Do Three Dimensions tell us Anything about a Theory of Everything? (2009)
Alexandre, Jean, Ellis, John, Mavromatos, Nikolaos E
It has been conjectured that four-dimensional N=8 supergravity may provide a suitable framework for a `Theory of Everything', if its composite SU(8) gauge fields become dynamical. We point out that...
Do Three Dimensions tell us Anything about a Theory of Everything? (2009)
Alexandre, Jean, Ellis, John, Mavromatos, Nikolaos E.
It has been conjectured that four-dimensional N=8 supergravity may provide a suitable framework for a `Theory of Everything', if its composite SU(8) gauge fields become dynamical. We point out that...
Lorentz Invariance Violation from String Theory (2007)
In this brief, and by no means complete, review I discuss situations in string theory, in which Lorentz Invariance Violation may occur in a way consistent with world-sheet conformal invariance,...
LHC Physics and Cosmology (2007)
In these Lectures I review possible constraints on particle physics models, obtained by means of combining the results of collider measurements with astrophysical data. I emphasize the...
Observational Evidence for Negative-Energy Dust in Late-Times Cosmology (2007)
Mavromatos, Nikolaos E., Mitsou, Vasiliki A.
We perform fits of unconventional dark energy models to the available data from high-redshift supernovae, distant galaxies and baryon oscillations. The models are based either on brane cosmologies or...
CPT and Decoherence in Quantum Gravity (2007)
In this review, I first discuss briefly some theoretical motivations for potential Lorentz Violation and deviation from ordinary quantum mechanical behavior (decoherence) of field theoretic systems...
Can strings live in four dimensions? (2007)
Alexandre, Jean, Mavromatos, Nikolaos E.
Using a novel, non-perturbative, time-dependent string configuration derived in [1], we present here an argument which selects new critical dimensions for the target space time of a bosonic sigma...
Ellis, John R., Mavromatos, Nikolaos E., Mitsou, Vasiliki A., Nanopoulos, Dimitri V.
14 pages, 5 figures.-- PACS nrs.: 98.80.Es; 95.36.+x; 98.65.Dx.-- ISI Article Identifier: 000244403100010.-- ArXiv pre-print available at: http://arxiv.org/abs/astro-ph/0604272
Probing Models of Quantum Decoherence in Particle Physics and Cosmology (2006)
Mavromatos, Nikolaos E., Sarkar, Sarben
In this review we first discuss the string theoretical motivations for induced decoherence and deviations from ordinary quantum-mechanical behaviour; this leads to intrinsic CPT violation in the...
Relaxation dark energy in non-critical string cosmologies and astrophysical data (2006)
Mavromatos, Nikolaos E., Mitsou, Vasiliki A.
In this talk we review briefly the basic features of non-critical (dissipative) String Cosmologies, and we confront some of these models with supernova data. We pay particular attention to the...
Non-Perturbative Formulation of Non-Critical String Models (2006)
Alexandre, J, Ellis, Jonathan Richard, Mavromatos, Nikolaos E
We apply to non-critical bosonic Liouville string models, characterized by a central-charge deficit Q, a new non-perturbative renormalization-group technique based on a functional method for...
Non-Perturbative Formulation of Non-Critical String Models (2006)
Alexandre, Jean, Ellis, John, Mavromatos, Nikolaos E.
We apply to non-critical bosonic Liouville string models, characterized by a central-charge deficit Q, a new non-perturbative renormalization-group technique based on a functional method for...
Non-Perturbative Formulation of Time-Dependent String Solutions (2006)
Alexandre, J, Ellis, Jonathan Richard, Mavromatos, Nikolaos E
We formulate here a new world-sheet renormalization-group technique for the bosonic string, which is non-perturbative in the Regge slope alpha' and based on a functional method for controlling the...
Non-Perturbative Formulation of Time-Dependent String Solutions (2006)
Alexandre, Jean, Ellis, John, Mavromatos, Nikolaos E.
We formulate here a new world-sheet renormalization-group technique for the bosonic string, which is non-perturbative in the Regge slope alpha' and based on a functional method for controlling the...
CPT and Quantum Mechanics Tests with Kaons (2006)
Bernabeu, José, Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Papavassiliou, J
In this review we first discuss the theoretical motivations for possible CPT violation and deviations from ordinary quantum-mechanical behavior of field-theoretic systems in the context of an...
Confronting Dark Energy Models with Astrophysical Data (2006)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Mitsou, V A, Nanopoulos, Dimitri V
We discuss fits of cosmological dark energy models to the available data on high-redshift supernovae and baryon oscillations. We consider a conventional model with Cold Dark Matter and a cosmological...
Robust Limits on Lorentz Violation from Gamma-Ray Bursts (2005)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sakharov, Alexander S, Sarkisyan-Grinbaum, E
We constrain the possibility of a non-trivial refractive index in free space corresponding to an energy-dependent velocity of light: c(E) \simeq c_0 (1 - E/M), where M is a mass scale that might...
Liouville Cosmology at Zero and Finite Temperatures (2005)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Westmuckett, M
We discuss cosmology in the context of Liouville strings, characterized by a central-charge deficit Q^2, in which target time is identified with (the world-sheet zero mode of the) Liouville field:...
Towards Experimental Tests of Quantum Effects in Cytoskeletal Proteins (2005)
Mershin, Andreas, Sanabria, Hugo, Miller, John H., Nawarathna, Dharmakeerthna, Skoulakis, Efthimios M. C., Mavromatos, Nikolaos E., ...
It has become increasingly evident that fabrication of novel biomaterials through molecular self-assembly is going to play a significant role in material science and possibly the information...
The String Coupling Accelerates the Expansion of the Universe (2005)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Generic cosmological models in non-critical string theory have a time-dependent dilaton background at a late epoch. The cosmological deceleration parameter Q_0 is given by the square of the string...
The String Coupling Accelerates the Expansion of the Universe (2005)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Generic cosmological models in non-critical string theory have a time-dependent dilaton background at a late epoch. The cosmological deceleration parameter Q_0 is given by the square of the string...
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Liouville string theory is a natural framework for discussing the non-equilibrium evolution of the Universe. It enables non-critical strings to be treated in mathematically consistent manner, in...
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Liouville string theory is a natural framework for discussing the non-equilibrium evolution of the Universe. It enables non-critical strings to be treated in mathematically consistent manner, in...
Potentials between D-Branes in a Supersymmetric Model of Space-Time Foam (2005)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Westmuckett, M
We study a supersymmetric model of space-time foam with two stacks each of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that...
Potentials between D-Branes in a Supersymmetric Model of Space-Time Foam (2005)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Westmuckett, M
We study a supersymmetric model of space-time foam with two stacks each of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that...
Potentials between D-Branes in a Supersymmetric Model of Space-Time Foam (2005)
Ellis, John, Mavromatos, Nikolaos E., Westmuckett, Michael
We study a supersymmetric model of space-time foam with two stacks each of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that...
Cosmic Acceleration and the String Coupling (2004)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
In the context of a cosmological string model describing the propagation of strings in a time-dependent Robertson-Walker background space-time, we show that the asymptotic acceleration of the...
Brany Liouville Inflation (2004)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sakharov, A
We present a specific model for cosmological inflation driven by the Liouville field in a non-critical supersymmetric string framework, in which the departure from criticality is due to open strings...
A supersymmetric D-brane Model of Space-Time Foam (2004)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Westmuckett, Michael
We present a supersymmetric model of space-time foam with two stacks of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that represent...
A supersymmetric D-brane Model of Space-Time Foam (2004)
Ellis, John, Mavromatos, Nikolaos E., Westmuckett, Michael
We present a supersymmetric model of space-time foam with two stacks of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that represent...
Space-Time Foam may Violate the Principle of Equivalence (2003)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sakharov, Alexander S
The interactions of different particle species with the foamy space-time fluctuations expected in quantum gravity theories may not be universal, in which case different types of energetic particles...
Space-Time Foam may Violate the Principle of Equivalence (2003)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sakharov, Alexander S
The interactions of different particle species with the foamy space-time fluctuations expected in quantum gravity theories may not be universal, in which case different types of energetic particles...
I discuss various ways in which CPT symmetry may be violated, and their phenomenology in current or immediate future experimental facilities, both terrestrial and astrophysical. Specifically, I...
Synchrotron Radiation and Quantum Gravity (2003)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sakharov, A
Photons may evade a synchrotron radiation constraint on quantum gravity by violating the equivalence principle.
Synchrotron Radiation from the Crab Nebula Discriminates between Models of Space-Time Foam (2003)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Sakharov, A
It has been argued by Jacobson, Liberati and Mattingly that synchrotron radiation from the Crab Nebula imposes a stringent constraint on any modification of the dispersion relations of the electron...
Theoretical and Phenomenological Aspects of CPT Violation (2003)
I review briefly various models and ways of Quantum-Gravity induced CPT violation, and discuss in some detail their phenomenology, in particular precision CPT tests in neutral mesons, and...
Quantum-Gravity Analysis of Gamma-Ray Bursts using Wavelets (2002)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sakharov, Alexander S
In some models of quantum gravity, space-time is thought to have a foamy structure with non-trivial optical properties. We probe the possibility that photons propagating in vacuum may exhibit a...
Vacuum Energy, Cosmological Supersymmetry Breaking and Inflation from Colliding Brane Worlds (2002)
In the context of colliding brane worlds I discuss a toy cosmological model, developed in collaboration with E. Gravanis, which arguably produces inflation and a relaxing to zero cosmological...
Vacuum Energy, Cosmological Supersymmetry Breaking and Inflation from Colliding Brane Worlds (2002)
In the context of colliding brane worlds I discuss a toy cosmological model, developed in collaboration with E. Gravanis, which arguably produces inflation and a relaxing to zero cosmological...
Impact of Low-Energy Constraints on Lorentz Violation (2002)
Ellis, Jonathan Richard, Gravanis, E, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We extend previous analyses of the violation of Lorentz invariance induced in a non-critical string model of quantum space-time foam, discussing the propagation of low-energy particles through a...
Induced N=2 composite supersymmetry in 2+1 dimensions (2002)
Alexandre, J, Mavromatos, Nikolaos E, Sarkar, S
Starting from N=1 scalar supermultiplets in 2+1 dimensions, we build explicitly the composite superpartners which define a N=2 superalgebra induced by the initial N=1 supersymmetry. The occurrence of...
Valleys in String Foam Suppress Quantum Coherence (2002)
Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Ellis, Jonathan Richard
We exhibit string contributions to the $\nd{S}$ matrix relating in- and out- state density matrices that do not factorize as a product of $S$ and $S^\dagger$ matrices. They are associated with valley...
A String Derivation of the $\nd{S}$ matrix (2002)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We show that, in string theory, as a result of the $W_{\infty}$-symmetries that preserve quantum coherence in the {\it full} string theory by coupling different mass levels, transitions between...
A String Derivation of the $\nd{S}$ matrix (2002)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We show that, in string theory, as a result of the $W_{\infty}$-symmetries that preserve quantum coherence in the {\it full} string theory by coupling different mass levels, transitions between...
Measuring the $W$-hair of String Black Holes (2002)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We have argued previously that the infinitely many gauge symmetries of string theory provide an infinite set of conserved (gauge) quantum numbers ($W$-hair) which characterise black hole states and...
The Origin of Space-Time as $W$ Symmetry Breaking in String Theory (2002)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Physics in the neighbourhood of a space-time metric singularity is described by a world-sheet topological gauge field theory which can be represented as a twisted $N=2$ superconformal Wess-Zumino...
Acceleration of the Universe in Type-0 Non-Critical Strings (2002)
I review cosmology within the framework of type-0 non-critical strings, proposed in collaboration with G. Diamandis, B. Georgalas, E. Papantonopoulos and I. Pappa. The instabilities of the tachyonic...
Acceleration of the Universe in Type-0 Non-Critical Strings: a Review (2002)
I review cosmology within the framework of type-0 non-critical strings, proposed in collaboration with G. Diamandis, B. Georgalas, E. Papantonopoulos and I. Pappa. The instabilities of the tachyonic...
Noncritical Liouville string escapes constraints on generic models of quantum gravity (2001)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
It has recently been pointed out that generic models of quantum gravity must contend with severe phenomenological constraints imposed by gravitational Cerenkov radiation, neutrino oscillations and...
Alexandre, J, Farakos, K, Koutsoumbas, G, Mavromatos, Nikolaos E
We consider magnetic catalysis in a field-theoretic system of (3+1)-dimensional Dirac fermions with anisotropic kinetic term. By placing the system in a strong external magnetic field, we examine...
String Theory and an Accelerating Universe (2001)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
An accelerating Universe can be accommodated naturally within non-critical string theory, in which scattering is described by a superscattering matrix \$ that does not factorize as a product of $S$-...
Space-time foam effects on particle interactions and the Greisen-Zatsepin-Kuzmin cutoff (2000)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Modelling space-time foam using a non-critical Liouville-string model for the quantum fluctuations of D branes with recoil, we discuss the issues of momentum and energy conservation in particle...
A Novel Mass Hierarchy and Discrete Excitation Spectra from Quantum-Fluctuating D-branes (2000)
Leontaris, George K, Mavromatos, Nikolaos E
We elaborate further on a recently proposed scenario for generating a mass hierarchy through quantum fluctuations of a single D3 brane, which represents our world embedded in a bulk five-dimensional...
Cell Microtubules as Cavities: Quantum Coherence and Energy Transfer? (2000)
A model is presented for dissipationless energy transfer in cell microtubules due to quantum coherent states. The model is based on conjectured (hydrated) ferroelectric properties of microtubular...
Testing A (Stringy) Model of Quantum Gravity (2000)
I discuss a specific model of space-time foam, inspired by the modern non-perturbative approach to string theory (D-branes). The model views our world as a three brane, intersecting with D-particles...
Testing A (Stringy) Model of Quantum Gravity (2000)
I discuss a specific model of space-time foam, inspired by the modern non-perturbative approach to string theory (D-branes). The model views our world as a three brane, intersecting with D-particles...
String-Inspired Higher-Curvature Terms and the Randall-Sundrum Scenario (2000)
Mavromatos, Nikolaos E, Rizos, J
We consider the O(a') string effective action, with Gauss-Bonnet curvature-squared and forth-order dilaton-derivative terms, which is derived by a matching procedure with string amplitudes in five...
How Large are Dissipative Effects in Non-Critical Liouville String Theory? (2000)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
In the context of non-critical Liouville strings, we clarify why we expect non-quantum-mechanical dissipative effects to be of order E^2/M_P, where E is a typical energy scale of the probe, and M_P...
Nodal Liquids and Duality (2000)
Mavromatos, Nikolaos E, Sarkar, S
Using a SU(2)x U(1) gauge theory for a t-J model around a node of the Fermi surface, we discuss patterns of dynamical symmetry breaking, which may lead to a pseudogap phase and to the appearance of...
Dynamical Formation of Horizons in Recoiling D Branes (2000)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
A toy calculation of string/D-particle interactions within a world-sheet approach indicates that quantum recoil effects - reflecting the gravitational back-reaction on space-time foam due to the...
D-particle Recoil Space Times and "Glueball" Masses (2000)
Mavromatos, Nikolaos E, Winstanley, E
We discuss the properties of matter in a D-dimensional anti-de-Sitter-type space time induced dynamically by the recoil of a very heavy D(irichlet)-particle defect embedded in it. The particular form...
Is Nothing Sacred? Vacuum Energy, Supersymmetry and Lorentz Breaking from Recoiling D branes (2000)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Classical superstring vacua have zero vacuum energy and are supersymmetric and Lorentz-invariant. We argue that all these properties may be destroyed when quantum aspects of the interactions between...
The Quest for Quantum Gravity: Testing Times for Theories? (2000)
I discuss some theoretical ideas concerning the representation of quantum gravity as a Lorentz-symmetry-violating `medium' with non-trivial optical properties, which include a refractive index in...
A mass hierarchy from recoiling D branes (1999)
Leontaris, George K, Mavromatos, Nikolaos E
Using conformal field theory methods we construct a metric that describes the distortion of space-time surrounding a D(irichlet)-brane (solitonic) defect after being struck by another D-brane. By...
Gravitational-recoil effects on fermion propagation in space-time foam (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Volkov, G
Motivated by the possible experimental opportunities to test quantum gravity via its effects on high-energy neutrinos propagating through space-time foam, we discuss how to incorporate spin...
Probing Models of Quantum Space-Time Foam (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We review the possibility that quantum fluctuations in the structure of space-time at the Planck scale might be subject to experimental probes. We study the effects of space-time foam in an approach...
Non-linear Schrödinger Dynamics of Matrix D-branes (1999)
Mavromatos, Nikolaos E, Szabó, R J
We formulate an effective Schroedinger wave equation describing the quantum dynamics of a system of D0-branes by applying the Wilson renormalization group equation to the worldsheet partition...
Logarithmic Operators Fold D branes into $AdS_{3}$ (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Winstanley, E
We use logarithmic conformal field theory techniques to describe recoil effects in the scattering of two Dirichlet branes in D dimensions. In the particular case that a D1 brane strikes a D3 brane...
D-brane recoil and supersymmetry breaking as a relaxation process (1999)
Campbell-Smith, A, Mavromatos, Nikolaos E
We propose a new mechanism for the formation of conical singularities on D-branes by means of recoil resulting from scattering of closed string states propagating in the (large) transverse...
Astrophysical Probes of the Constancy of the Velocity of Light (1999)
Ellis, Jonathan Richard, Farakos, K, Mavromatos, Nikolaos E, Mitsou, V A, Nanopoulos, Dimitri V
We discuss possible tests of the constancy of the velocity of light using distant astrophysical sources such as gamma-ray bursters (GRBs), Active Galactic Nuclei (AGNs) and pulsars. This speculative...
Light-Cone Broadening and TeV Scale Extra Dimensions (1999)
Campbell-Smith, A, Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We examine the effect of light--cone broadening induced by quantum--gravity foam in the context of theories with ``large'' extra dimensions stretching between two parallel brane worlds. We consider...
A Microscopic Recoil Model for Light-Cone Fluctuations in Quantum Gravity (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We present a microscopic model for light-cone fluctuations ``in vacuo'', which incorporates a treatment of quantum-gravitational recoil effects induced by energetic particles. Treating defects in...
Gauge Coupling Instability and Dynamical Mass Generation in N=1 Supersymmetric QED(3) (1999)
Campbell-Smith, A, Mavromatos, Nikolaos E, Papavassiliou, J
Using superfield Dyson-Schwinger equations, we compute the infrared dynamics of the semi-amputated full vertex, corresponding to the effective running gauge coupling, in N-flavour {\mathcal N}=1...
Search for Quantum Gravity (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
A satisfactory theory of quantum gravity may necessitate a drastic modification of our perception of space-time, by giving it a foamy structure at distances comparable to the Planck length. It is...
Magnetic catalysis in even-flavor three-dimensional QED (1999)
Farakos, K, Koutsoumbas, G, Mavromatos, Nikolaos E, Momen, A
In this paper, we discuss the role of an external magnetic field on the dynamically generated fermion mass in even-flavor QED in three space-time dimensions. We show that for weak fields this mass...
On dynamical mass generation in three dimensional supersymmetric U(1) gauge field theory (1999)
Campbell-Smith, A, Mavromatos, Nikolaos E
We investigate and contrast the non-perturbative infra red structure of N=1 and N=2 supersymmetric non-compact U(1) gauge field theory in three space-time dimensions with N matter flavours. We study...
Quantum-Gravitational Diffusion and Stochastic Fluctuations in the Velocity of Light (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We argue that quantum-gravitational fluctuations in the space-time background give the vacuum non-trivial optical properties that include diffusion and consequent uncertainties in the arrival times...
Non-linear Dynamics in $QED_{3}$ and Non-trivial Infrared Structure (1999)
Mavromatos, Nikolaos E, Papavassiliou, J
In this work we consider a coupled system of Schwinger-Dyson equations for self-energy and vertex functions in QED_3. Using the concept of a semi-amputated vertex function, we manage to decouple the...
Comments on CP, T and CPT Violation in Neutral Kaon Decays (1999)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E
We comment on CP, T and CPT violation in the light of interesting new data from the CPLEAR and KTeV Collaborations on neutral kaon decay asymmetries. Other recent data from the CPLEAR experiment,...
Tests of the equivalence principle with neutral kaons (1999)
Apostolakis, Alcibiades J, Aslanides, Elie, Backenstoss, Gerhard, Bargassa, P, Behnke, O, Benelli, A, ...
We test the Principle of Equivalence for particles and antiparticles, using CPLEAR data on tagged Pkao and Pkab decays into $pi^+ pi^-$. For the first time, we search for possible annual, monthly and...
On the Thermodynamics of a Gas of AdS Black Holes and the Quark-Hadron Phase Transition (1999)
Ellis, Jonathan Richard, Ghosh, A, Mavromatos, Nikolaos E
We discuss the thermodynamics of a gas of black holes in five-dimensional anti-de-Sitter (AdS) space, showing that they are described by a van der Waals equation of state. Motivated by the Maldacena...
D-branes and the Non-commutative Structure of Quantum Spacetime (1998)
Mavromatos, Nikolaos E, Szabó, R J
A worldsheet approach to the study of non-abelian D-particle dynamics is presented based on viewing matrix-valued D-brane coordinate fields as coupling constants of a deformed sigma-model which...
D-branes and the Non-commutative Structure of Quantum Spacetime (1998)
Mavromatos, Nikolaos E, Szabó, R J
A worldsheet approach to the study of non-abelian D-particle dynamics is presented based on viewing matrix-valued D-brane coordinate fields as coupling constants of a deformed sigma-model which...
Time-Dependent Vacuum Energy Induced by $D$-Particle Recoil (1998)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We consider cosmology in the framework of a `material reference system' of D particles, including the effects of quantum recoil induced by closed-string probe particles. We find a time-dependent...
Sensitivity of Astrophysical Observations to Gravity-Induced Wave Dispersion in Vacuo (1998)
Amelino-Camelia, G, Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sarkar, S
We discuss possible signatures of quantum gravity for the propagation of light, including an energy-dependent velocity (refractive index), dispersion in velocity at a given energy, and birefringence....
Ellis, Jonathan Richard, Mavromatos, Nikolaos E
We present a Liouville-string approach to confinement in four-dimensional gauge theories, which extends previous approaches to include non-conformal theories. We consider Liouville field theory on...
High-Energy QCD as a Topological Field Theory (1998)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E
We propose an identification of the conformal field theory underlying Lipatov's spin-chain model of high-energy scattering in perturbative QCD. It is a twisted N=2 supersymmetric topological field...
A Microscopic Liouville Arrow of Time (1998)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We discuss the treatment of quantum-gravitational fluctuations in the space-time background as an `environment', using the formalism for open quantum-mechanical systems, which leads to a microscopic...
World-Sheet formulation of M theory (1998)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We first review the interpretation of world-sheet defects as $D$ branes described by a critical theory in 11 dimensions, that we interpret as $M$ theory. We then show that $D$-brane recoil induces...
World-Sheet formulation of M theory (1998)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We first review the interpretation of world-sheet defects as $D$ branes described by a critical theory in 11 dimensions, that we interpret as $M$ theory. We then show that $D$-brane recoil induces...
Irreversible Time Flow in a Two-Dimensional Dilaton Black Hole with Matter (1997)
Diamandis, G A, Ellis, Jonathan Richard, Georgalas, B C, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Papantonopoulos, E
We show that an exact solution of two-dimensional dilaton gravity with matter discovered previously exhibits an irreversible temporal flow towards flat space with a vanishing cosmological constant....
Potential Sensitivity of Gamma-Ray Burster Observations to Wave Dispersion in Vacuo (1997)
Amelino-Camelia, G, Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Sarkar, S
The recent confirmation that gamma-ray bursters (GRBs) are indeed at cosmological distances raises the possibility that observations of these could provide interesting constraints on the fundamental...
Decoherent Scattering of Light Particles in a D-Brane Background (1997)
Ellis, Jonathan Richard, Kanti, Panagiota, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Winstanley, E
We discuss the scattering of two light particles in a D-brane background. It is known that, if one light particle strikes the D brane at small impact parameter, quantum recoil effects induce...
Vacuum Fluctuations and Decoherence in Mesoscopic and Microscopic Systems (1997)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We discuss recent experimental evidence of decoherence in a laboratory mesoscopic system in a cavity, from which we draw analogies with the decoherence that we argue is induced by microscopic...
M Theory from World-Sheet Defects in Liouville String (1997)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We have argued previously that black holes may be represented in a D-brane approach by monopole and vortex defects in a sine-Gordon field theory model of Liouville dynamics on the world sheet....
Quantum Decoherence in a D-Foam Background (1997)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Within the general framework of Liouville string theory, we construct a model for quantum D-brane fluctuations in the space-time background through which light closed-string states propagate. The...
On the Space-Time Uncertainty Relations of Liouville Strings and D Branes (1997)
Amelino-Camelia, G, Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Within a Liouville approach to non-critical string theory, we argue for a non-trivial commutation relation between space and time observables, leading to a non-zero space-time uncertainty relation...
D-Brane Recoil Mislays Information (1996)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We discuss the scattering of a light closed-string state off a $D$ brane, taking into account quantum recoil effects on the latter, which are described by a pair of logarithmic operators. The...
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We discuss the possibility that CPT violation may appear as a consequence of microscopic decoherence due to quantum-gravity effects, that we describe using a density-matrix formalism motivated by our...
Distance measurement and wave dispersion in a Liouville-string approach to quantum gravity (1996)
Amelino-Camelia, G, Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Within a Liouville approach to non-critical string theory, we discuss space-time foam effects on the propagation of low-energy particles. We find an induced frequency-dependent dispersion in the...
D-branes from Liouville strings (1996)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We develop quantization aspects of our Liouville approach to non-critical strings, proposing a path-integral formulation of a second quantization of string theory, that incorporates naturally the...
Quantum decoherence in a four-dimensional black hole background (1996)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V, Winstanley, E
We display a logarithmic divergence in the density matrix of a scalar field in the presence of an Einstein-Yang-Mills black hole in four dimensions. This divergence is related to a previously-found...
Dilatonic black holes in higher curvature string gravity (1995)
Kanti, Panagiota, Mavromatos, Nikolaos E, Rizos, J, Tamvakis, Kyriakos, Winstanley, E
We give analytical arguments and demonstrate numerically the existence of black hole solutions of the 4D Effective Superstring Action in the presence of Gauss-Bonnet quadratic curvature terms. The...
Test of CPT symmetry and quantum mechanics with experimental data from CPLEAR (1995)
Adler, R, Angelopoulos, Angelos, Apostolakis, Alcibiades J, Aslanides, Elie, Backenstoss, Gerhard, Bee, C P, ...
We use fits to recent published CPLEAR data on neutral kaon decays to \pi^+\pi^- and \pi e\nu to constrain the CPT--violation parameters appearing in a formulation of the neutral kaon system as an...
Experimental tests of CPT symmetry and quantum mechanics at CPLEAR (1995)
Mavromatos, Nikolaos E, Ellis, Jonathan Richard, López, J L, Nanopoulos, Dimitri V, Adler, R, Alhalel, T, ...
We review a phenomenological parametrization of an open quantum-mechanical formalism for CPT violation in the neutral kaon system, and constrain the parameters using fits to recent CPLEAR data.
Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Microtubule (MT) networks, subneural paracrystalline cytosceletal structures, seem to play a fundamental role in the neurons. We cast here the complicated MT dynamics in the form of a 1+1-dimensional...
Precision tests of CPT symmetry and quantum mechanics in the neutral kaon system (1995)
Ellis, Jonathan Richard, López, J L, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We present a systematic phenomenological analysis of the tests of CPT symmetry that are possible within an {\em open} quantum-mechanical description of the neutral kaon system that is motivated by...
A string scenario for inflationary cosmology (1995)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We describe a scenario for inflation in the framework of non-critical string theory, which does not employ an inflaton field. There is an exponential expansion of the volume of the Universe, induced...
Some physical aspects of Liouville string dynamics (1994)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We discuss some physical aspects of our Liouville approach to non-critical strings, including the emergence of a microscopic arrow of time, effective field theories as classical ``pointer'' states in...
A non-critical string approach to black holes, time and quantum dynamics (1994)
Ellis, Jonathan Richard, Nanopoulos, Dimitri V, Mavromatos, Nikolaos E
We review our approach to time and quantum dynamics based on non-critical string theory, developing its relationship to previous work on non-equilibrium quantum statistical mechanics and the...
A non-critical string approach to black holes, time and quantum dynamics (1994)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We review our approach to time and quantum dynamics based on non-critical string theory, developing its relationship to previous work on non-equilibrium quantum statistical mechanics and the...
A Liouville string approach to microscopic time and cosmology (1993)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
In the non-critical string framework that we have proposed recently, the time $t$ is identified with a dynamical local renormalization group scale, the Liouville mode, and behaves as a statistical...
Valleys in string foam suppress quantum coherence (1993)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
A string derivation of the super S matrix (1993)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
CPT violation in string-modified quantum mechanics and the neutral kaon system (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We show that $CPT$ is in general violated in a non-quantum-mechanical way in the effective low-energy theory derived from string theory, as a result of apparent world-sheet charge non-conservation...
Time-dependent perturbations in two-dimensional string black holes (1992)
Diamandis, G A, Georgalas, B C, Maintas, X N, Mavromatos, Nikolaos E
We discuss time-dependent perturbations (induced by matter fields) of a black-hole background in tree-level two-dimensional string theory. We analyse the linearized case and show the possibility of...
The string universe: high T$_{c}$ superconductor or quantum Hall conductor? (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Our answer is the latter. Space-time singularities, including the initial one, are described by world-sheet topological Abelian gauge theories with a Chern-Simons term. Their effective $N=2$...
String theory modifies quantum mechanics (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We argue that the light particles in string theory obey an effective quantum mechanics modified by the inclusion of a quantum-gravitational friction term, induced by unavoidable couplings to...
Testing quantum mechanics in the neutral kaon system (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
The neutral kaon system is a sensitive probe of quantum mechanics. We revive a parametrization of non-quantum-mechanical effects that is motivated by considerations of the nature of space-time foam,...
Phase structure of QED$_{3}$ at finite temperature (1992)
Aitchison, Ian Johnston Rhind, Dorey, N, Klein-Kreisler, M, Mavromatos, Nikolaos E
Dynamical symmetry breaking in three-dimensional QED with N fermion flavours is considered at finite temperature, in the large $N$ approximation. Using an approximate treatment of the Schwinger-Dyson...
World-sheet duality, space-time foam, and the quantum fate of a stringy black hole (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We interpret Minkowski black holes as world-sheet {\it spikes } which are related by world-sheet { \it duality} to {\it vortices } that correspond to Euclidean black holes. These world-sheet defects...
The origin of space-time as W symmetry breaking in string theory (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
On the W-hair of string black holes and the singularity problem (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We argue that the infinitely many gauge symmetries of string theory provide an infinite set of conserved (gauge) quantum numbers (W-hair) which characterise black hole states and maintain quantum...
Measuring the W-hair of string black holes (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Quantum Mechanics and Black Holes in Four-Dimensional String Theory (1992)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
In previous papers we have shown how strings in a two-dimensional target space reconcile quantum mechanics with general relativity, thanks to an infinite set of conserved quantum numbers, ``W-hair'',...
On the Evaporation of Black Holes in String Theory (1991)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
We show that, in string theory, the quantum evaporation and decay of black holes in two-dimensional target space is related to imaginary parts in higher-genus string amplitudes. These arise from the...
On the connection between quantum mechanics and the geometry of two-dimensional strings (1991)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
On the basis of an area-preserving symmetry in the phase space of a one-dimensional matrix model - believed to describe two-dimensional string theory in a black-hole background which also allows for...
Quantum coherence and two-dimensional black holes (1991)
Ellis, Jonathan Richard, Mavromatos, Nikolaos E, Nanopoulos, Dimitri V
Aspects of the low energy limit of string theories / (1987)
BLDSC reference no.: D76587.