prof-g Profile picture
Sep 19 9 tweets 3 min read Read on X
is there a finite-time singularity in fluids?
(euclidean 3-d euler/navier-stokes, smooth IC)
this is the data we collected at @CRMatematica today... Image
we voted on a scale from 0 to 10 where
0-nope! ==== 5-??? ==== 10-yeah! Image
here's the vote : euler in blue, navier-stokes in red...
but wait...there's more... Image
after voting -- in private! -- we then did a public vote-by-show-of-hands with yes/no/???
(all eyes were on terry tao, sitting in the back...)
then we did a second private vote...
can you guess how terry voted? Image
more data! the same exact question was asked at a meeting in 2007 at the 250th anniversary of the euler equations at a meeting of experts in Aussois, CH
(thanks to Kai Schneider for the data!)
here's what the data was in 2007 Image
if you want to see the change in sentiment over time 2007 => 2024 1st vote => 2024 2nd vote, here's the euler equations... Image
and the same historical trends for navier stokes Image
so what have we learned?
* opinions have drifted more towards singularity
* opinions can change in real-time due to influence by neighbors -- very relevant to information flows...
* MS excel doesn't like indexing from 0 to 10
special thanks to kai cieliebak, @evamirandag , and kai schneider for suggesting and helping to get out the vote! (and for allowing me to conduct this little opinion dynamics experiment...)

• • •

Missing some Tweet in this thread? You can try to force a refresh
 

Keep Current with prof-g

prof-g Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @robertghrist

Sep 6, 2023
1/ yesterday’s thread on the genesis of figures in “Elementary Applied Topology” ended on a cliffhanger: what do all the chapter heading illustrations mean? it’s a puzzle.
get ready for a myth/math mishmash.
2/ the title page & the back cover carry an iconic stylized pomegranate, with some motion induced on what looks like half-a-dozen seeds? hmmm… that reminds me of something… Image
3/ of course, this is a persephone myth – she who was seduced by hades and descended to the underworld. what does that have to do with topology? Image
Read 19 tweets
Sep 4, 2023
1/ in 2009, i began writing a book on topology, meant to be a short introduction to the core concepts, in the context of lots of interesting applications. every idea would be paired with one or more uses, as much outside of mathematics as possible: “applied topology”. Image
2/ i wanted the book to have a lot of pictures – at least one per page on average – and i wanted the pictures to be the exercises. each picture is a puzzle, and if you understand the picture, then you have solved the exercise & understand something. Image
3/ e.g., the snake lemma Image
Read 13 tweets
May 13, 2023
=> new paper w/yuliy baryshnikov <=
"navigating the negative curvature of google maps"
/1 Image
one thing that google maps gets right is the user interface for navigating -- it just feels right to pinch-zoom, scroll, etc.
/2 Image
why is google maps' UI so natural?
hyperbolic geometry!
/3 Image
Read 16 tweets
Mar 2, 2023
1/ this week in multivariable calculus @Penn ...
constrained optimization
2/ this builds on previous investigations into level sets of scalar fields -- a topic for which my students often struggle to grasp the notation & motivation...
a bit of animation can help!
3/ one converts constrained optimization into an unconstrained problem by adding a new variable -- the lagrange multiplier
Read 9 tweets
Feb 20, 2023
1/ this past week in multivariable calculus @Penn
the chain rule & its consequences...
2/ my students all remember how to use the chain rule "by hand", even if writing out / explaining the principle takes more thought. we start off discussing composition and what it means for functions and rates of change...
3/ this is the 1st big payoff for all the linear algebra we've done in class thus far: composition of derivatives as linear transformations corresponds to matrix multiplication
Read 12 tweets
Mar 25, 2022
mathematical art is increasingly important in research & AI is about to revolutionize what can be done... 🧵
i have been doing art & animation for my research & teaching for years & have been convinced that this is the future of imaginative thinking & teaching... but it's hard & has a high learning curve...
all that is about to change.
the following images are created from text prompts via @midjourney
you can sign up for their private beta here: o9q981dirmk.typeform.com/to/zZtF1mVc
Read 16 tweets

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us!

:(