2358: Gravitational Wave Pulsars

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Gravitational Wave Pulsars
The most important attributes of a vector in 3-space are {Location, Location, Location}
Title text: The most important attributes of a vector in 3-space are {Location, Location, Location}


Pulsars are rotating neutron stars, which have a very precise period of rotation. Pulsars are highly magnetized, causing them to emit a beam of electromagnetic radiation that rotates across their sky. Radio astronomers can detect these beams if and when they point towards Earth, where they appear as pulses of radiation with highly stable periods. They use the pulsars' periodic beams to try to detect gravitational waves by tracking the rotation period of an ensemble of pulsars extremely precisely over long periods of time. Disturbances in the pulsars' rotation period will be measurable at Earth. A disturbance from a passing gravitational wave will have a particular signature across the ensemble of pulsars, and will be thus detected. The process is called "pulsar timing", or just "timing" for short.

Ponytail presents this to Cueball as a joke - specifically, a joke about comedy. One of the most important aspects of comedy is revealing the punchline with correct timing. Ponytail sets Cueball up for a joke like, "Ask me what the secret of comedy is." / "What's the secret of--" / "Timing!" In this format, the punchline ("Timing!") deliberately comes too soon, which makes it funny because the timing is bad. Ponytail also replaces the secret to comedy with the secret to detecting gravitational waves with pulsars, to set up the joke about the word "timing".

The title text is a play on a well-known real estate saying that the three most important parts of a real estate deal are "location, location, location." In 3D Euclidean space, the three Cartesian coordinates {X, Y, Z} all refer to locations along the three axes.


[Single panel with Ponytail and Cueball standing facing each other]
Ponytail: Ask me what the secret to detecting gravitational waves using pulsars is.
Cueball: What's the secret to detecting grav—
Ponytail: Timing!

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This actually an old joke "what is the secret of comedy" Steve (talk) 07:58, 13 September 2020 (UTC)

This one isn't very funny.. 19:37, 11 September 2020 (UTC)

It's not topical either. I sense filler. 19:49, 11 September 2020 (UTC)
Perhaps not as topical as US Presidential Elections or COVID-19, but there have been at least two research papers on gravity wave phenomena in the past two weeks, I’ve been seeing YouTube vids about it pop up in my feed and various people tweeting about it. See the research paper, "GW190521: A Binary Black Hole Coalescence with a Total Mass of 150 Solar Masses," which was published in Physical Review Letters on September 2, 2020 and The research paper, "Properties and Astrophysical Implications of the 150 Solar Mass Binary Black Hole Merger GW190521," published in Astrophysical Journal Letters on September 2, 2020. 05:13, 12 September 2020 (UTC)
Unless there's a hidden joke that I don't get 20:05, 11 September 2020 (UTC)
There's a common joke that roughly goes "What is the secret to a good joke timing?" (said all at once) 21:18, 11 September 2020 (UTC)

Context is here: https://arxiv.org/abs/2009.04496

Related to this? [GW190521 Wiki] OhFFS (talk) 21:13, 11 September 2020 (UTC)
No, the gravitational waves have different periods than what LIGO/Virgo detects, and therefore the astrophysical sources are different. 21:22, 11 September 2020 (UTC)

This is a reference to the (possibly apocryphal) Johnny Carson interview of a comedian (possibly Jerry Lewis, possibly Buddy Hackett):

  • Comedian: Go ahead: ask me what is the secret of comedy.
  • Carson: OK, what is the...
  • Comedian: TIMING!

I've looked for the source, and all I can find are retellings of retellings (e.g. https://www.sleuthsayers.org/2013/08/the-immortal-timing-of-elmore-leonard.html ). -- Dtgriscom (talk) 02:35, 12 September 2020 (UTC)

I think the title text is referring to the saying I’m realty that the most important things to consider when buying a house are “location, location, location.” (https://www.realestateabc.com/insights/location.html) 03:34, 12 September 2020 (UTC)

Which is good to know, but leaves some doubt over momentum, momentum and momentum. 08:24, 12 September 2020 (UTC)

The use of curly braces around {location, location, location} might also be a joke. "...using curly braces refers to the character vector that is stored within the string." https://www.sciencedirect.com/topics/engineering/curly-brace I don't understand enough about the topic to be sure. ---- JM

The link points to a specific syntax for one programming language, namely MATLAB. Other languages use {...}, of course, but equally common is (...) or [...]. But importantly it is not a standard math/physics/astronomy notation. In a paper, unless otherwise specified, (x, y, z) is a triple of numbers making a vector whereas {x, y, z} is the set containing x, y, z and nothing else, which might therefore have 1, 2 or 3 elements. If there’s any joke here, it’s that {location, location, location} = {location}.

I've forgotten 110% of what I learned about math, but I thought {length, length, length} (or, equivalently, angle and magnitude) were equally important to a vector in 3-space. 18:22, 12 September 2020 (UTC)

([Coming in three+ years later] A triplet like (1,2,3) can be treated as a vector in 3-space. Consider it the termination of a line segment extending out from the origin (0,0,0). You now have a direction (the way the segment points) and a magnitude (its length)--that is, a vector. Nitpicking (talk) 03:41, 18 November 2023 (UTC)

I don't understand enough about the topic to be sure. ---- breadontoast she also delivers a demonstration on the detection method as a passing gravitational wave will lead to the Radiobursts being slightly out of sync to their expected timing

There is also another joke that vectors only encode direction not location. To get a location a vector must be applied to another location e.g. a vector relative to the origin.

This comic is also reminiscent of this knock-knock joke: "Knock, knock." "Who's there?" "Interrupting cow." "Interrupting co--" "MOO!" 13:11, 18 September 2020 (UTC) delete-if-unhelpful