N. David Mermin

Is the Moon There When Nobody Looks? Reality and the Quantum Theory

In May 1935, Albert Einstein, Boris Podolsky and Nathan Rosen published an argument that quantum mechanics fails to provide a complete description of physical reality. Today, 50 years later, the EPR paper and the theoretical and experimental work it inspired remain remarkable for the vivid illustration they provide of one of the most bizarre aspects of the world revealed to us by the quantum theory.

Quantum mysteries revisited

A gedanken gadget is described, based on an idea of Greenberger, Horne, and Zeilinger, that provides a more powerful demonstration of quantum nonlocality than Bell’s analysis of the Einstein–Podolsky–Rosen experiment.

Quantum Computer Science: An Introduction

Preface 1. Cbits and Qbits 2. General features and some simple examples 3. Breaking RSA encryption with a quantum computer 4. Searching with a quantum computer 5. Quantum error correction 6. Protocols that use just a few Qbits Appendices Index.

What is quantum mechanics trying to tell us

I explore whether it is possible to make sense of the quantum mechanical description of physical reality by taking the proper subject of physics to be correlation and only correlation, and by separating the problem of understanding the nature of quantum mechanics from the hard problem of understanding the nature of objective probability in individual systems, and the even harder problem of understanding the nature of conscious awareness. The resulting perspective on quantum mechanics is supported by some elementary but insufficiently emphasized theorems. Whether or not it is adequate as a new Weltanschauung, this point of view toward quantum mechanics provides a different perspective from which to teach the subject or explain its peculiar character to people in other fields.

Determination of Thermodynamic Green's Functions

In the study of thermodynamic correlation functions or Greens functions, one is naturally led to a calculation of values of the Fourier transform of the Greens function on a discrete set of points in the complex energy plane. It is shown that even though these points do not in general possess a limit point within the region of analyticity, one may still uniquely determine the Fourier transform of the Greens function directly from its values at these points.

An Introduction to QBism with an Application to the Locality of Quantum Mechanics

We give an introduction to the QBist interpretation of quantum mechanics, which removes the paradoxes, conundra, and pseudo-problems that have plagued quantum foundations for the past nine decades. As an example, we show in detail how this interpretation eliminates “quantum nonlocality.”

Quantum mysteries refined

A gedanken experiment discovered by Lucien Hardy is translated into a very direct black‐box gedanken demonstration of quantum nonlocality with red and green lights, using only two far apart detectors each of which operates in only two modes. The quantum mechanical underpinnings of the gedanken demonstration are quite simple. (This paper provides a text for the Klopsteg Memorial Lecture to the American Association of Physics Teachers at Notre Dame University, August 11, 1994.)

Relativity without light

The relativistic addition law for parallel velocities is derived directly from the principle of relativity and a few simple assumptions of smoothness and symmetry, without making use of the principle of the constancy of the velocity of light.

The Ithaca interpretation of quantum mechanics

I list several strong requirements for what I would consider a sensible interpretation of quantum mechanics and discuss two simple recent theorems which have important implications for such an interpretation. My talk will not clear everything up; indeed, you may conclude that it has not cleared anything up. But I hope it will provide a different perspective from which to view some old and vexing puzzles (or, if you believe nothing needs to be cleared up, some ancient verities.)

From Cbits to Qbits: Teaching computer scientists quantum mechanics

A strategy is suggested for teaching mathematically literate students, with no background in physics, just enough quantum mechanics for them to understand and develop algorithms in quantum computation and quantum information theory. Although the article as a whole addresses teachers of physics well versed in quantum mechanics, the central pedagogical development is addressed directly to computer scientists and mathematicians, with only occasional asides to their teacher. Physicists uninterested in quantum pedagogy may be amused (or irritated) by some of the views of standard quantum mechanics that arise naturally from this unorthodox perspective.