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# Physics/eletromagnetic wave and antenna

Question
QUESTION: Dear Sir.
When I read article on internet, I am very confused what is true and fictional.
Pls. Teach me with scientific knowlege.
1. Because of nano tech and material development,
Scientist could make the electromagnetic wave antenna very small such like 1cm hair size or below
2. And also could make antenna self charged style, so without the help of rechargimg from the battery, if antenna or chip is inserted in body or inhaled in lung, it could send the signal pr receive the wave and signals.
3. That means shadow goverment makes chip and antenna and insert it without notice... and attack individual by sending electromagnetic wave to indiviuals who have the chip or antenna.
I almost know it would be fictional tale.. but really want to know whether it is fiction or true with the help of scientific knowledge.

ANSWER: The antennae that transmit and receive electromagnetic waves are roughly the same scale as the wavelength transmitted.  It's fine if it's just kind of in the range, but you can't go completely way below the range of the signal wave and still receive efficiently.  That's why different wavelengths of light behave so differently.  You can't just transmit and receive electromagnetic waves without using any power at all, that violates conservation of energy.  You can make tiny antennae with or without nanotech, they just won't work.  And antennae also can't just "self charge" from nothing...but that's beside the point.  To receive you don't need a charge, but you'd still need ridiculous amounts of power to actually harm a human being from a distance.  The power received without being right in the beam of a directional antenna (and a good one, well-aimed) would be minimal.  So your fictional story does violate the laws of physics, you can't just randomly transmit a signal to attack a person.

---------- FOLLOW-UP ----------

QUESTION: Dear sir.
Thank you very much.
Whether there is very little antenna powered by body or not,
Impotant thing is if there is no direct wave shooting weapon, it is impossible to harm people,
And until now there is no such kinds of weapon which trace the target from long distance and shoot the electromagnetic wave to target directly (when we see the movie, big antenna trace and shoot the electromagnetic wave to the target or satellite tace and shoot the wave...it is only fictional tale..right?)
Thank you

ANSWER: You can "trace" a target with a normal broadcast if it's implanted with something that responds to that normal broadcast.  However, that broadcast is too weak to harm.  After that, you would have to place a directional weapon in direct line of fire to cause harm.

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May I ask last query.

Flankly to say, because I am not the expert of material physcis or science, I cannot image that is there any material which be powered only by human electricity when material is implanted or inhaled.
But as far as I know, chip which satellite could trace needs gps receiver and antenna basically, but that gps system and antenna cannot be made by such kinds of materials.. right?
So until know in my point of view, hair sized and weight chip cannot be developed... right?
(it is only fictional concept) right?

There are current technological limits to what can power a GPS locator that can actually transmit a signal.  They can be made quite small, however, and broadcast a location via cell phone towers with quite small power requirements.  It's possible to envision exotic power supplies that could provide a tracking beacon in something that's only millimeters in size.  That kind of stealth technology is more in the area of expertise of a computer hacker or spy, however, I'm not even sure who I'd ask about it.

Physics

Volunteer

#### Dr. Stephen O. Nelson

##### Expertise

I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

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I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Education/Credentials
Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.