Homepage of Jeppe Dyre.

Professor of physics at IMFUFA, Department of Sciences, Roskilde University.

Director of the research group Glass and Time
Member of the Royal Danish Academy of Sciences and Letters

                                                                                                                                                                                                            




Address:

    DNRF Centre of Viscous Liquid Dynamics Glass and Time,  
    IMFUFA
, Building 27,
    Roskilde University,
    Postbox 260,
    DK-4000 Roskilde,
    Denmark.

Telephone:
                    Mobile:                        Fax:                               E-mail:
    (+45) 46 74 22 84          (+45) 30 25 85 07         (+45) 46 74 30 20           dyre@ruc.dk                                               



Research interests:


I. Viscous liquids and the glass transition
    Collaborating with Thomas Schrøder, Tage Christensen, and Niels Boye Olsen - as well as with several talented postdocs, Ph.D., and master's degree students throughout the years - we focus on trying to answer the basic questions:
     --    We have developed a simple model for the non-Arrhenius behavior - the 'shoving' model - according to which the energy needed for molecular rearrangements is mainly the shear elastic energy associated with creating extra space (1996, 1998, 2004, 2006, 2012).
  
  --    We have found that, once interference from the beta process is insignificant, the high-frequency exponent of the alpha process seems to be always -1/2 (2001, 2007). One possible explanation is that this is caused by a negative long-time tail (2005).
   
--    We have proposed a phenomenological model for beta relaxation, assuming structure is described by just one order parameter (2003).
    --    We have shown that in many cases a single-parameter description works quite well (2006, 2007, 2008).
    --    We have studied strong pressure-energy correlations in the equilibrium fluctuations of model liquids and their consequences for viscous liquid dynamics (2007-2012).
    --    We have proposed the new concept in statistical mechanics "isomorphs" in a system's phase diagram and shown that a liquid or solid has good isomorphs if and only if it has strong virial potential-energy correlations (2009-2012).
    --    The isomorph theory gives rise to a new molecular dynamics, "NVU dynamics", which consists of geodesic motion on the constant-potential-energy hypersurface (2011, 2012).
    --    A new, generic definition of the class of Roskilde-simple systems has been proposed (2014).
    --    The quasiuniversality of single-component Roskilde-simple liquids has been connected to these liquids' hidden scale invariance and an analytical criterion for quasiuniversality has been derived (2014).
    --    The Narayanaswamy aging theory has been simplified into a differential equation valid for temperture jumps and justified from the Bochkov-Kuzovlev nonlinear fluctuation-dissipation theorem; moreover a microscopic expression for the material time has been identified (2015).


Glass and Time - Danish National Research Foundation Centre for Viscous Liquid Dynamics, the Roskilde University glass group.


II. Ac conduction in disordered solids

   
Collaborating with Thomas Schrøder, we have studied the random barrier model numerically as well as analytically (2000, 2002, 2008).


III. Other research interests:



Workshops, etc:


VISCOUS LIQUIDS AND THE GLASS TRANSITION (XIV) (International workshop, June 16-18, 2016).
TOPICAL MEETING ON MOLECULAR DYNAMICS (Informal workshop, August 24, 2015).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (XIII) (
International workshop, May 28-30, 2015).
ROLLING RESISTANCE - THIRD COOEE WORKSHOP (International workshop, November 27-28, 2014).
DISCUSSION MEETING ON AGGREGATION AND CLUSTERING OF MOLECULES (International workshop, October 30-31, 2014).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (XII) (International workshop, June 12-14, 2014).
TOPICAL MEETING ON MOLECULAR DYNAMICS (Informal workshop, May 26, 2014).
GREEN ROAD INFRASTRUCTURE - SECOND COOEE WORKSHOP (International workshop, November 28-29, 2013).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (XI) (International workshop, May 23-25, 2013).
ROLLING RESISTANCE – AN EXPLORATORY WORKSHOP (International workshop, November 29-30, 2012).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (X) (
International workshop, June 7-9, 2012).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (IX) (International workshop, June 16-18, 2011).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (VIII) (International workshop, May 28-30, 2010).
AGING OF SLOWLY RELAXING SYSTEMS (Ph.D. summer school, June 19-24, 2009).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (VII) (International workshop, April 24-26, 2009).
FRAGILITY OF VISCOUS LIQUIDS: CAUSE(S) AND CONSEQUENCES (International workshop, Carlsberg Academy, October 8-10, 2008).
LINEAR RESPONSE: THEORY AND PRACTICE (Ph.D. summer school, July 1-8, 2007).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (VI) (International workshop, June 29 - July 1, 2007).
FLOW PROCESSES (3 DNRF-centre workshop, May 9, 2007).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (V) (International workshop, May 26-28, 2006).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (IV) (International workshop, June 3-5, 2005).
STRUCTURE AND DYNAMICS OF METALS AND GLASSES (RUC-Risø workshop, June 4, 2003).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (III) (International workshop, May 9-11, 2003).
RELAXATIONS AND RHEOLOGY OF VISCOUS LIQUIDS AND GLASSES (RUC-AUC-Rockwool workshop, November 11, 2002).
BIOLOGICALLY RELEVANT PHYSICS (RUC-SDU-KVL workshop, March 25, 2002).
VISCOUS LIQUIDS AND THE GLASS TRANSITION (II) (International workshop, June 16-18, 2000).






Scientific publications:


Pair potential that reproduces the shape of isochrones in molecular liquids [with Veldhorst and Schrøder], J. Phys. Chem. B 120, 7970 (2016).
Thermodynamics of freezing and melting [with Pedersen, Costigliola, Bailey, and Schrøder], Nat. Commun. 7, 12386 (2016).
Simple liquids' quasiuniversality and the hard-sphere paradigm, J. Phys.: Condens. Matter 28, 323001 (2016).
Studies of the Lennard-Jones fluid in 2, 3, and 4 dimensions highlight the need for a liquid-state 1/d expansion [with Costigliola and Schrøder], J. Chem. Phys. 144, 231101 (2016).
Freezing and melting line invariants of the Lennard-Jones system [with Costigliola and Schrøder], Phys. Chem. Chem. Phys. 18, 14678 (2016).
Thermalization Calorimetry: A simple method for investigating glass transition and crystallization of supercooled liquids [with Jakobsen et al.], AIP Adv. 6, 055019 (2016).
Continuum nanofluidics [with Hansen, Daivis, Todd, and Bruus], Langmuir 31, 13275 (2015).
Hidden scale invariance of metals [with Hummel, Kresse, and Pedersen], Phys. Rev. B 92, 174116 (2015).
Scaling of the dynamics of flexible Lennard-Jones chains. Effects of harmomic bonds [with Veldhorst and Schrøder], J. Chem. Phys. 143, 194503 (2015).
Narayanaswamy’s 1971 aging theory and material time, J. Chem. Phys. 143, 114507 (2015).
Invariants in the Yukawa system’s thermodynamic phase diagram [with Veldhorst and Schrøder], Phys. Plasmas 22, 073705 (2015).
Direct tests of single-parameter aging [with Hecksher and Olsen], J. Chem. Phys. 142, 241103 (2015).
RUMD: A general purpose molecular dynamics package [with Bailey, Ingebrigtsen, Hansen, Veldhorst, Bøhling, Lemarchand, Olsen, Bacher, Larsen, and Schrøder], arXiv:1506.05094.
A review of experiments testing the shoving model [with Hecksher], J. Non-Cryst. Solids 407, 14 (2015).
Isomorph theory prediction for the dielectric loss variation along an isochrone [with Xiao, Tofteskov, Christensen, and Niss ], J. Non-Cryst. Solids 407, 190 (2015).
Rolling Resistance Measurement and Model Development [with Andersen, Larsen, Fraser, and Schmidt], ACSE J. Transp. Eng. 140, 04014075 (2015).
Simplicity of condensed matter at its core: Generic definition of a Roskilde-simple system [with Schrøder], J. Chem. Phys. 141, 204502 (2014).
Density scaling and quasiuniversality of flow-event statistics for athermal plastic flows [with Lerner and Bailey], Phys. Rev. E 90, 052304 (2014).
Explaining why simple liquids are quasi-universal [with Bacher and Schrøder], Nature Commun. 5, 5424 (2014).
Variation of the dynamic susceptibility along an isochrone [with Bailey and Schrøder], Phys. Rev. E 90, 042310 (2014).
Cooee bitumen. II. Stability of linear asphaltene nanoaggregates [with Lemarchand, Schrøder, and Hansen], J. Chem. Phys. 141, 144308 (2014).
Isomorph invariance of the structure and dynamics of classical crystals [with Albrechtsen, Olsen, Pedersen, and Schrøder], Phys. Rev. B 90, 094106 (2014).
Hidden scale invariance in condensed matter, J. Phys. Chem. B 118, 10007 (2014).
Scaling of the dynamics of flexible Lennard-Jones chains [with Veldhorst and Schrøder], J. Chem. Phys. 141, 054904 (2014).
The mother of all pair potentials [with Bacher], Colloid. Polym. Sci. 292, 1971 (2014).
Oscillatory shear and high-pressure dielectric study of 5-methyl-3-heptanol [with Gainaru et al.], Colloid. Polym. Sci. 292, 1913 (2014).
The dynamic bulk modulus of three glass-forming liquids [with Gundermann, Niss, Christensen, and Hecksher], J. Chem. Phys. 140, 244508 (2014).
The impact range for smooth wall–liquid interactions in nanoconfined liquids [with Ingebrigtsen], Soft Matter 10, 4324 (2014).
Estimating the density-scaling exponent of a monatomic liquid from its pair potential [with Bøhling, Bailey, and Schrøder], J. Chem. Phys. 140, 124510 (2014).
Entropy and relaxation time, pp. 81-90 in "Fragility of Glass-Forming Liquids", Eds. A. L. Greer, K. F. Kelton, S. Sastry (Hindustan Book Agency, New Delhi, 2014); arXiv:1403.2684 (2014).
Shear-modulus investigations of monohydroxy alcohols: Evidence for a short-chain-polymer rheological response [with Gainaru, Figuli, Hecksher, Jakobsen, Wilhelm, Böhmer], Phys. Rev. Lett. 112, 098301 (2014).
Predicting how nanoconfinement changes the relaxation time of a supercooled liquid [with Ingebrigtsen, Errington, and Truskett], Phys. Rev. Lett. 111, 235901 (2013).
Statistical mechanics of Roskilde liquids: Configurational adiabats, specific heat contours, and density dependence of the scaling exponent [with Bailey, Bøhling, Veldhorst, and Schrøder], J. Chem. Phys. 139, 184506 (2013).
The Rosenfeld-Tarazona expression for liquids’ specific heat: A numerical investigation of eighteen systems [with Ingebrigtsen, Veldhorst, and Schrøder], J. Chem. Phys. 139, 171101 (2013).
Isomorphs, hidden scale invariance, and quasiuniversality, Phys. Rev. E 88, 042139 (2013).
Cooee bitumen: Chemical aging [with Lemarchand, Schrøder, and Hansen], J. Chem. Phys. 139, 124506 (2013).
Two measures of isochronal superposition [with Roed, Gundermann, and Niss],  J. Chem. Phys. 139, 101101 (2013).
A cool liquid that does not freeze ['News and Views'], Nature Phys. 9, 535 (2013).
Aging of CKN: Modulus versus conductivity analysis, Phys. Rev. Lett. 110, 245901 (2013).
Isomorph invariance of Couette shear flows simulated by the SLLOD equations of motion [with Separdar, Bailey, Schrøder, and Davatolhagh], J. Chem. Phys. 138, 154505 (2013).
Four-component united-atom model of bitumen [with Hansen, Lemarchand, Nielsen, and Schrøder], J. Chem. Phys. 138, 094508 (2013).
Mechanical spectra of glass-forming liquids.  I. Low-frequency bulk and shear moduli of DC704 and 5-PPE measured by piezoceramic transducers [with Hecksher, Olsen, Nelson, and Christensen], J. Chem. Phys. 138, 12A543 (2013).
Mechanical spectra of glass-forming liquids. II. Gigahertz-frequency longitudinal and shear acoustic dynamics in glycerol and DC704 studied by time-domain Brillouin scattering [with Klieber, Hecksher, Pezeril, Torchinsky, and Nelson], J. Chem. Phys. 138, 12A544 (2013).
NVU perspective on simple liquids’ quasiuniversality, Phys. Rev. E 87, 022106 (2013).
Generalized extended Navier-Stokes theory: Correlations in molecular fluids with intrinsic angular momentum [with Hansen, Daivis, Todd, Bruus], J. Chem. Phys. 138, 034503 (2013).
Do the repulsive and attractive pair forces play separate roles for the physics of liquids? [with Bøhling, Veldhorst, Ingebrigtsen, Bailey, Hansen, Toxværd, and Schrøder], J. Phys.: Condens. Matter 25, 032101 (2013).
NVU dynamics. III. Simulating molecules at constant potential energy [with Ingebrigtsen], J. Chem. Phys. 137, 244101 (2012).
“Cooling by heating” – demonstrating the significance of the longitudinal specific heat [with Papini and Christensen], Phys. Rev. X 2, 041015 (2012).
Scaling of viscous dynamics in simple liquids: Theory, simulation and experiment [with Bøhling, Ingebrigtsen, Grzybowski, Paluch, and Schrøder], New J. Phys. 14, 113035 (2012).

Experimental studies of Debye-like process and structural relaxation in mixtures of 2-ethyl-1-hexanol and 2-ethyl-1-hexyl bromide [with Preuss, Gainaru, Hecksher, Bauer, Richert, and Böhmer], J. Chem. Phys. 137, 144502 (2012).

Measurement of the four-point susceptibility of an out-of-equilibrium colloidal solution of nanoparticles using time-resolved light scattering [with Maggi, Di Leonordo, and Ruocco], Phys. Rev. Lett. 109, 097401 (2012).
Shear and dielectric responses of propylene carbonate, tripropylene glycol, and a mixture of two secondary amides [with Gainaru, Hecksher, Olsen, and Böhmer], J. Chem. Phys. 137, 064508 (2012).
CO2 emission reduction by exploitation of rolling resistance modelling of pavements [with Schmidt], Procedia 48, 311 (2012).
The instantaneous shear modulus in the shoving model [with Wang], J. Chem. Phys. 136, 224108 (2012).
Energy conservation in molecular dynamics simulations of classical systems [with Toxværd and Heilmann], J. Chem. Phys. 136, 224106 (2012).
Simplistic Coulomb forces in molecular dynamics: Comparing the Wolf and shifted-force approximations [with Schmidt and Schrøder], J. Phys. Chem. B 116, 5738 (2012).
Dynamic thermal expansivity of liquids near the glass transition [with Niss, Gundermann, and Christensen], Phys. Rev. E 85, 041501 (2012).
What is a simple liquid? [with Ingebrigtsen and Schrøder], Phys. Rev. X 2, 011011 (2012).
Identical temperature dependence of the time scales of several linear-response functions of two glass-forming liquids [with Jakobsen, Hecksher, Christensen, Olsen, and Niss], J. Chem. Phys. 136, 081102 (2012).
Thermodynamics of condensed matter with strong pressure-energy correlations [with Ingebrigtsen, Bøhling, and Schrøder], J. Chem. Phys. 136, 061102 (2012).
Isomorphs in the phase diagram of a model liquid without inverse power law repulsion [with Veldhorst, Bøhling, and Schrøder], Eur. Phys. J. B 85, 21 (2012).
Isomorphs in model molecular liquids [with Ingebrigtsen and Schrøder], J. Phys. Chem. B 116, 1018 (2012).
Predicting the density scaling exponent from Prigogine-Defay ratio measurements [with Gundermann, Pedersen, Hecksher, Bailey, Jakobsen, Christensen, Olsen, Schrøder, Fragiadakis, Casalini, Roland, and Niss], Nature Phys. 7, 816 (2011).
Role of the first coordination shell in determining the equilibrium structure and dynamics of simple liquids [with Toxværd], J. Chem. Phys. 135, 134501 (2011).
Nanoflow hydrodynamics [with Hansen, Daivis, Todd, and Bruus], Phys. Rev. E 84, 036311 (2011).
NVU dynamics.  I. Geodesic motion on the constant-potential-energy hypersurface [with Ingebrigtsen, Toxværd, Heilmann, and Schrøder], J. Chem. Phys. 135, 104101 (2011).
NVU dynamics. II. Comparing to four other dynamics [with Ingebrigtsen, Toxværd, and Schrøder], J. Chem. Phys. 135, 104102 (2011).
Simulations of crystallization in supercooled nanodroplets in the presence of a strong exothermic solute [with Toxværd and Larsen], J. Phys. Chem. C 115, 12808 (2011).
Pressure-energy correlations in liquids. V. Isomorphs in generalized Lennard-Jones systems [with Schrøder, Gnan, Pedersen, and Bailey], J. Chem. Phys. 134, 164505 (2011).
Do all liquids become strongly correlating at high pressure? [with Papini and Schrøder], arXiv:1103.4954 (2011).
Shifted forces in molecular dynamics [with Toxværd], J. Chem. Phys. 134, 081102 (2011).
Beta relaxation in the shear mechanics of viscous liquids: Phenomenology and network modeling of the alpha-beta merging region [with Jakobsen, Niss, Maggi, Olsen, and Christensen], J. Non-Cryst. Solids 357, 267 (2011).
Strongly correlating liquids and their isomorphs [with Pedersen, Gnan, Bailey, and Schrøder], J. Non-Cryst. Solids 357, 320 (2011).
A combined measurement of thermal and mechanical relaxation [with Christensen, Jakobsen, Papini, Hecksher, and Olsen], J. Non-Cryst. Solids 357, 346 (2011).
Physical aging of molecular glasses studied by a device allowing for rapid thermal equilibration [with Hecksher, Olsen, and Niss], J. Chem. Phys. 133, 174514 (2010).
Repulsive reference potential reproducing the dynamics of a liquid with attractions [with Pedersen and Schrøder], Phys. Rev. Lett. 105, 157801 (2010).
Connection between slow and fast dynamics of molecular liquids around the glass transition [with Niss, Dalle-Ferrier, Frick, Russo, and Alba-Simionesco], Phys. Rev. E 82, 021508 (2010).
Aging effects manifested in the potential-energy landscape of a model glass former [with Rehwald, Gnan, Heuer, Schrøder, and Diezemann], Phys. Rev. E 82, 021503 (2010).
Time reversible molecular dynamics algorithms with holonomic bond constraints in the NPH and NPT ensembles using molecular scaling [with Ingebrigtsen, Heilmann, and Toxværd], J. Chem. Phys. 132, 154106 (2010).
Predicting the effective temperature of a glass [with Gnan, Maggi, and Schrøder], Phys. Rev. Lett. 104, 125902 (2010).
Geometry of slow structural fluctuations in a supercooled binary alloy [with Pedersen, Schrøder, and Harrowell], Phys. Rev. Lett. 104, 105701 (2010).
Generalized fluctuation-dissipation relation and effective temperature in off-equilibrium colloids [with Maggi, Di Leonardo, and Ruocco], Phys. Rev. B 81, 104201 (2010).
Correlated volume-energy fluctuations of phospholipid membranes: A simulation study [with Pedersen, Peters, and Schrøder], J. Phys. Chem. B 114, 2124 (2010).
An electrical circuit model of the alpha-beta merging seen in dielectric relaxation of ultraviscous liquids (with Sağlanmak, Nielsen, Olsen, and Niss), J. Chem. Phys. 132, 024503 (2010).
Pressure-energy correlations in liquids. III.  Statistical mechanics and thermodynamics of liquids with hidden scale invariance [with Schrøder, Bailey, Pedersen, and Gnan], J. Chem. Phys. 131, 234503 (2009).
Pressure-energy correlations in liquids. IV. "Isomorphs" in liquid phase diagrams [with Gnan, Schrøder, Pedersen, and Bailey], J. Chem. Phys. 131, 234504 (2009).
Hidden scale invariance in molecular van der Waals liquids: A simulation study [with Schrøder, Pedersen, Bailey, and Toxværd], Phys. Rev. E 80, 041502 (2009).
Time-reversible molecular dynamics algorithms with bond constraints [with Toxværd, Heilmann, Ingebrigtsen, and Schrøder], J. Chem. Phys. 131, 064102 (2009).
Stability of supercooled binary liquid mixtures [with Toxværd, Pedersen, and Schrøder], J. Chem. Phys. 130, 224501 (2009).
Estimating the density scaling exponent of viscous liquids from specific heat and bulk modulus data [with Pedersen, Hecksher, Jakobsen, Schrøder, Gnan, and Bailey], arXiv:0904.3537 (2009).
A brief critique of the Adam–Gibbs entropy model [with Hecksher and Niss], J. Non-Cryst. Solids 355, 624 (2009).
Prevalence of approximate squareroot(time) relaxation for the dielectric alpha process in viscous organic liquids [with Nielsen, Christensen, Jakobsen, Niss, Olsen, and Richert], J. Chem. Phys. 130, 154508 (2009).
Fundamental questions relating to ion conduction in disordered solids [with Maass, Roling, and Sidebottom], Rep. Prog. Phys. 72, 046501 (2009).
Exponential distributions of collective flow-event properties in viscous liquid dynamics [with Bailey and Schrøder], Phys. Rev. Lett. 102, 055701 (2009).
Supercooled liquid dynamics studied via shear-mechanical spectroscopy [with Maggi, Jakobsen, Christensen, and Olsen], J. Phys. Chem. B 112, 16320 (2008).
Pressure dependence of the dielectric loss minimum slope for ten molecular liquids [with Nielsen, Pawlus, and Paluch], Phil. Mag. 88, 4101 (2008).
Investigation of the shear-mechanical and dielectric relaxation processes in two monoalcohols close to the glass transition [with Jakobsen, Maggi, and Christensen], J. Chem. Phys. 129, 184502 (2008).
Solution of the spherically symmetric linear thermoviscoelastic problem in the inertia-free limit [with Christensen], Phys. Rev. E 78, 021501 (2008).
Little evidence for dynamic divergences in ultraviscous molecular liquids [with Hecksher, Nielsen, and Olsen], Nature Phys. 4, 737 (2008).
Ac hopping conduction at extreme disorder takes place on the percolating cluster [with Schrøder], Phys. Rev. Lett. 101, 025901 (2008).
Pressure-energy correlations in liquids. I.   Results from computer simulations [with Bailey, Pedersen, Gnan, and Schrøder], J. Chem. Phys. 129, 184507 (2008).
Pressure-energy correlations in liquids. II. Analysis and consequences [with Bailey, Pedersen, Gnan, and Schrøder], J. Chem. Phys. 129, 184508 (2008).
Glass-forming liquids: One or more “order” parameters? [with Bailey, Christensen, Jakobsen, Niss, Olsen, Pedersen, and Schrøder], J. Phys. Condens. Matter 20, 244113 (2008).
Can the frequency-dependent isobaric specific heat be measured by thermal effusion methods? [with Christensen and Olsen], AIP Conf. Proc. 982, 139 (2008).
Volume-energy correlations in the slow degrees of freedom of computer-simulated phospholipid membranes [with Pedersen, Peters, and Schrøder], AIP Conf. Proc. 982, 407 (2008).
A cryostat and temperature control system optimized for measuring relaxations of glass-forming liquids [with Igarashi et al.], Rev. Sci. Instrum. 79, 045105 (2008).
An impedance-measurement setup optimized for measuring relaxations of glass-forming liquids [with Igarashi et al.], Rev. Sci. Instrum. 79, 045106 (2008).
Feasibility of single-parameter description of equilibrium viscous liquid dynamics [with Pedersen, Christensen, and Schrøder], Phys. Rev. E 77, 011201 (2008).
Mysteries of the glass transition - Letter commenting on a Reference Frame by James Langer, Physics Today 61 (1), 15 (2008).
Strong pressure-energy correlations in van der Waals liquids [with Pedersen, Bailey, and Schrøder], Phys. Rev. Lett. 100, 015701 (2008).
Solidity of viscous liquids. V. Long-wavelength dominance of the dynamics, Phys. Rev. E 76, 041508 (2007).
Crystallization of the Wahnström Binary Lennard-Jones Liquid [with Pedersen, Bailey, and Schrøder], arXiv:0706.0813 (2007).
Ten themes of viscous liquid dynamics, J. Phys.: Condens. Matter 19, 205105 (2007).
Conventional methods fail to measure cp(omega) of glass-forming liquids [with Christensen and Olsen], Phys. Rev. E 75, 041502 (2007).
Dominance of shear elastic energy far from a point defect in a solid, Phys. Rev. B 75, 092102 (2007).
Violations of conservation laws in viscous liquid dynamics, Philos. Mag. 87, 497 (2007).
Hopping models for ion conduction in noncrystals [with Schrøder], in "Superionic Conductor Physics" (World Scientific, Singapore, 2007), p. 97 (2007).
Single-order-parameter description of glass-forming liquids: A one-frequency test [with Ellegaard, Christensen, Christiansen, Olsen, Pedersen, and Schrøder], J. Chem. Phys. 126, 074502 (2007).
Solidity-induced crystallization of ultraviscous water (January, 2007).
On the possible existence of crystallites in glass-forming liquids, cond-mat/0612671 (2006).
An energy landscape model for glass-forming liquids in three dimensions [with Pedersen, Hecksher, and Schrøder], J. Non-Cryst. Solids 352, 5210 (2006).
Elastic models for the non-Arrhenius viscosity of glass-forming liquids [with Christensen and Olsen], J. Non-Cryst. Solids 352, 4635 (2006).
The glass transition and elastic models of glass-forming liquids, Rev. Mod. Phys. 78, 953 (2006).
Solidity of viscous liquids. IV. Density fluctuations, Phys. Rev. E 74, 021502 (2006).
Elastic models for the non-Arrhenius relaxation time of glass-forming liquids, AIP Conf. Proc. 832, 113 (2006).
A model for the generic alpha relaxation of viscous liquids, Europhys. Lett. 71, 646 (2005).
Solidity of viscous liquids. III. Alpha relaxation, Phys. Rev. E 72, 011501 (2005).
Glasses: Heirs of liquid treasures ['News and Views'], Nature Materials 3, 749 (2004).
Landscape equivalent of the shoving model [with Olsen], Phys. Rev. E 69, 042501 (2004).
Minimal model for beta relaxation in viscous liquids [with Olsen], Phys. Rev. Lett. 91, 155703 (2003).
Is there a 'native' band gap in ion conducting glasses?, J. Non-Cryst. Solids 324, 192 (2003).
Computer simulations of the random barrier model [with Schrøder], Phys. Chem. Chem. Phys. 4, 3173 (2002).
Hopping models and ac universality [with Schrøder], Phys. Stat. Sol. (b) 230, 5 (2002).
Time-temperature superposition in viscous liquids [with Olsen and Christensen], Phys. Rev. Lett. 86, 1271 (2001).
Beta relaxation of non-polymeric liquids close to the glass transition [with Olsen and Christensen], Phys. Rev. E 62, 4435 (2000).
Universality of ac conduction in disordered solids [with Schrøder], Rev. Mod. Phys. 72, 873 (2000).
Crossover to potential energy landscape dominated dynamics in a model glass-forming liquid [with Schrøder, Sastry, and Glotzer], J. Chem. Phys. 112, 9834 (2000).
Scaling and universality of ac conduction in disordered solids [with Schrøder], Phys. Rev. Lett. 84, 310 (2000).
Solidity of viscous liquids. II. Anisotropic flow events, Phys. Rev. E 59, 7243 (1999).
Solidity of viscous liquids, Phys. Rev. E 59, 2458 (1999).
Potential energy landscape signatures of slow dynamics in glass-forming liquids [with Sastry, Debenedetti, Stillinger, Schrøder, and Glotzer],  Physica A 270, 301 (1999).
Source of non-Arrhenius average relaxation time in glass-forming liquids, J. Non-Cryst. Solids 235-237, 142 (1998).
Hopping in a supercooled binary Lennard–Jones liquid [with Schrøder], J. Non-Cryst. Solids 235-237, 331 (1998).
Structural relaxation monitored by instantaneous shear modulus [with Olsen and Christensen], Phys. Rev. Lett. 81, 1031 (1998).
A Statistical Mechanical Approximation for the Calculation of Time Auto-Correlation Functions, arXiv: cond-mat/9712222 (1997).
Fluctuation-dissipation theorem for frequency-dependent specific heat [with Nielsen], Phys. Rev. B 54, 15754 (1996).
Effective one-dimensionality of universal ac hopping conduction in the extreme disorder limit [with Schrøder], Phys. Rev. B 54, 14884 (1996).
Universality of anomalous diffusion in extremely disordered systems [with Jacobsen],  Chem. Phys. 212, 61 (1996).
Comment on "Dynamic viscosity of a simple glass-forming liquid" [with Behrens, Christiansen, Christensen, and Olsen], Phys. Rev. Lett. 76, 1553 (1996).
Local elastic expansion model for viscous-flow activation energies of glass-forming molecular liquids [with Olsen and Christensen], Phys. Rev. B 53, 2171 (1996).
Universal time-dependence of the mean-square displacement in extremely rugged energy landscapes with equal minima [with Jacobsen], Phys. Rev. E 52, 2429 (1995).
Lunar phase influence on global temperatures, Science 269, 1284 (1995).
Energy master equation - a low-temperature approximation to Bässler's random-walk model, Phys. Rev. B 51, 12276 (1995).
Studies of ac hopping conduction at low temperatures, Phys. Rev. B 49, 11709 (1994).
Low-temperature universality in computer simulations of the macroscopic model for ac conduction in disordered solids [with Riedel], J. Non-Cryst. Solids 172-174, 1419 (1994).
Algorithm for fast determination of complex moduli [with Winther and Kramer], J. Rheol. 38, 1179 (1994).
Universal low-temperature ac conductivity of macroscopically disordered nonmetals, Phys. Rev. B 48, 12511 (1993).
Universal ac conductivity of nonmetallic disordered solids at low temperatures, Phys. Rev. B 47, 9128 (1993).
Langevin models for shear-stress fluctuations in flows of viscoelastic liquids, Phys. Rev. E 48, 400 (1993).
Towards a phenomenological definition of the term 'gel' [with Almdal, Hvidt, and Kramer], Polymer Gels and Networks 1, 5 (1993).
Some remarks on ac conduction in disordered solids, J. Non-Cryst. Solids 135, 219 (1991).
A 'zero-parameter' constitutive relation for simple shear viscoelasticity, Rheol. Acta 29, 145 (1990).
Maximum-entropy ansatz for nonlinear-response theory, Phys. Rev. A 40, 2207 (1989).
Correlation effects in ionic conductivity [with Murch], Crit. Rev. Solid State and Materials Sciences 15, 345 (1989).
Random free-energy barrier model for ac conduction in disordered solids, J. Appl. Phys. 64, 2456 (1988).
Unified formalism for excess current noise in random-walk models, Phys. Rev. B 37, 10143 (1988).
Tracer and physical correlation factors in diffusion [with Murch], Adv. Ceramics 23, 331 (1987).
Exponential band tails as a consequence of the glass transition, Key Engn. Mater. 13, 501 (1987).
Master-equation approach to the glass-transition, Phys. Rev. Lett. 58, 792 (1987).
A phenomenological model for the Meyer-Neldel rule, J. Phys. C: Solid State Phys. 19, 5655 (1986).
On the mechanism of glass ionic conductivity, J. Non-Cryst. Solids 88, 271 (1986).
Correlation effects in tracer diffusion and ionic conductivity II [with Murch], Solid State Ionics 21,139  (1986).
Correlation effects in tracer diffusion and ionic conductivity  I [with Murch], Solid State Ionics 20, 203 (1986).
A simple model of ac hopping conductivity, J. Physique Colloq. 46, C8-343 (1985).
A simple model of ac hopping conductivity in disordered solids, Phys. Lett. A 108, 457 (1985).
Conductivity correlation in systems of non-interacting particles, Philos. Mag. A 50, 585 (1984).
Non-standard characterizations of ideals in C(X), Math. Scand. 50, 44 (1982).




Press and other publications [in Danish]


Ny teori for smeltning og frysning (m. Ulf Pedersen), Aktuel Naturvidenskab, nr. 4, p. 19, 2016. 
Naturvidenskabelig dannelse, gæst i "Hjernekassen på P1", 25. januar, 2016.
Hvad med en naturvidenskablig kanon? (med Henriette Wase Hansen), Politiken 19. oktober, 2015.
Energibesparelse uden omkostning (med Jesper Larsen og Bjarne Schmidt), Børsens kronik 1. juli, 2015.
Professor: Nedlæg UVVU, Indlæg om Klarlund-sagen efter Østre Landsrets omstødelse af UVVU-dommen over hende, Altinget.dk, 17. marts, 2015; genoptrykt i BioZoom, September 2015.
Skyggepris. Bedre veje giver lavere CO2 udslip, (m. Jesper Larsen og Bjarne Schmidt), Analyse i Politiken, 4. juni, 2014.
I strid med sund fornuft (med en række andre), Weekendavisen 20. juni, 2014.
Hvordan kan atomer holde formen på en genstand?, Videnskab.dk, 12. maj, 2014.
Opråb til UVVU (med Gregersen, Hjorth og Nosch), Weekendavisen 11.oktober, 2013.
45 år med computersimuleringer, Videnskab.dk, 14. juli, 2013 (først publiceret i Dansk Kemi).
Verdens ældste fysikforsøg drypper igen, Berlingske 3. maj, 2013.
Cyklister er sunde – og cykling ligeså, Politiken 25. april, 2013.
Grafikkort sætter Newton på speed (m. Jesper Schmidt Hansen, Nicholas P. Bailey og Thomas Schrøder), Aktuel Naturvidenskab, nr. 1, 2013.
Rullemodstand. Sådan sparer vi energi på vejen (m. Jesper Larsen og Bjarne Schmidt), Analyse i Politiken, 28. november, 2012.
Glas kan smelte ved hjælp af kvantevibrationer, Videnskab.dk, 18. februar 2011.
Forskning i bedre asfalt kan spare bilister for millioner, Dagbladet Roskilde Tidende, 4. februar 2011.
Bedre asfalt skal reducere CO2-udledningen, Videnskab.dk, 24. januar 2011.
Bedre asfalt skal spare benzin, Politiken 23. januar 2011.
P1 morgenindslag, 16.januar 2010.
Videnskabens Verden, Program på P1, 16. januar 2010.
Den fjerde tilstand, Weekendavisen, 16. oktober, 2009.

Glas er ikke bare glas. Nyhedsindslag i TV2 Lorry, 18. september 2009.
Overraskelsesangreb ramte forsiden, Videnskab.dk, 22. januar, 2009.
Termiske fluktuationer – er der noget nyt under Solen?, (m. Ulf Pedersen og Thomas Schrøder) Kvant (Tidsskrift for Fysik og Astronomi) 19 (4),  26 (2008).
100 milliarder sole i Mælkevejen, Weekendavisens minikronik, 4. januar, 2008.
Glastilstanden, Naturens Verden 7/8, 47 (2007).
Glas - en sej væske!, Hippocampus 13/05 2007.
Glas - den fjerde tilstandsform, Aktuel Naturvidenskab, nr. 2, 2006.
Seje væskers fysik, debut på Politikens ny serie "Kedsomologi", 8. januar, 2006.
Seje væsker og glasovergangen (m. Thomas Schrøder), Kvant (Tidsskrift for Fysik og Astronomi) 17 (1),  12 (2006).
Interview i "Glas" - Tidsskrift for Glarmesterlauget i Danmark, Efterår 2005 (side 10-11).
Interview i forbindelse med Connect Denmark arrangementet "Meet the researcher",  September 2005.
En introduktion til mekanik, indledning til SMÆK på mekanikken - Experimentariums skolekonkurrence 2005 for 3. og 4. klasser, juli 2005.
Omtale og interview i RUC-NYT i forbindelse med centeråbningen d. 2. juni 2005 (side 3).
Universitetslisten, program ved valget af VIP-repræsentant i RUCs bestyrelse, maj, 2004.
Tre sandheder om projektarbejdet: Fra "Ja" til "Tja", indlæg ved IMFUFAs jubilæumskonference, oktober, 2003.
Forskningsfrihed i fare (m. Mogens Niss), debatindlæg i Jyllands-Posten, 17. februar, 2003.
Faglig nedtur, Politikens kronik, 7. januar, 2003.
Back to basics!, Kvant (Tidsskrift for Fysik og Astronomi) 13 (3), 34 (2002).
Fysikkens æstetik, festtalen ved RUCs årsfest d. 21. september, 2001.
Når en væske "glasser" (m. Tage Christensen og Niels Boye Olsen)- kort og populært om vores forskning (fra RUC-NYT, 1997/98).






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