soaproot
@soaproot.sfba.social.ap.brid.gy
Also known.as: Jim Kingdon. Interested in: formal mathematics, software development, dance (especially country-western and #MorrisDancing, but many kinds), plants […]
[bridged from https://sfba.social/@soaproot on the fediverse by https://fed.brid.gy/ ]
[bridged from https://sfba.social/@soaproot on the fediverse by https://fed.brid.gy/ ]
RE: https://tech.lgbt/@libsteve/115611585076070209
Anyone on #librarians or #bookstodon who knows something about Library of Congress classification willing to take a few questions from @libsteve ?
Anyone on #librarians or #bookstodon who knows something about Library of Congress classification willing to take a few questions from @libsteve ?
tech.lgbt
November 26, 2025 at 6:00 PM
RE: https://tech.lgbt/@libsteve/115611585076070209
Anyone on #librarians or #bookstodon who knows something about Library of Congress classification willing to take a few questions from @libsteve ?
Anyone on #librarians or #bookstodon who knows something about Library of Congress classification willing to take a few questions from @libsteve ?
Reposted by soaproot
Fediverse admin, moderator and community manager efforts resolve the overwhelming majority of issues before most are even aware of them.
Let's hold moderation to high standards, while also extending the respect and support these volunteers deserve.
Send your mod team some love today. They’ve […]
Let's hold moderation to high standards, while also extending the respect and support these volunteers deserve.
Send your mod team some love today. They’ve […]
Original post on mastodon.iftas.org
mastodon.iftas.org
November 4, 2025 at 1:39 PM
Fediverse admin, moderator and community manager efforts resolve the overwhelming majority of issues before most are even aware of them.
Let's hold moderation to high standards, while also extending the respect and support these volunteers deserve.
Send your mod team some love today. They’ve […]
Let's hold moderation to high standards, while also extending the respect and support these volunteers deserve.
Send your mod team some love today. They’ve […]
Metazooa
Become an evolutionary detective to find the Mystery Animal!
metazooa.com
October 24, 2025 at 2:13 AM
🐗 Animal #776 🐃
I figured it out in 5 guesses!
🟥🟧🟩🟩🟩
🔥 2 | Avg. Guesses: 5.8
https://metazooa.com
#metazooa
I figured it out in 5 guesses!
🟥🟧🟩🟩🟩
🔥 2 | Avg. Guesses: 5.8
https://metazooa.com
#metazooa
Metazooa
Become an evolutionary detective to find the Mystery Animal!
metazooa.com
September 14, 2025 at 3:08 PM
🐗 Animal #776 🐃
I figured it out in 5 guesses!
🟥🟧🟩🟩🟩
🔥 2 | Avg. Guesses: 5.8
https://metazooa.com
#metazooa
I figured it out in 5 guesses!
🟥🟧🟩🟩🟩
🔥 2 | Avg. Guesses: 5.8
https://metazooa.com
#metazooa
Reposted by soaproot
@llewelly @soaproot important to note that fossil pseudofeces is very different from the equally entertaining topic of pseudo fossil feces https://theplosblog.plos.org/2014/07/pseudo-poo-glitters-isnt-fecal-gold/
theplosblog.plos.org
September 6, 2025 at 3:22 PM
@llewelly @soaproot important to note that fossil pseudofeces is very different from the equally entertaining topic of pseudo fossil feces https://theplosblog.plos.org/2014/07/pseudo-poo-glitters-isnt-fecal-gold/
At the California Science Center museum and just found some new (to me) #clamfacts . According to Wikipedia this species lives at thousands of meters below the ocean's surface and gets nutrition from bacteria on its gills which can process hydrogen sulfide from deep sea vents.
August 21, 2025 at 8:16 PM
At the California Science Center museum and just found some new (to me) #clamfacts . According to Wikipedia this species lives at thousands of meters below the ocean's surface and gets nutrition from bacteria on its gills which can process hydrogen sulfide from deep sea vents.
I've posted about this a few times but let me try to do so more clearly. How do we, in #constructivemathematics , show that a set is countably infinite (that is, there is a bijection between our set and the set of natural numbers)? There's a theorem for this which is elegant and also handles […]
Original post on sfba.social
sfba.social
August 11, 2025 at 7:33 PM
I've posted about this a few times but let me try to do so more clearly. How do we, in #constructivemathematics , show that a set is countably infinite (that is, there is a bijection between our set and the set of natural numbers)? There's a theorem for this which is elegant and also handles […]
Reposted by soaproot
Y'all continue to be the most interested in clam facts by far of any socials I share on. I really admire ya. Stay curious!
August 1, 2025 at 9:24 PM
Y'all continue to be the most interested in clam facts by far of any socials I share on. I really admire ya. Stay curious!
Reposted by soaproot
I'm among those that have heard that a tsunami can be modelled as a soliton, but the authors of this article think that some important tsunamis of the past were not solitons and that you can just use the shallow water theory.
Solitons and Tsunamis […]
Solitons and Tsunamis […]
Original post on mathstodon.xyz
mathstodon.xyz
July 30, 2025 at 8:57 AM
I'm among those that have heard that a tsunami can be modelled as a soliton, but the authors of this article think that some important tsunamis of the past were not solitons and that you can just use the shallow water theory.
Solitons and Tsunamis […]
Solitons and Tsunamis […]
I'm writing about nonincreasing sequences of zeroes and ones. So you could have all zeroes, all ones, a one followed by zeroes, two ones followed by zeroes, etc. (Here a sequence is a function from ω, the set of natural numbers, to { 0 , 1 }). How many such sequences are there?
1/n
1/n
July 17, 2025 at 10:57 PM
I'm writing about nonincreasing sequences of zeroes and ones. So you could have all zeroes, all ones, a one followed by zeroes, two ones followed by zeroes, etc. (Here a sequence is a function from ω, the set of natural numbers, to { 0 , 1 }). How many such sequences are there?
1/n
1/n
Reposted by soaproot
Given the axioms of IZF set theory, define real numbers as Dedekind cuts, the complex exponential as the limit of an infinite series, and sine and cosine in terms of the complex exponential. Define τ to be the smallest positive real whose cosine is one. Define π to be the smallest positive real […]
Original post on sfba.social
sfba.social
June 28, 2024 at 1:55 PM
Given the axioms of IZF set theory, define real numbers as Dedekind cuts, the complex exponential as the limit of an infinite series, and sine and cosine in terms of the complex exponential. Define τ to be the smallest positive real whose cosine is one. Define π to be the smallest positive real […]
Reposted by soaproot
A counting problem on input size \\(N\\) where for all \\(N \geq 43632\\), we now know the answer \\(t(N)\\) satisfies
\\[ N/3 \leq t(N) \leq N/e \\]
and moreover, for all \\(N\neq 56\\), \\(t(N) \geq \lfloor N/3.5\rfloor\\), and the upper bound actually holds for all \\(N\neq 1,2,4\\) […]
\\[ N/3 \leq t(N) \leq N/e \\]
and moreover, for all \\(N\neq 56\\), \\(t(N) \geq \lfloor N/3.5\rfloor\\), and the upper bound actually holds for all \\(N\neq 1,2,4\\) […]
Original post on mathstodon.xyz
mathstodon.xyz
June 19, 2025 at 10:29 AM
A counting problem on input size \\(N\\) where for all \\(N \geq 43632\\), we now know the answer \\(t(N)\\) satisfies
\\[ N/3 \leq t(N) \leq N/e \\]
and moreover, for all \\(N\neq 56\\), \\(t(N) \geq \lfloor N/3.5\rfloor\\), and the upper bound actually holds for all \\(N\neq 1,2,4\\) […]
\\[ N/3 \leq t(N) \leq N/e \\]
and moreover, for all \\(N\neq 56\\), \\(t(N) \geq \lfloor N/3.5\rfloor\\), and the upper bound actually holds for all \\(N\neq 1,2,4\\) […]
Reposted by soaproot
In the ocean, if you build it, they will come. By "they" I mean the entire ecosystem! From oil rigs to sunken ships, life loves to settle on our stuff. Offshore mussel farming takes advantage of this phenomenon. Floating rope rigs are used to host mussels to maturity, which are fed entirely from […]
Original post on scicomm.xyz
scicomm.xyz
June 9, 2025 at 4:32 AM
In the ocean, if you build it, they will come. By "they" I mean the entire ecosystem! From oil rigs to sunken ships, life loves to settle on our stuff. Offshore mussel farming takes advantage of this phenomenon. Floating rope rigs are used to host mussels to maturity, which are fed entirely from […]
Reposted by soaproot
So, the Dutch cabinet just dissolved itself. It lasted much longer than anticipated and created more damage than what can be repaired in just a few weeks. Let’s hope for a more stable and more sensible government in the future. Latest polls still see the populists that have a history of running […]
Original post on mastodon.social
mastodon.social
June 3, 2025 at 8:16 AM
So, the Dutch cabinet just dissolved itself. It lasted much longer than anticipated and created more damage than what can be repaired in just a few weeks. Let’s hope for a more stable and more sensible government in the future. Latest polls still see the populists that have a history of running […]
Reposted by soaproot
This is a problem that all those clever AI/ML people should try to bring down the numbers in:
"Consider the class of Diophantine equations with at most 11 unknowns and
at most degree \\(1.63 \cdot 10^{63}\\). Hilbert’s Tenth Problem is unsolvable for this class: There is no algorithm that can […]
"Consider the class of Diophantine equations with at most 11 unknowns and
at most degree \\(1.63 \cdot 10^{63}\\). Hilbert’s Tenth Problem is unsolvable for this class: There is no algorithm that can […]
Original post on mathstodon.xyz
mathstodon.xyz
May 24, 2025 at 10:59 AM
This is a problem that all those clever AI/ML people should try to bring down the numbers in:
"Consider the class of Diophantine equations with at most 11 unknowns and
at most degree \\(1.63 \cdot 10^{63}\\). Hilbert’s Tenth Problem is unsolvable for this class: There is no algorithm that can […]
"Consider the class of Diophantine equations with at most 11 unknowns and
at most degree \\(1.63 \cdot 10^{63}\\). Hilbert’s Tenth Problem is unsolvable for this class: There is no algorithm that can […]
Reposted by soaproot
How do we compute a function f : (ℕ → ℕ) → ℕ abstractly?
This question goes back to Brouwer in the early 20th century, and was investigated by many people, including Kleene.
Think of the input α : ℕ → ℕ of the function f as a sequence of natural numbers.
So out of a sequence of natural […]
This question goes back to Brouwer in the early 20th century, and was investigated by many people, including Kleene.
Think of the input α : ℕ → ℕ of the function f as a sequence of natural numbers.
So out of a sequence of natural […]
Original post on mathstodon.xyz
mathstodon.xyz
May 20, 2025 at 8:13 PM
How do we compute a function f : (ℕ → ℕ) → ℕ abstractly?
This question goes back to Brouwer in the early 20th century, and was investigated by many people, including Kleene.
Think of the input α : ℕ → ℕ of the function f as a sequence of natural numbers.
So out of a sequence of natural […]
This question goes back to Brouwer in the early 20th century, and was investigated by many people, including Kleene.
Think of the input α : ℕ → ℕ of the function f as a sequence of natural numbers.
So out of a sequence of natural […]
The San Bruno BART train station seems to have (at some point in the past) declared war on pigeons. The pigeons are winning. (Present but not pictured: lots more pigeons)
May 18, 2025 at 5:13 PM
The San Bruno BART train station seems to have (at some point in the past) declared war on pigeons. The pigeons are winning. (Present but not pictured: lots more pigeons)
For those not on Bluesky, @xenaproject wrote there:
Let G be a magma (i.e a set equipped with a multiplication and no further axioms). Can you prove that if ∀ x y z, x = x(y((zx)y)) then ∀ x y z, x = x(y(z(xz)))? You can use a theorem prover, a language model, a SAT or SMT solver or even pencil […]
Let G be a magma (i.e a set equipped with a multiplication and no further axioms). Can you prove that if ∀ x y z, x = x(y((zx)y)) then ∀ x y z, x = x(y(z(xz)))? You can use a theorem prover, a language model, a SAT or SMT solver or even pencil […]
Original post on sfba.social
sfba.social
May 17, 2025 at 5:23 PM
For those not on Bluesky, @xenaproject wrote there:
Let G be a magma (i.e a set equipped with a multiplication and no further axioms). Can you prove that if ∀ x y z, x = x(y((zx)y)) then ∀ x y z, x = x(y(z(xz)))? You can use a theorem prover, a language model, a SAT or SMT solver or even pencil […]
Let G be a magma (i.e a set equipped with a multiplication and no further axioms). Can you prove that if ∀ x y z, x = x(y((zx)y)) then ∀ x y z, x = x(y(z(xz)))? You can use a theorem prover, a language model, a SAT or SMT solver or even pencil […]
Have you ever tried to start a book club at work? Did it lose steam around chapter 3 of the second book (if you even got that far)? Mine did.
Start a blog post club! See https://jkingdon2000.blogspot.com/2025/05/blog-post-club.html for further details and suggestions about how to run one.
Start a blog post club! See https://jkingdon2000.blogspot.com/2025/05/blog-post-club.html for further details and suggestions about how to run one.
Blog Post Club
Have you ever tried to start a book club at work? Did it lose steam around chapter 3 of the second book (if you even got that far)? Mine did.
But how should we learn things from our co-workers? How should we keep in touch with what is going on in the industry? How can we apply ideas to our own company?
Our blog post club format evolved as much as was designed, but has worked for us. Throughout the period between the meetings, people propose blog posts for discussion (a public slack channel works well but I could imagine a wiki page, shared public document, or anything which makes it easy to add items). At the meeting (once every two weeks for us), the facilitator asks everyone to vote on which blog post they'd like to discuss and puts the posts in order roughly from most votes to fewest. Someone presents the blog post (most often the person who posted it). The presentation is a summary of what is in the post plus discussion (roughly 5 to 15 minutes per blog post), and we typically get to about three to five blog posts per meeting.
As with any discussion oriented meeting, facilitating it can be harder than it looks, but the focus on blog posts organizes the meeting. Agenda? Based on the posts we have and the votes. Digression onto a tangent? Often handled by saying "that's a great topic, why don't you find a blog post on that subject and post it in the channel for the next meeting". Disagreement between meeting participants? Sometimes can be handled by turning the focus to "the author of this post apparently would have said X". People didn't prepare for the meeting? We don't expect people to prepare and one thing that keeps this manageable is that the ideal blog post isn't too long to read/skim during the meeting itself.
Have you tried this at work? How did it go? Any tips which might help other people start a blog post club at their job?
jkingdon2000.blogspot.com
May 12, 2025 at 5:01 PM
Have you ever tried to start a book club at work? Did it lose steam around chapter 3 of the second book (if you even got that far)? Mine did.
Start a blog post club! See https://jkingdon2000.blogspot.com/2025/05/blog-post-club.html for further details and suggestions about how to run one.
Start a blog post club! See https://jkingdon2000.blogspot.com/2025/05/blog-post-club.html for further details and suggestions about how to run one.
May 1, 2025 at 1:11 PM
Reposted by soaproot
One only has to diss constructive math to get upvotes by mathematicians. https://mathoverflow.net/a/491478/1176
Why is it so difficult to define constructive cardinality?
Consider Frege's cardinality and HoTT set-truncation cardinality, both of which can be well-defined in constructive theory (as SetoidTT and CubicalTT, respectively). Why don’t we regard them as well
mathoverflow.net
April 23, 2025 at 8:49 PM
One only has to diss constructive math to get upvotes by mathematicians. https://mathoverflow.net/a/491478/1176
Reposted by soaproot
@dantheclamman Wait, you buried the lead (all the way into the alt text)! Brood their young‽ Baby clams crawling out of the womb (if I'm allowed to call it that)‽ Every time I think I have enough #clamfacts I become thirsty for more.
April 2, 2025 at 1:47 PM
@dantheclamman Wait, you buried the lead (all the way into the alt text)! Brood their young‽ Baby clams crawling out of the womb (if I'm allowed to call it that)‽ Every time I think I have enough #clamfacts I become thirsty for more.
Saw some scaffolding in New York and all I could think of is <a href="https://bsky.app/profile/did:plc:orw2ozs2ujhagv7jp4iv5552" class="hover:underline text-blue-600 dark:text-sky-400 no-card-link" target="_blank" rel="noopener" data-link="bsky-mention">@marklevinenyc.bsky.social @marklevinenyc and his efforts to keep scaffolding from being permascaffolding. Of note: there seems to be some work going on here!
April 1, 2025 at 7:34 PM
Saw some scaffolding in New York and all I could think of is <a href="https://bsky.app/profile/did:plc:orw2ozs2ujhagv7jp4iv5552" class="hover:underline text-blue-600 dark:text-sky-400 no-card-link" target="_blank" rel="noopener" data-link="bsky-mention">@marklevinenyc.bsky.social @marklevinenyc and his efforts to keep scaffolding from being permascaffolding. Of note: there seems to be some work going on here!