3224: Centimeter Wavelengths

2026-03-26T07:54:42Z

ISbit: added link to other xkcd post about cryptic wifi networks

{{comic
| number = 3224
| date = March 25, 2026
| title = Centimeter Wavelengths
| image = centimeter_wavelengths_2x.png
| imagesize = 381x335px
| noexpand = true
| titletext = Yes, the cosmic microwave background is great, but what about the earthly microwave foreground?
}}

==Explanation==
{{incomplete|This page was created recently. Don't remove this notice too soon.}}

{{w|Cosmic microwave background radiation}} is {{w|Microwave|microwave radiation}} which permeates throughout the entire observable universe. It originated from light released during proton-electron recombination shortly after the {{w|Big Bang}}, which has since grown less energetic due to {{w|cosmological redshift}}, becoming microwave radiation which we see today. This radiation is not visible to the naked eye, but can be detected using specific radio instruments, including {{w|Super high frequency|centimeter wavelength}} antennas, which are antennas designed to make detection in the 1-10 wavelength range; the Microwave band of radio waves.

In this comic, "Penzias & Wilson" refers to American astronomers and physicists {{w|Arno Allan Penzias}} and {{w|Robert Woodrow Wilson}} who, in 1978, were awarded the Nobel Prize in Physics "for their discovery of {{w|cosmic microwave background radiation}}". The story of their discovery was that during routine experiments with the {{w|Holmdel Horn Antenna}}, a centimeter wavelength antenna, Penzias and Wilson discovered that they were detecting a static background noise that they could not explain. After "debugging" the antenna and removing all potential sources of noise, they found that this background noise was still present, leading to their accidental discovery of the cosmic microwave background radiation. In the world of xkcd, this could explain this [https://www.explainxkcd.com/wiki/index.php/2199:_Cryptic_Wifi_Networks phenomenon]

On the other hand, Wi-Fi networks also transmit the signal using electromagnetic waves at around similar wavelengths. [https://study-ccnp.com/wifi-frequency-phase-wavelength The common frequency bands currently used] are 2.4 GHz and 5 GHz, and 6 GHz is seeing more use recently. The three ranges would roughly correspond to wavelengths of 12.5cm (4.92in), 6cm (2.36in), and 5cm (1.97in) respectively.

This comic is alluding to the fact that Penzias and Wilson are the only people who have won a Nobel prize from trying to debug a centimeter wavelength antenna, due to their accidental discovery of the cosmic microwave background radiation. On the other hand, people working in the IT sector may be spending even more time troubleshooting issues related to Wi-Fi connectivity on their site. Less technically capable workers may need extra support to properly setup up their workflow, while [[:Category:Cueball's computer problems|too capable ones]] could also risk breaking things in [[:2949: Network Configuration|more profound ways]]...

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}

:[A scatter plot graph with the Y axis of "time spent debugging centimeter-wavelength antennas" and X axis of "Nobel prizes awarded as a result". The X axis has the numbers 0 and 1 marked, while the Y axis has no numbers marked. Many dots arranged vertically appear at 0 on the X axis (zero Nobel prizes), collectively labeled as "I.T. people troubleshooting WiFi issues". A single dot appears at 1 on the X axis, vertically about 1/3 of the height of the graph up, labeled "Penzias & Wilson".]
:[Caption below the panel:]
:I just think the other people working in the field deserve at least a ''little'' recognition.

{{comic discussion}}<noinclude>

[[Category:Physics]]
[[Category:Scatter plots]]
[[Category:Comics featuring real people]]

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3224: Centimeter Wavelengths