#xkcd No. 3077
Date: 2025-4-16
Title: de Sitter
Alt text: Our anti-de Sitter club is small at the moment, but I've started corresponding with the conformal field theory people.
https://xkcd.com/3077/
xkcd
![Description:
Single panel xkcd comic. A door with a sign taped to it that reads "20TH CENTURY DUTCH PHYSICIST WILLEM DE SITTER IS NOT WELCOME HERE".
Transcript:
[Image shows a door with a sign taped to it.]
Sign on door:
20TH CENTURY
DUTCH PHYSICIST
WILLEM DE SITTER
IS NOT
WELCOME HERE
Below the image:
MY HOUSE IS AN ANTI-DE SITTER SPACE.](/proxy/post_attachment/682545/674052cc6b.png "Description:
Single panel xkcd comic. A door with a sign taped to it that reads \"20TH CENTURY DUTCH PHYSICIST WILLEM DE SITTER IS NOT WELCOME HERE\".
Transcript:
[Image shows a door with a sign taped to it.]
Sign on door:
20TH CENTURY
DUTCH PHYSICIST
WILLEM DE SITTER
IS NOT
WELCOME HERE
Below the image:
MY HOUSE IS AN ANTI-DE SITTER SPACE.")
#xkcd No. 3078
Date: 2025-4-18
Title: Anchor Screws
Alt text: The biggest expense was installing the mantle ducts to keep the carbonate-silicate cycle operating.
https://xkcd.com/3078/
#xkcd No. 3086
Date: 2025-5-7
Title: Globe Safety
Alt text: Frankly, given their extreme gravitational fields and general instability, even 12-inch globes should probably be banned.
https://xkcd.com/3086/
![Description:
Single panel xkcd comic. A desktop globe is shown with "4 inches minimum" text. Below, smaller globe turns into a black hole with an alert symbol.
Transcript:
REMEMBER:
K4 INCHES
MINIMUM
[Arrow indicating 7/10 inches transforming Earth into a blackhole with an alert sign overhead.]
THE EARTH'S SCHWARZSCHILD
RADIUS IS ABOUT 0.35 INCHES,
WHICH IS WHY SAFETY REGULATIONS
REQUIRE DESKTOP GLOBES TO BE
AT LEAST 4 INCHES IN DIAMETER.](/proxy/post_attachment/703617/9d753755c1.png "Description:
Single panel xkcd comic. A desktop globe is shown with \"4 inches minimum\" text. Below, smaller globe turns into a black hole with an alert symbol.
Transcript:
REMEMBER:
K4 INCHES
MINIMUM
[Arrow indicating 7/10 inches transforming Earth into a blackhole with an alert sign overhead.]
THE EARTH'S SCHWARZSCHILD
RADIUS IS ABOUT 0.35 INCHES,
WHICH IS WHY SAFETY REGULATIONS
REQUIRE DESKTOP GLOBES TO BE
AT LEAST 4 INCHES IN DIAMETER.")
#xkcd No. 3093
Date: 2025-5-23
Title: Drafting
Alt text: A 5% efficiency gain at the cost of a 99% efficiency loss
https://xkcd.com/3093/
#xkcd No. 3087
Date: 2025-5-9
Title: Pascal's Law
Alt text: Reductio ad absurdum fails when reality is absurd.
https://xkcd.com/3087/
![Description: A single panel xkcd comic shows a physics lecture with stick figures. A teacher points to a diagram of a hydraulic press while students sit at desks.
Transcript:
NO, THAT CAN'T BE RIGHT.
IF HYDROSTATIC PRESSURE WORKED THAT WAY,
THEN YOU COULD USE IT TO MAKE MACHINES
THAT EXERT NEAR-INFINITE FORCE.
AND ANCIENT PEOPLE COULD HAVE DEMOLISHED
ENTIRE MOUNTAINS JUST BY DRILLING SMALL
TUNNELS AND FILLING THEM WITH WATER.
[Diagram of hydraulic press. On the left side, a small cylinder with a piston pushing down on it. The cylinder is connected to a larger cylinder on the right side by a pipe. The right cylinder has a platform on top with a figure next to a bag labeled "1000" with an arrow pointing to the top of the platform.]
WHEN I FIRST LEARNED ABOUT PASCAL'S LAW, I TRIED
TO DISPROVE IT BY SHOWING THAT IT WOULD LEAD TO
ABSURD CONSEQUENCES, BUT IT TURNS OUT HYDRAULIC
PRESSES AND RUINA MONTIUM ARE BOTH REAL THINGS.](/proxy/post_attachment/705093/72a68c32c9.png "Description: A single panel xkcd comic shows a physics lecture with stick figures. A teacher points to a diagram of a hydraulic press while students sit at desks.
Transcript:
NO, THAT CAN'T BE RIGHT.
IF HYDROSTATIC PRESSURE WORKED THAT WAY,
THEN YOU COULD USE IT TO MAKE MACHINES
THAT EXERT NEAR-INFINITE FORCE.
AND ANCIENT PEOPLE COULD HAVE DEMOLISHED
ENTIRE MOUNTAINS JUST BY DRILLING SMALL
TUNNELS AND FILLING THEM WITH WATER.
[Diagram of hydraulic press. On the left side, a small cylinder with a piston pushing down on it. The cylinder is connected to a larger cylinder on the right side by a pipe. The right cylinder has a platform on top with a figure next to a bag labeled \"1000\" with an arrow pointing to the top of the platform.]
WHEN I FIRST LEARNED ABOUT PASCAL'S LAW, I TRIED
TO DISPROVE IT BY SHOWING THAT IT WOULD LEAD TO
ABSURD CONSEQUENCES, BUT IT TURNS OUT HYDRAULIC
PRESSES AND RUINA MONTIUM ARE BOTH REAL THINGS.")
#xkcd No. 3079
Date: 2025-4-21
Title: Air Fact
Alt text: 'Wow, that must be why you swallow so many of them per year!' 'No, that's spiders. You swallow WAY more ants.'
https://xkcd.com/3079/
#xkcd No. 3088
Date: 2025-5-12
Title: Deposition
Alt text: P.S. If you have time travel, come to my birthday party Saturday!
https://xkcd.com/3088/
![Description:
Four panel xkcd comic. Stick figures in panels 1-3. The last shows aliens in spacecraft excavating rocks. Text indicates passage of 100 million years.
Transcript:
Panel 1:
WHAT ARE YOU DOING?
THIS RIVER EMPTIES
ONTO A PASSIVE
CONTINENTAL MARGIN.
Panel 2:
IF I CHISEL NOTES ONTO
THESE ROCKS AND THROW
THEM INTO THE SEA, THEY
MIGHT BE INCORPORATED
INTO SOME SHALE CLIFF
IN THE DISTANT FUTURE.
Panel 3:
[Two stick figures, one throwing rocks into the sea]
PLOP
Panel 4:
100 MILLION
YEARS LATER...
???
??
THIS
BEDROCK
INSPECTED
BY NO. 5](/proxy/post_attachment/708089/b25c83f5cb.png "Description:
Four panel xkcd comic. Stick figures in panels 1-3. The last shows aliens in spacecraft excavating rocks. Text indicates passage of 100 million years.
Transcript:
Panel 1:
WHAT ARE YOU DOING?
THIS RIVER EMPTIES
ONTO A PASSIVE
CONTINENTAL MARGIN.
Panel 2:
IF I CHISEL NOTES ONTO
THESE ROCKS AND THROW
THEM INTO THE SEA, THEY
MIGHT BE INCORPORATED
INTO SOME SHALE CLIFF
IN THE DISTANT FUTURE.
Panel 3:
[Two stick figures, one throwing rocks into the sea]
PLOP
Panel 4:
100 MILLION
YEARS LATER...
???
??
THIS
BEDROCK
INSPECTED
BY NO. 5")
#xkcd No. 3095
Date: 2025-5-28
Title: Archaea
Alt text: Under the two-domain system, anyone who punches you is technically an Archaean pathogen.
https://xkcd.com/3095/
#xkcd No. 3097
Date: 2025-6-2
Title: Bridge Types
Alt text: Pontoon bridges are just linear open-sided waterbeds.
https://xkcd.com/3097/
#xkcd No. 3096
Date: 2025-5-30
Title: Check Engine
Alt text: They say it's probably safe to keep orbiting for a while, but if it stays on or starts flashing we might have to call someone.
https://xkcd.com/3096/
![Description:
A single panel shows a close-up view of the sun as a large orange circle against a black background. A black rectangle with a yellow "check engine" light symbol is visible on the sun's surface, resembling a sunspot.
Transcript:
[Image of the sun with a "Check Engine" symbol on its surface.]
THIS NEW SUNSPOT CLUSTER HAS RAISED
CONCERN AMONG ASTRONOMERS](/proxy/post_attachment/726074/9704c9c6f1.png "Description:
A single panel shows a close-up view of the sun as a large orange circle against a black background. A black rectangle with a yellow \"check engine\" light symbol is visible on the sun's surface, resembling a sunspot.
Transcript:
[Image of the sun with a \"Check Engine\" symbol on its surface.]
THIS NEW SUNSPOT CLUSTER HAS RAISED
CONCERN AMONG ASTRONOMERS")
#xkcd No. 3103
Date: 2025-6-16
Title: Exoplanet System
Alt text: Sure, this exoplanet we discovered may seem hostile to life, but our calculations suggest it's actually in the accretion disc's habitable zone.
https://xkcd.com/3103/
#xkcd No. 3092
Date: 2025-5-21
Title: Baker's Units
Alt text: 169 is a baker's gross.
https://xkcd.com/3092/
![Description: A single panel shows examples of "baker's units," including groups of objects, a ruler, time, a geometric shape, a date, musical notation, stick figures, and a flag.
Transcript: BAKER'S UNITS
OOOOOOOOOOOO—BAKER'S DOZEN
[Image of a ruler marked with increments]—BAKER'S FOOT
1:00 PM—BAKER'S NOON
[Image of a dodecahedron]—BAKER'S DODECAHEDRON
JANUARY 31ST—BAKER'S NEW YEAR'S EVE
[Image of a musical staff with notes]—BAKER'S OCTAVE
[Row of stick figures]—BAKER'S JURY
[Image of the EU flag]—BAKER'S EU FLAG
ALUMINUM—BAKER'S MAGNESIUM](/proxy/post_attachment/717281/b72a196747.png "Description: A single panel shows examples of \"baker's units,\" including groups of objects, a ruler, time, a geometric shape, a date, musical notation, stick figures, and a flag.
Transcript: BAKER'S UNITS
OOOOOOOOOOOO—BAKER'S DOZEN
[Image of a ruler marked with increments]—BAKER'S FOOT
1:00 PM—BAKER'S NOON
[Image of a dodecahedron]—BAKER'S DODECAHEDRON
JANUARY 31ST—BAKER'S NEW YEAR'S EVE
[Image of a musical staff with notes]—BAKER'S OCTAVE
[Row of stick figures]—BAKER'S JURY
[Image of the EU flag]—BAKER'S EU FLAG
ALUMINUM—BAKER'S MAGNESIUM")
#xkcd No. 3098
Date: 2025-6-4
Title: Trojan Horse
Alt text: Ultimately, history would imperfectly record the story of the Foal of Troy.
https://xkcd.com/3098/
![Description:
Four-panel comic strip show stick figures reacting to a horse, then a smaller horse appearing from a horse.
Transcript:
Panel 1:
WHEN THE GREEKS DEPARTED, THEY LEFT BEHIND A HORSE AS A GIFT.
[Four stick figures stand on a wall overlooking a horse on the ground.]
Panel 2:
WE TOOK IT AS A GESTURE OF PEACE, BUT IT CARRIED A SECRET PAYLOAD.
[A stick figure and a stick figure with a ponytail stand near a large horse.]
Panel 3:
ONE NIGHT, FROM WITHIN THE HORSE, ANOTHER, SMALLER HORSE EMERGED!
[A small horse stands next to a large horse.]
Panel 4:
OUR GUARDS HAVE BEEN UNABLE TO DETERMINE THE INNER HORSE'S OBJECTIVE, BUT IT HAS BEGUN TO SHOW AN INTEREST IN OUR OATS.
An Attack on Troy's Food Supply!
HOW DARE THEY!?
[A stick figure shrugs. Two small asterisks are connected by curving lines to the text "HOW DARE THEY!?"]](/proxy/post_attachment/731478/20542b16c4.png "Description:
Four-panel comic strip show stick figures reacting to a horse, then a smaller horse appearing from a horse.
Transcript:
Panel 1:
WHEN THE GREEKS DEPARTED, THEY LEFT BEHIND A HORSE AS A GIFT.
[Four stick figures stand on a wall overlooking a horse on the ground.]
Panel 2:
WE TOOK IT AS A GESTURE OF PEACE, BUT IT CARRIED A SECRET PAYLOAD.
[A stick figure and a stick figure with a ponytail stand near a large horse.]
Panel 3:
ONE NIGHT, FROM WITHIN THE HORSE, ANOTHER, SMALLER HORSE EMERGED!
[A small horse stands next to a large horse.]
Panel 4:
OUR GUARDS HAVE BEEN UNABLE TO DETERMINE THE INNER HORSE'S OBJECTIVE, BUT IT HAS BEGUN TO SHOW AN INTEREST IN OUR OATS.
An Attack on Troy's Food Supply!
HOW DARE THEY!?
[A stick figure shrugs. Two small asterisks are connected by curving lines to the text \"HOW DARE THEY!?\"]")
#xkcd No. 3101
Date: 2025-6-11
Title: Good Science
Alt text: If you think curiosity without rigor is bad, you should see rigor without curiosity.
https://xkcd.com/3101/
![Description:
A four-panel xkcd comic strip about good science. Stick figures are shown interacting in a classroom or similar setting.
Transcript:
Panel 1:
I'M SUPPOSED TO GIVE YOU THE TOOLS TO DO GOOD SCIENCE.
[A stick figure stands next to a list on a podium.]
Panel 2:
BUT WHAT ARE THOSE TOOLS?
METHODOLOGY IS HARD AND THERE ARE SO MANY WAYS TO GET INCORRECT RESULTS.
WHAT IS THE MAGIC INGREDIENT THAT MAKES FOR GOOD SCIENCE?
[A teacher figure stands in front of two students sitting at desks.]
Panel 3:
TO FIGURE IT OUT, I RAN A REGRESSION WITH ALL THE FACTORS PEOPLE SAY ARE IMPORTANT:
OUTCOME VARIABLE:
• CORRECT SCIENTIFIC RESULTS
PREDICTORS:
• COLLABORATION
• SKEPTICISM OF OTHERS' CLAIMS
• QUESTIONING YOUR OWN BELIEFS
• TRYING TO FALSIFY HYPOTHESES
• CHECKING CITATIONS
• STATISTICAL RIGOR
• BLINDED ANALYSIS
• FINANCIAL DISCLOSURE
• OPEN DATA
[A student's head is shown looking at a list.]
Panel 4:
THE REGRESSION SAYS TWO INGREDIENTS ARE THE MOST CRUCIAL:
1) GENUINE CURIOSITY ABOUT THE ANSWER TO A QUESTION, AND
2) AMMONIUM HYDROXIDE
WAIT, WHY DID AMMONIA SCORE SO HIGH? HOW DID IT EVEN GET ON THE LIST?
...AND NOW YOU'RE DOING GOOD SCIENCE!
[The student reading the list reacts with confusion. One of the students from Panel 2 is shown reacting with raised arms, while the other student is seated at their desk.]](/proxy/post_attachment/738515/bed8503754.png "Description:
A four-panel xkcd comic strip about good science. Stick figures are shown interacting in a classroom or similar setting.
Transcript:
Panel 1:
I'M SUPPOSED TO GIVE YOU THE TOOLS TO DO GOOD SCIENCE.
[A stick figure stands next to a list on a podium.]
Panel 2:
BUT WHAT ARE THOSE TOOLS?
METHODOLOGY IS HARD AND THERE ARE SO MANY WAYS TO GET INCORRECT RESULTS.
WHAT IS THE MAGIC INGREDIENT THAT MAKES FOR GOOD SCIENCE?
[A teacher figure stands in front of two students sitting at desks.]
Panel 3:
TO FIGURE IT OUT, I RAN A REGRESSION WITH ALL THE FACTORS PEOPLE SAY ARE IMPORTANT:
OUTCOME VARIABLE:
• CORRECT SCIENTIFIC RESULTS
PREDICTORS:
• COLLABORATION
• SKEPTICISM OF OTHERS' CLAIMS
• QUESTIONING YOUR OWN BELIEFS
• TRYING TO FALSIFY HYPOTHESES
• CHECKING CITATIONS
• STATISTICAL RIGOR
• BLINDED ANALYSIS
• FINANCIAL DISCLOSURE
• OPEN DATA
[A student's head is shown looking at a list.]
Panel 4:
THE REGRESSION SAYS TWO INGREDIENTS ARE THE MOST CRUCIAL:
1) GENUINE CURIOSITY ABOUT THE ANSWER TO A QUESTION, AND
2) AMMONIUM HYDROXIDE
WAIT, WHY DID AMMONIA SCORE SO HIGH? HOW DID IT EVEN GET ON THE LIST?
...AND NOW YOU'RE DOING GOOD SCIENCE!
[The student reading the list reacts with confusion. One of the students from Panel 2 is shown reacting with raised arms, while the other student is seated at their desk.]")
#xkcd No. 3099
Date: 2025-6-6
Title: Neighbor-Source Heat Pump
Alt text: The installation of the pipes on the inside of the insulation can be challenging, especially when the neighbor could come home at any minute.
https://xkcd.com/3099/
#xkcd No. 3100
Date: 2025-6-9
Title: Alert Sound
Alt text: With a good battery, the device can easily last for 5 or 10 years, although the walls probably won't.
https://xkcd.com/3100/
![Description:
A single panel comic. A stick figure person is sitting at a desk with a laptop, covering their ears and yelling. A sound effect is shown nearby.
Transcript:
[Sound effect of "boop!"]
AAAAA!
I HEARD IT AGAIN!
WHERE IS THAT COMING FROM!?
IT TURNS OUT LIVING WELL IS ONLY THE SECOND-BEST REVENGE. the BEST REVENGE IS MAKING A TINY HOLE IN SOMEONE'S WALL AND DROPPING IN A BATTERY-POWERED CAPSULE THAT, EVERY 6-12 HOURS, PLAYS THE ALERT SOUND OF A USB DEVICE CONNECTING.](/proxy/post_attachment/736096/399564eb4e.png "Description:
A single panel comic. A stick figure person is sitting at a desk with a laptop, covering their ears and yelling. A sound effect is shown nearby.
Transcript:
[Sound effect of \"boop!\"]
AAAAA!
I HEARD IT AGAIN!
WHERE IS THAT COMING FROM!?
IT TURNS OUT LIVING WELL IS ONLY THE SECOND-BEST REVENGE. the BEST REVENGE IS MAKING A TINY HOLE IN SOMEONE'S WALL AND DROPPING IN A BATTERY-POWERED CAPSULE THAT, EVERY 6-12 HOURS, PLAYS THE ALERT SOUND OF A USB DEVICE CONNECTING.")
#xkcd No. 3105
Date: 2025-6-20
Title: Interoperability
Alt text: We're getting a lot of complaints from commuters who were routed onto a coaster, but the theme park patrons who spent hours stuck on an intercity line are also not happy.
https://xkcd.com/3105/
#xkcd No. 3106
Date: 2025-6-23
Title: Farads
Alt text: 'This HAZMAT container contains radioactive material with activity of one becquerel.' 'So, like, a single banana slice?'
https://xkcd.com/3106/
![Description: A four-panel xkcd comic features a stick figure, a woman with short dark hair, and a stick figure wearing a fedora. They interact with various objects that are exactly "one" of a unit, with reactions changing from casual to alarmed.
Transcript:
Panel 1:
Voice 1: THIS STICK IS ONE METER LONG.
Woman: COOL.
Man in fedora: THAT'S A NICE STICK.
[A stick figure holds up a stick.]
Panel 2:
Voice 1: THIS ROCK WEIGHS ONE POUND.
Woman: I'D BELIEVE IT.
Man in fedora: LOOKS LIKE A NORMAL ROCK.
[A stick figure holds up a small rock.]
Panel 3:
Voice 1: THIS BATTERY IS ONE VOLT.
Woman: SEEMS FINE.
Man in fedora: MIGHT NEED A RECHARGE.
[A stick figure holds up a small battery.]
Panel 4:
Voice 1: THIS CAPACITOR IS ONE FARAD.
Woman: AAAAA! BE CAREFUL!!
Man in fedora: PUT IT DOWN!!
[A stick figure holds up a small capacitor, while the woman recoils and the man in the fedora yells in alarm.]](/proxy/post_attachment/750791/e94c5cd1a0.png "Description: A four-panel xkcd comic features a stick figure, a woman with short dark hair, and a stick figure wearing a fedora. They interact with various objects that are exactly \"one\" of a unit, with reactions changing from casual to alarmed.
Transcript:
Panel 1:
Voice 1: THIS STICK IS ONE METER LONG.
Woman: COOL.
Man in fedora: THAT'S A NICE STICK.
[A stick figure holds up a stick.]
Panel 2:
Voice 1: THIS ROCK WEIGHS ONE POUND.
Woman: I'D BELIEVE IT.
Man in fedora: LOOKS LIKE A NORMAL ROCK.
[A stick figure holds up a small rock.]
Panel 3:
Voice 1: THIS BATTERY IS ONE VOLT.
Woman: SEEMS FINE.
Man in fedora: MIGHT NEED A RECHARGE.
[A stick figure holds up a small battery.]
Panel 4:
Voice 1: THIS CAPACITOR IS ONE FARAD.
Woman: AAAAA! BE CAREFUL!!
Man in fedora: PUT IT DOWN!!
[A stick figure holds up a small capacitor, while the woman recoils and the man in the fedora yells in alarm.]")
#xkcd No. 3112
Date: 2025-7-7
Title: Geology Murder
Alt text: After determining that his body was full of pipes carrying iron-rich fluid, our current theory is that the dagger-shaped object precipitated within the wound.
https://xkcd.com/3112/
#xkcd No. 3104
Date: 2025-6-18
Title: Tukey
Alt text: Numbers can be tricky. On the day of my 110th birthday, I'll be one day younger than John Tukey was on his.
https://xkcd.com/3104/
#xkcd No. 3108
Date: 2025-6-27
Title: Laser Danger
Alt text: To combat the threat, many airlines are installing wing-mounted spray bottles.
https://xkcd.com/3108/
![Description: A three-panel xkcd comic. The first panel shows two stick figures talking. The second panel depicts an airplane flying with a green laser pointing up from the ground, hitting the plane. The third panel shows a cat latching onto the side of the same airplane, which is now tilted.
Transcript:
Panel 1:
SHINING LASER POINTERS AT PLANES IS A FEDERAL CRIME. IT'S INCREDIBLY DANGEROUS.
OH, BECAUSE IT CAN BLIND THE PILOT?
THAT'S ONE REASON...
Panel 2:
[An airplane flies through the air, with a green laser beam hitting its underside from below. The laser originates from a small dot on the ground]
Panel 3:
[A cat is shown clinging to the side of the airplane, which is now tilted sideways. A dashed line indicates the path the cat took to jump onto the plane.]](/proxy/post_attachment/753416/5a9b98ce7f.png "Description: A three-panel xkcd comic. The first panel shows two stick figures talking. The second panel depicts an airplane flying with a green laser pointing up from the ground, hitting the plane. The third panel shows a cat latching onto the side of the same airplane, which is now tilted.
Transcript:
Panel 1:
SHINING LASER POINTERS AT PLANES IS A FEDERAL CRIME. IT'S INCREDIBLY DANGEROUS.
OH, BECAUSE IT CAN BLIND THE PILOT?
THAT'S ONE REASON...
Panel 2:
[An airplane flies through the air, with a green laser beam hitting its underside from below. The laser originates from a small dot on the ground]
Panel 3:
[A cat is shown clinging to the side of the airplane, which is now tilted sideways. A dashed line indicates the path the cat took to jump onto the plane.]")
#xkcd No. 3109
Date: 2025-6-30
Title: Dehumidifier
Alt text: It's important for devices to have internet connectivity so the manufacturer can patch remote exploits.
https://xkcd.com/3109/
#xkcd No. 3110
Date: 2025-7-2
Title: Global Ranking
Alt text: Starting a meta-leaderboard for tracking who holds the record for ranking behind the most distinct people on an online leaderboard.
https://xkcd.com/3110/
#xkcd No. 3111
Date: 2025-7-4
Title: Artificial Gravity
Alt text: Low gravity can cause bone loss, so we're pleased to report that, since we initiated capsule motion, the number of bones in each crew member has been steadily increasing.
https://xkcd.com/3111/
