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As in the title, I'm wondering is it possible.

I think it is possible, because we have powerful enough radiotechniques and gamma radiation are just EM waves, not particles. However I think is useless, because it costs too much.

Can anyone say something more about this?

  • How much power would consume such emitter?
  • Would it be helpful anywhere?
  • How huge frequencies of current would it use in the antenna?
  • How big device would it be?
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  • $\begingroup$ If I say that gamma radiation are just particles, not EM waves, both of us would be wrong and correct at the same time!! $\endgroup$ – DarioP May 19 '14 at 20:13
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Is it possible to produce gamma radiaton using radio emitter?

Unlikely. A 'radio emitter' consists of, at least, some type of antenna and a transmitter to drive that antenna.

The size of the antenna is related to the wavelength of the transmitted radio wave, e.g., half-wave dipole, quarter-wave monopole.

But the wavelength of gamma rays is less than the diameter of an atom.

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    $\begingroup$ So, such antenna would be smaller than the atom, I conclude from this article? $\endgroup$ – user46147 May 19 '14 at 17:52
  • $\begingroup$ @user46147, radio antennas are made from atoms. Can something be smaller than that with which it is made? $\endgroup$ – Alfred Centauri May 19 '14 at 17:55
  • $\begingroup$ Of course such antena would be just a theoretical being. It would be technically impossible, and now I know why. Thanks :) $\endgroup$ – user46147 May 19 '14 at 17:57
  • $\begingroup$ @AlfredCentauri I don't really agree it is an antenna size issue. Technically you can build antennas at multiple wavelengths. In this case you'd want to scale the antenna up, rather than the common case of scaling the antenna down. $\endgroup$ – user6972 May 19 '14 at 17:59
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    $\begingroup$ @user6972, it's not just antenna size that is a problem but the size of the 'radio' transmitter which, frankly, should be obvious. From the Wiki article on Terahertz radiation: "Similarly, in this frequency range [within the Terahertz gap] the generation and modulation of coherent electromagnetic signals ceases to be possible by the conventional electronic devices used to generate radio waves and microwaves, and requires new devices and techniques." $\endgroup$ – Alfred Centauri May 19 '14 at 18:17
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Radios work with a form of radiation called non-ionizing radiation. This means the EM waves contain enough energy to move the atoms (charges) around but not enough energy to break particles loose. Ionizing radiation removes particles because they carry a lot more energy and can break atomic bonds. These travel as UV-rays, x-rays or gamma-rays.

spectrum

In essence, "this is not the radio you were looking for". An x-ray machine is a form of "radio", but it is not something safe to use because the high energy damages human tissues and DNA. Repeated exposure to listening to that x-ray station would cause mutations and cellular damage way beyond just hurting your ear drums.


EDIT:

Jokes aside, the "radio" would have to work on a very high frequency to achieve ionizing radiation, not high power levels. The above graph illustrates the equation that energy is proportional to frequency $E=h v$

Thermal energy (via RF/Microwaves) can be added to a substance via non-ionized radiation in large amounts and perhaps the target material will produce some ionizing radiation in a burst (like blackbody radiation), but it would not release much in comparison to how much thermal energy you would have to generate to do this. Ionizing radiation for medical devices use kinetic energy of accelerators to move particles up to ionizing levels and it is much more efficient.


It appears I'm not making myself clear, so I'll try one more time.

"Antennas" for this discussion is a structure designed to radiate EM waves at a specific frequency. And you can build antennas $>\lambda$ unlike Alfred's claims. Antennas work at multiples of $\lambda$ as well as fractions of $\lambda$. Engineers tend to avoid larger antennas ($>\lambda$) in radio frequency bands for radiation pattern simplicity and smaller sizes. Here's a link showing multiple $\lambda$ designs with different radiation patterns.

How I understand your question is "How can I make radio waves at 1GHz ($1*10^9$Hz) work as gamma-rays at $3*10^{19}$Hz?" (Note 1 THz is only $1*10^{12}$)

You can't produce ionized radiation directly from non-ionized energy levels. The transition between non-ionizing and ionizing levels make this impossible to do without introducing a 3rd process to boost the energy level of some target substance which you are going to ionize and/or accelerate. Size of the radiator (or antenna) is not really relevant. Energy is the issue and how matter responds to higher levels of energy excitation.

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  • $\begingroup$ You misunderstood me. I don't want to listen to the radio. I want to know is it possible to generate gamma radiation using almost the same technique as used to generate harmless radiowaves. I.e. : Is it just the matter of emitter power or something more. I don't want to listen to it. Just switch a switch ant generate gamma, with no need for isotope storage. $\endgroup$ – user46147 May 19 '14 at 17:26
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    $\begingroup$ @user46147 I was just having a little fun with your question. From the graph you can see that the energy and momentum of a photon depend only on its frequency $E=h v$ So it's not a matter of turning your FM transmitter up to 11. Perhaps you could pour enough RF thermal energy into something and get it to emit some ionizing radiation but it would be extremely inefficient. $\endgroup$ – user6972 May 19 '14 at 17:35
  • $\begingroup$ Are you sure that this is so easy? And how advanced would be such equipment? Why noone uses this? Is it waste of money? Why? $\endgroup$ – user46147 May 19 '14 at 17:38
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    $\begingroup$ @user46147 It is used. But the process usually involves adding energy kinetically to particles rather than thermally. Medical devices create ionizing radiation using accelerators for example. $\endgroup$ – user6972 May 19 '14 at 17:44
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    $\begingroup$ @user46147 No. It's completely impossible because energy at those high levels does not conduct along metallic paths (or circuits). They ionize the matter they interact with. It is not related to antenna sizes or power. Gamma-rays can only be controlled, amplified, and modulated with fields, not matter, unlike non-ionizing energy like radio waves. $\endgroup$ – user6972 May 21 '14 at 23:35
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The 0.51 MeV photon from positron-electron annihilation is considerd a gamma ray and industrial X-Ray tubes emit photons that are over 1 MeV. So there is some overlap in the terminology. If your radio produces electric fields of 500 KeV or more, there is SOME way to make gamma rays come from something loosely called an antenna.

For example, your antenna could be a cyclotron or a modified Klystron tube. You can transmit X-Rays with an old improperly used vacuum tube and an automobile spark coil.

In the typical analysis of RF antennas, the electrons in the metal shake back and forth and create EM waves in the far field. If you shake the electrons harder and they bump into things, you can get X-Ray/Gamma-Ray radiation. Is there an energy gap between radio and X-Ray? I have never seen an antenna that shoots yellow light. However, a number of novel techniques have emerged in the last 20 years and I wold doubt any proof. I recall a proof that the X-Ray LASER was impossible, then Dr. Teller showed an arrangement of tungsten rods pumped by a nuclear explosion. You never know.

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  • $\begingroup$ You're combining processes. For example an antenna that shoots yellow light is one that is producing so much thermal heat (due to power) that the atoms emit black body radiation in the visible band (glowing yellow) this is just a way to produce ionizing radiation using non-ionizing sources. $\endgroup$ – user6972 May 19 '14 at 20:05
  • $\begingroup$ Your answer counters Alfred Centauri's one. He claimed that I would need antenna smaller than an atom. His statement is supported by wikipedia. I wouldn't mind if you commented on antenna's size. $\endgroup$ – user46147 May 19 '14 at 20:08
  • $\begingroup$ @user6972 So I can call a lightbulb "antenna"? I never thought about it this way. It seems logical now. $\endgroup$ – user46147 May 19 '14 at 20:10
  • $\begingroup$ @user46147, one can generalize the concept of antenna to the point that it looses almost all meaning. Indeed, almost any real conductor is an (typically undesired) antenna which is why we have the study of electromagnetic compatibility. However, your question is much less interesting if antenna includes, for example, a decaying nucleus radiating a gamma ray photon. As I understand your question, your asking why we can't radiate EM waves of gamma ray wavelength using radio or radio like apparatus and that is the context of my answer. user6972 answers from a different perspective. $\endgroup$ – Alfred Centauri May 19 '14 at 20:42
  • $\begingroup$ Indeed, @AlfredCentauri you understood me correctly. Comment about lightbulb was just a divagation. Your answer considering antenna's size is in my opinion the best. $\endgroup$ – user46147 May 19 '14 at 21:13
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There are no known transistors or oscillators yet produced that can handle 10^19 frequancies, we are still experimenting at terahertz range 10^12 or thereabouts so the simple answer is no.

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It is extremely exciting when people describe the operation of a weapon without understanding it. Or its purpose. The problem is currently the lack of energy. The described are about what they can do. No, what will it feed? Actually, nobody gives such a devastating device to the public any detailed blueprints. The one who creates the first ... sets Einstein and Ede Teller behind the line.

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