54 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- University of LisbonPT16 papers
- Centro de Matematica Aplicada à Previsão e Decisão EconómicaPT10 papers
- Universidade Técnica de LisboaPT8 papers
- Instituto Superior TécnicoPT6 papers
- Centro de MatemáticaPT4 papers
- Universidade do PortoPT4 papers
- Instituto de TelecomunicaçõesPT3 papers
- Google (United States)US2 papers
- Grupo de Física MatemáticaPT2 papers
- Instituto de Plasmas e Fusão NuclearPT2 papers
- Bielefeld UniversityDE1 paper
- Centre de Physique ThéoriqueFR1 paper
23 papers
Scaling Behavior of Public Procurement Activity
António Curado, Bruno Damásio, Sara Encarnação +2
Public procurement refers to the purchase by public sector entities, such as government departments or local authorities, of Services, Goods, or Works. It accounts for a significan…
Comprehensive Review of Deep Reinforcement Learning Methods and Applications in Economics
Amir Mosavi, Pedram Ghamisi, Yaser Faghan +1
The popularity of deep reinforcement learning (DRL) methods in economics have been exponentially increased. DRL through a wide range of capabilities from reinforcement learning (RL…
On the product formula and convolution associated with the index Whittaker transform
Rúben Sousa, Manuel Guerra, Semyon Yakubovich
We deduce a product formula for the Whittaker function whose kernel does not depend on the second parameter. Making use of this formula, we define the positivity-preserving con…
Scattering theory for the Schrödinger-Debye System
Simão Correia, Filipe Oliveira
We study the Schrödinger-Debye system over iu_t+\frac 12Δu=uv,\quad μv_t+v=λ|u|^2 and establish the global existence and scattering of small solutions for initial da…
The Topology of Inter-industry Relations from the Portuguese National Accounts
Tanya Araújo, Rui Faustino
In last years, the Portuguese economy has gone through a severe adjustment process, affecting almost all industrial sectors, the building blocks of economic structures. Research on…
Barrier Option Pricing under the 2-Hypergeometric Stochastic Volatility Model
Rúben Sousa, Ana Bela Cruzeiro, Manuel Guerra
We investigate the pricing of financial options under the 2-hypergeometric stochastic volatility model. This is an analytically tractable model that reproduces the volatility smile…
The specific shapes of gender imbalance in scientific authorships: a network approach
Tanya Araújo, Elsa Fontainha
Gender differences in collaborative research have received little attention when compared with the growing importance that women hold in academia and research. Unsurprisingly, most…
The Topology of African Exports: emerging patterns on spanning trees
Tanya Araújo, M. Ennes Ferreira
This paper is a contribution to interweaving two lines of research that have progressed in separate ways: network analyses of international trade and the literature on African trad…
Minimising the heat dissipation of quantum information erasure
M. Hamed Mohammady, Masoud Mohseni, Yasser Omar
Quantum state engineering and quantum computation rely on information erasure procedures that, up to some fidelity, prepare a quantum object in a pure state. Such processes occur w…
Asymptotic Poincaré Maps along the edges of Polytopes
Hassan Najafi Alishah, Pedro Duarte, Telmo Peixe
For a class of flows on polytopes, including many examples from Evolutionary Game Theory, we describe a piecewise linear model which encapsulates the asymptotic dynamics along the…
Ergodicity of polygonal slap maps
Gianluigi Del Magno, João Lopes Dias, Pedro Duarte +1
Polygonal slap maps are piecewise affine expanding maps of the interval obtained by projecting the sides of a polygon along their normals onto the perimeter of the polygon. These m…
Disorder-assisted quantum transport in suboptimal decoherence regimes
Leonardo Novo, Masoud Mohseni, Yasser Omar
We investigate quantum transport in binary tree structures and in hypercubes for the disordered Frenkel-exciton Hamiltonian under pure dephasing noise. We compute the energy transp…
Dissipative outer billiards: a case study
Gianluigi Del Magno, José Pedro Gaivão, Eugene Gutkin
We study dissipative polygonal outer billiards, i.e. outer billiards about convex polygons with a contractive reflection law. We prove that dissipative outer billiards about any tr…
A new proof of the Herman-Avila-Bochi formula for Lyapunov exponents of SL(2,R)-cocycles
Alexandre T. Baraviera, Joao Lopes Dias, Pedro Duarte
We study the geometry of the action of SL(2,R) on the projective line in order to present a new and simpler proof of the Herman-Avila-Bochi formula. This formula gives the average…
Entanglement Generation by a Three-Dimensional Qubit Scattering: Concurrence vs. Path (In)Distinguishability
Yuichiro Hida, Hiromichi Nakazato, Kazuya Yuasa +1
A scheme for generating an entangled state in a two spin-1/2 system by means of a spin-dependent potential scattering of another qubit is presented and analyzed in three dimensions…
Hamiltonian elliptic dynamics on symplectic 4-manifolds
Mario Bessa, Joao Lopes Dias
We consider C2 Hamiltonian functions on compact 4-dimensional symplectic manifolds to study elliptic dynamics of the Hamiltonian flow, namely the so-called Newhouse dichotomy. We s…
Generic dynamics of 4-dimensional C2 Hamiltonian systems
Mario Bessa, Joao Lopes Dias
We study the dynamical behaviour of Hamiltonian flows defined on 4-dimensional compact symplectic manifolds. We find the existence of a C2-residual set of Hamiltonians for which ev…
Indistinguishable Particles in Quantum Mechanics: An Introduction
Y. Omar
In this article, we discuss the identity and indistinguishability of quantum systems and the consequent need to introduce an extra postulate in Quantum Mechanics to correctly descr…
Multidimensional continued fractions, dynamical renormalization and KAM theory
K Khanin, J Lopes-Dias, J Marklof
The disadvantage of `traditional' multidimensional continued fraction algorithms is that it is not known whether they provide simultaneous rational approximations for generic vecto…
The Geometry of Crashes - A Measure of the Dynamics of Stock Market Crises
Tanya Araújo, Francisco Louçã
This paper investigates the dynamics of stocks in the S&P500 index for the last 30 years. Using a stochastic geometry technique, we investigate the evolution of the market space an…
Reconstructing an economic space from a market metric
R. Vilela Mendes, Tanya Araújo, Francisco Louçã
Using a metric related to the returns correlation, a method is proposed to reconstruct an economic space from the market data. A reduced subspace, associated to the systematic stru…
A dynamical characterization of the small world phase
Tanya Araujo, R. Vilela Mendes, João Seixas
Small-world (SW) networks have been identified in many different fields. Topological coefficients like the clustering coefficient and the characteristic path length have been used…
A process-reconstruction analysis of market fluctuations
R. Vilela Mendes, R. Lima, T. Araujo
The statistical properties of a stochastic process may be described (1)by the expectation values of the observables, (2)by the probability distribution functions or (3)by probabili…