Radio waves -- Tissue Refractive Index

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Discussion Overview

The discussion centers on the refractive index of tissue for radio waves in the frequency range of 1 Hz to 1 MHz. Participants explore the relationship between tissue properties, relative permittivity, and the implications for electromagnetic wave propagation, particularly in the context of potential applications involving electro-sensitive macromolecules.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Some participants note that the refractive index (RI) of tissue is approximately 1.4 for light but decreases at lower frequencies, with one suggesting that the RI may be higher at radio frequencies.
  • To compute the RI, some participants propose estimating or measuring the relative permittivity (Er) of the tissue, with values for Er varying widely among different types of flesh.
  • One participant calculates the RI based on Er, suggesting a range of RI between 3 and 10, while another mentions obtaining a specific RI value of 3.2.
  • There is a discussion about the visibility of tissue effects at low radio frequencies, with some arguing that radio waves are too long to interact significantly with small biological structures.
  • Some participants express interest in using radio waves to influence electro-sensitive macromolecules, discussing the need for specific frequencies and the challenges of identifying them without disturbing the system.
  • Concerns are raised about the potential for electromagnetic radiation to cause unwanted heating in tissue, alongside the intended effects.
  • One participant suggests using a capacitor setup instead of radio waves for their experiments, while another questions the feasibility of using the same equipment for different frequency ranges.
  • There are references to agricultural practices and the potential use of electromagnetic radiation to influence seed germination, highlighting a broader application of the discussed concepts.

Areas of Agreement / Disagreement

Participants express differing views on the refractive index of tissue at radio frequencies, the implications of using radio waves for biological applications, and the effectiveness of various experimental approaches. The discussion remains unresolved with multiple competing perspectives presented.

Contextual Notes

Participants mention the variability in tissue properties and the dependence on specific conditions, such as the type of tissue and the frequency used. There are also unresolved questions regarding the reliability of sources for relative permittivity and the specific frequencies required for certain biological effects.

  • #31
I think it's got to be even harder than that.

First, DNA curls. So any "magic frequency" changes cell-by-cell depending on exactly how it's curled. Putting that aside, bacterial DNA looks like human DNA: the chemistry is the same. Only the content is different. You can't attack an A group to T group: you need a frequency that attacks the whole thing coherently. Figuring that out will be Real Doggone Hard, and building a transmitter that precise will be Real Doggone Hard.
 
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  • #32
@roxyboy
Target the molecular chemistry of the transcription process. That is the only time you will see the internal sequence of the DNA or RNA going past during replication. You need gene scissors, not a microwave oven.
 
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  • #33
Thread paused for a bit for Moderation...
 
  • #34
renormalize said:
The references cited are wholley inadequate to support your claims.
Agreed.

@roxyboy -- this thread will remain closed. If you have a valid reference that you want to ask questions about, start a new thread and post links for the reference and ask *specific* questions about that reference. Please avoid making assertions at PF that are not backed up by the mainstream scientific literature.
 
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