iiinova — where your digital self keeps evolving

Philipp Wacker @phkwacker.bsky.social · 26/09/2026

Little acts of rebellion are what keep up my spirits

Textbook: "... it is easy (good exercise) to check that ...", but I crossed out the word "easy"

Philipp Wacker @phkwacker.bsky.social · 02/09/2026

I'm starting to mourn the (anticipated) loss of a generation of creators, teachers, inventors, and all kinds of skilled people that will not choose their calling because GenAI has made them redundant (taking advantage of unpaid unattributed human labour that came before them).

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Philipp Wacker @phkwacker.bsky.social · 25/08/2026

I've been thinking recently about how indigenous ways of teaching and learning could point us towards how to solve the current crisis of mathematics. My reach on Bluesky isn't exactly great so I'm yelling this at the void, but I'll just put down my thoughts here, since it lets me organise them.

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Philipp Wacker @phkwacker.bsky.social · 24/08/2026

Make a band bigger Metallicona

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Philipp Wacker @phkwacker.bsky.social · 21/08/2026

I'm sure my kids enjoyed the brief typography lecture I gave them when they asked me what went wrong here

Back of popcorn bag, text has all "fi" and "fl" missing (replaced by a square placeholder)

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Philipp Wacker @phkwacker.bsky.social · 28/06/2026

Reading The Joy Of Abstraction by Eugenia Cheng and I love this sentence: "The point of an equation is to use the sense in which two sides are the same to pivot between the senses in which they aren't."

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Philipp Wacker @phkwacker.bsky.social · 28/06/2026

"Problem solving is just a means to an end. The core payout of pure mathematics is the neuroplastic elevation of our worldview, and we can’t get there by copy-pasting the result." This really resonated with me.

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Philipp Wacker @phkwacker.bsky.social · 28/05/2026

I took a book out from the library and unconsciously started skipping over whole pages, getting increasingly annoyed. At some point I reflected on what was making me do that and now I'm 99% sure the book is largely written by genAI. Completely unreadable garbage

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Philipp Wacker @phkwacker.bsky.social · 27/05/2026

@visualpde.com Is such an awesome website. Explaining geometric Brownian motion in a lecture tomorrow, and this tool here will help me illustrate the corresponding forward Kolmogorov equation: visualpde.com/sim?mini=JOD...

visualpde.com

Interactive simulation | VisualPDE

An interactive simulation of a partial differential equation, live in your browser with VisualPDE.

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Philipp Wacker @phkwacker.bsky.social · 20/05/2026

How did I not know before that Schrödinger was a pedophile?

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Philipp Wacker @phkwacker.bsky.social · 19/05/2026

I'm just so proud of my students in my Random Processes class. I essentially told them "do something that is connected to probability and work on it in a group, I don't care what it is" (and gave them a list of possible ideas). They ended up doing so much cool stuff: Modelling Paper Scissors Rock

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Philipp Wacker @phkwacker.bsky.social · 19/05/2026

My library hold came through! Have been looking forward to reading The Edge of Space-Time by @chanda.blacksky.app for a long time!

My hand is holding a copy of "The Edge of space-time" by Dr. Chanda Prescod-Weinstein

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Philipp Wacker @phkwacker.bsky.social · 06/05/2026

Reading @miabirdsong.bsky.social's "How we show up" and it's just really fantastic. So many cool things I need to try out.

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Reposted by Philipp Wacker

Jacquelyn Gill @jacquelyngill.bsky.social · 25/04/2026

The attack on education in the US is not new, but the slow fuse that arguably started with Reagan is now setting off detonations across K-12 and higher education that are going to be incredibly difficult to walk back if we don’t treat this like the urgent crisis it is.

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Philipp Wacker @phkwacker.bsky.social · 11/03/2026

We are supposed to spell λ "Lamda"? My life is a lie!

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Philipp Wacker @phkwacker.bsky.social · 09/03/2026

Conservative parties and resulting governments are, like, just bad. This is true for every country that I've ever spent time in.

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Philipp Wacker @phkwacker.bsky.social · 14/02/2026

Folks! Use the Atkinson Hyperlegible Font in LaTeX with \usepackage[sfdefault]{atkinson}. Helps your readers and looks gorgeous!

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Philipp Wacker @phkwacker.bsky.social · 10/02/2026

A surprisingly fun game to play with your kids on long car trips: Count up, but only numbers that you see on the way. A 1 on a number plate. A 2 on a phone number on an ad, a 3 on a bus stop. Gets trickier once you're in double digits and beyond.

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Philipp Wacker @phkwacker.bsky.social · 02/02/2026

When I have to use a journal's LaTeX template for a paper slowly chip down the number of new compile errors from about 500 down to 0 (hopefully!), I feel like one of these lumberjacks carving out a grizzly bear with a chainsaw.

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Philipp Wacker @phkwacker.bsky.social · 29/01/2026

After rewatching Zootopia I'm now convinced it should be considered an adaptation of Terry Pratchett's Nightwatch canon. The plot of both is like this: A young and naive person from the country (Carrot Ironfoundersson in NW, a literal bunny with a carrot farming background in Zootopia) joins the

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Philipp Wacker @phkwacker.bsky.social · 26/01/2026

I want to redesign the assessment of my 2nd year probability and random processes course in a way that is more robust against GenAI. So far I just had assignments with exercises that can now trivially be solved by LLMs out there. Any ideas? So far I'm thinking:

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Philipp Wacker @phkwacker.bsky.social · 18/01/2026

One of my favourite things about my job as a dad: Pretending to be annoyed when the kids sneakily steal and munch all the cut up cucumbers and tomatoes that I "need for other things"

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Philipp Wacker @phkwacker.bsky.social · 15/12/2025

Funded PhD (3 yrs): Bayesian Optimal Experimental Design Univ. of Canterbury, Christchurch, New Zealand 🇳🇿 | Marsden Fund Math & computation for Bayesian OED in inverse problems (optimal control, filtering). Women & others underrepresented in maths/stats in particular encouraged to apply.

tinyurl.com

Funded PhD Position: Bayesian Optimal Experimental Design

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Philipp Wacker @phkwacker.bsky.social · 07/12/2025

Am I the only one who is annoyed that we don't have a special symbol for the product integral? The \Sigma becomes and \int when we take the limit in the (Riemann) integral approximation, but the \Pi just stays a \Pi when we make a product integral!

$A two-by-two panel showing (top left) a Riemann integral sum approximation \sum_{i=1}^N f(x_i)\Delta x_i, (top right, and connected with an arrow saying "limit") a definite integral \int_a^b f(x) dx. Bottom left: A finite product approximation of the product integral \sum_{i=1}^N (1 + f(x_i)\Delta x_i), connecting to bottom right with an arrow to a product integral \prod_a^b (1+f(x) dx)$

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Philipp Wacker @phkwacker.bsky.social · 14/10/2025

This is brutal. Without even mentioning all the science funding cuts youtu.be/h-yjkAXxnMA?...

youtu.be

Honest Government Ad | Visit New Zealand!

YouTube video by thejuicemedia

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Philipp Wacker @phkwacker.bsky.social · 10/10/2025

I am sure he will take it well when he won't have won the Nobel Peace Prize in four hours.

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Philipp Wacker @phkwacker.bsky.social · 16/09/2025

Who decided that the literally most vanilla dessert flavor that everyone can agree on is a very specific South American orchid? Runner-up: Rotten tree seeds, from a very specific South American tree.

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Philipp Wacker @phkwacker.bsky.social · 23/08/2025

Declined an invitation to a Minisymposium at a conference I usually like to go to solely because the location is in the US.

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Philipp Wacker @phkwacker.bsky.social · 20/08/2025

As a mapping from C to C, z \mapsto z is holomorphic, but z \mapsto \bar z is not? How do you explain reconcile this with the assumption of an all-powerful and benign god, theists?

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Philipp Wacker @phkwacker.bsky.social · 29/07/2025

The last few weeks I have been using our fantastic UC makerspace (with its 3d printers, soldering iron, and tools) to print the OpenFlexure Project Manual Microscope. Kudos to @openflexure.bsky.social for an amazing open source design. Looking forward to looking at pond water and earth critters.

3d-printed microscope in black, gray, and light blue. Shows a power source consisting of 3 AA batteries and badly soldered connections.

A hair follicle under magnification. Looks like a black-ish twisted worm with four edges (?)

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Philipp Wacker @phkwacker.bsky.social · 21/07/2025

This might be the perfect way to phrase it

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Philipp Wacker @phkwacker.bsky.social · 17/07/2025

Next time I run out of symbols/letters for a paper, I will take my cue from the ridiculous stuff economists seem to be get away with. This is all from a single publication.

(grave) accented beta, boldly generalising the concept of pitch accent from vowels to consonants.

A hebrew Dalet, and a strike-out capital, no-serif D. The strike out comes directly after an inline "/", leading to two diagonal lines with very different meaning. I would have given bonus points for combining Dalet with a capital Gamma but it seems the authors chickened out at the last time.

vertically flipped capital Omega ("Agemo"?), superscript g

word-final version of lower case sigma, multiplied by "normal" lower-case sigma (squared), subscript capital Xi (cursive!)

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Philipp Wacker @phkwacker.bsky.social · 03/06/2025

What is the correct metre for the "woof, woof, woof, woof" part of "Who let the dogs out"? This has been on my mind too much recently, so here's my attempt. You're welcome, internet. (or am I wrong?)

four bits of "woof", on ONE-e-and-e-two-e-AND-e-three-e-AND-e-four-E-and-e

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Philipp Wacker @phkwacker.bsky.social · 14/05/2025

the sound that you're hearing is global maths research grinding to a halt

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Philipp Wacker @phkwacker.bsky.social · 13/05/2025

New dating platform for tradies just dropped

Photo of "Pro-strength Liquid PLUMR clog destroyer gel"

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Philipp Wacker @phkwacker.bsky.social · 08/05/2025

Maybe not surprising, but today I found out that a Zoom call with participants from Germany, Australia, New Zealand, and the US is hard to schedule.

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Philipp Wacker @phkwacker.bsky.social · 01/05/2025

I do want to encourage everyone to follow Auschwitz Memorial in order to get regular reminders on their timeline of what fascism invariably leads to.

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Philipp Wacker @phkwacker.bsky.social · 27/04/2025

One of the most fun things about reading comic books in languages you are trying to learn is that you learn "comic speak", i.e. other languages equivalents of "kaboom" and the like.

A cartoon panel of an old Victorian (?) home with lots of forest and shrubbery in the background. In the sky above the house the words هاهاها، هاهاها hang in the air, transliterating hearty laughter that can be heard outside

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Philipp Wacker @phkwacker.bsky.social · 22/04/2025

I found a super cool example for an affine space (as contrasted to a vector space) in real life: A piano keyboard (or more abstractly, musical notes in the western music tradition). You cannot add two notes (points) to get a new points, because you will get a chord, which is something else entirely.

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Philipp Wacker @phkwacker.bsky.social · 20/04/2025

Finally time for baking over the holidays. Rye/wheat

Two long-ish loaves of bread, dark brown color, with diagonal cuts

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Philipp Wacker @phkwacker.bsky.social · 24/03/2025

Something cool I understood this week: The Kullback-Leibler divergence between two multivariate Gaussian distributions has a closed form solution. The term with the means somehow makes sense: Penalise a covariance-weighted squared distance between the respective means. But all these matrix terms?

$Formula for KL divergence between two Gaussians N_0 and N_1 {\displaystyle D_{\text{KL}}\left({\mathcal {N}}_{0}\parallel {\mathcal {N}}_{1}\right)={\frac {1}{2}}\left(\operatorname {tr} \left(\Sigma _{1}^{-1}\Sigma _{0}\right)-k+\left(\mu _{1}-\mu _{0}\right)^{\mathsf {T}}\Sigma _{1}^{-1}\left(\mu _{1}-\mu _{0}\right)+\ln \left({\frac {\det \Sigma _{1}}{\det \Sigma _{0}}}\right)\right).}$

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Philipp Wacker @phkwacker.bsky.social · 23/03/2025

What's happening with the indices here? Why are they not aligned?

$PDF LaTeX output of $Y_i Y_i^\top$. The heights of the two indices i are not aligned.$

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Philipp Wacker @phkwacker.bsky.social · 20/03/2025

I like all the songs in both Moana and Moana 2, but it has been bugging me that in "How far I'll go", she sings "Everybody on this island has a role on this island", rhyming "island" with "island". Is this just lazy writing or am I missing some hidden metaphor or something here?

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