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Marco A. S. Trindade

Publications and source records attributed to Marco A. S. Trindade.

14 recordsLinked to original sources

Quantum classification and search algorithms using spinorial representations

We propose an algebraic formulation for two distinct quantum algorithms: a quantum classification algorithm and a quantum search algorithm with a non-uniform initial distribution, both based on Clifford algebras and spinorial representations. In the classification algorithm, we exploit properties of spinorial representations to construct orthogonal quantum states associated with different classes, allowing the identification of an item's class through the evaluation of expectation values of operators derived from the generators of the Clifford algebra. In the quantum search algorithm, we consider a database with prior information in which the oracle is implemented directly using generators of the Clifford algebra, simplifying its realization. The proposed approach provides a unified algebraic description for both algorithms, employing spinorial representations in the construction of quantum states and operators. Computational implementations are presented.

quant-ph↗

Information-theoretic structure for the Tsallis q-entropy in statistical physics

In this work, we derive information-theoretic properties for a modified Tsallis entropy, hereinafter referred to as q-entropy. We introduce the notions of joint q-entropy, conditional q-entropy, relative q-entropy, conditional mutual q-information, and establish several inequalities analogous to those of classical information theory. Within the context of Markov chains, these results are employed to prove a version of the second law of thermodynamics. Furthermore, we investigate the maximum entropy method in this setting. Finally, we prove a Tsallis version of the Shannon-McMillan-Breiman theorem and discuss the implications of these results in nonextensive statistical physics.

math-ph↗

Poisson superalgebras and quantization

In this work, we find the Poisson superalgebras related to schemes of quantization. Initially, we consider the Dirac superbracket in the context of the quantization of constrained systems. Next, we show the existence of a Poisson supermanifold in the scenario of quantization deformation.

math-ph↗

Clifford Algebras, Quantum Neural Networks and Generalized Quantum Fourier Transform

We propose models of quantum neural networks through Clifford algebras, which are capable of capturing geometric features of systems and to produce entanglement. Due to their representations in terms of Pauli matrices, the Clifford algebras are the natural framework for multidimensional data analysis in a quantum setting. Implementation of activation functions and unitary learning rules are discussed. In this scheme, we also provide an algebraic generalization of the quantum Fourier transform containing additional parameters that allow performing quantum machine learning. Furthermore, some interesting properties of the generalized quantum Fourier transform have been proved.

quant-ph↗

Thermal Lie Superalgebras

We derive a general formulation for thermal Lie superalgebras motivated by thermofield dynamics formalism (TFD). Particularly, we construct the thermal Poincaré superalgebras. The operators in TFD are defined through the doubling of the degrees of freedom of the system and it can be related to Hopf algebras. In this way we explore the notion of quantum group associated with these superalgebras and we show the non-commutativity in this thermal scenario. Furthermore, the thermal M-superalgebra is also derived from TFD prescription.

hep-th↗

Negativity of the Wigner function and thermal effects of Bell-Cat states

We applied the Thermofield Dynamics formalism to analyze how the non-classical properties of the Bell-Cat states are influenced by a gradual change of temperature values, in a thermal equilibrium system. To this purpose we calculate the thermal Wigner functions for these states, whose negative volume is associated with non-classical properties, and we evaluate how these non-classical features vary with temperature. Our results indicate that these properties are almost absent for temperatures of around $2\mathrm{K}$.

quant-ph↗

Clifford algebras, algebraic spinors, quantum information and applications

We give an algebraic formulation based on Clifford algebras and algebraic spinors for quantum information. In this context, logic gates and concepts such as chirality, charge conjugation, parity and time reversal are introduced and explored in connection with states of qubits. Supersymmetry and M-superalgebra are also analysed with our formalism. Specifically we use extensively the algebras $Cl_{3,0}$ and $Cl_{1,3}$ as well as tensor products of Clifford algebras.

quant-ph↗

Majorana fermions, supersymmetry and thermofield dynamics

In this work we show the existence of supersymmetry and degeneracy for an arbitrary number of Majorana fermions (even or odd) without to invoke any symmetry of Hamiltonian. Next, we analyze the supersymmetry at finite temperature using the thermofield dynamics formalism. Furthermore we derive thermal braiding operators through the Bogoliubov transformations and we find its action on a thermal Bell state.

cond-mat.stat-mech↗

A general formulation based on algebraic spinors for the quantum computation

In this work we explore the structure of Clifford algebras and the representations of the algebraic spinors in quantum information theory. Initially we present an general formulation through elements of left minimal ideals in tensor products of the Clifford algebra $Cl^{+}_{1,3}$. Posteriorly we perform some applications in quantum computation: qubits, entangled states, quantum gates, representations of the braid group, quantum teleportation, Majorana operators and supersymmetry. Finally, we discuss advantages related to standard Hilbert space formulation.

math-ph↗

Portfolio Theory, Information Theory and Tsallis Statistics

We developed a strategic of optimal portfolio based on information theory and Tsallis statistics. The growth rate of a stock market is defined by using $q$-deformed functions and we find that the wealth after n days with the optimal portfolio is given by a $q$-exponential function. In this context, the asymptotic optimality is investigated on causal portfolios, showing advantages of the optimal portfolio over an arbitrary choice of causal portfolios. Finally, we apply the formulation in a small number of stocks in brazilian stock market $[B]^{3}$ and analyzed the results.

q-fin.ST↗

An Approach by Representation of Algebras for Decoherence-Free Subspaces

The aim of this paper is to present a general algebraic formulation for the Decoherence-Free Subspaces (DFSs). For this purpose, we initially generalize some results of Pauli and Artin about semisimple algebras. Then we derive orthogonality theorems for algebras analogous to finite groups. In order to build the DFSs we consider the tensor product of Clifford algebras and left minimal ideals. Furthermore, we show that standard applications of group theory in quantum chemistry can be obtained in our formalism. Advantages and some perspectives are also discussed.

math-ph↗

Factor groups, semidirect product and quantum chemistry

In this paper we prove some general theorems about representations of finite groups arising from the inner semidirect product of groups. We show how these results can be used for standard applications of group theory in quantum chemistry through the orthogonality relations for the characters of irreducible representations. In this context, conditions for transitions between energy levels, projection operators and basis functions were determined. This approach applies to composite systems and it is illustrated by the dihedral group related to glycolate oxidase enzyme.

physics.gen-ph↗

Quasitriangular Hopf algebras, braid groups and quantum entanglement

The aim of the paper is to provide an method to obtain representations of the braid group through a set of quasitriangular Hopf algebras. In particular, these algebras may be derived from group algebras of cyclic groups with additional algebraic structures. In this context, by using the flip operator, it is possible to construct R-matrices that can be regarded as quantum logic gates capable of preserving quantum entanglement.

math-ph↗

Quantum Information, Thermofield Dynamics and Thermalized Bosonic Oscillator

We show through Thermofield Dynamics approach that the action of the thermalized quantum logic gate on the thermalized state is equivalent to thermalization of the state that arise from the application of the non-thermalized quantum logic gate. In particular, we study the effect of temperature on a mixed state associated to a system capable of implementing a CNOT quantum logic gate. According to a proposal in the literature, a way of implementing such a logic gate is by using a representation of the qubit states as elements of the Fock space of a bosonic system. We consider such a proposal and use the Thermofield Dynamics to determine the thermalized qubit states. The temperature acts as a quantum noise on pure states, making them a statistical mixture. In this context we analyze the fidelity as a function of the temperature and using the Mandel parameter, we determine temperature ranges for which the statistics of the system becomes subpoissonian, poissonian and superpoissonian. Finally, we calculate the Wigner function, allowing an analysis of the thermal state in phase space, and we obtain that the increase of temperature decreases non-classical properties of the system. The temperature range where one has a subpoissonian statistics and high fidelity is determined.

quant-ph↗