Happy World Quantum Day to those who do and do not celebrate.

@ionica Already several meetings about Quantum done today.

But, About Post-Quantum Crypotograhy.

This was my favorite.
https://pcsi.nl/nl/projecten/pcsi-pqc-workgroup/

@harld one of our PhD students gave a talk about the quantum Levine hat problem, which was lovely.

@ionica Ik zit meer in de hoek van cryptografie en dan is de stap naar Quantum best klein.

En dan bij Radboud University.
https://bacc.cs.ru.nl/2026/ (zit in adviesraad)

Applied Cryptography Course 2026

The Radboud University is organising a course in Applied Cryptography in collaboration with the Dutch Banking Association (NVB). The course is aimed at personnel of the banking industry, the government, and industry, and teaches the basics of cryptography required to correctly apply and assess it.

For those that observe this holiday things collapse immidiately...
@ionica I'm afraid that by posting this, you have made us aware of World Quantum Day and we are now forced to choose between celebrating or not. You're collapsing so many quantum waves with this post!
@ionica How does one 'observe' World Quantum Day?
@lnkvt @ionica Through a double slit board?
@lnkvt @ionica you can observe quantum day but then you don’t know when it happens.
@MyLittleMetroid @lnkvt @ionica you might know when but then it becomes impossible to know where.
@ky @lnkvt @ionica This is why all the Quantum day parties are always just a bunch of people who happened to be around.
@lnkvt @ionica Presumably World Quantum Day is every day until someone looks for it, and then it is that particular day?
@ionica I''ll check my cat to see if I'm celebrating or not.
World Quantum Day - Wikipedia

@ionica And to the ones that don't know if they celebrate it or not at this present moment

@ionica

I started a standing wave of applause…
but it decohered instantly.

@ionica

Schrödinger got me on a string today.

@ionica At last, a holiday specifically designed to make cats nervous.
@ionica Actually no one knows which day is Quantum Day until we observe it.
@chrisp
So if someone somewhere is observing it each day...
Then ever day is quantum day?????   
@ionica
@lynfox @ionica Yes. But also, when we observe today as Quantum Day does that mean the previous days were not Quantum Day?

@chrisp @lynfox @ionica

It's fundamentally impossible to determine the precise time and location of any Quantum Day party.

It's all Flash Mobs! ❣️

@ionica
I see / didn’t see what you did there.
@ionica I might approve of this. Maybe.

@ionica

I would celebrate except I have some previous entanglements

@ionica

Apparently there's a Schrödinger day, but no one dares to check.

@ionica En gefeliciteerd met "licht is een golf" Christiaan Huygens.
@ednl @ionica "licht is een golf" snap ik nog, maar quantum
....is voor mij te moeilijk.......
@ionica you changed the day by observing it!
@ionica
I thought it was yesterday