Assoc. Prof. Robert Kudelić, PhD of the University of Zagreb Faculty of Organization and Informatics (Republic of Croatia) recently delivered an invited lecture titled “Quantum Computation 101” at the University of Lisbon. The visit also supported collaboration with Assoc. Prof. Carlos Costa linked to the Croatian Science Foundation (HRZZ) project The Algorithmic Entrepreneurial Process Reshaping the Dominant Paradigm, underscoring how fundamental computer science and emerging hardware sit alongside questions of innovation and economic organization.
From tunneling to circuits
Professor Kudelić framed quantum computing as a way to see quantum mechanics through computer science. He opened with ideas such as the quantum tunneling effect—where, because of wave–particle duality, an electron can pass through an insulating barrier—and stressed why classical machines struggle to represent the state of many quantum particles.
The lecture traced a historical arc: from Planck (1900) and early debates on superposition and entanglement, through Feynman’s vision of simulating physics with computers (1981), Deutsch’s formalization of a quantum computer and the circuit–gate model, landmark algorithms (Bernstein–Vazirani, Shor, Grover), and milestones in experimental systems (IBM, Intel, Google’s Sycamore claim of quantum supremacy, and more recent demonstrations into the mid-2020s).
Insights the audience gained
Highlights included quantum parallelism (exponential state space with measurement forcing careful use of interference) and superpolynomial speedup in complexity terms (e.g. exponential versus polynomial scaling), contrasted with improvements that are large but not “superpolynomial” in that technical sense.
Practical discussion followed DiVincenzo’s criteria (scalable qubits, initialization, long coherence, universal gates, measurement, plus communication criteria), implementation routes (ions, superconductors, photons, etc.), and the scale of error correction in real devices. Applications touched simulation, search, cryptography and post-quantum preparation, optimization, and quantum communication concepts such as dense coding and the quantum internet.
Outlook
The conclusion stressed that every problem solvable on a quantum computer remains solvable classically—the open question is speed—while decoherence, scalability, and error correction remain the main engineering hurdles. Variational methods were noted as a near-term bridge.
The Lisbon event was a moment of international cooperation, with the HRZZ (UIP-2025-02-7375) project and the FCT (Fundação para a Ciência e a Tecnologia) project providing a thread between entrepreneurial and algorithmic research agendas and frontier topics in quantum computation.
*Any opinions, findings, and conclusions or recommendations expressed in project materials are those of the author(s) and do not necessarily reflect the views of the Croatian Science Foundation nor of the Fundação para a Ciência e a Tecnologia.
