Dr. Rook Bridson
@rookbridson.bsky.social
she/her 🏳️⚧️🏳️🌈
Mathematician in metro Vancouver, working on VFX software in simulation/numerics/geometry. You may know me as the inventor of FLIP for incompressible flow, curl-noise, a very simple fast Poisson disc algorithm, my fluids book, cloth stuff…
Mathematician in metro Vancouver, working on VFX software in simulation/numerics/geometry. You may know me as the inventor of FLIP for incompressible flow, curl-noise, a very simple fast Poisson disc algorithm, my fluids book, cloth stuff…
I realize “Don’t suppress the wiggles! They’re trying to tell you something!” means something very different for me than most people.
It comes from one of those insightful papers where the idea would have stuck with me regardless, but the lede is such perfect writing it really anchors in my memory
It comes from one of those insightful papers where the idea would have stuck with me regardless, but the lede is such perfect writing it really anchors in my memory
November 26, 2025 at 6:10 PM
I realize “Don’t suppress the wiggles! They’re trying to tell you something!” means something very different for me than most people.
It comes from one of those insightful papers where the idea would have stuck with me regardless, but the lede is such perfect writing it really anchors in my memory
It comes from one of those insightful papers where the idea would have stuck with me regardless, but the lede is such perfect writing it really anchors in my memory
I thought I would take a shortcut on a derivation I'm doing for some research, jumping straight to the full 3D model rather than doing the simpler 2D version first,
DESPITE telling people this is always a bad idea (ends up taking more time to get right, misses insights on the way),
DESPITE telling people this is always a bad idea (ends up taking more time to get right, misses insights on the way),
November 19, 2025 at 7:49 PM
I thought I would take a shortcut on a derivation I'm doing for some research, jumping straight to the full 3D model rather than doing the simpler 2D version first,
DESPITE telling people this is always a bad idea (ends up taking more time to get right, misses insights on the way),
DESPITE telling people this is always a bad idea (ends up taking more time to get right, misses insights on the way),
Reposted by Dr. Rook Bridson
Most rapists operate on the premise that they can not only overpower the victim physically, but can do so socially and legally. They count on a system that discounts the voices of victims and only too often cooperates in silencing them...
The Jeffrey Epstein cover-up is an affront to US democracy | Rebecca Solnit
Democracy means a society and system in which everyone’s rights matter. Rapists count on this being untrue – and Trump is proving them right
www.theguardian.com
November 18, 2025 at 3:14 AM
Most rapists operate on the premise that they can not only overpower the victim physically, but can do so socially and legally. They count on a system that discounts the voices of victims and only too often cooperates in silencing them...
Reposted by Dr. Rook Bridson
transness is a gift. i need every trans woman to understand that by nature of their existence they have been blessed with the ability to pluck the strands of fate with their hands if they choose to. it is not always easy and it is not without hardship but every trans woman is capable of greatness.
November 14, 2025 at 1:15 AM
transness is a gift. i need every trans woman to understand that by nature of their existence they have been blessed with the ability to pluck the strands of fate with their hands if they choose to. it is not always easy and it is not without hardship but every trans woman is capable of greatness.
I love how we know the densest possible sphere packing (equal radius, infinite domain) for 1, 2, 3, 8 and 24 dimensions but no others so far. And the 3D result only was proved in 1998, confirmed with formal logic on a computer, but a significant part is way too vast for a human to understand.
November 8, 2025 at 8:25 PM
I love how we know the densest possible sphere packing (equal radius, infinite domain) for 1, 2, 3, 8 and 24 dimensions but no others so far. And the 3D result only was proved in 1998, confirmed with formal logic on a computer, but a significant part is way too vast for a human to understand.
Reposted by Dr. Rook Bridson
Ooops, once again I spilled some aperiodic coffee
October 30, 2025 at 4:16 PM
Ooops, once again I spilled some aperiodic coffee
Once again I find myself deeply annoyed by how a certain subject in physics is presented / taught, and once again deciding I must derive it for myself in a clear and understandable way from first principles.
October 27, 2025 at 5:36 PM
Once again I find myself deeply annoyed by how a certain subject in physics is presented / taught, and once again deciding I must derive it for myself in a clear and understandable way from first principles.
it has been a frustrating few weeks in that even though i’ve had some great research insights and developments, my mental illness has put me in crisis mode much of the time, to put it mildly
(more to the point: i have been suffering in absolute misery for a month, in a year that’s been agony)
(more to the point: i have been suffering in absolute misery for a month, in a year that’s been agony)
October 17, 2025 at 10:56 PM
it has been a frustrating few weeks in that even though i’ve had some great research insights and developments, my mental illness has put me in crisis mode much of the time, to put it mildly
(more to the point: i have been suffering in absolute misery for a month, in a year that’s been agony)
(more to the point: i have been suffering in absolute misery for a month, in a year that’s been agony)
one province over, great
September 19, 2025 at 3:48 AM
one province over, great
Yet again this morning I had a moment where a line of research I pursued a few years ago and never quite brought to fruition suddenly provides me with the tool I need for a different but related problem.
Also, another case of wonderful synergies between numerical linear algebra and PDEs!
Also, another case of wonderful synergies between numerical linear algebra and PDEs!
September 10, 2025 at 7:55 PM
Yet again this morning I had a moment where a line of research I pursued a few years ago and never quite brought to fruition suddenly provides me with the tool I need for a different but related problem.
Also, another case of wonderful synergies between numerical linear algebra and PDEs!
Also, another case of wonderful synergies between numerical linear algebra and PDEs!
one of the hard things (for me!) in doing research for production software is at some point, when you just can’t seem to nail a problem you thought (and still think) is solvable, you have to switch to a pragmatic plan B, the good enough path, despite being aware of its flaws
September 9, 2025 at 3:49 PM
one of the hard things (for me!) in doing research for production software is at some point, when you just can’t seem to nail a problem you thought (and still think) is solvable, you have to switch to a pragmatic plan B, the good enough path, despite being aware of its flaws
I discovered my fluids book is in LibGen (without consent); I just added my name to the list for the lawsuit against Anthropic.
www.anthropiccopyrightsettlement.com/contact
www.anthropiccopyrightsettlement.com/contact
Author and Publisher Contact Information | Bartz, et al. v. Anthropic PBC
www.anthropiccopyrightsettlement.com
September 6, 2025 at 3:23 PM
I discovered my fluids book is in LibGen (without consent); I just added my name to the list for the lawsuit against Anthropic.
www.anthropiccopyrightsettlement.com/contact
www.anthropiccopyrightsettlement.com/contact
Maybe I’m overreacting in deciding against going to SIGGRAPH in the US next year…
*reads today’s news*
aha, never mind
*reads today’s news*
aha, never mind
"Among those detained were South Korean employees on business travel....
"The raid could raise concerns for South Korean companies that are sending personnel to the US and hiring locally."
It comes weeks after Hyundai pledged $26 billion in US investments.
Gift link ⬇️
www.wsj.com/us-news/u-s-...
"The raid could raise concerns for South Korean companies that are sending personnel to the US and hiring locally."
It comes weeks after Hyundai pledged $26 billion in US investments.
Gift link ⬇️
www.wsj.com/us-news/u-s-...
Hundreds Arrested in Immigration Raid at Hyundai Site in Georgia
South Korea said it had expressed concerns to the U.S. about the raid and that it was trying to secure the release of its citizens.
www.wsj.com
September 5, 2025 at 2:48 PM
Maybe I’m overreacting in deciding against going to SIGGRAPH in the US next year…
*reads today’s news*
aha, never mind
*reads today’s news*
aha, never mind
I was just reflecting on how my life as a professor, especially the early pre-tenure days, could have been a lot less stressful and frustrating — and dare I say it, more productive, had I known I had ADHD and autism and adapted to my neurodivergence without inner judgment.
September 3, 2025 at 3:31 PM
I was just reflecting on how my life as a professor, especially the early pre-tenure days, could have been a lot less stressful and frustrating — and dare I say it, more productive, had I known I had ADHD and autism and adapted to my neurodivergence without inner judgment.
Reposted by Dr. Rook Bridson
As it's still valid, presumably if I don't keep following it, I am also breaking the law and subject to arrest.
The law of the land simultaneously requires me to be both a man and a woman and if I do either then I am breaking the law and subject to arrest. (11/13)
The law of the land simultaneously requires me to be both a man and a woman and if I do either then I am breaking the law and subject to arrest. (11/13)
August 29, 2025 at 11:56 AM
As it's still valid, presumably if I don't keep following it, I am also breaking the law and subject to arrest.
The law of the land simultaneously requires me to be both a man and a woman and if I do either then I am breaking the law and subject to arrest. (11/13)
The law of the land simultaneously requires me to be both a man and a woman and if I do either then I am breaking the law and subject to arrest. (11/13)
I just discovered the "weak Galerkin" method, as in I now know it exists and it caught my eye, but now I need to actually find readable descriptions of it to start wrapping my head around it.
One lifetime never seems enough for all the things I want to learn and do!
One lifetime never seems enough for all the things I want to learn and do!
August 28, 2025 at 2:08 PM
I just discovered the "weak Galerkin" method, as in I now know it exists and it caught my eye, but now I need to actually find readable descriptions of it to start wrapping my head around it.
One lifetime never seems enough for all the things I want to learn and do!
One lifetime never seems enough for all the things I want to learn and do!
I designed a big chunk of numerica code to ship in product, this time with an accompanying proof it must be stable (modulo how exact a big linear solve is, but even there with good reason to think we will be fine)
except I explicitly made one simplifying assumption I was pretty sure would be fine…
except I explicitly made one simplifying assumption I was pretty sure would be fine…
August 27, 2025 at 10:44 PM
I designed a big chunk of numerica code to ship in product, this time with an accompanying proof it must be stable (modulo how exact a big linear solve is, but even there with good reason to think we will be fine)
except I explicitly made one simplifying assumption I was pretty sure would be fine…
except I explicitly made one simplifying assumption I was pretty sure would be fine…
Yet again today my phone reminded me I had a meeting at 11 well in advance, and at 10:53 the math got interesting and I realized I needed a different approach than I thought originally, and suddenly time skipped forward to 11:07 and I was embarrassingly late to the call 😂
August 26, 2025 at 12:14 AM
Yet again today my phone reminded me I had a meeting at 11 well in advance, and at 10:53 the math got interesting and I realized I needed a different approach than I thought originally, and suddenly time skipped forward to 11:07 and I was embarrassingly late to the call 😂
A thing I have been meaning to write up and elaborate on is how I both approach math/algorithms as an artist more than as a scientist — and likewise approach creating art with the same exploration and problem-solving mindset as I apply in math.
But today is not that day 😀
But today is not that day 😀
August 25, 2025 at 12:12 AM
A thing I have been meaning to write up and elaborate on is how I both approach math/algorithms as an artist more than as a scientist — and likewise approach creating art with the same exploration and problem-solving mindset as I apply in math.
But today is not that day 😀
But today is not that day 😀
Trying out a new pen, uniball signo 0.5mm, so far loving it. It is refillable, but my record at not breaking plastic pens isn’t great so we shall see…
August 24, 2025 at 4:24 PM
Trying out a new pen, uniball signo 0.5mm, so far loving it. It is refillable, but my record at not breaking plastic pens isn’t great so we shall see…
Today I was reminded of a cool fact that at first glance looks decidedly bizarre.
Midpoint quadrature — split your interval into n equal subintervals, add up the (smooth!) integrand evaluated at the midpoints and multiply by the width of a subinterval — is of course only second order accurate, 🧵
Midpoint quadrature — split your interval into n equal subintervals, add up the (smooth!) integrand evaluated at the midpoints and multiply by the width of a subinterval — is of course only second order accurate, 🧵
August 21, 2025 at 8:35 PM
Today I was reminded of a cool fact that at first glance looks decidedly bizarre.
Midpoint quadrature — split your interval into n equal subintervals, add up the (smooth!) integrand evaluated at the midpoints and multiply by the width of a subinterval — is of course only second order accurate, 🧵
Midpoint quadrature — split your interval into n equal subintervals, add up the (smooth!) integrand evaluated at the midpoints and multiply by the width of a subinterval — is of course only second order accurate, 🧵
Life hack: when you have a definite integral that you _know_ must be a rational number with a smallish denominator, sometimes i just run midpoint quadrature with n=100,000 and rounding to the nearest such rational 😂
August 21, 2025 at 8:17 PM
Life hack: when you have a definite integral that you _know_ must be a rational number with a smallish denominator, sometimes i just run midpoint quadrature with n=100,000 and rounding to the nearest such rational 😂
The guide I wish I had had when I decided to get started on hormones a little over two years ago!
August 20, 2025 at 10:51 PM
The guide I wish I had had when I decided to get started on hormones a little over two years ago!
Sometimes research work is developing a clever new methodology to let you prove that the earlier great idea you had cannot possibly work. I suppose yay for negative results that let me avoid wasting more time on a dead end, but also, all that math to arrive back at square one, sighhhhhhhhh
August 19, 2025 at 9:38 PM
Sometimes research work is developing a clever new methodology to let you prove that the earlier great idea you had cannot possibly work. I suppose yay for negative results that let me avoid wasting more time on a dead end, but also, all that math to arrive back at square one, sighhhhhhhhh
Back to work after back-to-back vacation in Italy and then SIGGRAPH. Excited to revive a longstanding research idea I had that could bear fruit in product, but also hopeful the break will mean I can crack some problems in fluids I was stuck on just before.
August 18, 2025 at 4:00 PM
Back to work after back-to-back vacation in Italy and then SIGGRAPH. Excited to revive a longstanding research idea I had that could bear fruit in product, but also hopeful the break will mean I can crack some problems in fluids I was stuck on just before.