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The last few years have seen an extraordinary growth of interest in
complex systems. From physics to biology, from economics
to cognitive sciences, a new vocabulary is emerging to describe
discoveries about wide-ranging and fundamental phenomena.
Statistical Mechanics has become in the last decades the standard tool
to study problems once considered to be out of the reach
and the scopes of Physics.
It has been in fact applied to the study of the complex behavior of
various kinds of systems of areas such as biological and sociological
sciences, finance, economy, theory of decisions, networks.
In particular several disciplines connected with Engineering are now
attracting more and more the interest of physicsts.
Granular matter is a remarkable example of these new disciplines.
The problem of understanding granular materials is widely recognized
as one of the main problems of engineering and industry. A
brief list of typical "granular" products comprehends: grains,
powders, sands, pills, seeds and similar particulate materials. More
generally, granular materials are a very large set of substances used
in the industry and in the everyday life: ceramics, fertilizers,
cosmetics, food products, paper, conductor pastes, resins,
electronics, polymers, suspensions, solid chemicals, construction
materials and so on. The international economic impact of particle
processing is substantial. The value added by manufacture that
involves particulate has been estimated to be a minimum of 80/100
billion/year, which is of the order of the US trade deficit with
Japan. The US Dept. of Commerce has estimated the total economic
impact of particulate products to be one trillion/year. Despite
economic impact, however, insufficient attention is paid to
difficulties associated with the processing of particles. An improved
understanding of micromechanics of granular media requires an
interdisciplinary approach involving both physicists and
engineers.
Mechanical engineers and geologists have studied Granular Matter for at least
two centuries and found several empirical laws describing its behavior.
Physicists have joined in more recently and
are interested in formulating general laws. For them granular matter is
a new type of condensed matter, showing two states: one fluid-like,
one solid-like. But there is not yet consensus on the description of these
two states. According to P.G. de Gennes Granular matter now is at the level
of solid-state physics in 1930.
Granular matter also represents an important paradigm for the study of
non-equilibrium stationary states. Due to the dissipative nature of the
interactions granular gases have to be considered as open systems
and therefore concepts from equilibrium thermodynamics cannot be applied,
at least in straightforward way.
The project we propose focuses on granular fluids.
We intend by granular fluid a large number of particles, whose
size is larger than a micron, colliding
with one another and losing a little energy in each collision.
Below one micron thermal agitation is important and Brownian motion
can be observed. Above one micron, thermal agitation is negligible.
However,if such a system is shaken to keep it in motion,
its dynamics resembles that of fluids, in that the grains move randomly.
One of the key differences between a granular material and a regular
fluid is that the grains of the former lose energy with each
collision, while the molecules of the latter do not. Even when the
inelasticity of the collisions is small, it can give rise to dramatic
effects, including the Maxwell Demon effect and
the phenomenon of granular clustering. Experiments and molecular dynamics
simulations alike show that granular gases in the
absence of gravity do not become homogeneous with time, but instead
form dense clusters of stationary particles surrounded by a lower
density region of more energetic particles. From a particulate point
of view, one can explain these clusters by noting that when a particle
enters a region of slightly higher density, it has more collisions,
loses more energy, and so is less able to leave that region, thus
increasing the local density and making it more likely for the next
particle to be captured.
Original papers
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1
- U. Marini Bettolo Marconi and M. Conti:
Dynamics of vibrofluidized granular gases in periodic structures,
Physical Review E 69, 011302 (2004) .
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2
- U. M. B. Marconi and A. Puglisi
Statistical mechanics of granular gases in compartmentalized systems
Physical Review E 68, 031306 (2003) .
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- Noise Activated Granular Dynamics
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F. Cecconi, A. Puglisi, U. M. B. Marconi, and A. Vulpiani
Phys. Rev. Lett. 90, 064301 (2003)
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- J. M. Romero-Enrique, L. F. Rull, and U. M. Bettolo Marconi
Surface and capillary transitions in an associating binary mixture model
Phys. Rev. E 67, 041502 (2003)
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J. M. Romero Enrique, I. Rodriguez Ponce, L. F. Rull
and Umberto Marini Bettolo Marconi
Complex fluid behavior of strongly asymmetric
binary mixtures. Thermodynamic properties
of a generalized Lin-Taylor model.
Molecular Physics 93, 501 (1998).
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J. M. Romero Enrique, I. Rodriguez Ponce, L. F. Rull y
Umberto Marini Bettolo Marconi.
Critical exponents in the Lin-Taylor model of asymmetrical
binary mixtures
Molecular Physics, 95 , 571 (1998).
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R. Pagnani, U. M. Bettolo Marconi, and A. Puglisi
Driven low density granular mixtures
Phys. Rev. E 051304 (2002)
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3
- U. M. B. Marconi and A. Puglisi
Steady-state properties of a mean-field model of driven inelastic mixtures
Phys. Rev. E 66, 011301 (2002)
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5
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U. M. B. Marconi and A. Puglisi
Mean-field model of free-cooling inelastic mixtures
Phys. Rev. E 65, 051305 (2002)
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A. Baldassarri, U. Marini Bettolo Marconi, and A. Puglisi
Cooling of a lattice granular fluid as an ordering process
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Phys. Rev. E 65, 051301 (2002)
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- Baldassarri, U. M. B. Marconi, A. Puglisi, and A. Vulpiani
Driven granular gases with gravity
Phys. Rev. E 64, 011301 (2001)
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M. Conti and U. Marini Bettolo Marconi
Groove instability in cellular solidification
Phys. Rev. E 63, 011502 (2001)
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- Puglisi, V. Loreto, U. Marini Bettolo Marconi, and A. Vulpiani
Kinetic approach to granular gases
Phys. Rev. E 59, 5582-5595 (1999)
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- Puglisi, V. Loreto, U. M. B. Marconi, A. Petri, and A. Vulpiani
Clustering and Non-Gaussian Behavior in Granular Matter
Phys. Rev. Lett. 81, 3848-3851 (1998)
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U. M. B. Marconi
Interface pinning and slow ordering kinetics on infinitely ramified fractal
structures
Phys. Rev. E 57, 1290-1301 (1998)
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J. M. Romero-Enrique, I. Rodriguez-Ponce, L. F. Rull,
and U. M. B. Marconi
Comment on Exact Results for the Lower Critical
Solution in the Asymmetric Model of an Interacting Binary Mixture
Phys. Rev. Lett. 79, 3543 (1997)
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U. M. B. Marconi, A. Crisanti, and G. Iori
Soluble phase field model
Phys. Rev. E 56, 77-87 (1997)
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M. Conti, F. Marinozzi, and U. Marini Bettolo Marconi
Diffusion-controlled growth of a solid cylinder into its undercoded melt:
Instabilities and pattern formation studied with the phase-field model
Phys. Rev. E 55, 3087-3091 (1997)
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U. M. B. Marconi and A. Petri
Domain growth on self-similar structures
Phys. Rev. E 55, 1311-1314 (1997)
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U. M. B. Marconi and A. Crisanti
Growth kinetics in a phase field model with continuous symmetry
Phys. Rev. E 54, 153-162 (1996)
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- M. Somoza, U. M. B. Marconi, and P. Tarazona
Growth in systems of vesicles and membranes
Phys. Rev. E 53, 5123-5129 (1996)
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F. Marinozzi, M. Conti, and U. M. B. Marconi
Phase-field model for dendritic growth in a channel
Phys. Rev. E 53, 5039-5043 (1996)
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U. M. B. Marconi and A. Crisanti
Diffusion Limited Growth in Systems with Continuous Symmetry
Phys. Rev. Lett. 75, 2168-2171 (1995)
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M. Falcioni, U. M. B. Marconi, P. M. Ginanneschi, and A. Vulpiani
Complexity of the Minimum Energy Configurations
Phys. Rev. Lett. 75, 637-640 (1995)
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- Crisanti and U. M. B. Marconi
Effective action method for the Langevin equation
Phys. Rev. E 51, 4237-4245 (1995)
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U. M. B. Marconi and A. Maritan
Deflated regime for pressurized ring polymers with long-range interactions
Phys. Rev. E 47, 3795-3798 (1993)
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M. Falcioni, U. M. B. Marconi, and A. Vulpiani
Ergodic properties of high-dimensional symplectic maps
Phys. Rev. A 44, 2263-2270 (1991)
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U. M. B. Marconi and B. L. Gyorffy
Structure of the liquid-vapor interface:
A nonperturbative approach to the theory of interfacial fluctuations
Phys. Rev. A 41, 6732-6740 (1990)
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U. M. B. Marconi and F. Van Swol
Microscopic model for hysteresis and phase equilibria of fluids
confined between parallel plates
Phys. Rev. A 39, 4109-4116 (1989)
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U. M. B. Marconi
Critical adsorption and finite-geometry effects
Phys. Rev. A 38, 6267-6279 (1988)
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R. Evans and U. M. B. Marconi
Comment on Simple theory for the critical adsorption of a fluid
Phys. Rev. A 34, 3504-3507 (1986)
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R. Evans and U. Marini Bettolo Marconi
Capillary condensation versus prewetting
Phys. Rev. A 32, 3817-3820 (1985)
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Giulio
Costantini, Fabio Cecconi, and Umberto Marini-Bettolo-Marconi
Transport of a heated granular gas in a washboard potential
J. Chem. Phys. 125, 204711 (2006)
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Umberto Marini Bettolo Marconi and Pedro Tarazona
Nonequilibrium inertial dynamics of colloidal systems
J. Chem. Phys. 124, 164901 (2006)
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Umberto Marini-Bettolo-Marconi,
Maurizio Natali, Giulio Costantini, and Fabio Cecconi
Inelastic Takahashi hard-rod gas J. Chem. Phys. 124, 044507 (2006)
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Giulio Costantini, Umberto Marini Bettolo Marconi, Galina
Kalibaeva, and Giovanni Ciccotti
The inelastic hard dimer gas: A nonspherical model for granular
matter
J. Chem. Phys. 122, 164505 (2005)
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Fabio Cecconi, Umberto
Marini Bettolo Marconi, Fabiana Diotallevi, and Andrea Puglisi
Inelastic hard rods in a periodic potential
J. Chem. Phys. 121, 5125 (2004)
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Fabio Cecconi, Fabiana Diotallevi, Umberto Marini Bettolo Marconi, and
Andrea Puglisi
6. Fluid-like behavior of a one-dimensional granular gas
J. Chem. Phys. 120, 35 (2004)
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G. Costantini, C. Cattuto, D. Paolotti and U. Marini Bettolo Marconi,
Behavior of Granular Mixtures in Shaken Compartmentalized
Containers
Physica A 347, 411 (2005).
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Umberto Marini Bettolo Marconi and Pedro Tarazona
Dynamic density functional theory of fluids
J. Chem. Phys. 110, 8032 (1999)
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Aphrodite Papadopoulou, Frank van Swol, and Umberto
Marini Bettolo Marconi
8. Pore-end effects on adsorption hysteresis in cylindrical and
slitlike pores
J. Chem. Phys. 97, 6942 (1992)
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Ziming Tan, Umberto Marini
Bettolo Marconi, Frank van Swol, and Keith E. Gubbins
Hard-sphere mixtures near a hard wall
J. Chem. Phys. 90, 3704 (1989)
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Brian K. Peterson, Keith E. Gubbins, Grant
S. Heffelfinger, Umberto Marini Bettolo Marconi, and Frank van Swol
Lennard-Jones fluids in cylindrical pores: Nonlocal theory and
computer simulation
J. Chem. Phys. 88, 6487 (1988)
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R. Evans and U. Marini Bettolo Marconi
Phase equilibria and solvation forces for fluids confined between
parallel walls
J. Chem. Phys. 86, 7138 (1987)
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R. Evans, U. Marini Bettolo Marconi, and P. Tarazona
Fluids in narrow pores: Adsorption, capillary condensation, and
critical points
J. Chem. Phys. 84, 2376 (1986)
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Corberi, Federico; Marconi, Umberto Marini Bettolo
O(N) model for charge density waves
Physica A Volume: 225, Issue: 3-4, April 1, 1996, pp. 281-293
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Conti, Massimo; Marconi, Umberto Marini Bettolo
Novel Monte-Carlo lattice approach to rapid directional
solidification of binary alloys
Physica A Volume: 277, Issue: 1-2, March 1, 2000, pp. 35-46
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Conti, Massimo; Marconi, Umberto Marini Bettolo
Fingering in slow combustion
Physica A Volume: 312, Issue: 3-4, September 15, 2002, pp. 381-391
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Conti, Massimo; Marconi, Umberto Marini Bettolo
Interfacial dynamics in rapid solidification processes
Physica A Volume: 280, Issue: 1-2, May 15, 2000, pp. 148-154
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Marconi, U. Marini Bettolo; Petri, A.; Vulpiani, A.
Janssen's law and stress fluctuations in confined dry granular materials
Physica A Volume: 280, Issue: 3-4, June 1, 2000, pp. 279-288
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U. Marini Bettolo Marconi, M. Conti and A. Vulpiani
Motion of a granular particle on a rough line
Europhys. Lett. 51 No 6 (15 September 2000) 685-690
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A. Baldassarri, U. Marini Bettolo Marconi and A. Puglisi
Influence of correlations on the velocity statistics of scalar granular
gases
Europhys. Lett. 58 No 1 (April 2002) 14-20
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Umberto Marini Bettolo Marconi, Giulio Costantini and Daniela Paolotti
Granular gases in compartmentalized systems
J. Phys.: Condens. Matter 17 No 24 (22 June 2005) S2641-S2656
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Umberto Marini Bettolo Marconi and Pedro Tarazona
Dynamic density functional theory of fluids
J. Phys.: Condens. Matter 12 No 8A (28 February 2000) A413-A418
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M. Conti, U. Marini Bettolo Marconi and A. Crisanti
A microscopic model for solidification
Europhys. Lett. 47 No 3 (1 August 1999) 338-344
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<M. A. Munoz, U. Marini Bettolo Marconi and R. Cafiero
Phase separation in systems with absorbing states
Europhys. Lett. 43 No 5 (1 September 1998) 552-557
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Umberto Marini Bettolo Marconi and Alberto Petri
Time dependent Ginzburg - Landau model in the absence of
translational invariance. Non-conserved order parameter domain growth
J. Phys. A: Math. Gen. 30 No 4 (21 February 1997) 1069-1088
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M. Conti, F. Marinozzi and U. Marini Bettolo Marconi
Domain coarsening via heat diffusion: A numerical study with
the phase field model
Europhys. Lett. 36 No 6 (20 November 1996) 431-436
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F Brouers and U M B Marconi
On the antiferromagnetic phase in the Hubbard model
J. Phys. C: Solid State Phys. 15 No 26 (20 September 1982) L925-L928
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Dynamical properties of vibrofluidized granular mixtures
D. Paolotti, C. Cattuto, U. Marini Bettolo Marconi, A. Puglisi
Granular Matter 5, 75 (2003).
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Umberto Marini Bettolo Marconi, Federico Corberi
Time dependent Ginzburg-Landau equation for an N-component model of
self-assembled fluids
Europhysics Letters 30, 349 (1995)
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F. Corberi and U.Marini Bettolo Marconi
Growth kinetics in the $\Phi^6$ N-component model.
Non conserved order parameter
Modern Physics Letters B, 8, 1115 (1994).
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F.Corberi, U.Marini.Bettolo Marconi
Growth Kinetics in the $\Phi ^6$ N-Component Model. Conserved Order Parameter
Modern Physics Letters B, {\bf 8}, 1125 (1994)
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D. Dominici, U. Marini Bettolo Marconi
Effective Action Method for Computing Next to
Leading Corrections of $O(N)$ Models
Physics Letters B 319 171, (1993)
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U. Marini Bettolo Marconi, A. Puglisi and A. Baldassarri
Application of simple models to the study of nonequilibrium
behavior of inelastic gases.
Phase Transitions, 77, 863 (2004)
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A. Baldassarri, U. Marini Bettolo Marconi and A. Puglisi
Kinetics Models of Inelastic Gases}
Math. Mod. Meth. Appl. S. 12, 965 (2002)
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A. Baldassarri, U. Marini Bettolo Marconi and A. Puglisi
Velocity fluctuations in cooling granular gases
in Lecture Notes in Physics ``Granular Gas Dynamics''
edited by T.Poeschel and N. Brilliantov, Springer (2003)
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Other Papers
<-- Changed by: U. Marini Bettolo Marconi , 8-March-2007 -->
J. M. Carmona, U. M. B. Marconi, J. J. Ruiz-Lorenzo, and A. Tarancon
Critical properties of the Ising model on Sierpinski fractals:
A finite-size scaling-analysis approach
Phys. Rev. B 58, 14387-14396 (1998)
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R. Medina, U. Marini Bettolo Marconi, and S. J. Sciutto
Exact two-particle effective interaction and superconductivity in
the two-level Hubbard model
Phys. Rev. B 39, 4277-4284 (1989)
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U.Marini Bettolo Marconi and A.Maritan
Variational approach to the phase diagram of rigid membranes
International Journal of Modern Physics B , 4615 (1993).
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U.Marini Bettolo Marconi and Y.C.Zhang
Novel scaling behavior of directed polymers:
disorder distribution with long tails
Journalof Statistical Physics 61, 885 (1990).
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M.Bernaschi, L.Biferale, A.Fernandez,
U. Marini Bettolo Marconi,
R.Petronzio and A.Tarancon
The magnetic critical exponent in the three
state three dimensional Potts model
Physics Letters 240 B, 419 (1990).
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S.~Sciutto, U.~Marini Bettolo Marconi and R.~Medina
Monte Carlo simulations in fermionic systems:
the three band Hubbard model case
Physica A 171, 139 (1990).
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D.K.Chaturvedi, U. Marini Bettolo Marconi and
M.P.Tosi
Mode coupling theory of charge fluctuations spectrum
in a binary ionic liquid.
Il Nuovo Cimento 57B, 319 (1980).
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U.Marini Bettolo Marconi and N.H.March
Relativistic Theory of the binding energies of heavy
atomic ions
International Journal of Quantum Chemistry 20, 693 (1981).
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R.Evans, P.Tarazona and U.Marini Bettolo Marconi
On the failure of certain integral equations theories to
account for complete wetting at solid-fluid interfaces
Molecular Physics 50, 993 (1983).
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U.Marini Bettolo Marconi, J.Wiechen and F.Forstmann
The structure of size asymmetric electrolytes at charged
surfaces
Chemical Physics Letters 107, 609 (1984).
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P.Tarazona, U.Marini Bettolo Marconi and R.Evans
Pairwise correlations at a fluid-fluid interface:
influence of a wetting film
Molecular Physics 54, 1357 (1985).
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R.Evans and U.Marini Bettolo Marconi
The role of wetting films in capilllary condensation and
rise: influence of long-ranged forces
Chemical Physics Letters 114, 415 (1985).
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R.Evans,U.Marini Bettolo Marconi and
P.Tarazona
Capillary condensation and adsorption in cylindrical
and slit-like pores
Faraday Transactions II,82, 1763 (1986).
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E.Bruno, U.Marini Bettolo Marconi and R.Evans
Phase transitions in a confined lattice gas: prewetting
and capillary condensation
Physica A 141, 187 (1987).
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P.Tarazona, R.Evans and U.Marini Bettolo Marconi
Phase equilibria of fluid interfaces and
confined fluids
Molecular Physics 60, 573 (1987).
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G.S. Heffelfinger, Z. Tan, K.E. Gubbins, U. Marini
Bettolo Marconi and F. van Swol
Fluid mixtures in narrow cylindrical pores: Computer
simulation and Theory
International Journal of Thermophysics 9,
1051 (1988).
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U.Marini Bettolo Marconi and B.L. Gyorffy,
On the statistical mechanics of interfaces and
interfacial fluctuations
Physica A159, 221 (1989).
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U.Marini Bettolo Marconi and F. van Swol
A model of Hysteresis in narrow pores
Europhysics Letters 8, 531 (1989).
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G.S. Heffelfinger, Z. Tan, K.E. Gubbins, U. Marini Bettolo Marconi
and F. van Swol,
Lennard-Jones Mixtures in a Cylindrical Pore.
A Comparison of Simulation and Density Functional Theory
Molecular Simulation 2, 393 (1989).
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A.Fernandez, U. Marini Bettolo Marconi and A.Tarancon,
Phase diagram of the $Z(3)$ spin model in three
dimensions
Physics Letters B 217, 314 (1989).
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A.Fernandez, U. Marini Bettolo Marconi and
A.Tarancon,
Monte Carlo simulation and Variational study of the
phase diagram of the Potts three state model
Physica A 161, 284 (1989).
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M.Bernaschi, L.Biferale,
A.Fernandez, U.Marini Bettolo Marconi,
R.Petronzio and A.Tarancon
Renormalization Group study of the $d=3$, $q=3$
Potts model
Physics Letters
B 231, 157 (1989).
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U.Marini Bettolo Marconi and M.M. Telo da Gama
The crossover between complete wetting
and critical adsorption
Physica A 171, 69 (1991).
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U.Marini Bettolo Marconi and F. van Swol
Structure effects and phase equilibria of Lennard-Jones
mixtures in a cylindrical pore. A non local density functional
theory
Molecular Physics 72 ,1081 (1991)
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U. Marini Bettolo Marconi, A. Puglisi and A. Vulpiani
La forza dei granelli}
Le Scienze, Agosto 2002
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U. Marini Bettolo Marconi, F.Cecconi and A. Puglisi
Simple Models for compartmentalized sand}
``Traffic and Granular flow 03'' S.P. Hoogendoorn, S.Luding, P.H. Bovy,
M. Schreckenberg, D.E. Wolf Editors, Springer 2005, p. 579.
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