Whole body radio frequency resonance a conceptual blunder yet a most striking coincidence, some brief comments by Dr Chris Barnes, Bangor Scientific and Educational Consultants
Dr Barnes Homepage http://www.drchrisbarnes.co.uk
A commonly measured body resonant frequency is in the range 50-70 MHz although there are others. Simple antenna theory and body height is often used to explain this effect. The use of such theory is shown here to be flawed and irrelevant and indeed when the body is considered properly as a dielectric resonator its VHF resonance is shown to be associated with the breadth of the torso rather than with body height. This has implications which give rise to a second body resonance in the HF frequency range and may help explain previously apparently contradictory cancer epidemiology studies. Some quantum mechanical considerations are briefly discussed and a new theory as to how FM modulated emissions may still produce quantum biological effects is advanced.
With growing concern about RF safety and the interaction of RF energy with biological tissues it is desirable to know something of the resonant frequency or frequencies of a human body.
Practical measurements often yield maximum absorption of RF, therefore assumed resonant frequency to be somewhere in the region of 50-70 MHz.
A number of text books make the assumption that this is because of the behaviour of body height as a quarter wave resonator but are they correct to do so?
The range of free space wavelengths encompassed by the above frequency range is 4.28-6m exactly. A quarter of this range is 1.07 -1.5m. It would seem if the body were metallic a young teenage child ought to resonate within this frequency range.
However the body is far from metallic, it is a complex dielectric material or inhomogeneous collection of dielectric materials of widely varying complex permittivity and conductivities.
Further it is well known that when a dipole antenna is placed under liquid its length is reduced by a factor approximately related to the square root of the dielectric constant of the liquid concerned. Meaning for instance a dipole under water will be about 1/9th the length it would be in air.
Based on this premise alone before we even consider the precise dielectric properties of a body, being predominantly water we might expect a vertical height resonance between 5-8 MHz. So where then does the measured figure come from? The answer is it would seem to come from the width or circumference of the body trunk or torso.
When precise figures are added for the average complex permittivity and conductivity of the body for an average adult male we arrive at a resonance figure of 8.87 MHz for the height and 68 MHz for the torso.
Relevance to Cancer epidemiology studies.
It is interesting to note that there have been studies linking an excess of various types of cancer to living in the proximity of various kinds of radio transmitter. There has been a study which showed an increase in .............. near the Short Wave Transmitters of Vatican city. Similarly there was study by Dolk ( ref ) which showed increased cancer incidence near the Sutton Coldfield fm transmitter. Here we have two frequencies almost a decade apart apparently inducing similar effects. However, when one considers the body as a 3D dielectric resonator it seems more plausible how this could happen. 8.87 MHz lies remarkably close to the 31m Broadcast Band which is the most heavily used of all the Short Wave Broadcast bands mainly because there is propagation at most times of day and night. Similarly, 68 MHz lies not far below the 87-108 MHz FM broadcast band.
Quantum mechanical considerations and energy at a cellular level.
It is perhaps easiest to see how the short wave broadcast could be a problem depending on the antenna design and A-field. Certainly short wave broadcasts use amplitude modulation which at very high power levels can even re-distribute metal ions in the body.
But how can FM be a problem? The hypothesis of the present author is both new and novel. FM broadcasting using Horizontal Polarisation which will have maximum impingement on the Torso. The Torso contains moving structures including the beating heart, the lungs, the diaphragm and the digestive system. Such movements impose modulations on the incoming wave amplitude. Others have already shown that a moving standing wave sequence at these frequencies can trigger a nervous system body response. Similar such modulations will perhaps trigger responses at the cellular level.
In each case one would expect responses not only in the near field vicinity of the antenna but also at considerable quantised distances(refs) in the far field.
It is hoped to report further on these aspects, particularly with respect to a new theory for some types of childhood cancer in the near future.