What Lies Beyond the EM Spectrum?

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In summary: Say, I had a gamma ray with a frequency of 1056 Hz. If I were to boost myself up to the frequency, would I be emitting any particles along the way?Hah, you're right. :) For example, this could when the gamma ray scatters (inelastically) from a nucleus.I think I understand, Sylas. To further elaborate on... Say, I had a gamma ray with a frequency of 1056 Hz. If I were to boost myself up to the frequency, would I be emitting any particles along the way?Yes, you would be emitting particles. However, because the energy of these particles is so high, they would be destroyed very quickly.
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DanontheMoon
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Quick question from a complete science ignoramus.

The electromagnetic spectrum is described as a continuum, correct? So, given the scales of frequencies that our science is familiar with, The high end would be gamma rays, with frequencies of 300 EHz, the low end being extremely low frequency waves of 3 Hz.

Here's my question. What's past gamma rays or ELF waves? Could there be other dimensions in which their particular slice of the EM spectrum lies wholly outside of ours, that exist in the same space as our own?
 
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DanontheMoon said:
Quick question from a complete science ignoramus.

The electromagnetic spectrum is described as a continuum, correct? So, given the scales of frequencies that our science is familiar with, The high end would be gamma rays, with frequencies of 300 EHz, the low end being extremely low frequency waves of 3 Hz.

Here's my question. What's past gamma rays or ELF waves? Could there be other dimensions in which their particular slice of the EM spectrum lies wholly outside of ours, that exist in the same space as our own?

A continuum means, by definition, that there's no special boundary at which there's anything especially different. There may be a greatest energy gamma ray that exists, but it would still be just a gamma ray.

The highest frequency gamma rays detects have been about 1027 Hz, though there is reason to think there may be some a couple of orders of magntitude higher. This isa about 1000 YHz; Yotta (Y) is the highest metric prefix, at 1024. EHz would be 1018.

The lower end is harder to detect, because the energies are so low, but theoretically there would be some which are small fractions of a Hz.

Cheers -- sylas
 
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Okay, thanks the response! So, if you had a wavelength with a frequency of.. say, 1056 Hz, it'd still be just a Gamma ray?
 
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DanontheMoon said:
Okay, thanks the response! So, if you had a wavelength with a frequency of.. say, 1056 Hz, it'd still be just a Gamma ray?

We'd need a new word for something like that, I think. I don't think there's any process in the universe that could make such a beast. But if it did, it would still be a photon... with an energy of about 6.6*1022 J. Thats more energy than all the Earth's total estimated fossil fuel reserves put together, coal included.
 
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  • #5
sylas said:
We'd need a new word for something like that, I think. I don't think there's any process in the universe that could make such a beast. But if it did, it would still be a photon... with an energy of about 6.6*1022 J. Thats more energy than all the Earth's total estimated fossil fuel reserves put together, coal included.

Could one get such a photon by a change of reference frame?
 
  • #6
atyy said:
Could one get such a photon by a change of reference frame?

Yes. The most energetic gamma rays in our galaxy have a frequency of about 1027 Hz. So you need a gamma factor of about 1029 to get them up to the 1056 Hz.

Assuming you and your high speed spaceship weigh about 1000 kg, the total energy to boost you up to the required velocity would be about 9*1048 J. That's about 50 times larger than the total mass-energy of our solar system.

Not to mention the shielding you will need to carry to protect you from the cosmic background radiation, which is now shifted to hard gamma radiation many times more energetic than has ever been measured.
 
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For a photon with energy higher than 2me = 1.02 MeV, it is kinematically possible to be converted to an electron-positron pair. This process is even possible at tree level according to QED and one can calculate the relevant cross-section, which gives the lifetime in this case.
 
  • #8
Dickfore said:
For a photon with energy higher than 2me = 1.02 MeV, it is kinematically possible to be converted to an electron-positron pair. This process is even possible at tree level according to QED and one can calculate the relevant cross-section, which gives the lifetime in this case.

I think it is a requirement that the photon be interacting with other particles... otherwise you cannot conserve both energy and momentum.
 
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sylas said:
I think it is a requirement that the photon be interacting with other particles... otherwise you cannot conserve both energy and momentum.

Hah, you're right. :) For example, this could when the gamma ray scatters (inelastically) from a nucleus.

EDIT:

If a gamma - ray scatters from a nucleus with mass M, then the threshold energy (we assume units with c = 1) is:


[tex]
E_{\gamma \textrm{th}} = 2 m_{e} \left[ \frac{2 m_{e}}{M} + \sqrt{1 + \left( \frac{2 m_{e}}{M} \right)^{2}} \right]
[/tex]

Because the mass of any nucleus is much greater than 1 MeV, the expression in square brackets is approximately equal to 1, so the threshold energy is still correct.
 
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  • #10
I think I understand, Sylas. To further elaborate on my question though, could it be possible that there could be photons that have such a high OR low level of energy that we can't detect them, and corresponding forms of matter that likewise don't interact with us?

I'm an artist, not a scientist, so, if I can graphically represent what I'm talking about:

Let's say that this is our EM Spectrum, or the part of it that we deal with:

330px-EM_Spectrum_Properties_edit.svg.png


So, let's zoom waaaaay out from that little portion of the spectrum. Could it be possible that there are entire energetic 'realms' lying far outside the wavelengths that we commonly encounter?

[PLAIN]http://img191.imageshack.us/img191/1230/emwhatif.jpg
 
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DanontheMoon said:
I think I understand, Sylas. To further elaborate on my question though, could it be possible that there could be photons that have such a high OR low level of energy that we can't detect them, and corresponding forms of matter that likewise don't interact with us?

I'm an artist, not a scientist, so, if I can graphically represent what I'm talking about:

Let's say that this is our EM Spectrum, or the part of it that we deal with:

330px-EM_Spectrum_Properties_edit.svg.png


So, let's zoom waaaaay out from that little portion of the spectrum. Could it be possible that there are entire energetic 'realms' lying far outside the wavelengths that we commonly encounter?

[PLAIN]http://img191.imageshack.us/img191/1230/emwhatif.jpg[/QUOTE]

No, I don't think so. The idea that having too much energy means you can't detect it is IMO absurd on the face of it; and there is also the problem that there's no known process to generate the beast.

Cheers -- sylas
 
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FAQ: What Lies Beyond the EM Spectrum?

What is the EM spectrum?

The EM spectrum, also known as the electromagnetic spectrum, is the range of all possible frequencies of electromagnetic radiation. This includes all forms of light, radio waves, microwaves, and other forms of electromagnetic radiation.

What lies beyond the EM spectrum?

Beyond the EM spectrum are forms of radiation with higher frequencies, such as gamma rays and x-rays, as well as forms with lower frequencies, such as infrared and radio waves. These forms of radiation are not visible to the human eye but can still be detected and measured with specialized equipment.

Why is it important to study what lies beyond the EM spectrum?

Studying what lies beyond the EM spectrum allows scientists to gain a deeper understanding of the universe and its properties. It also helps in the development of new technologies, such as medical imaging devices and communication systems.

How do we detect and measure radiation beyond the EM spectrum?

Radiation beyond the EM spectrum can be detected and measured using specialized equipment such as gamma ray detectors, x-ray machines, and infrared cameras. These devices are designed to detect and measure specific frequencies of radiation.

What are some potential dangers of radiation beyond the EM spectrum?

Radiation beyond the EM spectrum can be harmful to living organisms, as it has the potential to damage cells and DNA. Exposure to high levels of radiation, such as gamma rays and x-rays, can lead to serious health issues and even death. It is important to use proper safety measures when working with or around these forms of radiation.

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