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Page "Antimatter" ¶ 7
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frequency and wavelength
it was noted by Bohr that the existence of any sort of wave packet implies uncertainty in the wave frequency and wavelength, since a spread of frequencies is needed to create the packet itself.
The frequency chosen is in the visible spectrum near green, corresponding to a wavelength of about 555 nanometers.
The CMBR has a thermal black body spectrum at a temperature of 2. 725 K, which peaks at the microwave range frequency of 160. 2 GHz, corresponding to a 1. 873 mm wavelength.
If measured instead per unit wavelength, using Wien's law, the peak is at 1. 06 mm corresponding to a frequency of 283 GHz.
* The dependence of wave velocity on frequency or wavelength:
The electromagnetic spectrum, in order of increasing frequency and decreasing wavelength, consists of radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
where v is the speed of the wave ( c in a vacuum, or less in other media ), f is the frequency and λ is the wavelength.
Likewise, the momentum p of a photon is also proportional to its frequency and inversely proportional to its wavelength:
As a wave, it is characterized by a velocity ( the speed of light ), wavelength, and frequency.
However, certain ionospheric effects begin to block incoming radiowaves from space, when their frequency is less than about 10 MHz ( wavelength longer than about 30 meters ).
The energy E, frequency v, and wavelength λ of a photon are related by
Since frequency and wavelength are inversely proportional, this is equivalent to saying that the frequency of the light is reduced towards the red part of the light spectrum, giving this phenomenon the name redshift.
Group velocity ( equal to an electron's speed ) should not be confused with phase velocity ( equal to the product of the electron's frequency multiplied by its wavelength ).
When light strikes a material, most of the light is absorbed while a smaller amount of a particular frequency or wavelength is reflected.
Infrared spectroscopy ( IR spectroscopy ) is the spectroscopy that deals with the infrared region of the electromagnetic spectrum, that is light with a longer wavelength and lower frequency than visible light.
Primary properties of visible light are intensity, propagation direction, frequency or wavelength spectrum, and polarisation, while its speed in a vacuum, 299, 792, 458 meters per second ( about 300, 000 kilometers per second ), is one of the fundamental constants of nature.
When a beam of light crosses the boundary between a vacuum and another medium, or between two different media, the wavelength of the light changes, but the frequency remains constant.
* Second harmonic generation ( SHG ), or frequency doubling, generation of light with a doubled frequency ( half the wavelength ), two photons are destroyed creating a single photon at two times the frequency.
* Third harmonic generation ( THG ), generation of light with a tripled frequency ( one-third the wavelength ), three photons are destroyed creating a single photon at three times the frequency.
If two waves of the same wavelength and frequency are in phase, both the wave crests and wave troughs align.

frequency and gamma
Rodolfo Llinás, for example, proposed that consciousness results from recurrent thalamo-cortical resonance where the specific thalamocortical systems ( content ) and the non-specific ( centromedial thalamus ) thalamocortical systems ( context ) interact in the gamma band frequency via temporal coincidence.
By contrast, for higher frequency radiations at ultraviolet frequencies and above ( i. e., X-rays and gamma rays ) the damage to chemical materials and living cells by EMR is far larger than that done by simple heating, due to the ability of single photons in such high frequency EMR to damage individual molecules chemically.
In 1910 British physicist William Henry Bragg demonstrated that gamma rays are electromagnetic radiation, not particles, and in 1914 Rutherford and Edward Andrade measured their wavelengths, and found that they were similar to X-rays but with shorter wavelengths and higher frequency.
Electromagnetic radiation is classified into types according to the frequency of the wave, these types include ( in order of increasing frequency ): radio waves, microwaves, terahertz radiation, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
A secondary gamma ray with less energy ( hence lower frequency ) also emerges from the interaction.
Gamma decay releases gamma rays, which unlike alpha and beta radiation are not matter but electromagnetic radiation of very high frequency, and therefore energy.
) the frequency of the involved photons will vary widely, and lines can be observed across the electromagnetic spectrum, from radio waves to gamma rays.
All of these regions can produce a variety of observed energy, mostly in the form of a nonthermal spectrum ranging from very low frequency radio to extremely energetic gamma rays, with a high polarization ( typically a few percent ) at some frequencies.
The main frequency ranges include delta, theta, alpha, the sensorimotor rhythm, low beta, high beta, and gamma.
Examples of the dynamic fields of electromagnetic radiation ( in order of increasing frequency ): radio waves, microwaves, light ( infrared, visible light and ultraviolet ), x-rays and gamma rays.
When the perceived beat frequency corresponds to the delta, theta, alpha, beta, or gamma range of brainwave frequencies, the brainwaves entrain to or move towards the beat frequency.
Radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X rays and gamma rays are shown to be the same electromagnetic radiation phenomenon, differing one from the other only in frequency of vibration.
Because the energy of each photon of EM radiation is proportional to its frequency, gamma rays have sufficient energy that they are typically observed by counting individual photons.
SR has yet to be fully explained in biological systems, but neural synchrony in the brain ( specifically in the gamma wave frequency ) has been suggested as a possible neural mechanism for SR by researchers who have investigated the perception of " subconscious " visual sensation.
* RHESSI was the first satellite to accurately measure terrestrial gamma-ray flashes that come from thunder storms, and RHESSI found that such flashes occur more often than thought and the gamma rays have a higher frequency on average than the average for cosmic sources.
A gamma wave is a pattern of neural oscillation in humans with a frequency between 25 to 100 Hz, though 40 Hz is typical.
The gamma waves were most apparent at a frequency of 40 Hz ; this indicates that the gamma waves evoked by FS manipulation are a resonating brain circuit property.
This was observed at a frequency of 25 – 40 Hz, the rhythm of gamma waves.

frequency and rays
We know that the number of radio and television impulses, sound waves, ultra-violet rays, etc., that may occupy the very same space, each solitary upon its own frequency, is infinite.
The history of quantum chemistry essentially began with the 1838 discovery of cathode rays by Michael Faraday, the 1859 statement of the black body radiation problem by Gustav Kirchhoff, the 1877 suggestion by Ludwig Boltzmann that the energy states of a physical system could be discrete, and the 1900 quantum hypothesis by Max Planck that any energy radiating atomic system can theoretically be divided into a number of discrete energy elements ε such that each of these energy elements is proportional to the frequency ν with which they each individually radiate energy and a numerical value called Planck ’ s Constant.
By making one arm of the experiment much shorter than the other, a change in velocity of the earth would cause changes in the travel times of the light rays, from which a fringe shift would result unless the frequency of the light source changed to the same degree.
Gamma rays are the highest-energy form of electromagnetic radiation, being physically exactly like all other forms ( e. g., X rays, visible light, infrared, radio ) except for higher photon energy and frequency, and shorter wavelength.
Most Shan have a phobia of sunlight because the electromagnetic frequency of the Sun's rays poisons their metabolism.
If the glow discharge seen in the gas of Crookes tubes was produced by the moving cathode rays, the light radiated from them in the direction they were moving, down the tube, would be shifted in frequency due to the Doppler effect.

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