91 citations · 594 across the 36 of their papers we have counts for
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A New Quantum Random Number Generator Certified by Value Indefiniteness
José Manuel Agüero Trejo, Cristian S. Calude
In this paper we propose a new ternary QRNG based on measuring located value indefinite observables with probabilities and prove that every sequence generated is max…
Experimentally Probing the Algorithmic Randomness and Incomputability of Quantum Randomness
Alastair A. Abbott, Cristian S. Calude, Michael J. Dinneen +1
The advantages of quantum random number generators (QRNGs) over pseudo-random number generators (PRNGs) are normally attributed to the nature of quantum measurements. This is often…
Quassical Computing
Edward H. "Ned" Allen, Cristian S. Calude
We present a class of hybrid classical systems using quantum co-processors and point out that unlike purely quantum computers, such hybrids can be both universal and Turing complet…
The Road to Quantum Computational Supremacy
Cristian S. Calude, Elena Calude
We present an idiosyncratic view of the race for quantum computational supremacy. Google's approach and IBM challenge are examined. An unexpected side-effect of the race is the sig…
A variant of the Kochen-Specker theorem localising value indefiniteness
Alastair A. Abbott, Cristian S. Calude, Karl Svozil
The Kochen-Specker theorem proves the inability to assign, simultaneously, noncontextual definite values to all (of a finite set of) quantum mechanical observables in a consistent…
A Non-Probabilistic Model of Relativised Predictability in Physics
Alastair A. Abbott, Cristian S. Calude, Karl Svozil
Little effort has been devoted to studying generalised notions or models of (un)predictability, yet is an important concept throughout physics and plays a central role in quantum i…
On the unpredictability of individual quantum measurement outcomes
Alastair A. Abbott, Cristian S. Calude, Karl Svozil
We develop a general, non-probabilistic model of prediction which is suitable for assessing the (un)predictability of individual physical events. We use this model to provide, for…
Embedding Quantum Universes into Classical Ones
Cristian S. Calude, Peter H. Hertling, Karl Svozil
Do the partial order and ortholattice operations of a quantum logic correspond to the logical implication and connectives of classical logic? Re-phrased, how far might a classical…
Kochen-Specker Theorem: Two Geometric Proofs
Cristian S. Calude, Peter H. Hertling, Karl Svozil
We present two geometric proofs of the Kochen-Specker theorem. A quite similar argument has been used by Cooke, Keane, and Moran, as well as by Kalmbach in her book to derive the G…
Value-indefinite observables are almost everywhere
Alastair A. Abbott, Cristian S. Calude, Karl Svozil
Kochen-Specker theorems assure the breakdown of certain types of non-contextual hidden variable theories through the non-existence of global, holistic frame functions; alas they do…
Spectral Representation of Some Computably Enumerable Sets With an Application to Quantum Provability
Cristian S. Calude, Kohtaro Tadaki
We propose a new type of quantum computer which is used to prove a spectral representation for a class F of computable sets. When S in F codes the theorems of a formal system, the…
Strong Kochen-Specker theorem and incomputability of quantum randomness
Alastair A. Abbott, Cristian S. Calude, Jonathan Conder +1
The Kochen-Specker theorem shows the impossibility for a hidden variable theory to consistently assign values to certain (finite) sets of observables in a way that is non-contextua…
A Quantum Random Number Generator Certified by Value Indefiniteness
Alastair A. Abbott, Cristian S. Calude, Karl Svozil
In this paper we propose a quantum random number generator (QRNG) which utilizes an entangled photon pair in a Bell singlet state, and is certified explicitly by value indefinitene…
Understanding the Quantum Computational Speed-up via De-quantisation
Alastair A. Abbott, Cristian S. Calude
While it seems possible that quantum computers may allow for algorithms offering a computational speed-up over classical algorithms for some problems, the issue is poorly understoo…
Experimental Evidence of Quantum Randomness Incomputability
Cristian S. Calude, Michael J. Dinneen, Monica Dumitrescu +1
In contrast with software-generated randomness (called pseudo-randomness), quantum randomness is provable incomputable, i.e.\ it is not exactly reproducible by any algorithm. We pr…
How Random Is Quantum Randomness? An Experimental Approach
Cristian S. Calude, Michael J. Dinneen, Monica Dumitrescu +1
Our aim is to experimentally study the possibility of distinguishing between quantum sources of randomness--recently proved to be theoretically incomputable--and some well-known co…
Quantum randomness and value indefiniteness
Cristian S. Calude, Karl Svozil
As computability implies value definiteness, certain sequences of quantum outcomes cannot be computable.
De-Quantising the Solution of Deutsch's Problem
Cristian S. Calude
Probably the simplest and most frequently used way to illustrate the power of quantum computing is to solve the so-called {\it Deutsch's problem}. Consider a Boolean function $f: \…
From Heisenberg to Goedel via Chaitin
C. S. Calude, M. A. Stay
In 1927 Heisenberg discovered that the ``more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa''. Four years later Göd…
Transcending the Limits of Turing Computability
Vadim A. Adamyan, Cristian S. Calude, Boris S. Pavlov
Hypercomputation or super-Turing computation is a ``computation'' that transcends the limit imposed by Turing's model of computability. The field still faces some basic questions,…
Incompleteness, Complexity, Randomness and Beyond
Cristian S. Calude
Goedel's Incompleteness Theorems have the same scientific status as Einstein's principle of relativity, Heisenberg's uncertainty principle, and Watson and Crick's double helix mode…
Coins, Quantum Measurements, and Turing's Barrier
Cristian S. Calude, Boris Pavlov
Is there any hope for quantum computing to challenge the Turing barrier, i.e. to solve an undecidable problem, to compute an uncomputable function? According to Feynman's '82 argum…