iiinova — where your digital self keeps evolving

Niko @nikosarcevic.com · 01/08/2026

Not sure if I ever shared but I’m obsessed with lighting (hello, photons! 😆) I have so many lamps, plugins etc it’s embarrassing at this point. But in any case I just bought a new lamp and it’s so freaking gorgeous I caaaaaant

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Niko @nikosarcevic.com · 24/07/2026

I’m deeply honored to share I am now a builder within LSST DESC! This means I have made significant contributions to the collaboration I am in position to be added to every publication from now on (with certain caveats)

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Niko @nikosarcevic.com · 11/06/2026

Fresh on the @arxiv 💪 Check out how baryons and nonlinear galaxy bias (and scales) impact the 3x2pt analysis in the LSST scenario arxiv.org/abs/2606.10679

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Niko @nikosarcevic.com · 10/06/2026

I’m doing science physics

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Niko @nikosarcevic.com · 09/06/2026

I’ve been obsessed with Langewiesche’s writing since I discovered his @theatlantic.com articles. If someone had told me I’d be into a book about shipping and maritime stuff, man… He was such a master of narrative nonfiction that he can make any subject fascinating.

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Niko @nikosarcevic.com · 07/05/2026

If someone told me 10 years ago that I’d be giving a talk at @scipyconf.bsky.social, I would’ve called them crazy. I’m incredibly honored that the SciPy organizers think derivkit is worthy of a talk! Thank you, SciPy team 🥹🥹🥹🥹

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Niko @nikosarcevic.com · 21/04/2026

Fresh on @arxiv 🥳🥳🥳🥳 Blinding in cosmology is especially challenging: unlike particle physics, our signal is statistical, subtle, and extracted through a long inference chain. Excited to share the official LSST DESC tool for blind analyses: arxiv.org/abs/2604.18111

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Niko @nikosarcevic.com · 14/03/2026

Happy bday, arXiv! You are the best! Funny coincidence is that I chose to wear one of my arXiv shirts (which are top quality btw! Hoodies as well, highly recommend)

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Niko @nikosarcevic.com · 11/03/2026

I am a science machine 💪💪💪💪 4th paper fresh on the @arxiv.bsky.social this year 🥳🥳🥳 arxiv.org/pdf/2603.09973

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Niko @nikosarcevic.com · 03/03/2026

Starting the day shearing dead weeds in the forest and cutting through mountain mint — that sharp minty scent mixed with damp, rotting leaves — pure peace for the soul 🌿 And catching up with the wonderful folks over at @DukeLemurCenter is just 👌chefs kiss

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Niko @nikosarcevic.com · 26/02/2026

Two more works on the @arxiv 🥳🥳🥳 arxiv.org/abs/2602.21863 arxiv.org/abs/2602.21280

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Niko @nikosarcevic.com · 12/02/2026

I don’t know that!!! I do indeed smile a lot. Here’s me smiling with one helluva guy (photo taken few years ago)

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Niko @nikosarcevic.com · 10/02/2026

Aaaaaand it’s officially on @arxiv.bsky.social 🥳🥳 arxiv.org/abs/2602.08078 Wanna do Fisher, XY Fisher or DALI with a chosen derivative method backend in a simple sleek Python way? Look no further, my friend. We got you! Simple examples here docs.derivkit.org/main/example...

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Niko @nikosarcevic.com · 13/01/2026

Ok, aside that this was ten years ago (wthhhhell 😱) and I now feel ancient, it is actually nice to be reminded of good times during masters in Göttingen: Thorsten was my lecturer in cosmology and string theory courses and was super encouraging. Made me fall in love with cosmo 🤩

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Niko @nikosarcevic.com · 04/01/2026

Actually — the first burek in the states since I moved 😱 Found the ingredients at Whole Foods Also a selfie just because

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Niko @nikosarcevic.com · 01/01/2026

X marks the spot Happy first day of 2026! It’s cold here but nothing beats the Carolina blue 😍

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Niko @nikosarcevic.com · 19/12/2025

There probably are a few things better than talking to Alan Heavens about a potential idea then heading to the woods and mulching sumac trees (for the lemurs!) with your best guy on a warm December morning but I can’t think of any right now. I just love the 🇺🇸 🍂🛻🪏

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Niko @nikosarcevic.com · 02/12/2025

If you are around these parts, come and join us for a pint and a nice story about the Universe

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Niko @nikosarcevic.com · 24/11/2025

I can say with full confidence I’m the happiest person on this planet right now. Seeing the Roman Space Telescope being assembled — and knowing it’ll be in orbit next year — just makes it unreal.

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Niko @nikosarcevic.com · 22/11/2025

It’s a wrap! @nasaromantelescope.bsky.social NASA Roman HLIS Cosmology Project Infrastructure Team face to face meeting Thank you to Bhuv, Mike and the rest of UPenn folk for hosting us 🙏

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Niko @nikosarcevic.com · 10/11/2025

The only acceptable way to start the Leiden research visit is to have coffee with Dr Evil Villain (in our secret Narnia caffe) @ivovanvulpen.bsky.social (For those of you who don’t know, Ivo is responsible for the amazing wall formulas in Leiden; see photo 2 where Matthijs and I are kissing)

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Niko @nikosarcevic.com · 09/11/2025

Happy to be back in one of the loveliest places on this planet 🇳🇱🚲🌷🧀🌊

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Niko @nikosarcevic.com · 04/11/2025

One of the perks of academia — you have awesome colleagues all over the world so dinners in great company are always guaranteed

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Niko @nikosarcevic.com · 04/11/2025

Lovely day at the Paris observatory with old Twitter friends! All Paris talks delivered!

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Niko @nikosarcevic.com · 02/11/2025

When two stats nerds from way back randomly find themselves in Paris at the same time — talk about serendipity!!!! @knut.dundasmora.no 😍 It was beyond lovely to spend an afternoon in Paris with you

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Niko @nikosarcevic.com · 31/10/2025

Happy Halloween from me and my buggy code

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Niko @nikosarcevic.com · 29/10/2025

A little treat for myself: two adorable mini Kurt Geiger bags ✨ My first one was a Heathrow purchase two years ago — guess it was the start of a collection 👀

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Niko @nikosarcevic.com · 22/10/2025

🤬 why does everything pass locally on macOS but CI (Linux) decides my cubic’s 3rd derivative is 24.0000001999 instead of 24?! Apparently OpenBLAS and Apple’s Accelerate don’t round the same way 🤦‍♀️ IT IS UNIXXXXXXXX Numerical analysis: 1, sanity: 0 (Managed to fix, still angry)

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Niko @nikosarcevic.com · 21/10/2025

6 °C in Durham this morning 🌿 Early woods + chilly air = time to grab a shovel! Cleared out a bunch of sweet gum trees — perfect, since we’re expanding the food gardens AND the lemurs get a feast 🍃 A wonderful morning at the Duke Lemur Center with my garden crew 🦋

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Niko @nikosarcevic.com · 13/10/2025

spent an embarrassingly long time making these plots (wanted to procrastinate) holy pagan gods, @matplotlib has been on fireeeee 🔥 the past few days i think they’re correct … but for now i’m just gonna enjoy looking at them because they pretty 🤩 thanks to @matthijs.vanderwild.com for helping 😍

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Niko @nikosarcevic.com · 06/10/2025

The sky is particularly beautiful here in NC So is the Moon 🌕🤩

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Niko @nikosarcevic.com · 30/09/2025

New paper out, baby We build & validate six intrinsic alignment models infused directly into weak lensing simulations, enabling robust inference beyond 2pt stats. I led the full validation with MCMC chains—took years to get here! Excited this is FINALLY out 🎉 arxiv.org/abs/2509.25166

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Niko @nikosarcevic.com · 27/09/2025

I am so good at multitasking between bash WhatsApp and slack

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Niko @nikosarcevic.com · 27/09/2025

Oh you bought another book? Did you finish the life sentence yet? Yes. No. Also, blame it on @telescoper.bsky.social for posting about this book yesterday.

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Niko @nikosarcevic.com · 26/09/2025

Recently submitted a second round of comments, thought I might be nitpicky — then I see this 🤣🤣🤣 The universe is telling me something here (I am never ever rude tho)

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Niko @nikosarcevic.com · 25/09/2025

I pay for all the subscriptions both in the UK and the US Matthijs texted me he ordered some household essentials on Amazon this morning The household essentials: 🤣🤣🤣🤣🤣🤣😅😅😅

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Niko @nikosarcevic.com · 23/09/2025

Heavy lifting at the Duke Lemur Center this morning! 😌

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Niko @nikosarcevic.com · 23/09/2025

Here are more photos (Šarčević et al., 🤩) taken during the LSST DESC and echoIA workshops I had the pleasure of organizing here at @DukePhysics

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Niko @nikosarcevic.com · 18/09/2025

Taken by me at exactly 5:37 am in Durham NC looking east No clue what it is but deffo was interesting

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Niko @nikosarcevic.com · 02/09/2025

First morning volunteering at the Duke Lemur Center 🌱 Did some gardening, picked veggies for the lemurs, met cool people, weeded a bunch. It was fun — and we found a bunch of these small guys 🐍 Bliss 😌😌😌

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Niko @nikosarcevic.com · 26/08/2025

Just unpacked a stunning shipment from @pennmuseum.bsky.social : • Canopic jar set (made in Egypt, super heavy!) • Mayan carved bone • Jaina figure Huge thanks to the gift shop staff for the careful packing—it all arrived in perfect condition. I love this so much! 🖤

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Niko @nikosarcevic.com · 23/08/2025

A bday stroll thru the ever amazing Sarah Duke Gardens 😌

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Niko @nikosarcevic.com · 11/08/2025

One of the main reasons (apart from being an absolute amazing center of history/art/science/culture) why I think Philly is amazing: it is just so walkable 😍

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Niko @nikosarcevic.com · 10/08/2025

In front of the city hall 5/ G’night yall

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