English page

Publication on statistical physics

October 25, 2007 (published online)

"Equation of state in a small system: Violation of an assumption of Maxwell’s demon"

T. Hondou

Department of Physics, Tohoku University - Sendai 980-8578, Japan and
Institut Curie, Section Recherche, UMR168 - 26 rue d’Ulm, 75248 Paris Cedex 05, France
EPL, 80 (2007) 50001

On-line publication page at EPL (Europhysics Letters)

doi: 10.1209/0295-5075/80/50001
Full text is avalable here (PDF version)

Others, see several databases.

Publication on electromagnetism

New paper!

Tsuyoshi Hondou, Takenori Ueda, Yasuhiro Sakata, Nobuto Tanigawa, Tetsu Suzuki, Taizo Kobayashi and Kensuke Ikeda:

"Passive Exposure to Mobile Phones: Enhancement of Intensity by Reflection"

J. Phys. Soc. Jpn. 75 084801(5 pages), (PDF version)


In a recent Letter [J. Phys. Soc. Jpn. 71(2002) 432], we reported a preliminary calculation and concluded that public exposure to mobile phones can be enhanced by microwave reflection in public spaces. In this paper, we confirm the significance of microwave reflection reported in our previous Letter by experimental and numerical studies. Furthermore, we show that ‘‘hot spots’’ often emerge in reflective areas, where the local exposure level is much higher than average. Such places include elevators, and we discuss other possible environments including trains, buses, cars, and airplanes. Our results indicate the risk of ‘‘passive exposure’’ to microwaves.

Numerical results in an elevator
Note that thedoor of the elevator is fully open:
(Movies are optimized in QuickTime)

  1. In case without reflection
    snapshot (PDF version), QuickTime Movie, MPEG-4, AVI
  2. In real case with reflection
    snapshot(PDF version), QuickTime Movie, MPEG-4, AVI
  3. 3D Movie in case with reflection
    QuickTime Movie, MPEG-4, AVI,
    where you can find hot spots more clearly.

You may remember typical specialists' comments in BBC News (Prof. Les Barclay) and inNew Scientist (Dr. Chou at Motorola), which were concerning our original report in 2002 (full version is available here). These comments were based on misunderstanding of fundamentals of electromagnetics. It is apparent that specialists are not familiarwith the basics of partial differential equations, although the fundamental equations of electromagnetics are in partial differential equations, namely, Maxwell's equations. In several public exposure assessments, specialists have naively assumed a boundary condition under which there is no reflection (even after 2002), although such an assumption is NEVER valid in several circumstances as just shown here (for details, see our paper).

Our original papers in 2002:

T. Hondou: “Rising level of public exposure to mobile phones: accumulation through additivity and reflectivity” J. Phys. Soc. Jpn. 71 p. 432 (2002),(PDF version).

T. Hondou: “Physical validity of assumptions for public exposure to mobile phones” J. Phys. Soc. Jpn. 71 p.3101 (2002) (PDF version).


Publication on scientific literacy

Abstract of an oral presentation at International Conference on Physics Education (ICPE) is here(PDF).

Contact detail

Tsuyoshi HONDOU, Ph.D
Department of Physics
Tohoku University
Sendai 980-8578 Japan
e-mail: hondou[at mark]mail.sci.tohoku.ac.jp