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Centimeter Wavelengths

|< < Prev #3224 (March 25, 2026)

Title text: Yes, the cosmic microwave background is great, but what about the earthly microwave foreground?

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Explanation

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Cosmic microwave background radiation is microwave radiation which permeates throughout the entire observable universe. It originated from light released during proton-electron recombination shortly after the Big Bang, which has since grown less energetic due to cosmological redshift, becoming background microwave radiation which we see today. This radiation is not visible to the naked eye, but can be detected using specific radio instruments, including centimeter wavelength antennas, which are antennas designed to detect signals in the 1~10 cm wavelength range (from 30GHz down to 3GHz); the core range of the wider microwave band of radio waves.

In 1978, American astronomers and physicists Arno Allan Penzias and Robert Woodrow Wilson were awarded the Nobel Prize in Physics "for their discovery of cosmic microwave background radiation". During routine experiments with the 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, including the 'removal' of nesting pigeons and their droppings, they found that this background noise was still present. This led to their accidental discovery of the cosmic microwave background radiation, and thus provided a key confirmation of the Big Bang hypothesis itself. (In the world of xkcd, this could explain this phenomenon.)

Wi-Fi networks also transmit their signals using electromagnetic waves at similar wavelengths. 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. Many other sources (notably microwave ovens) can also produce emissions in the same wavelengths, which can interfere with those signals, they can interfere with each other, and intervening structures, etc., can obstruct signals (or create spurious ones), all of which can cause annoying loss of function necessitating investigation and intervention to stabilise the signals. Less technically capable workers may need extra support to properly setup up their networks, while too capable ones could also risk breaking things in more profound ways...

Randall is bemoaning the fact that none of the efforts of people working in the IT sector, who may be spending even more time troubleshooting issues related to Wi-Fi connectivity on their site, have been recognised in the way that Penzias and Wilson have been.

This comic is something of an inverse of the sentiment expressed in 3154: Physics Insight.

The title text may be a reference to Perytons, a signal first seen by astronomers in the early 2000s. Perytons looked similar to fast radio bursts, which are very energetic astronomical signals, the origin of which is still not understood. Perytons, on the other hand, were found to be the result of opening the door of a microwave oven in the radio observatory, which let out a short burst of microwave radiation as the magnetron in the oven turned off.

Transcript

[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.

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Discussion

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This is a test. PoolloverNathan^{[stalk the blue seas]} 20:48, 16 March 2021 (UTC)

This is not. —While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 19:23) 18:38, 17 November 2022 (UTC)

A foreign student asked me to help fight against his math teacher. That was unusual. He was in that class for just a couple of weeks. The teacher's phone number was sent to me. The student asked me to spam-call the teacher. 172.71.155.55 22:58, 18 September 2023 (UTC)

here i'm just messing around in html, ignore this

^furhhfghure _{guyrburgryhuyvfr} "rvhru"

interesting way of writing quotations xd

hmmm this one of putting "<p>" in a line break will come in handy for when i want it to start at the same place than the first line

Please beware that <p> on mediawiki also disables automatic paragraph breaks, so you need a closing </p> or you'll break automatic paragraph formatting for the rest of the page. Zmatt (talk) 22:06, 31 July 2024 (UTC)

edit: da hek did that "</div>" come from An user who has no account yet (talk) 14:14, 13 October 2023 (UTC)

hi uh its hard to get here. is this a reference to undocumented feature??? hmm... this is interesting.
108.162.241.216 02:05, 23 November 2023 (UTC)

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yum yum [citation needed]

Hiuiedeixgeyceiyedhcdiedcve {{trout}}

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<a href=" [AT THE JULY 28TH MEETING][tab] "Cancel the meeting! Our cover is blown."> More testing: hello ​ does​this​work (yes​it​does) This isn't a good name (talk) 22:44, 28 January 2026 (UTC)

‮hi 164.58.172.158 14:21, 23 February 2026 (UTC)

What is this?????????????????????? King Pando (talk) 04:25, 10 March 2026 (UTC)‭
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Recent comments:

26 March 2026

		N    17:09	Talk:3224: Centimeter Wavelengths‎‎ (7 changes | history) . . (+1,709)‎ . . [King Pando‎; Broseph‎; TheusafBOT‎; 98.19.37.29‎; 82.132.237.127‎; 82.13.184.33‎; 216.25.182.141‎]
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		m	07:42 (cur | prev) . . (+109)‎ . . Broseph (talk | contribs)
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		m	03:45 (cur | prev) . . (+174)‎ . . King Pando (talk | contribs)
		N	03:30 (cur | prev) . . (+113)‎ . . TheusafBOT (talk | contribs) (Created by theusafBOT: talk page for 3224)

		12:27	Talk:2244: Thumbtacks And String‎‎ (2 changes | history) . . (+337)‎ . . [82.132.237.127‎; 147.161.250.108‎]
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25 March 2026

		21:57	Talk:3223: Inflation Timeline‎‎ (4 changes | history) . . (+1,559)‎ . . [WikipedianPolitician‎; Lettherebedarklight‎; 81.179.199.253‎ (2×)]
			21:57 (cur | prev) . . (+734)‎ . . 81.179.199.253 (talk)
			06:53 (cur | prev) . . (+30)‎ . . Lettherebedarklight (talk | contribs) (fix unsigned)
		m	00:17 (cur | prev) . . (+678)‎ . . WikipedianPolitician (talk | contribs) (comment, interesting context)
			00:11 (cur | prev) . . (+117)‎ . . 81.179.199.253 (talk)

		18:50	Talk:1203: Time Machines‎‎ (2 changes | history) . . (+1,350)‎ . . [82.132.238.50‎; 2600:1700:3cf4:1180:6c57:a298:a080:a187‎]
			18:50 (cur | prev) . . (+876)‎ . . 82.132.238.50 (talk)
			03:35 (cur | prev) . . (+474)‎ . . 2600:1700:3cf4:1180:6c57:a298:a080:a187 (talk)

05:01

Talk:483: Fiction Rule of Thumb‎ (diff | hist) . . (-3)‎ . . 2001:4c4e:1c0b:2500:530a:c00a:69f7:ca1e (talk)

		00:21	Talk:287: NP-Complete‎‎ (2 changes | history) . . (+257)‎ . . [WikipedianPolitician‎; 81.179.199.253‎]
		m	00:21 (cur | prev) . . (+131)‎ . . WikipedianPolitician (talk | contribs)
			00:16 (cur | prev) . . (+126)‎ . . 81.179.199.253 (talk)

24 March 2026

		23:46	Talk:287: NP-Complete‎‎ (3 changes | history) . . (+279)‎ . . [WikipedianPolitician‎ (3×)]
		m	23:46 (cur | prev) . . (+2)‎ . . WikipedianPolitician (talk | contribs) (→‎Should this be in the Multiple Cueballs category?: sorry I forgot about edit summaries/this has just been me fixing the heading format)
		m	23:45 (cur | prev) . . (+2)‎ . . WikipedianPolitician (talk | contribs) (→‎Should this be in the Multiple Cueballs category?)
			23:45 (cur | prev) . . (+275)‎ . . WikipedianPolitician (talk | contribs) (→‎Should this be in the Multiple Cueballs category?: new section)

		22:03	Talk:3223: Inflation Timeline‎‎ (12 changes | history) . . (+2,296)‎ . . [User 8496351‎; Jp5424‎; 42.book.addict‎; 82.132.237.186‎; 82.13.184.33‎; 80.187.75.215‎; 2a12:f43:143e:0:c172:a03d:12fe:51aa‎; 2a00:23cc:d248:8901:d030:98e4:e22b:d2ef‎; 204.77.3.72‎; 2001:1c02:1a9d:9700:2416:3c14:b648:3fd0‎; Lettherebedarklight‎ (2×)]
			22:03 (cur | prev) . . (+201)‎ . . 80.187.75.215 (talk)
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			18:18 (cur | prev) . . (+200)‎ . . Jp5424 (talk | contribs) (Weird X axis)
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			07:56 (cur | prev) . . (+560)‎ . . User 8496351 (talk | contribs)
			05:34 (cur | prev) . . (+41)‎ . . Lettherebedarklight (talk | contribs) (unsigned)
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20:25

Talk:3201: Proof Without Content‎ (diff | hist) . . (+146)‎ . . 184.94.17.26 (talk)

20:04

Talk:3221: Landscape Features‎ (diff | hist) . . (+337)‎ . . 2600:1006:b137:6466:48c3:2bc9:bcbb:7cd4 (talk) (Maybe "landscape" as a political term?)

15:50

Talk:2192: Review‎ (diff | hist) . . (+560)‎ . . 204.77.3.72 (talk)

23 March 2026

21:03

Talk:3220: Rotational Gravity‎ (diff | hist) . . (+498)‎ . . 136.47.216.1 (talk)

		N    19:47	Talk:3223: Inflation Timeline‎‎ (5 changes | history) . . (+680)‎ . . [TheusafBOT‎; 2a02:26f7:e344:4000:c000::f‎; 155.33.87.241‎; Dextrous Fred‎ (2×)]
			19:47 (cur | prev) . . (+99)‎ . . Dextrous Fred (talk | contribs) (Minor comment)
			19:47 (cur | prev) . . (+292)‎ . . Dextrous Fred (talk | contribs) (Minor comment)
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			19:10 (cur | prev) . . (+49)‎ . . 2a02:26f7:e344:4000:c000::f (talk) (→‎Sexy?: new section)
		N	18:30 (cur | prev) . . (+113)‎ . . TheusafBOT (talk | contribs) (Created by theusafBOT: talk page for 3223)

		11:51	Talk:3222: Star Formation‎‎ (3 changes | history) . . (-1)‎ . . [82.132.239.91‎; 82.13.184.33‎ (2×)]
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			11:27 (cur | prev) . . (-7)‎ . . 82.132.239.91 (talk) (Undo revision 408695 by 82.13.184.33 (talk) No need for additional indent, looks like secondary reply to original question, as much as direct follow-up to the first reply to it.)
			09:31 (cur | prev) . . (+7)‎ . . 82.13.184.33 (talk)

		11:22	Talk:3221: Landscape Features‎‎ (4 changes | history) . . (+429)‎ . . [John‎; 82.13.184.33‎ (3×)]
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