Ernesto Estrada (born 2 May 1966) is a

Cuba Cuba, officially the Republic of Cuba, is an island country, comprising the island of Cuba (largest island), Isla de la Juventud, and List of islands of Cuba, 4,195 islands, islets and cays surrounding the main island. It is located where the ...

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many countries in the Americas **Spanish cuisine **Spanish history **Spanish culture ...

scientist A scientist is a person who Scientific method, researches to advance knowledge in an Branches of science, area of the natural sciences. In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engag ...

. He has been Senior ARAID Researcher at the Institute of Mathematics and Applications at the

University of Zaragoza The University of Zaragoza, sometimes referred to as Saragossa University () is a public university with teaching campuses and research centres spread over the three provinces of Aragon (Spain). Founded in 1542, it is one of the List of oldest u ...

, Spain since 2019. Before that he was the chair in

Complexity Science A complex system is a system composed of many components that may interact with one another. Examples of complex systems are Earth's global climate, organisms, the human brain, infrastructure such as power grid, transportation or communication sy ...

, and full professor at the Department of

Mathematics Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...

and

Statistics Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...

of the

University of Strathclyde The University of Strathclyde () is a public research university located in Glasgow, Scotland. Founded in 1796 as the Andersonian Institute, it is Glasgow's second-oldest university, having received its royal charter in 1964 as the first techn ...

Glasgow Glasgow is the Cities of Scotland, most populous city in Scotland, located on the banks of the River Clyde in Strathclyde, west central Scotland. It is the List of cities in the United Kingdom, third-most-populous city in the United Kingdom ...

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

. He is known by his contributions in different disciplines, including

mathematical chemistry Mathematical chemistry is the area of research engaged in novel applications of mathematics to chemistry; it concerns itself principally with the mathematical modeling of chemical phenomena. Mathematical chemistry has also sometimes been called ...

and complex network theory.

Birth and education

Estrada was born in the city of Sancti Spiritus, in the central region of

. Since the age of 11 he studied in a school which specialized in

exact sciences The exact sciences or quantitative sciences, sometimes called the exact mathematical sciences, are those sciences "which admit of absolute precision in their results"; especially the mathematical sciences. Examples of the exact sciences are ma ...

. He later studied for a technical degree in

Analytical chemistry Analytical skill, Analytical chemistry studies and uses instruments and methods to Separation process, separate, identify, and Quantification (science), quantify matter. In practice, separation, identification or quantification may constitute t ...

in the technological institute IPQI Mártires de Girón

Havana Havana (; ) is the capital and largest city of Cuba. The heart of La Habana Province, Havana is the country's main port and commercial center.polyatomic anions in matrices of NaCl using

Infrared spectroscopy Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functio ...

. Between 1985 and 1990, he studied chemical sciences at the Central University of Las Villas in

Santa Clara, Cuba Santa Clara is the capital city of the Cuban province of Villa Clara. It is centrally located in the province and Cuba. Santa Clara is the fifth-most populous Cuban city, with a population of nearly 245,959. History Santa Clara was founde ...

, where he obtained his degree in only 4 of the 5 years established for the program. In the first years after graduation, Estrada investigated on the

organic synthesis Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the gen ...

and the use of

spectroscopy Spectroscopy is the field of study that measures and interprets electromagnetic spectra. In narrower contexts, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Spectro ...

for the characterization of new chemical entities with

pharmacological activity In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or ...

. This research introduced him to the world of

Computational chemistry Computational chemistry is a branch of chemistry that uses computer simulations to assist in solving chemical problems. It uses methods of theoretical chemistry incorporated into computer programs to calculate the structures and properties of mol ...

due to the requirement of using efficient methods for

drug design Drug design, often referred to as rational drug design or simply rational design, is the invention, inventive process of finding new medications based on the knowledge of a biological target. The drug is most commonly an organic compound, organi ...

and

drug discovery In the fields of medicine, biotechnology, and pharmacology, drug discovery is the process by which new candidate medications are discovered. Historically, drugs were discovered by identifying the active ingredient from traditional remedies or ...

. He is one of the co-authors of the patent for the

bactericide A bactericide or bacteriocide, sometimes abbreviated Bcidal, is a substance which kills bacteria. Bactericides are disinfectants, antiseptics, or antibiotics. However, material surfaces can also have bactericidal properties based solely on their p ...

and

fungicide Fungicides are pesticides used to kill parasitic fungi or their spores. Fungi can cause serious damage in agriculture, resulting in losses of yield and quality. Fungicides are used both in agriculture and to fight fungal infections in animals, ...

drug Furvina. In 1997, he obtained his PhD in

Mathematical chemistry Mathematical chemistry is the area of research engaged in novel applications of mathematics to chemistry; it concerns itself principally with the mathematical modeling of chemical phenomena. Mathematical chemistry has also sometimes been called ...

under the direction of Luis A. Montero Cabrera on the topic of "Graph Theory Applied to Molecular Design".

Academic career

After completing his PhD, Estrada spent some time as

Research fellow A research fellow is an academic research position at a university or a similar research institution, usually for academic staff or faculty members. A research fellow may act either as an independent investigator or under the supervision of a p ...

at the

University of Valencia The University of Valencia ( ), shortened to UV, is a public research university in Valencia, Spain. It is one of the oldest universities in Spain, and the oldest in the Valencian Community. It is regarded as one of Spain's leading academic i ...

, Spain with Prof. Jorge Galvez working on

and at the

Hebrew University of Jerusalem The Hebrew University of Jerusalem (HUJI; ) is an Israeli public university, public research university based in Jerusalem. Co-founded by Albert Einstein and Chaim Weizmann in July 1918, the public university officially opened on 1 April 1925. ...

with Prof.

David Avnir Prof. (emeritus) David Avnir (; born 12 June 1947; St. Ottilien Archabbey, St. Ottilien, Germany) is an Israeli Professor of chemistry at the Institute of Chemistry, The Hebrew University of Jerusalem. His scientific activities include sol-gel ...

working on molecular

symmetry number The symmetry number or symmetry order of an object is the number of different but indistinguishable (or equivalent) arrangements (or views) of the object, that is, it is the order of its symmetry group. The object can be a molecule, crystal lattice ...

s and

rotational partition function In chemistry, the rotational partition function relates the rotational degrees of freedom to the rotational part of the energy. Definition The total canonical partition function Z of a system of N identical, indistinguishable, noninteracting a ...

s. In 2000, he emigrated to

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

. Between 2002 and 2003, Estrada worked as a scientist at the Safety and Environmental Assurance Centre,

Unilever Unilever PLC () is a British multinational consumer packaged goods company headquartered in London, England. It was founded on 2 September 1929 following the merger of Dutch margarine producer Margarine Unie with British soap maker Lever B ...

in Colworth, U.K. He then obtained a position as "

Ramón y Cajal Ramón or Ramon may refer to: People Given name *Ramón (footballer, born 1950), Brazilian footballer * Ramón (footballer, born 1983), Brazilian footballer * Ramón (footballer, born 1988), Brazilian footballer *Ramón (footballer, born 1990), Br ...

" researcher at the

University of Santiago de Compostela The University of Santiago de Compostela - USC (, ) is a public university located in the city of Santiago de Compostela, Galicia, Spain. A second campus is located in Lugo, Galicia. It is one of the world's oldest universities in continuous o ...

, Spain. Between 2008 and 2018, Estrada occupied the chair in Complexity Science at the

. In 2019 he became ARAID Researcher at the

. In 2021 he incorporated to the IFISC research staff.

Research and achievements

Estrada has been a major contributor in the study of complex networks, where he has developed several approaches to investigate the

network topology Network topology is the arrangement of the elements (Data link, links, Node (networking), nodes, etc.) of a communication network. Network topology can be used to define or describe the arrangement of various types of telecommunication networks, ...

and

network dynamics Network dynamics is a research field for the study of networks whose status changes in time. The dynamics may refer to the structure of connections of the units of a network, to the collective internal state of the network, or both. The networked ...

. An index introduced by him in 1999 to characterize the degree of

protein folding Protein folding is the physical process by which a protein, after Protein biosynthesis, synthesis by a ribosome as a linear chain of Amino acid, amino acids, changes from an unstable random coil into a more ordered protein tertiary structure, t ...

, and then generalized to the study of complex networks in 2005, is nowadays widely known as the Estrada index of a graph or network. Estrada is also known in the field of

spectral graph theory In mathematics, spectral graph theory is the study of the properties of a Graph (discrete mathematics), graph in relationship to the characteristic polynomial, eigenvalues, and eigenvectors of matrices associated with the graph, such as its adjacen ...

where he has introduced several approaches to characterize the organizational architecture of Complex networks, such as the "subgraph

centrality In graph theory and network analysis, indicators of centrality assign numbers or rankings to nodes within a graph corresponding to their network position. Applications include identifying the most influential person(s) in a social network, ke ...

", "communicability", "spectral scaling", among others. His generalization of the

discrete Laplace operator In mathematics, the discrete Laplace operator is an analog of the continuous Laplace operator, defined so that it has meaning on a Graph (discrete mathematics), graph or a lattice (group), discrete grid. For the case of a finite-dimensional graph ...

, as the d-path Laplacians and their transforms, has opened several new avenues for studying long-range interactions in

. Estrada is also known in the area of

, in particular for the development and use of

molecular descriptor Molecular descriptors play a fundamental role in chemistry, pharmaceutical sciences, environmental protection policy, and health researches, as well as in quality control, being the way molecules, thought of as real bodies, are transformed into num ...

s based on the use of

Graph Theory In mathematics and computer science, graph theory is the study of ''graph (discrete mathematics), graphs'', which are mathematical structures used to model pairwise relations between objects. A graph in this context is made up of ''Vertex (graph ...

. In recent years he has developed mathematical approaches for the

Hückel method The Hückel method or Hückel molecular orbital theory, proposed by Erich Hückel in 1930, is a simple LCAO MO Method, method for calculating molecular orbitals as linear combinations of atomic orbitals. The theory predicts the molecular orbitals f ...

tight binding In solid-state physics, the tight-binding model (or TB model) is an approach to the calculation of electronic band structure using an approximate set of wave functions based upon superposition of wave functions for isolated atoms located at eac ...

model, such as for "graph energy", "

density matrix In quantum mechanics, a density matrix (or density operator) is a matrix used in calculating the probabilities of the outcomes of measurements performed on physical systems. It is a generalization of the state vectors or wavefunctions: while th ...

", "quantum molecular interference" in

molecular electronics Molecular electronics is the study and application of molecular building blocks for the fabrication of electronic components. It is an interdisciplinary area that spans physics, chemistry, and materials science. It provides a potential means to ...

, among others. The last work is in collaboration with

Roald Hoffmann Roald Hoffmann (born Roald Safran; July 18, 1937) is a Polish-American theoretical chemist who won the 1981 Nobel Prize in Chemistry. He has also published plays and poetry. He is the Frank H. T. Rhodes Professor of Humane Letters Emeritus at C ...

Awards and Distinctions

*2005, Elected Member of the

International Academy of Mathematical Chemistry The International Academy of Mathematical Chemistry (IAMC) was founded in Dubrovnik, Croatia, in 2005 by Milan Randić. It is an organization for chemistry and mathematics avocation; its predecessors have been around since the 1930s. There are 88 ...

. *2007, Recipient of the Prize as Outstanding Scientist,

in recognition for "''his valuable contributions in developing and applying graph theory to solve problems in many interdisciplinary areas, such as chemistry, physics, biology, ecology and technology"''. *2014, Recipient of the

Royal Society Wolfson Research Merit Award The Royal Society Wolfson Fellowship, known as the Royal Society Wolfson Research Merit Award until 2020, is a 5 years fellowship awarded by the Royal Society since 2000. The scheme is described by the Royal Society as providing ''long-term flexib ...

of the Royal Society of London, which recognises "''scientists of outstanding achievement and potential''". *2014, Elected as Member of the

Academia Europaea The Academia Europaea is a pan-European Academy of humanities, letters, law, and sciences. The Academia was founded in 1988 as a functioning Europe-wide Academy that encompasses all fields of scholarly inquiry. It acts as co-ordinator of Europe ...

. *2019, Elected as Member of the Latin American Academy of Science. *2019, Elected

SIAM Fellow The SIAM Fellowship is an award and fellowship that recognizes outstanding members of the Society for Industrial and Applied Mathematics (SIAM). The goal of the program is to: *honor SIAM members who are recognized by their peers as distinguishe ...

"''for outstanding contributions to mathematical chemistry and network science''".

Editorial Activities

*Editor-in-Chief, Journal of Complex Networks, Oxford University Press. *Editorial Board, MATCH. Communications in Mathematical and in Computer Chemistry. *Editorial Board,

SIAM Journal on Applied Mathematics The ''SIAM Journal on Applied Mathematics'' is a peer-reviewed academic journal in applied mathematics published by the Society for Industrial and Applied Mathematics (SIAM), with Paul A. Martin (Colorado School of Mines) as its editor-in-chief. I ...

. *Editorial Board, Proceedings of the Royal Society, A. *Editorial Board, Mathematics.

Books

*2011. The Structure of Complex Networks. Theory and Applications. Oxford University Press. *2015. A First Course in Network Theory. Oxford University Press, with P. Knight.

References

External links

*
Profile at University of StrathclydeJournal of Complex NetworksWolfson Research Merit Award of the Royal Society of London
{{DEFAULTSORT:Estrada, Ernesto Living people 1966 births 21st-century Cuban scientists Complex systems scientists Academics of the University of Strathclyde Mathematical chemistry People from Sancti Spíritus Royal Society Wolfson Research Merit Award holders Fellows of the Society for Industrial and Applied Mathematics Network scientists