strange, Stephen Grey, Andrew Farquhar, Robert Holland, Andrew Porter, Chris Morgan, Catherine Moye, Kathy Brewis, Tony Allen-Mills, Simon Wilde, Dr Alfred Lake, Martin James, P J McVean, Tom Walker, Anthony Piercy, Robert Winnett, Ben Ainslie, Dipesh Gadher Transport Correspondent, Ben Heywood, Martin Bashir Celebrity interviewer, Tom English, Steve Walsham, Peter Wilson, Hugh Ball, Irwin Stelzer, Rachel Doni, Lawrence Dallaglio, Geoff Hill, Adrian Furnham, Paul Marfleet, Rosie Millard, David Dougill, Jill Darcy, Rhianna Pratchett, Stephen Taylor, Philip Kingsley, Alan Rhodes, Paul Flynn, David Hewson, Dozen, Alistair Weaver, Ivor Guiney, David Bond, Robert Hewison, Jonathon Carr-Brown, Alasdair Reid, Rivka Goldschmidt, Margarette Driscoll, Hugh Canning, Jeremy Clarkson, Andrew Stone, San Blas Bay, Edward Porter, Ian Botham, David Cairns, Veronica Coulson, Stewart Lee, Victoria Segal, Fergus Garrett, Sarah Dempster, Euros Walters, Hans Wegner, Kevin Jackson, John O'Donnell, Peter Millar, Simon Rogerson, Shelley von Strunckel, Afsaneh Khalat-Bari, Giles Milton, Jeremy Guscott, Sir Richard Branson, Paula Robinson, Jill Douglas, Richard Johnson, Roy Strong, Roger Eglin, Paul Donovan, Peter Hounam, Anthony Rogers, Paul Kimmage, Colin Terry, Chris Woodhead, Steve Boyd, Lucinda Kemeny, Jasper Gerard, Derek Clements, Paul Driver, John Humphrys, Chris West, Nicholas Hellen, Richard Brooks, John Norman, Julie Earle-Levine, Ian Hawkey, Sally Jones, Tony Spear, Alex Clark, David Leppard, Paul Durman, Alicia Wyllie, Mark Edwards, Rachel Bridge, Susan Clark, Stephen Amidon, Eben Black Chief Political Correspondent, David Miller, Susan Greenfield, Professor S Bush, Tony Sewell, Alan Combes, Frank Warburton, Michael O'Leary, C L, Raymond Keene, Gareth Huw Davies, Douglas Brinkley, Dominic Lutyens, David Cracknell, Cosmo Landesman, Katrina Manson, Zoe Brennan, Jacqueline Linning, C Bowker, Ted Smart, Jim Irvin, Martin O'Neill Celtic manager, Catherine Turner, Stephen Jones, Dominic O'Connell, Stephen Bleach, Barry Flatman, Uzi Mahnaimi, Nick Cain, Louise Armitstead, Michael Wright, Melinda Stevens, Jean Morgan, Natalie Graham, Rosie Brown, Caroline Donald, Beatrice Newbery, Nick Rennison, Caroline Gascoigne, Liat Joshi, Sophie Tweedale, Jack Grimston, Francesca Anslow, Bryan Appleyard, Andrew White, Colin Davidson, Soheir Khashoggi, Earl Howe, John Elliott, Marty Wilde, John Waller, Stephen Armstrong, Mark Anstead, Swan Lake, Bethan Cole, R W Johnson, Jonathan Leake Environment Editor, Victoria O'brien, Richard Woods, Roland White, Maurice Chittenden, Richard Brooks Arts Editor, Yuba Bessaoud, Joseph Feld, Judith O'Reilly, Mark Franchetti, Richard Rae, Stuart Derrick, Jon Ungoed-Thomas, Ray Hutton, Jonathan Leake, Michael Sheridan, Ian Edwards, Amanda Craig, Clare Francis, Ian Thomson, David Sutherland, John Harlow, Margaret Walters, Dr Philip Welsby, Barry Collins, Claire James, Derrick Salmon, John Waples, Hunter Davies, Tony McCoy, Ros Dodd, A A Gill, Melanie McDonagh, Matthew Campbell, Des MacHale, Anssi Vanjoki, Mary Braid, Malcolm Goodson, Nick Fielding, Stephen Pettitt, Maria McErlane, Will Iredale, Claudia Croft, Justin Sparks, Sally Kinnes, Naomi Caine, Liam Clarke, David Wickers, B Butchinson, Phil Tufnell, Brian Doogan, Ben Dowell, Peter Schmeichel, John Aizlewood, Jeremy Lazell, Mark Hodson, Graham Norwood, Lois Rogers Medical Editor, Joe Lovejoy, Piers Pickard, David Budworth, William Lewis Business editor, Hugh Pearman, F H, Bob Murray, Pete Oliver, Paul Stephen Lubicz, Chrissie Hynde, Dan Cairns, Stewart Mitchell, Mrs Mills, David Smith Economics Editor, Minette Walters, Sarah Baxter, Colin McDowells, John Warburton-Lee, Chris Feetenby, Joanna Simon, David Robertson, Matthew Goodman, Kate Spicer, Stephen Applebaum, Simon Howard, Vikki Berg, Richard Lewis, Karen Robinson, Helen Stewart,

... Voice of Frank Sinatra Columbia/Legacy 507879-2 Franz Ferdinand Franz Ferdinand Domino WIGCD 136 Michel Petrucciani So What ...

2004 - Gale Group | Sunday Times HA GDA

Artigo Revisado por pares

Franz Wegner,

Tópico(s): Nonlinear Dynamics and Pattern Formation

1967 - Springer Science+Business Media | The European Physical Journal A

Artigo Revisado por pares

Eberhard K. Riedel, Franz Wegner,

Dynamic scaling laws for anisotropic magnetic systems are derived where the anisotropy parameters are explicitly treated. The approach is applied to calculate the critical spin relaxation rates for Heisenberg ferromagnets and antiferromagnets with one, two, and three easy axes of magnetization at $T>~{T}_{c}$.

Tópico(s): Physics of Superconductivity and Magnetism

1970 - American Physical Society | Physical Review Letters

Artigo Acesso aberto Revisado por pares

Eberhard K. Riedel, Franz Wegner,

used by UR (private communication from P. Slattery) .The value of & used is 0.006 (UR used 0

Tópico(s): Geomagnetism and Paleomagnetism Studies

1970 - American Physical Society | Physical Review Letters

Artigo Revisado por pares

Eberhard K. Riedel, Franz Wegner,

Tópico(s): Physics of Superconductivity and Magnetism

1970 - Elsevier BV | Physics Letters A

Artigo

Franz Wegner,

Tópico(s): Complex Systems and Time Series Analysis

1968 - Springer Nature | Zeitschrift für Physik A Hadrons and Nuclei

Artigo Revisado por pares

Eberhard K. Riedel, Franz Wegner,

Tópico(s): Geomagnetism and Paleomagnetism Studies

1969 - Springer Science+Business Media | The European Physical Journal A

Artigo

Franz Wegner,

Tópico(s): Magnetic properties of thin films

1969 - Springer Nature | Zeitschrift für Physik A Hadrons and Nuclei

Artigo

Leo P. Kadanoff, Franz Wegner,

The eight-vertex model solved by Baxter is shown to be equivalent to two Ising models with nearest-neighbor coupling interacting with one another via a four-spin coupling term. The critical properties of the model in the weak-coupling limit are in agreement with the scaling hypothesis. In this limit where $\ensuremath{\alpha}\ensuremath{\rightarrow}0$, the critical indices obey $\frac{\ensuremath{\gamma}}{{\ensuremath{\gamma}}_{0}}=\frac{\ensuremath{\beta}}{{\ensuremath{\beta}}_{0}}=\frac{\ensuremath{\ ...

Tópico(s): Algebraic structures and combinatorial models

1971 - American Physical Society | Physical review. B, Solid state

Artigo Revisado por pares

Franz Wegner,

It is shown that any Ising model with positive coupling constants is related to another Ising model by a duality transformation. We define a class of Ising models Mdn on d-dimensional lattices characterized by a number n = 1, 2, … , d (n = 1 corresponds to the Ising model with two-spin interaction). These models are related by two duality transformations. The models with 1 < n < d exhibit a phase transition without local order parameter. A nonanalyticity in the specific heat and a different qualitative ...

Tópico(s): Opinion Dynamics and Social Influence

1971 - American Institute of Physics | Journal of Mathematical Physics

Artigo

Franz Wegner,

Tópico(s): Quantum many-body systems

1972 - IOP Publishing | Journal of Physics C Solid State Physics

Artigo

Franz Wegner,

The effects of higher-order contributions to the linearized renormalization group equations in critical phenomena are discussed. This analysis leads to three quite different results: (i) An exact scaling law for redefined fields is obtained. These redefined fields are normally analytic functions of the physical fields. Corrections to the standard power laws are derived from this scaling law. (ii) The theory explains why logarithmic terms can exist in the free energy. (iii) The case in which the energy ...

Tópico(s): Statistical Mechanics and Entropy

1972 - American Physical Society | Physical review. B, Solid state

Artigo Revisado por pares

Eberhard K. Riedel, Franz Wegner,

The tricritical behavior of a classical three-well-potential model for two-component systems (such as ${\mathrm{He}}^{3}$-${\mathrm{He}}^{4}$ mixtures) is discussed by using renormalization-group techniques. The tricritical exponents and scaling fields are calculated for three dimensions.

Tópico(s): High-Energy Particle Collisions Research

1972 - American Physical Society | Physical Review Letters

Artigo

Franz Wegner,

Critical indices for isotropic systems of $n$-dimensional spins in ($d=4\ensuremath{-}\ensuremath{\epsilon}$)-dimensional lattices are calculated to order $\ensuremath{\epsilon}$. All critical indices corresponding to perturbations of the spin probability distribution are given. Such perturbations might arise from the effects of external or crystal fields on the spin system.

Tópico(s): Quantum and electron transport phenomena

1972 - American Physical Society | Physical review. B, Solid state

Artigo

Morgan K. Grover, Leo P. Kadanoff, Franz Wegner,

A recursion relation obtained by Wilson is used for the numerical calculation of critical indices for the $d=3$ classical Heisenberg model. Some of the results obtained are $\ensuremath{\gamma}=1.36$ and $\ensuremath{\varphi}=1.24$.

Tópico(s): Cosmology and Gravitation Theories

1972 - American Physical Society | Physical review. B, Solid state

Artigo

Franz Wegner,

Tópico(s): Material Dynamics and Properties

1976 - Springer Nature | Zeitschrift füur Physik B Condensed Matter

Artigo

Franz Wegner,

Using renormalization group arguments the author expands n-point correlation functions (for non-exceptional wavevectors) in expectation values of translational invariant short-range operators Oi. He uses the fact that the Fourier components of our operators become negligible for wavevectors q large in comparison to the momentum cut-off. The correlation functions show the same non-analyticities at the critical point as the expectation values (Oi). The expansion coefficients are regular in the thermodynamic ...

Tópico(s): Quantum, superfluid, helium dynamics

1975 - Institute of Physics | Journal of Physics A Mathematical and General

Artigo Revisado por pares

Franz Wegner,

Critical exponents for nontrivial fixed points of order σ branching off from the trivial fixed point at dimensionality dσ = 2σ(σ−1) and the exponent η are reported in order ϵ and ϵ2, respectively.

Tópico(s): Material Dynamics and Properties

1975 - Elsevier BV | Physics Letters A

Artigo

Eberhard K. Riedel, Franz Wegner,

A semi-microscopic scaling-field theory is developed for crossover phenomena near critical and tricritical points. The theory is based on a renormalization-group description of a model with two competing fixed points (such as a critical and a tricritical fixed point) in terms of scaling fields. The coupled nonlinear differential equations for scaling fields are truncated such as to preserve the physics essential for crossover phenomena. The approach allows the explicit calculation of thermodynamic ...

Tópico(s): Spectroscopy and Quantum Chemical Studies

1974 - American Physical Society | Physical review. B, Solid state

Artigo

Franz Wegner,

A generalization of Wilson's renormalization group equation is discussed. A large class of equivalent fixed points exists for each fixed point. The eigen perturbations fall into two classes: (i) scaling operators whose scaling exponents are independent of the fixed point within the class of equivalent fixed points, and (ii) redundant operators whose exponents depend on the choice of the renormalization group equation. The exponents of the redundant operators are spurious since the free energy depends ...

Tópico(s): Solid-state spectroscopy and crystallography

1974 - IOP Publishing | Journal of Physics C Solid State Physics

Artigo

A. Houghton, Franz Wegner,

It is shown that the critical indices corresponding to (0, $l$ perturbations can be calculated by a Feynman-diagram method. At order ${\ensuremath{\epsilon}}^{2}$, the results are consistent with the special cases $l=1,2, \mathrm{and} 4$ obtained previously. There is also general agreement to order $\ensuremath{\epsilon}$ with the exponents calculated from Wilson's recurrence relation.

Tópico(s): Quantum, superfluid, helium dynamics

1974 - American Institute of Physics | Physical review. A, General physics

Artigo

Franz Wegner,

The elimination of the elastic degrees of freedom of a harmonic isotropic lattice transforms the magnetoelastic coupling into an effective magnetic interaction which consists of a short-range interaction recently discussed by Aharony and a long-range interaction due to the free surface of the systems. Within the renormalization group approach to critical phenomena it is shown that the critical behaviour of the system is described appropriately by the magnetothermomechanics provided that the additional ...

Tópico(s): Material Dynamics and Properties

1974 - IOP Publishing | Journal of Physics C Solid State Physics

Artigo Revisado por pares

Franz Wegner,

The behaviour of a quantum mechanic particle moving in a random potential is considered with special emphasis on the aspect of local gauge-invariance. Symmetry arguments are reviewed which allow the mapping of such a system onto a field theoretic model of interacting matrices. This model yields an expansion of the critical exponents at the mobility edge around the lower critical dimensionality two.

Tópico(s): Theoretical and Computational Physics

1980 - Elsevier BV | Physics Reports

Artigo

A. Houghton, Lothar Schäfer, Franz Wegner,

We use a variational approach to calculate the two-particle spectral function ${S}_{2}({x}_{1}, {x}_{1}, {x}_{2}, {x}_{2}, {E}_{1}{E}_{2})$ of a Gaussian-disordered electron system in the limit of deeply localized states and small energy difference $\ensuremath{\omega}={E}_{1}\ensuremath{-}{E}_{2}$. The solution of the variational equations yields a two-center potential, each center in lowest order being determined by the square of an instanton function. The two instantons interact via the constraint that ...

Tópico(s): Theoretical and Computational Physics

1980 - American Physical Society | Physical review. B, Condensed matter

Artigo Revisado por pares

Dirk Reinhardt, Michael G. Nagel, E. A. Stemmann, Franz Wegner,

Tópico(s): Asthma and respiratory diseases

1980 - Springer Science+Business Media | European Journal of Pediatrics

Artigo

Lothar Schäfer, Franz Wegner,

Tópico(s): Quantum many-body systems

1980 - Springer Nature | Zeitschrift füur Physik B Condensed Matter

Artigo

Franz Wegner,

Tópico(s): Cold Atom Physics and Bose-Einstein Condensates

1980 - Springer Nature | Zeitschrift füur Physik B Condensed Matter

Artigo

Franz Wegner, Anthony Houghton,

An exact renormalization equation is derived by making an infinitesimal change in the cutoff in momentum space. From this equation the expansion for critical exponents around dimensionality 4 and the limit $n=\ensuremath{\infty}$ of the $n$-vector model are calculated. We obtain agreement with the results of Wilson and Fisher, and with the spherical model.

Tópico(s): Quantum chaos and dynamical systems

1973 - American Institute of Physics | Physical review. A, General physics

Artigo

Franz Wegner,

Tópico(s): Algebraic structures and combinatorial models

1973 - Elsevier BV | Physica

Artigo Revisado por pares

Franz Wegner,

The magnetic phase diagram of mixed crystals of type (Mn, Fe)WO4 is discusses within molecular field approximation. The two species of magnetic ions tend to align in different orderings. Depending on the interaction strengths the two ordered phases are separated either by a phase in which both orderings are superimposed or by a first order transition. Das magnetische Phasendiagram von Mischkristallen des Typs (Mn, Fe)WO4 wird im Rahen der Molekularfeldnäherung diskutiert. Die zwei Arten magnetischer ...

Tópico(s): Metallurgical Processes and Thermodynamics

1973 - Elsevier BV | Solid State Communications