1642: Gravitational Waves

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Gravitational Waves
"That last LinkedIn request set a new record for the most energetic physical event ever observed. Maybe we should respond." "Nah."
Title text: "That last LinkedIn request set a new record for the most energetic physical event ever observed. Maybe we should respond." "Nah."


Ambox notice.png This explanation may be incomplete or incorrect: I've added some detailed explanation. Someone please proofread / review it. Might need some copy-editing.
If you can address this issue, please edit the page! Thanks.

A gravitational wave detector is a device used to measure gravitational waves, small distortions of spacetime that were first predicted by Albert Einstein in 1916. Gravitational waves are ripples in the spacetime fabric itself. This comic came out the day that a direct observation of gravitational waves was publicly announced.

The wikipedia article on gravitational waves describes them well. In simpler/layman's terms, imagine moving a stone through water while it is partly submerged. It will cause waves on the surface of the water as it moves through it. These waves will spread away from the center of disturbance and as they move, they will cause the water molecules to oscilate around their mean positions. Similar waves are created in space-time fabric when two "heavy" celestial bodies interact with each other. If you concentrate on an area of water-surface (analogous to spacetime fabric) far away from the point of disturbance, you can observe that if the wave causes compression in one direction, it'll cause expansion of the fabric in the other. See this page for nice animations (as well as the gravitational waves wiki page).

Note that anything with a mass will cause a gravitational wave. Just as waves created by small stones are tiny in comparison to waves created by huge rocks in water, the waves from humans moving around will be tiny compared to the waves created by celestial bodies. Also, the bigger the body, the stronger the wave and the farther away it will travel. That is why we can only detect gravity waves from heavy bodies like black holes / neutron stars but not from us moving around.

Now consider spacetime fabric as a thin rubber sheet. If you mark any two points on this sheet and stretch/compress it along the axis joining those two points, the relative positions of these points with respect to their neighboring points do not change, but the distance between them changes. LIGO (Laser Interferometer Gravitational-Wave Observatory) is a large-scale physics experiment designed to detect this compression/expansion. Two facts need to be remembered to easily understand the experiment. First, speed of light (c) is a constant and velocity of an object is distance divided by time taken to travel that distance. Second, gravitational waves cause opposite effects (compression and expansion) in directions perpendicular to each other. Putting these two together, at LIGO, an experiment is set up, where two perpendicular long tunnels are constructed with apparatus to emit and detect laser beams. The beam from a laser is split into those two tunnels, then after going through tunnel and back again (a few times) brought together. Tunnel lengths are set up in such a way, that in the absence of gravity waves, interference between the two combined beams causes them to cancel one another out. When the gravitational wave passes through earth, it is expected that the two tunnel lengths will differ due to the expansion/compression effect described above. The interference will be incomplete, and light will not cancel out. This observation can be concluded as "detection of the gravitational wave passing through".

Megan, Cueball, and Ponytail are observing the results from a gravitational wave detector. From the patterns in the gravitational waves detected by this instrument, it might be possible to guess the nature of the event. (e.g. Two bodies with dissimilar masses circling a fixed point, two bodies with equal mass circling each other, collision of two massive bodies, etc.) It might also be possible to triangulate the location of the event. Based on these two facts (the location and nature of the event) we might be able to determine which astronomical bodies caused this event (and the status of those bodies afterwards). Thus, it provides an additional medium to observe the universe in addition to telescopes. This new medium might enable us to observe properties that we couldn't observe with the rest of our observation instruments.

However, the scientists in this comic appear to be receiving spam messages, such as invitations from Linkedin, a mortgage offer, and an announcement of a social meetup, rather than observing astronomical events. There is also a joke because the 'Local Group' is also the technical name for the group of galaxies containing the Milky Way. It is not clear if these so called "events" are causing gravitational waves to be generated or if someone (alien civilization?) is encoding spam messages in gravitational waves. It is plausible that aliens are using gravity waves to encode their messages, since we do something similar with electromagnetic waves to encode and send our messages. Although this it would take an extremely advanced civilization to achieve gravity wave encoding, since it would require them to control orbits and oscillations of super-massive bodies (think at-least on the scale of the Sun, or typically several hundred times bigger than that). The second conclusion (someone is sending spam encoded in gravity waves) seems more plausible since the title text follows this up with a joke that the message senders have gone such a lengths that they caused the most energetic event recorded ever (maybe they blew up few supernovae). One of the receivers is quite impressed with this and suggests that they have to reply to the spam just because the sender has made such an effort to send the message. The other person is not so impressed.

Explanation of observed events

Event Explanation
Black hole merger in Carina (30 M, 30 M)

Possibly legitimate result from the gravitational wave detector. M is a symbol depicting 1 Solar Mass (1.98892×1030 kg). So the statement means that two blackholes, each weighing 30 times our Sun were observed merging in Carina.

Zorlax the Mighty would like to connect on Linkedin

A typical LinkedIn request. Not sure who is Zorlax (the mighty one), but according to title text, he set the record for the most energetic physical event ever observed. He might be looking for a job and this might be him demonstrating (showing-off) his mighty powers instead of simply attaching a resume or filling up his profile. Also, this either means that LinkedIn has now grown outside the Earth, or the Zorlax guy wants to have a job on Earth.

Black hole merger in Orion (20 M, 50 M)

Again a possibly legitimate observation from the gravitational wave detector. It detected blackhole merger of two bodies. One of them is 20 times heavier than Sun, the other is 50 times heavier than the Sun. Both of them are located in Orion.

Mortgage offer from Triangulum Galaxy

Triangulum Galaxy, also known as Pinwheel Galaxy is a spiral galaxy approximately 3 million light-years from Earth. It is not clear if the offer is for a house on Earth or if the advertisers want us to buy house in the Triangulum Galaxy. Either way, unless we humans develop a Wormhole or Faster-than-light travel, we may not be able to take up the offer, even if it is legit.

Zorlax the Mighty would like to connect on Linkedin

Same guy who sent us LinkedIn invite moments ago. May imply that Zorlax is desperate, or may be a jab at LinkedIn's persistence in spamming users with unaccepted connections to view and/or accept them.

Meet lonely singles in the local group tonight!

The space advertisers are using space-GeoIP technology on a galactic scale to send spam. Local Group is the technical term for group of close-by galaxies that also includes Milky Way (our galaxy). There are more than 54 galaxies and few other celestial objects in the local group. Local Group along with several other local groups form Virgo Supercluster. So, it seems that the advertiser might be targetting ads to everyone in the Virgo Supercluster. However, finding "lonely singles" in 54 galaxies within our local group might be easier said than done for humans here on Earth. This kind of spam was previously joked with in 713: GeoIP.


This comic was published on a Thursday, not following the normal publish schedule, to coincide with the announcement of the discovery of a clear gravitational wave signal on February 11, 2016. Gravitational waves were detected through the collision of 2 black holes.


[Cueball, with arms up, is standing behind Megan who has her hands at her mouth, is standing behind Ponytail who sits in front of a large computer console with a big screen a keyboard and several items on the side (lights and labels). Three wires lead away from the console out of the image to the right.]
Megan: The gravitational wave detector works! For the first time, we can listen in on the signals carried by ripples in the fabric of space itself!
[Larger panel with the same setting in the middle, but both Cueball and Megan has taken their arms down. More of the wires from the console can be seen to the right. The computer list six events:]
Computer: Event: Black hole merger in Carina (30 M, 30 M)
Computer: Event: Zorlax the Mighty would like to connect on Linkedin
Computer: Event: Black hole merger in Orion (20 M, 50 M)
Computer: Event: Mortgage offer from Triangulum Galaxy
Computer: Event: Zorlax the Mighty would like to connect on Linkedin
Computer: Event: Meet lonely singles in the local group tonight!

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"Local group" refers to https://en.wikipedia.org/wiki/Local_Group. Lonely singles (black holes?) meeting on a galactic scale would produce another gravitational event. 21:39, 11 February 2016 (UTC) Christoph Berg

Should we add a Trivia section regarding the fact that this comic was posted outside the normal M-W-F schedule? Edo (talk) 23:03, 11 February 2016 (UTC)

Should there be some kind of mention of the possibility (or lack thereof) of artificial gravity waves being used for long-distance communicaiton? --Joshupetersen (talk) 23:41, 11 February 2016 (UTC)

I'm not sure everyone knows what the solar mass symbol looks like. Thaledison (talk) 23:51, 11 February 2016 (UTC)

I think the explanation needs a bit more on the analogy that humans rely heavily on electromagnetic waves for communication. It is reasonable to expect aliens to use gravitational waves for the same as the theoretical basis for encoding messages would likely not need to be change. 08:29, 12 February 2016 (UTC)

Please go ahead and edit it, I'm done for now. I've added lots of stuff. This is the first comic I've tried explaining in full, and it has become quite big. ;-) So far I was only doing small edits here and there... 09:16, 12 February 2016 (UTC)
EDIT - I added a sentence about it. Please do any further edits if you like... 09:24, 12 February 2016 (UTC)
I think this has something to do with |Google Wave or am I overthinking it? 12:11, 12 February 2016 (UTC)

Odd for a massive-object-related comic to not contain a your-mom-joke reference. 12:09, 12 February 2016 (UTC)

"Black hole merger in Carina (30 M☉, 30 M☉)" refers to the public announcement of the first detection ever made of gravity waves from the LIGO-VIRGO experiment. The announcement has been publicly done thursday 11 February 2016, the same day the drawing has been done. This is not a "Possibly legitimate result", but a scientifically proved legitimate result. The drawing has been done in honor to that major scientific first ever observation (which will probably lead to a Nobel Price). -- 15:04, 12 February 2016 (UTC)

I think that the word "merger" is a pun. It is not normally used to describe black hole collisions, but is common in spam messages about stock tips. Not being a native English speaker, I wouldn't attest this, but someone who is might confirm... Mumiemonstret (talk) 11:26, 14 September 2016 (UTC)

"Zorlax is a kid's television gameshow, based on time travel", and "Formed billions of years ago in the earths core, cursed to be but a floating head, gifted with a knowledge of the ages and destined to be the master of time. He is the mighty... ZORLAX!" See here and here. Maybe someone knows this kid's television gameshow. --Dgbrt (talk) 19:21, 12 February 2016 (UTC)

I did not , but I found the reference by googling without spotting your post. It has been included in the explanation in the table. --Kynde (talk) 20:15, 22 February 2016 (UTC)

"One of the receivers is quite impressed with this and suggests that they have to reply to the spam just because the sender has made such an effort to send the message." This line: I actually interpreted the title text as worry rather than being impressed. If a cosmic being is moving around celestial bodies just to make a LinkedIn request and is making increasingly-intense messages, it might be best for the safety of whatever to prevent it from escalating any further. Am I the only one who understood it this way? Jeudi Violist (talk) 19:45, 12 February 2016 (UTC)

Just to be complete: The spam messages could also come from a prankster messing with the computer or some equipment between the experiment and the computer. Of course this is less (if at all) funny than the thought of encoding messages in gravitational waves. (talk) (please sign your comments with ~~~~)

De Speld (dutch "news" site similar to The Onion) reports the gravity waves are the result of natural gas production in Groningen. 14:41, 13 February 2016 (UTC)

I have a somewhat different take on this comic. The "Explanation of observed events" section seems to imply that these messages are directed towards earth. My interpretation is that the team has tapped into some sort of intergalactic internet, where stars are communicating with each other (and, perhaps, looking for other stars to mate with) Sysin (talk) 17:20, 13 February 2016 (UTC)

The event log is presumably a reference to some kind of computer event log, perhaps for network events. I'd assume it's modeled on some obscure Linux thing. I actually came here hoping for an explanation of what type of event log Randall is spoofing. 20:27, 13 February 2016 (UTC)


The Nature article on the discovery mentions that there was a number of "injections" of fake signals in LIGO to test whether the scientists can tell apart real and fake signals. The original signal now considered a confirmation of gravitational waves was first thought to be an injection. This comic might be showing such an experiment with a mixture of real and fake signals.

-- 14:22, 14 February 2016 (UTC)

Is it possible that the "most energetic event is a pun"? As in, "My kid is full of energy," or "That was an energetic party." Mikemk (talk) 08:24, 15 February 2016 (UTC)