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meyol99
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What is the longest wave-lenght of a photon particle in the nature and can it be longer?
What is the longest wave-lenght of a photon?
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In summary, there is no simple answer for the longest wavelength of a photon particle in nature. The length of the universe is often considered a practical limit, but there is no fundamental maximum for wavelength. However, at very low frequencies, it becomes more difficult to detect and generate photons due to the low energy and signal-to-noise ratio. Additionally, the ability to detect and generate depends on the size and structure of the radiating source. EM theory does not impose an upper limit for wavelength, but it would take an infinite time to generate a wave of infinite wavelength.
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There is no simply defined upper limit for the wavelength of light. I suppose one mught argue the length of the universe is a practical limit.
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Almeisan
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Why would the length of the universe be a limit? I am sure there are radio waves in my room right with wave lengths much bigger than my room. Am I missing something?
Also, in the cases of black holes and places in the universe too far away for us to view, aren't these red shifted into infinitely long wavelengths?
Also, in the cases of black holes and places in the universe too far away for us to view, aren't these red shifted into infinitely long wavelengths?
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mathman
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In theory there is no longest wavelength. As a practical matter, the length of the universe may be the longest in existence.
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sophiecentaur
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Your question is fundamentally flawed, I'm afraid because it's harder than that, in fact. Photons do not 'have a wavelength'. They are not classical particles but quantum entities. What you 'are allowed' to say is that the EM wave they are associated with, has a wavelength. There is no fundamental maximum for wavelength but EM at very low frequencies has very low energy photons and becomes harder and harder to detect because you just can't make receiving equipment that can 'extract' the signal out of the space it's traveling through. (The antenna would have to be several thousand km long to intercept a 50Hz signal)Mevludin Licina said:
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mathman
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In addition they would be very hard to generate.sophiecentaur said:
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derek10
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why can battery-operated amplifiers and oscilloscopes pick up the mains noise (50 Hz in Europe) when you touch the input cable?sophiecentaur said:
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sophiecentaur
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Not at all hard to generate - all you need to do is to move electrons around with a low frequency electric field. The problem is to generate and radiate enough power at that frequency to be detected remotely in the presence of the ubiquitous noise. All problems in life come down to Signal To Noise Ratio.mathman said:
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sophiecentaur
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Because the em wave is not a 'launched wave, traveling free through space but guided on the wire. To launch a significant level of signal into space. from a circuit, it has to be 'matched', which requires a radiating structure that's not much smaller than one wavelength. A wire / person link is a totally different situation.derek10 said:
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my2cts
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EM theory imposes no upper limit.
It will take an infinite time to generate a wave of infinite wavelength.
What on Earth (or in the universe) do you have in mind with this question?
It will take an infinite time to generate a wave of infinite wavelength.
What on Earth (or in the universe) do you have in mind with this question?
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meyol99
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The other variant of my question would be what is the smallest frequency of an EM wave
a) in general ?
b) detetected ?
a) in general ?
b) detetected ?
- #12
my2cts
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Same answers. The smallest frequency is zero (as far as EM theory is concerned) and it would take an infinite time to detect it.
FAQ: What is the longest wave-lenght of a photon?
1. What is the longest wavelength of a photon?
The longest wavelength of a photon is an infinite wavelength, also known as a zero-frequency photon. This type of photon has no energy and is considered a virtual particle that exists for a very short period of time.
2. Can a photon have an infinite wavelength?
Yes, a photon can have an infinite wavelength, also known as a zero-frequency photon. These photons have no energy and are considered virtual particles that exist for a very short period of time.
3. What is the relationship between wavelength and energy in a photon?
The wavelength of a photon is inversely proportional to its energy. This means that as the wavelength increases, the energy of the photon decreases. The formula for this relationship is: E = h*c/λ, where E is energy, h is Planck's constant, c is the speed of light, and λ is the wavelength.
4. What is the longest wavelength of electromagnetic radiation?
The longest wavelength of electromagnetic radiation is approximately 10^26 meters, which corresponds to a frequency of 3x10^-27 Hz. This type of radiation is known as cosmic microwave background radiation and is a remnant of the Big Bang.
5. Can a photon have a wavelength longer than the observable universe?
No, a photon cannot have a wavelength longer than the observable universe, which is estimated to be about 93 billion light-years in diameter. This is because the observable universe is considered the maximum limit for the propagation of light and therefore, the longest possible wavelength for a photon.