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JohannesBorgen Profile picture
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17 Aug, 7 tweets, 3 min read
In 1992, 29k plastic ducks were lost at sea when a cargo ship tumbled in the North Pacific.

Oceanographer Ebbesmeyer tracked them down for many years and their movements helped model oceanic currents – and showed again that solution to the Navier-Stokes equation can be chaotic.
The ducks could pop up almost anywhere (Alaska, Japan, Europe…)
Now Cardona et al have shown something even more extraordinary: no algorithm can tell you if a duck will show up somewhere, at some point.
It is an undecidable problem, in the Gödel sense!

pnas.org/content/118/19…
This result was proved with the Euler equation (simplified version of NS equation) by using a Turing concept: a fluid can simulate a universal Turing machine.
They proved that the halting problem (undecidable) is connected to trajectory calculations!
en.wikipedia.org/wiki/Halting_p…
This is not just fun: it’s also incredibly deep, because in 2014 Terence Tao suggested that if a fluid is Turing complete it can be used to prove the regularity of the Navier Stokes equation.

terrytao.wordpress.com/2014/02/04/fin…
And this is one of the main mathematical problems still unsolved (The Clay Institute offers 1mil if you find the answer).
This problem is crazy: NS is one of the most used equations of physics, with a VERY large range of industrial applications, and we still haven’t proved that it always has a solution ! Maybe the little plastic ducks will finally sort it out for us…
claymath.org/millennium-pro…
Story from this paper, but sorry it's in French and paywalled !
pourlascience.fr/sd/mathematiqu…

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More from @jeuasommenulle

JohannesBorgen Profile picture
30 Aug
There’s something really extraordinary going on in the Irish real estate market.

Quick thread.
The @EBA_News banks’ stress test data allows u to look at the books which have the biggest loss on a country by country basis. Using only IRBA data (more risk sensitive) on can see for example that the riskiest corporate books are in Turkey (here S3 losses in adverse scenario) Image
@EBA_News Looking at retail revolving credit, Mexico is by far the riskiest country. Image
Read 8 tweets
JohannesBorgen Profile picture
26 Aug
You've probably seen the news that SEC & USDA in Brooklyn have launched an investigation against DWS (Deutsche Bank's AM business) for misleading ESG credentials.
On the face of it, it's mostly funny (bit like an ESG^2 story 4 the worst ESG bank of the 2010s) but it's much more.
Why? Because ESG is an unclear, fuzzy, poorly defined field. There are no clear criteria, guidelines, etc.
Anything and everything can be labelled ESG (see my earlier thread.) That's also why it's expanding so much; cheap way of virtue signaling.

BUT (& that's a big change)...
If authorities start prosecuting fake ESG, the whole thing could collapse, precisely because it's fuzzy! If ur not sure what you're doing is OK, but there's only upside, go for it. If you're not sure, but the downside is a criminal investigation, no big institution will do it!
Read 4 tweets
JohannesBorgen Profile picture
18 Aug
Evergrande group chairman Hui Ka Yan stepped down as chairman of the onshore biggest unit (Hengda). There's an official reason for this (no more A-listing) but wait for the two rumored reasons. It's pretty wild.
A) This will trigger debt covenants and start a much needed restructuration of the massive debt

reuters.com/article/china-… Image
B) is even crazier: under Chinese Social Credit rules a top exec of a company that defaults would lose points and lose access to high speed trains, top schools, dating apps (!) etc. So this would be a way to protect his social status and still default !!!

en.wikipedia.org/wiki/Social_Cr…
Read 4 tweets
JohannesBorgen Profile picture
12 Aug
Rules on MREL (minimum requirement for eligible liabilities – eligible = the bond will be screwed if something bad happens) are so complicated, it’s comical.

I won’t go in the details of this nice equation and just mention the farcical situation of UK leverage requirements.
In the UK you have a leverage requirement – like everywhere else. But unlike in the EU (CRR) UK doesn’t count central bank cash in denominator (i.e. exposures). However, the UK MREL also includes a leverage requirement. This is basically 2x the 3.25% leverage requirement + CBR.
But because the UK also implemented the TLAC term sheet, UK banks also have to meet a *second* MREL leverage requirement which is 6.75%+CBR... BUT using CRR (i.e. EU) definitions of leverage, i.e. WITH central bank balances included!
Read 5 tweets
JohannesBorgen Profile picture
9 Jul
Some people were a bit surprised by those kind of headlines... Well, let me explain. Another ESG thread, not the most cheerful one.

reuters.com/business/susta…
True story, on a no name basis for obv reason.

1. Big asset manager has very successful equity fund.

2. Marketing want to add an ESG label to it, to raise even more money.

3. ESG manager says "no, it would change investment process too much, no go."
4. Marketing has none of it. Let's hire a big 4 consultant.

5. Big 4 looks at fund. Produces a report : if u change universe and use this one instead & if you take this data vendor and not the other one, then your fund is ESG compatible Art 8 SFDR with no investment change
Read 4 tweets
JohannesBorgen Profile picture
9 Jul
There was something extremely important in ING’s otherwise rather boring pre-close call yesterday.

They said they would lose 120—200m€ m because of…. Greensill! Why is it important? A quick thread.
ING isn’t even remotely connected to Greensill or Gupta.

They didn’t lend any money, nor invest in a fund, nothing.

No, all ING did was to have a 2.5%-ish market share in Germany. So why did they take a hit?
Simply because Greensill Bank (allegedly) did all sort of frauds and went bust.

But, you argue, ING didn’t lend any money to them!

Sure, but Greensill used one of those new “online deposit gatherers” which optimize the deposit guarantee schemes in the EU.
Read 11 tweets

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