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Introduction
Gérard Gremaud received his diploma in physics engineering in 1974 and his PhD in 1981. From this date, he became responsible for research at EPFL. In 2005, he obtained the title of Professor of EPFL. In 2011, he has been awarded the Zener medal. Since 2012, he is honorary professor of EPFL.
Research: dislocation dynamics, structural phase transitions, mechanical and tribological properties at nanoscale, mechanical properties of vibrated granular materials, mechanical spectroscopy, cosmology.
Publications
Publications (210)
In this brief communication, we summarize an original and new approach of the Universe, which considers that the Universe could be a finite, elastic and massive solid that would move and deform in an infinite absolute vacuum. In this a priori strange concept, it is supposed that the Universe is a lattice of simple cubic crystalline structure, whose...
In the theory of the "cosmological lattice" presented in this book, the problem of unifying physical theories and the search for a Theory of the Whole is treated in a radically different way from other approaches in the literature. Instead of trying to build a unified theory by tinkering with a collection of existing theories, making them more and...
In the theory of the "cosmological lattice" presented in this book, the problem of unifying physical theories and the search for a Theory of the Whole is treated in a radically different way from other approaches in the literature. Instead of trying to build a unified theory by tinkering with a collection of existing theories, making them more and...
Dans la théorie du “réseau cosmologique” qui est présentée dans ce livre, le problème de l’unification des théories physiques et de la recherche d’une Théorie du Tout est traité d’une manière radicalement différente des autres approches de la littérature. Au lieu d’essayer de construire une théorie unifiée en bricolant un assemblage de théories exi...
Dans la théorie du “réseau cosmologique” qui est présentée dans ce livre, le problème de l’unification des théories physiques et de la recherche d’une Théorie du Tout est traité d’une manière radicalement différente des autres approches de la littérature. Au lieu d’essayer de construire une théorie unifiée en bricolant un assemblage de théories exi...
Un des problèmes fondamentaux de la physique moderne est la recherche de la Théorie du Tout, capable d'expliquer la nature de l'espace-temps, ce qu'est la matière et comment la matière interagit. Il existe de nombreuses propositions comme la "Grande Unification", la Gravité Quantique, la Gravitation Quantique à Boucles, les Théories de Cordes et de...
One fundamental problem of modern physics is the search for a theory of everything able to explain the nature of space-time, what matter is and how matter interacts. There are various propositions, as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, and M-Theory. However, none of them is able to consistently ex...
Un des problèmes fondamentaux de la physique moderne est la recherche de la Théorie du Tout, capable d'expliquer la nature de l'espace-temps, ce qu'est la matière et comment la matière interagit. Il existe de nombreuses propositions comme la "Grande Unification", la Gravité Quantique, la Gravitation Quantique à Boucles, les Théories de Cordes et de...
One fundamental problem of modern physics is the search for a theory of everything able to explain the nature of space-time, what matter is and how matter interacts. There are various propositions, as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, and M-Theory. However, none of them is able to consistently ex...
Ce papier résume comment une nouvelle approche de l’Univers basée sur l’existence d’un
«éther cristallin», qui a été récemment exposée en détail dans les troisièmes versions de deux livres [1], permet de trouver une explication simple, unifiée et cohérente de l’ensemble des théories de la physique moderne et de l’Univers.
Les concepts de base de ce...
This paper summarizes how a new approach to the Universe based on the existence of a
"crystalline ether", which has recently been detailed in the third versions of two books [1],
makes it possible to find a simple, unified and coherent explanation of all the theories of modern
physics and of the Universe.
The basic concepts of this approach can be...
This paper summarizes how a new approach to the Universe, which has been recently exposed in two books [1], allows to find a simple, unified and coherent explanation of all the theories of modern physics and of the Universe.
The basic concepts of this approach can be summarized as follows: (i) the support of the Universe is a form of "ether" which...
Ce papier résume comment une nouvelle approche de l’Univers, qui a été récemment exposée en détail dans deux livres [1], permet de trouver une explication simple, unifiée et cohérente de l’ensemble des théories de la physique moderne et de l’Univers.
Les concepts de base de cette approche peuvent se résumer de la manière suivante: (i) le support d...
Dans cette brève communication, nous résumons comment une nouvelle approche de l'Univers, qui a été récemment exposée en détail dans deux livres , permet de trouver une explication simple, unifiée et cohérente de l'ensemble des théories de la physique moderne. Les concepts de base de cette approche peuvent se résumer simplement de la manière suivan...
In this short paper, we summarize how a new approach to the Universe, which has recently been detailed in two books, makes it possible to find a simple, unified and coherent explanation of all the theories of modern physics. The basic concepts of this approach can be summarized simply as follows: (i) the support of the Universe is a kind of «ether»...
Dans cette brève communication, nous résumons une approche originale et nouvelle de l'Univers, qui considère que l'Univers pourrait être un solide fini, élastique et massif qui se déplacerait et se déformerait dans un vide absolu infini. Dans ce concept a priori étrange, on suppose que l'Univers est un réseau de structure cristalline cubique simple...
In this brief communication, we summarize an original and new approach of the Universe, which considers that the Universe could be a finite, elastic and massive solid that would move and deform in an infinite absolute vacuum. In this a priori strange concept, it is supposed that the Universe is a lattice of simple cubic crystalline structure, whose...
L’Univers pourrait être un réseau tridimensionnel, élastique et massif, et les composants fondamentaux de la Matière Ordinaire pourraient être des singularités topologiques de ce réseau, à savoir des boucles de dislocation, de désinclinaison et de dispiration. Cette théorie nouvelle permet de déduire l’électromagnétisme, la relativité restreinte, l...
Un des problèmes fondamentaux de la physique moderne est la recherche de la Théorie du Tout, capable d'expliquer la nature de l'espace-temps, ce qu'est la matière et comment la matière interagit. Il existe de nombreuses propositions comme la "Grande Unification", la Gravité Quantique, la Gravitation Quantique à Boucles, les Théories de Cordes et de...
One fundamental problem of modern physics is the search for a theory of everything able to explain the nature of space-time, what matter is and how matter interacts. There are various propositions, as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, and M-Theory. However, none of them is able to consistently ex...
Here, we will find a solution to the second partial equation of Newton with the torus
around a SDL. We will show that there are no static solutions to this equation and
that, as a consequence, we will have to search for a dynamic solution for the gravitational
perturbations of expansion in the immediate vicinity of the loop. This dynamic
solution w...
Intuitively, we can see that Quantum Mechanics (QM) could be linked to the existence
of dynamical solutions of the second partial Newton’s equation of the cosmic
lattice, under the form of temporal fluctuations of the field of expansion, associated
with the topological singularities of the cosmic lattice when it is without longitudinal
waves in the...
In a lattice universe, it is possible to imagine a scenario of cosmological evolution
of the topological singularities which form after the big-bang. This scenario explains
the formation of galaxies, the phenomenon of dark matter of the astro-physicists,
the disappearance of anti-matter from the Universe, the formation of massive black
holes in the...
Here, we will look at the very short distance gravitational interaction between a
twist disclination loop (TL) and an edge dislocation loop (EL) due to the charge of
curvature of the EL and the charge of rotation of the TL and their respective perturbations
to the field of expansion.
We show that this interaction between charges of rotation and cur...
Considering a finite imaginary sphere of a cosmic lattice, we can introduce the
concept of "cosmological evolution" of the lattice, assuming that one injects a certain
amount of kinetic energy inside the lattice. In this case, the lattice has strong
temporal variations of its volume expansion, that can be modeled very simplistically
assuming that v...
Here, we study in detail the gravitational interactions of twist disclination loops (TL),
which will yield a strong analogy with Newtonian gravitation in the far-field but that
will exhibit differences in the near-field. We will also exhibit a dependence of the
constant of gravitation on the volume expansion of the lattice.
Next, we focus on the Ma...
We have shown previously that the perfect lattice presents strong analogies with
the great theories of modern physics, namely the equations of electro-magnetism,
general relativity, special relativity, black holes, cosmology, dark energy and quantum
mechanics, and that we can have 3 types of basic topological loop singularities
which possess respec...
In a perfect cosmic lattice satisfying , all microscopical topological singularities
like dislocation lines and dislocations/disclination loops satisfy Lorentz
transformations based on the transversal wave velocity. As a consequence, a localized
cluster of topological singularities which interact with each other via their rotation
fields is also su...
We apply here the Lorentz transformation to the topological singularities in motion
in order to obtain, in the absolute frame of the lattice, the fields of dynamical distortions
and velocities associated to screw and edge dislocations, localized rotation
charges, twist loops and edge loops moving at relativistic speed. From these fields,
their tota...
We start by showing that we can separate the field of volume expansion from the
other fields in the Newton equation of a cosmic lattice in the case where the
concentration of point defects are constant. Then we use these results to obtain the
Maxwell’s equations of evolution of a lattice in the case where the volume expansion
can be treated as cons...
We introduce a perfect isotropic lattice, which is purely imaginary, and we will call it
the cosmic lattice. The development of its free energy of deformation is expressed
per unit volume, which depends linearly on volume expansion and quadratically on
volume expansion, shear strain and torsional rotation deformations, and allows us
to deduce the N...
One fundamental problem of modern physics is the search for a theory of everything able to explain the nature of space-time, what matter is and how matter interacts. There are various propositions, as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, and M-Theory. However, none of them is able to consistently ex...
Un des problèmes fondamentaux de la physique moderne est la recherche d’une Théorie du Tout capable d’expliquer la nature de l’espace-temps, ce qu’est la matière et comment la matière interagit. Il existe diverses propositions de Théorie du Tout, comme la Grande Unification, la Gravité Quantique, la Gravitation Quantique à Boucles, les Théories de...
I - Eulerian theory of newtonian deformable lattices a - Geometrokinetic equations and distortion tensors b - The three necessary physical principles c - Geometrocompatibility equations and contortion tensors d - Charges associated to topological singularities II - The « cosmic lattice » a - Waves propagation b - Wave rays curvature c - Lattice cos...
I - Eulerian theory of newtonian deformable media II - Application: phenomenologies of usual fluids and solids III - Dislocation and disclination charges IV - Application: elements of dislocation theory in usual solids Conclusion
One fundamental problem of modern physics is the search for a theory of everything able to explain the nature of space-time, what matter is and how matter interacts. There are various propositions, as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, and M-Theory. However, none of them is able to consistently ex...
Un des problèmes fondamentaux de la physique moderne est la recherche d’une Théorie du Tout capable d’expliquer la nature de l’espace-temps, ce qu’est la matière et comment celle-ci interagit. Il existe déjà diverses théories candidates (Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, M-Theory). Cependant, auc...
It is shown that the set of equations known as “Maxwell’s equations” perfectly describe
two very different systems: (1) the usual electromagnetic phenomena in
vacuum or in the matter and (2) the deformation of isotropic solid lattices, containing
topological defects as dislocations and disclinations, in the case of constant
and homogenous expansion...
One fundamental problem of modern physics is the search for a theory of everything able to explain
the nature of space-time, what matter is and how matter interacts. There are various propositions,
as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories,
and M-Theory. However, none of them is able to consistently ex...
In this book, one summarizes autonomously a first book (1) published during year 2013, which lays methodically the foundations of an original approach of the solid lattices deformation using the Euler coordinates, and which introduces in details the concept of tensor dislocation charges and tensor disclination charges within a lattice. This new con...
One fundamental problem of modern physics is the search for a theory of everything able to explain the nature of space-time, what matter is and how matter interacts. There are various propositions, as Grand Unified Theory, Quantum Gravity, Supersymmetry, String and Superstring Theories, and M-Theory. However, none of them is able to consistently ex...
Un des problèmes fondamentaux de la physique moderne est la recherche de la Théorie du Tout capable d'expliquer la nature de l'espace-temps, ce qu'est la matière et comment la matière interagit. Il existe de nombreuses propositions comme la "Grande Unification" , la Gravité Quantique, la Gravitation Quantique à Boucles, et les Théories de Cordes et...
This book would like to show that an eulerian theory of deformation of a newtonian
lattice in an absolute space, using judicious elastic and structural properties of this
lattice, can furnish an investigation frame extremely rich and interesting for physics.
Indeed, it shows very strong and often perfect analogies with all the modern physics
theori...
Illustrated summary in english of the book "Universe and Matter conjectured as a 3-dimensional Lattice with Topological Singularities"
Ce livre est la version 2 d'un essai dont la finalité est de montrer qu’une théorie eulérienne de la déformation d’un réseau newtonien dans un espace absolu, moyennant un choix judicieux des propriétés élastiques et structurales de ce réseau, peut fournir un
cadre d’investigation extrêmement riche et intéressant pour la physique parce
qu’elle fait...
Une des questions les plus fondamentales de la physique moderne est la nature de l’espace-temps. Il
y a de nombreuses théories pour l’expliquer, telles que la théorie de grande unification, la gravité
quantique, la supersymétrie, les théories de cordes et de supercordes, et la théorie-M. Cependant,
aucune de ces théories n’explique ce qu’est la mat...
Ce livre est la version 1 d'un essai dont la finalité est de montrer qu’une théorie eulérienne de la
déformation d’un réseau newtonien dans un espace absolu, moyennant un choix
judicieux des propriétés élastiques et structurales de ce réseau, peut fournir un
cadre d’investigation extrêmement riche et intéressant pour la physique parce
qu’elle fait...
One of the most fundamental questions of modern physics is the nature of
spacetime. There are various propositions on the table, as the grand unified
theory, quantum gravity, supersymmetry, string and superstring theories, and M
theory. However, none of these propositions is able to consistently explain
what matter is and how matter interacts by de...
We present a high precision particle-by-particle 3D reconstruction of granular systems composed of monodispersed spheres (sphere packings); the experimental approach is based on magnetic resonance imaging techniques. Our measurements revealed a strong correlation between the volume defined by the distance to the first nearest neighbor and the long-...
We study the jamming process arising in granular systems subjected to decreasing external vibration, which has features similar to the cooling of glass-forming liquids. We modify the friction between grains and observe that jamming occurs 'more easily' for grains with higher surface roughness. To understand the observed behavior we present a detail...
Cet ouvrage propose une théorie unifiée, originale et novatrice de la déformation des milieux fluides et solides. Les équations fondamentales d’évolution des milieux déformables y sont développées de façon méthodique et rigoureuse, sous forme vectorielle et en coordonnées d’Euler. Elles sont appliquées à la description phénoménologique des fluides...
We propose a new approach to the study of diffusion dynamics in vibrated granular systems. The dynamic of a granular material is mainly defined by dry friction interactions. This type of interaction is difficult to model for a large quantity of particles. In this work, we study a granular system by analyzing the angular position time series of an i...
We investigate the jamming transition observed in vibrated granular systems composed of millimeter size glass beads. When a granular system is submitted to vibrations with decreasing intensity, it evolves in a way similar to glass-forming liquids: from a low viscosity, liquid-like state, it evolves into an amorphous jammed state. This evolution is...
We investigate a vibrated granular system composed of millimeter-size glass beads. When the system is submitted to a perturbation with decreasing intensity, below the fluidization limit, it evolves in a way similar to glass-forming liquids until it reaches an amorphous jammed state. This jamming transition is observed by the means of an immersed os...
The creep of a dislocation on its glide plane is essentially controlled by three different stress fields: the external applied stress, the internal stress field due to a multi-scale hierarchy of different obstacles (the structural defects acting on the dislocation by short- or long-range interactions) and the thermal stress field due to thermal flu...
A traditional photonic-force microscope (PFM) results in huge sets of data, which requires tedious numerical analysis. In this paper, we propose instead an analog signal processor to attain real-time capabilities while retaining the richness of the traditional PFM data. Our system is devoted to intracellular measurements and is fully interactive th...
We consider dislocations as vortices in elastic strain field and show that an ordered system of partial dislocations in faulted martensites is analogous to a system of flux lines (supercurrent vortices) in type-II superconductors. The network of interacting partial dislocations can form vortex matter, whose dynamics is controlled by applied stress...
We describe the latest design of the automated piezoelectric ultrasonic composite oscillator technique, which has traditionally been used for the measurements of elastic and anelastic properties of solids at frequencies of 70-140 kHz in a continuous positive feedback mode. The new equipment features several substantial advantages, as compared to pr...
A number of unusual anelastic phenomena has been observed in the low-temperature non-linear anelasticity of martensitic phases with faulted structure (β′, β′1), typical for binary and ternary Cu-based alloys, when studied at ultrasonic frequencies of around 100 kHz. We suggest to consider interacting and ordered partial dislocations in faulted mart...
An extensive investigation of elastic and anelastic properties, at an ultrasonic frequency of around 100 kHz, of a variety of binary and ternary Cu-based alloys forming faulted martensites evidences the existence of a strong anelastic relaxation over a wide temperature range propagating down to lowest temperatures achieved in experiments of around...
Several ideas of near?field detection of ultrasonic vibrations of the sample surface using atomic force microscopy (AFM) have been developed. Two major techniques are used: contact and nonlinear detection (intermittent contact). Most of the experiments were performed using low?MHz frequencies, meaning that wave propagation can be neglected in thin...
Comparisons between adhesion hysteresis and friction at nanometer and micrometer length scales were investigated experimentally and theoretically. Nanoscale adhesion hysteresis was measured using the ultrasonic force microscopy (UFM) on mica, calcite, and a few metallic samples (Pt, Au, Cu, Zn, Ti, and Fe). Obtained adhesion hysteresis ranged betwe...
Adhesion hysteresis is the difference between the work used on separating two surfaces and the work gained on bringing them back together. Although much effort has been invested into adhesion hysteresis investigations at macroscales and microscales, its measurements at the nanolengths or even molecular lengths are still not easy. In this paper we d...
A nanoscale manipulation system has been designed and built through the integration of a force-feedback haptic device and a commercial atomic force microscope. The force-feedback interaction provides a very intuitive, efficient and reliable way for quick manipulation of nanoscale objects. Unlike other nanomanipulators, ours allows the user to feel...
Correlations between adhesion hysteresis and local friction are theoretically and experimentally investigated. The model is based on the classical theory of adhesional friction, contact mechanics, capillary hysteresis, and nanoscale roughness. Adhesion hysteresis was found to scale with friction through the scaling factor containing a varying ratio...
By means of ultrasonic force microscopy and lateral force microscopy we measure adhesion hysteresis and friction on protein films of bovine serum albumin and concanavalin A at local scales. Our investigations at different relative humidities (less than 5% and at 50% relative humidity) correspond to dehydrated and hydrated states of proteins. We dem...
The first part of this chapter describes local (at the scale of
nanometers) measurements of mechanical properties. It includes detailed
state-of-the-art presentation and in-depth analysis of experimental
techniques, results, and interpretations.
Adhesion hysteresis is defined as the difference of the work necessary for separating two surfaces and gained on bringing them together. It has been demonstrated that it should be closely related to friction [1],[2]. Such correlations are, however, difficult to measure by means of an Atomic Force Microscope (AFM) since typically compliant cantileve...
This chapter describes local measurements and applications of nanoscale mechanical properties. It includes detailed state of the art presentation and in-depth analysis of experimental techniques, results and interpretations.
After a short introduction, the second part of the chapter explores the application of local mechanical spectroscopy using co...
A granular system is weakly vibrated and we observe how it reaches a static configuration when the perturbation intensity is decreased. This behavior is investigated using an immersed torsion oscillator whose angular deflections are analyzed to give information on the granular agitation. The oscillator can thus be seen as a low-frequency “thermomet...
Motivated by recent experiments on the approach to jamming of a weakly forced granular medium using an immersed torsion oscillator [Nature 413 (2001) 407], we propose a simple model which relates the microscopic dynamics to macroscopic rearrangements and accounts for the following experimental facts: (1) the control parameter is the spatial amplitu...
We study the process by which a perturbed granular medium of millimetric-size particles reaches a "frozen" static configuration by decreasing perturbation intensity. The granular system is perturbed by isolated taps or by continuous vibrations. The granular process is observed by an immersed oscillator, which is used as a low-frequency "thermometer...
In this article we further develop local mechanical spectroscopy and extend the frequency range over which it can be used. Using a heterodyne method to measure the deflection of the cantilever enables one to measure the probe vibration at any frequency. Since the detection sensitivity of force gradients follows a f2 dependence, extending the freque...
It has been suggested that a common conceptual framework known as 'jamming' (refs 1 and 2) may be used to classify a wide variety of physical systems; these include granular media, colloidal suspensions and glass-forming liquids, all of which display a critical slowdown in their dynamics before a sudden transition to an amorphous rigid state. Decre...
The quasistatic frequency response of a granular medium is measured by a forced torsion oscillator method, with forcing frequency f(p) in the range 10(-4) Hz to 5 Hz, while weak vibrations at high-frequency f(s), in the range 50 Hz to 200 Hz, are generated by an external shaker. The intensity of vibration Gamma is below the fluidization limit. A lo...
The slow dynamics of a weakly vibrated granular medium is investigated
using a low-frequency forced torsion pendulum method. A loss factor
peak is observed in the pendulum response (or the granular
susceptibility) as a function of the vibration intensity or the
forcing frequency. The position of the peak follows an Arrhenius-like
behaviour and the...
Scanning acoustic microscopy is currently being used routinely for both imaging materials for qualitative examination as well as for measuring elastic properties in localized areas. This paper details the principles of this technique, the origin of the acoustic contrast, and its applications.
The dislocation-point defects (DPDs) interactions which can be understood on the basis of the dislocation string model are discussed. These DPS take place when the kink pair formation on the dislocations, associated with the dislocation-lattice interaction, becomes very easy, at temperatures higher than the temperature of the Bordoni peak in fcc me...
An overview is given of two ultrasonic techniques. One is the Piezoelectric Ultrasonic Composite Oscillator Technique (PUCOT) that is based on an ultrasonic resonant method, and the other is the Acoustic Coupling Technique (ACT) which is based on an ultrasonic pulsed method.
A previous study showed that local spectroscopy of samples can be performed using the Scanning Local-Acceleration Microscope (SLAM). This paper presents simple models that allow to explain the measurement principles and to interpret the experimental results of the SLAM.
Mechanical spectroscopy is a non-destructive technique that is very well suited for studying the dynamics of singularities such as structural defects in solids. It has been successfully applied in solid state physics and materials science for more than fifty years, and the present textbook aims at summarising the state-of-the-art in this field by p...