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We study vacuum and thermal expectation values of quantum scalar and Dirac fermion fields on anti-de Sitter space-time. Anti-de Sitter space-time is maximally symmetric and this enables expressions for the scalar and fermion vacuum Feynman Green's functions to be derived in closed form. We employ Hadamard renormalization to find the vacuum expectation values. The thermal Feynman Green's functions are constructed from the vacuum Feynman Green's functions using the imaginary time periodicity/anti-periodicity property for scalars/fermions. Focussing on massless fields with either conformal or minimal coupling to the space-time curvature (these two cases being the same for fermions) we compute the differences between the thermal and vacuum expectation values. We compare the resulting energy densities, pressures and pressure deviators with the corresponding classical quantities calculated using relativistic kinetic theory., 30 pages, 10 figures, minor changes, to appear in the Proceedings of the Fourth Amazonian Symposium on Physics, Belem, Brazil, 18-22 September 2017

We consider a real massive free quantum scalar field with arbitrary curvature coupling on $n$-dimensional anti-de Sitter space-time. We use Hadamard renormalization to find the vacuum expectation values of the quadratic field fluctuations and the stress-energy tensor, presenting explicit results for $n=2$ to $n=11$ inclusive., Version accepted for publication in Physical Review D, 26 pages, 5 figures

We outline an analytic method for computing the renormalised vacuum expectation value of the quadratic fluctuations and stress-energy tensor associated with a quantised scalar field propagating on $AdS_{n}$. Explicit results have been obtained using Hadamard renormalisation in the case of a massive neutral scalar field with arbitrary coupling to the curvature, for $n=2$ to $n=11$ inclusive., Comment: 3 pages, proceedings of the 13th Marcel Grossmann Meeting, Stockholm, Sweden, July 1-7, 2012

We consider the definition of the global vacuum state of a quantum scalar field on $n$-dimensional anti-de Sitter space-time as seen by an observer rotating about the polar axis. Since positive (or negative) frequency scalar field modes must have positive (or negative) Klein-Gordon norm respectively, we find that the only sensible choice of positive frequency corresponds to positive frequency as seen by a static observer. This means that the global rotating vacuum is identical to the global nonrotating vacuum. For $n\ge 4$, if the angular velocity of the rotating observer is smaller than the inverse of the anti-de Sitter radius of curvature, then modes with positive Klein-Gordon norm also have positive frequency as seen by the rotating observer.We comment on the implications of this result for the construction of global rotating thermal states., Comment: Minor changes (inc. title change), version accepted for publication in Physics Letters B, 4 pages

Alcohol and drug using clients of the Addiction Research Foundation were asked about their interest in receiving treatment for cigarette smoking. Forty-six percent said that they were “moderately” to “very much” interested in attending a treatment program if it were available. Despite a consistent preference for receiving smoking treatment after their alcohol or drug problem was treated, there was moderate interest in receiving smoking treatment during the alcohol or drug treatment among those who were very interested in receiving smoking treatment in general. Seventy-one percent reported that it would be “as difficult” or “more difficult” to give up cigarettes than the drug or alcohol which brought them to the hospital for treatment. The importance of treating smoking in alcohol and drug using clients is discussed.

About 1000 persons seeking treatment for alcohol or drug dependence were asked, relative to cigarettes, about the difficulty of quitting the use of the substance for which they were seeking treatment, the strength of their strongest urges to use, and the pleasure they derived from use. Fifty-seven percent said that cigarettes would be harder to quit using than their problem substance. These ratings were related to the level of cigarette dependence and the perceived difficulty of quitting the use of the problem substance. The alcohol-dependent persons were about four times more likely than the drug-dependent persons to say that their strongest urges for cigarettes were at least as great as their strongest urges for their problem substance. Cigarettes were generally rated as less pleasurable than alcohol or other drugs. Thus, experiential experts on dependence judge cigarette dependence as at least as "addictive" as other drug use, but not as pleasurable, indicating important similarities and differences between cigarette dependence and other forms of dependence on psychoactive substances. ( JAMA 1989;261:898-901)