He Wen

NEW NOISE-BASED LOGIC REPRESENTATIONS TO AVOID SOME PROBLEMS WITH TIME COMPLEXITY

Instantaneous noise-based logic can avoid time-averaging, which implies significant potential for low-power parallel operations in beyond-Moore-law-chips. However, the universe (uniform superposition) will be zero with high probability (non-zero with exponentially low probability) in the random-telegraph-wave representation thus the operations with the universe would require exponential time-complexity. To fix this deficiency, we modify the amplitudes of the signals of the L and H states and achieve an exponential speedup compared to the old situation. Another improvement concerns the identification of a single product (hyperspace) state. We introduce a time shifted noise-based logic, which is constructed by shifting each reference signal with a small time delay. This modification implies an exponential speedup of single hyperspace vector identification compared to the former case and it requires the same, O(N) complexity as in quantum computing.

NOISE-BASED LOGIC: WHY NOISE? A COMPARATIVE STUDY OF THE NECESSITY OF RANDOMNESS OUT OF ORTHOGONALITY

Although noise-based logic shows potential advantages of reduced power dissipation and the ability of large parallel operations with low hardware and time complexity the question still persist: Is randomness really needed out of orthogonality? In this Letter, after some general thermodynamical considerations, we show relevant examples where we compare the computational complexity of logic systems based on orthogonal noise and sinusoidal signals, respectively. The conclusion is that in certain special-purpose applications noise-based logic is exponentially better than its sinusoidal version: Its computational complexity can be exponentially smaller to perform the same task.

Demons: Maxwell's demon, Szilard's engine and Landauer's erasure-dissipation

We briefly address Landauers Principle and some related issues in thermal demons. We show that an error-free Turing computer works in the zero-entropy limit, which proves Landauers derivation incorrect. To have a physical logic gate, memory or information-engine, a few essential components necessary for the operation of these devices are often neglected, such as various aspects of control, damping and the fluctuation-dissipation theorem. We also point out that bit erasure is typically not needed or used for the functioning of computers or engines (except for secure erasure).This talk addressed the following questions in the public debate at HoTPI: (i) energy dissipation limits of switches, memories and control; (ii) whether reversible computers are possible, or does their concept violate thermodynamics; (iii) Szilards engine, Maxwells demon and Landauers principle: corrections to their exposition in the literature; (iv) whether Landauers erasure–dissipation principle is valid, if the same energy dissipation holds for writing information, or if it is invalid; and (v) whether (non-secure) erasure of memories, or the writing of the same amount of information, dissipates most heat.

COMPLEX NOISE-BITS AND LARGE-SCALE INSTANTANEOUS PARALLEL OPERATIONS WITH LOW COMPLEXITY

We introduce the complex noise-bit as information carrier, which requires noise signals in two parallel wires instead of the single-wire representations of noise-based logic discussed so far. The immediate advantage of this new scheme is that, when we use random telegraph waves as noise carrier, the superposition of the first 2N integer numbers (obtained by the Achilles heel operation) yields nonzero values. We introduce basic instantaneous operations, with O(20) time and hardware complexity, including bit-value measurements in product states, single-bit and two-bit noise-gates (universality exists) that can instantaneously operate over large superpositions with full parallelism. We envision the possibility of implementing instantaneously running quantum algorithms on classical computers while using similar number of classical bits as the number of quantum bits emulated without the necessity of error corrections. Mathematical analysis and proofs are given.

Information theoretic security by the laws of classical physics

It has been shown recently that the use of two pairs of resistors with enhanced Johnson-noise and a Kirchhoff-loop-i.e., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol-for secure key distribution leads to information theoretic security levels superior to those of a quantum key distribution, including a natural immunity against a man-in-the-middle attack. This issue is becoming particularly timely because of the recent full cracks of practical quantum communicators, as shown in numerous peer-reviewed publications. This presentation first briefly surveys the KLJN system and then discusses related, essential questions such as: what are perfect and imperfect security characteristics of key distribution, and how can these two types of securities be unconditional (or information theoretical)? Finally the presentation contains a live demonstration.

Bird's-eye view on noise-based logic

Noise-based logic is a practically deterministic logic scheme inspired by the randomness of neural spikes and uses a system of uncorrelated stochastic processes and their superposition to represent the logic state. We briefly discuss various questions such as (i) What does practical determinism mean? (ii) Is noise-based logic a Turing machine? (iii) Is there hope to beat (the dreams of) quantum computation by a classical physical noise-based processor, and what are the minimum hardware requirements for that? Finally, (iv) we address the problem of random number generators and show that the common belief that quantum number generators are superior to classical (thermal) noise-based generators is nothing but a myth.

Facts, myths and fights about the KLJN classical physical key exchanger

This paper deals with the Kirchhoff-law-Johnson-noise (KLJN) classical statistical physical key exchange method and surveys criticism - often stemming from a lack of understanding of its underlying premises or from other errors - and our related responses against these, often unphysical, claims. Some of the attacks are valid, however, an extended KLJN system remains protected against all of them, implying that its unconditional security is not impacted.

Noise based logic: why noise?

Noise-based logic, similarly to the brain, is using different random noises to represent the different logic states. While the operation of brain logic is still an unsolved problem, noise-based logic shows potential advantages of reduced power dissipation and the ability of large parallel operations with low hardware and time complexity. But there is a fundamental question: is randomness really needed out of orthogonality? Orthogonal signal systems (similarly to orthogonal noises) can also represent multidimensional logic spaces and superpositions. So, does randomness add any advantage to orthogonality or is it disadvantageous due to the required statistical evaluation of signals? In this talk, after some general physical considerations, we show and analyze some specific examples to compare the computational complexities of logic systems based on orthogonal noise and sinusoidal signal systems, respectively. The conclusion is that, in certain special-purpose applications that are particularly relevant for mimicking quantum informatics, noise-based logic is exponentially better than its sinusoidal version: its computational complexity (time and hardware) can exponentially be smaller to perform the same task.