3086: Globe Safety - Revision history

FaviFake: /* Explanation */

2025-06-16T13:11:02Z

‎Explanation

Sturmovik: /* Explanation */ Tightened up the explanation and added an additional way to interpret the joke.

2025-05-20T17:00:33Z

‎Explanation: Tightened up the explanation and added an additional way to interpret the joke.

162.158.182.128: Added explanation about globe manufacturing

2025-05-16T21:51:11Z

Added explanation about globe manufacturing

172.70.90.4: /* Explanation */ Removed two paragraphs that weren't really explanatory of the comic in any way.

2025-05-12T08:18:06Z

‎Explanation: Removed two paragraphs that weren't really explanatory of the comic in any way.

BunsenH: /* Explanation / maintain the shrink ray! and not any* size

2025-05-11T22:36:40Z

‎Explanation: maintain the shrink ray! and not *any* size

162.158.74.109: /* Explanation */ Given we don't have anything else to distract us, any more, but still need the Incomplete tag...

2025-05-11T18:19:38Z

‎Explanation: Given we don't have anything else to distract us, any more, but still need the Incomplete tag...

FaviFake at 18:06, 11 May 2025

2025-05-11T18:06:12Z

FaviFake: thx!!!

2025-05-11T18:05:32Z

thx!!!

162.158.91.126: Try to clarify and expand on event horizon. The horizon is simply the "surface" of the black hole to external observers. From outside you can't "see anything beneath it". That's how they got the name "black holes".

2025-05-11T16:43:11Z

Try to clarify and expand on event horizon. The horizon is simply the "surface" of the black hole to external observers. From outside you can't "see anything beneath it". That's how they got the name "black holes".

FaviFake: /* Explanation */

2025-05-11T10:35:25Z

‎Explanation

@@ Line 10: / Line 10: @@
 ==Explanation==
 For any given amount of (stationary) mass, a value can be calculated known as the {{w|Schwarzschild radius}}, which denotes the radius of a spherical volume of space. If the mass somehow is compressed into this volume, it becomes so dense that it forms a {{w|black hole}}. The Schwarzschild radius corresponding to the mass of the Earth is about 0.35 inches (roughly 9 mm, or a diameter of 7/10" or 18 mm), meaning that if you could compress the Earth into a ball that small, it would be a black hole. The object at bottom right in the comic, with a triangular warning sign next to it, is a {{w|Black hole#Observation|depiction of a black hole}}.
@@ Line 17: / Line 16: @@
 An alternate interpretation is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size (possibly by removing some of the "empty space" inside atoms). This would, of course, give the most perfect maps; however, for each globe made the Earth's mass would increase by its original amount. In addition it would be impossible to use an Earth-mass globe since something of that density would immediately burrow through the real Earth's crust and proceed to the center of planet.
-The title text doubles down on the joke, suggesting that globes up to 12 inches (30.5 cm) should be banned, due to their extreme gravitational fields. Again, the implication is that representations of Earth would also gain the actual Earth's gravitational properties or would see those properties as a result of actually having an Earth-like mass.
+The title text doubles down on the joke, suggesting that globes up to 12 inches (about 30 centimeters) should be banned, due to their extreme gravitational fields. Again, the implication is that representations of Earth would also gain the actual Earth's gravitational properties or would see those properties as a result of actually having an Earth-like mass.
 ==Transcript==

@@ Line 13: / Line 13: @@
 For any given amount of (stationary) mass, a value can be calculated known as the {{w|Schwarzschild radius}}, which denotes the radius of a spherical volume of space. If the mass somehow is compressed into this volume, it becomes so dense that it forms a {{w|black hole}}. The Schwarzschild radius corresponding to the mass of the Earth is about 0.35 inches (roughly 9 mm, or a diameter of 7/10" or 18 mm), meaning that if you could compress the Earth into a ball that small, it would be a black hole. The object at bottom right in the comic, with a triangular warning sign next to it, is a {{w|Black hole#Observation|depiction of a black hole}}.
-{{w|Globes}}, in this context, are miniature re-creations of planet Earth, used to show its features without any of the [[977: Map Projections|typical problems of a flat map]]. [[Randall]] claims that safety standards are in place to ensure that globes are not manufactured at, below, or even close to the Schwarzschild radius of the Earth. The suggestion is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size. This would, of course, give the most perfect maps; however, for each globe like this put on Earth, the Earth's mass would increase by its original amount. In addition, it would be impractical to make globes this way: such small amounts of matter of this density would [https://www.astronomy.com/science/what-if-a-tablespoonful-of-a-neutron-star-was-brought-to-earth/ immediately explode], vaporizing most or all of the Earth, unless the unknown process that produced the shrinking was maintained.
+{{w|Globes}}, in this context, are miniature re-creations of planet Earth, used to show its features without any of the [[977: Map Projections|typical problems of a flat map]]. [[Randall]] claims that safety standards are in place to ensure that globes are not manufactured at, below, or even close to the Schwarzschild radius of the Earth which implies that the Schwarzschild radius and black hole formation is less a function of mass, but instead based on the ''concept'' of spatial bodies like planets and stars. A scale model of Earth will gain the Schwarzschild radius of the full size Earth because in the XKCD universe Earth-like-things (and presumably representations of other planets and stars) have Schwarzschild radii because that's the way they are.
-There are other practical concerns regarding manufacturing globes of such masses. Since producing one would require the material of the mass of Earth, making one on Earth itself would, by definition, use up all the matter available on our planet (minus the mass of the factory). This means that there is enough material to produce only a single globe, and the potential buyers would be forced to promptly move somewhere else. Such limited supply of the globe would make it prohibitively expensive. Given that potential buyers already would have to incur expenses due to fleeing the apocalypse, the globe is unlikely to find an owner. To make such product more accessible, the manufacturer would have to bring material from outside Earth, harvesting matter from other planets of the Solar system. This redistribution of mass in the Solar system will, however, have an impact on orbits of remaining planets, satellites, asteroids, etc, creating new and unique challenges for human civilization{{Citation needed}}. And, of course, the manufacturer would have to deal with logistical issues of moving planetary masses, both from the sources to the factory and from the factory to buyers.
+An alternate interpretation is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size (possibly by removing some of the "empty space" inside atoms). This would, of course, give the most perfect maps; however, for each globe made the Earth's mass would increase by its original amount. In addition it would be impossible to use an Earth-mass globe since something of that density would immediately burrow through the real Earth's crust and proceed to the center of planet.
-The title text suggests that globes up to 12 inches (30.5 cm) should be banned, due to their extreme density and gravitational field. The surface gravity of an object varies inversely with the square of its radius. Since the globe would have the same mass as the Earth, such a globe would exert massive, catastrophic gravitational forces at its surface. For a 12-inch globe, this would be 1.75 quadrillion times normal Earth gravity. The changes at the Earth's surface caused by these forces would immediately reduce the accuracy of the globe's representation of the area in which it is located. The gravitational effects on objects at a distance would be the same, but adding an Earth mass for each globe would still affect the orbits of other celestial bodies and satellites. However, extreme gravity would exist for Earth-mass globes of any size that globes are commonly used for, so the 12-inch cut-off is no less arbitrary than the 4-inch one.
+The title text doubles down on the joke, suggesting that globes up to 12 inches (30.5 cm) should be banned, due to their extreme gravitational fields. Again, the implication is that representations of Earth would also gain the actual Earth's gravitational properties or would see those properties as a result of actually having an Earth-like mass.
 ==Transcript==

@@ Line 15: / Line 15: @@
 {{w|Globes}}, in this context, are miniature re-creations of planet Earth, used to show its features without any of the [[977: Map Projections|typical problems of a flat map]]. [[Randall]] claims that safety standards are in place to ensure that globes are not manufactured at, below, or even close to the Schwarzschild radius of the Earth. The suggestion is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size. This would, of course, give the most perfect maps; however, for each globe like this put on Earth, the Earth's mass would increase by its original amount. In addition, it would be impractical to make globes this way: such small amounts of matter of this density would [https://www.astronomy.com/science/what-if-a-tablespoonful-of-a-neutron-star-was-brought-to-earth/ immediately explode], vaporizing most or all of the Earth, unless the unknown process that produced the shrinking was maintained.
-The title text suggests that globes up to 12 inches (30.5 cm) should be banned, due to their extreme density and gravitational field. The surface gravity of an object varies inversely with the square of its radius. Since the globe would have the same mass as the Earth, such a globe would exert massive, catastrophic gravitational forces at its surface. For a 12-inch globe, this would be 1.75 quadrillion times normal Earth gravity. The changes at the Earth's surface caused by these forces would immediately reduce the accuracy of the globe's representation of the area in which it is located. The gravitational effects on objects at a distance would be the same, but adding an Earth mass for each globe would still affect the orbits of satellites, other planets, etc. However, extreme gravity would exist for Earth-mass globes of any size that globes are commonly used for, so the 12-inch cut-off is no less arbitrary than the 4-inch one.
+There are other practical concerns regarding manufacturing globes of such masses. Since producing one would require the material of the mass of Earth, making one on Earth itself would, by definition, use up all the matter available on our planet (minus the mass of the factory). This means that there is enough material to produce only a single globe, and the potential buyers would be forced to promptly move somewhere else. Such limited supply of the globe would make it prohibitively expensive. Given that potential buyers already would have to incur expenses due to fleeing the apocalypse, the globe is unlikely to find an owner. To make such product more accessible, the manufacturer would have to bring material from outside Earth, harvesting matter from other planets of the Solar system. This redistribution of mass in the Solar system will, however, have an impact on orbits of remaining planets, satellites, asteroids, etc, creating new and unique challenges for human civilization{{Citation needed}}. And, of course, the manufacturer would have to deal with logistical issues of moving planetary masses, both from the sources to the factory and from the factory to buyers.
 ==Transcript==

@@ Line 11: / Line 11: @@
 ==Explanation==
 {{incomplete|This page was created by an EARTH MASS BOT THE SIZE OF A REGULAR BOT. Don't remove this notice too soon.}}
-For any given amount of (stationary) mass, a value can be calculated known as the {{w|Schwarzschild radius}}, which denotes the radius of a spherical volume of space. If the mass somehow is compressed into this volume, it becomes so dense that it forms a {{w|black hole}}.
+For any given amount of (stationary) mass, a value can be calculated known as the {{w|Schwarzschild radius}}, which denotes the radius of a spherical volume of space. If the mass somehow is compressed into this volume, it becomes so dense that it forms a {{w|black hole}}. The Schwarzschild radius corresponding to the mass of the Earth is about 0.35 inches (roughly 9 mm, or a diameter of 7/10" or 18 mm), meaning that if you could compress the Earth into a ball that small, it would be a black hole. The object at bottom right in the comic, with a triangular warning sign next to it, is a {{w|Black hole#Observation|depiction of a black hole}}.
 {{w|Globes}}, in this context, are miniature re-creations of planet Earth, used to show its features without any of the [[977: Map Projections|typical problems of a flat map]]. [[Randall]] claims that safety standards are in place to ensure that globes are not manufactured at, below, or even close to the Schwarzschild radius of the Earth. The suggestion is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size. This would, of course, give the most perfect maps; however, for each globe like this put on Earth, the Earth's mass would increase by its original amount. In addition, it would be impractical to make globes this way: such small amounts of matter of this density would [https://www.astronomy.com/science/what-if-a-tablespoonful-of-a-neutron-star-was-brought-to-earth/ immediately explode], vaporizing most or all of the Earth, unless the unknown process that produced the shrinking was maintained.

@@ Line 19: / Line 19: @@
 Any arbitrary amount of mass has its corresponding value for its Schwarzschild radius. The Schwarzschild radius corresponding to the mass of the Earth is about 0.35 inches (roughly 9 mm, or a diameter of 7/10" or 18 mm), meaning if you could compress the Earth into a ball that small, it would be a black hole. The object at bottom right in the comic, with a triangular warning sign next to it, is a {{w|Black hole#Observation|depiction of a black hole}}.
-{{w|Globes}}, in this context, are miniature re-creations of planet Earth, used to show its features without any of the [[977: Map Projections|typical problems of a flat map]]. [[Randall]] claims that safety standards are in place to ensure that globes are not manufactured at, below, or even close to the Schwarzschild radius of the Earth. The suggestion is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size. This would, of course, give the most perfect maps; however, for each globe like this put on Earth, the Earth's mass would increase by its original amount, and in addition it would be impractical to make globes this way: such small amounts of matter of this density would [https://www.astronomy.com/science/what-if-a-tablespoonful-of-a-neutron-star-was-brought-to-earth/ immediately explode], vaporizing most or all of the Earth.
+{{w|Globes}}, in this context, are miniature re-creations of planet Earth, used to show its features without any of the [[977: Map Projections|typical problems of a flat map]]. [[Randall]] claims that safety standards are in place to ensure that globes are not manufactured at, below, or even close to the Schwarzschild radius of the Earth. The suggestion is that any globe of the Earth shares the same mass as the Earth and hence the same Schwarzschild radius. Such a globe might be made by creating a literal 1:1 replica of Earth and then shrinking it without distortion until it has the required size. This would, of course, give the most perfect maps; however, for each globe like this put on Earth, the Earth's mass would increase by its original amount. In addition, it would be impractical to make globes this way: such small amounts of matter of this density would [https://www.astronomy.com/science/what-if-a-tablespoonful-of-a-neutron-star-was-brought-to-earth/ immediately explode], vaporizing most or all of the Earth, unless the unknown process that produced the shrinking was maintained.
-The title text suggests that globes up to 12 inches (30.5 cm) should be banned, due to their extreme density and gravitational field. The surface gravity of an object varies inversely with the square of its radius. Since the globe would have the same mass as the Earth, such a globe would exert massive, catastrophic gravitational forces at its surface. For a 12-inch globe, this would be 1.75 quadrillion times normal Earth gravity. The changes at the Earth's surface caused by these forces would immediately reduce the accuracy of the globe's representation of the area in which it is located. The gravitational effects on objects at a distance would be the same, but adding an Earth mass for each globe would still affect the orbits of satellites, other planets, etc. However, extreme gravity would exist for Earth-mass globes of any size, so the 12-inch cut-off is no less arbitrary than the 4-inch one.
+The title text suggests that globes up to 12 inches (30.5 cm) should be banned, due to their extreme density and gravitational field. The surface gravity of an object varies inversely with the square of its radius. Since the globe would have the same mass as the Earth, such a globe would exert massive, catastrophic gravitational forces at its surface. For a 12-inch globe, this would be 1.75 quadrillion times normal Earth gravity. The changes at the Earth's surface caused by these forces would immediately reduce the accuracy of the globe's representation of the area in which it is located. The gravitational effects on objects at a distance would be the same, but adding an Earth mass for each globe would still affect the orbits of satellites, other planets, etc. However, extreme gravity would exist for Earth-mass globes of any size that globes are commonly used for, so the 12-inch cut-off is no less arbitrary than the 4-inch one.
 ==Transcript==

@@ Line 10: / Line 10: @@
 ==Explanation==
-{{incomplete|The first praragraphs might tbe too technical for normal users. Explain the concept of an event horizon, black hole, etc. so people aren't required to click on the Wikipedia link to understand the comic. Don't remove this notice too soon.}}
+{{incomplete|The first paragraphs might be too technical for normal users. Explain the concept of an event horizon, black hole, etc. so people aren't required to click on the Wikipedia link to understand the comic. Don't remove this notice too soon.}}
 For any given amount of (stationary) mass, there is a value known as the {{w|Schwarzschild radius}}, which denotes the radius of a spherical volume of space. If the mass somehow is compressed into this volume, it becomes so dense that it forms a {{w|black hole}}. The newly-born black hole occupies that volume of space—more formally, that Schwarzschild radius then becomes the radius of that black hole's {{w|event horizon}}.

3086: Globe Safety - Revision history

FaviFake: /* Explanation */

Sturmovik: /* Explanation */ Tightened up the explanation and added an additional way to interpret the joke.

162.158.182.128: Added explanation about globe manufacturing

172.70.90.4: /* Explanation */ Removed two paragraphs that weren't really explanatory of the comic in any way.

BunsenH: /* Explanation */ maintain the shrink ray! and not *any* size

162.158.74.109: /* Explanation */ Given we don't have anything else to distract us, any more, but still need the Incomplete tag...

FaviFake at 18:06, 11 May 2025

FaviFake: thx!!!

162.158.91.126: Try to clarify and expand on event horizon. The horizon is simply the "surface" of the black hole to external observers. From outside you can't "see anything beneath it". That's how they got the name "black holes".

FaviFake: /* Explanation */

BunsenH: /* Explanation / maintain the shrink ray! and not any* size