Niko
@nikosarcevic.com
human person (she)
| cosmologist at Duke University
| member of @LSSTDESC @Roman
| did physics @XENONexperiment
| loves plots, coats, and The Wire
| opinions mine
| cosmologist at Duke University
| member of @LSSTDESC @Roman
| did physics @XENONexperiment
| loves plots, coats, and The Wire
| opinions mine
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)
(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)
November 10, 2025 at 10:51 AM
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)
(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)
Happy to be back in one of the loveliest places on this planet
🇳🇱🚲🌷🧀🌊
🇳🇱🚲🌷🧀🌊
November 9, 2025 at 2:29 PM
Happy to be back in one of the loveliest places on this planet
🇳🇱🚲🌷🧀🌊
🇳🇱🚲🌷🧀🌊
One of the perks of academia — you have awesome colleagues all over the world so dinners in great company are always guaranteed
November 4, 2025 at 10:06 PM
One of the perks of academia — you have awesome colleagues all over the world so dinners in great company are always guaranteed
Lovely day at the Paris observatory with old Twitter friends!
All Paris talks delivered!
All Paris talks delivered!
November 4, 2025 at 2:43 PM
Lovely day at the Paris observatory with old Twitter friends!
All Paris talks delivered!
All Paris talks delivered!
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
@knut.dundasmora.no 😍
It was beyond lovely to spend an afternoon in Paris with you
November 2, 2025 at 4:24 PM
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
@knut.dundasmora.no 😍
It was beyond lovely to spend an afternoon in Paris with you
Happy Halloween from me and my buggy code
October 31, 2025 at 7:49 PM
Happy Halloween from me and my buggy code
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 👀
My first one was a Heathrow purchase two years ago — guess it was the start of a collection 👀
October 29, 2025 at 4:41 PM
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 👀
My first one was a Heathrow purchase two years ago — guess it was the start of a collection 👀
🤬 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)
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)
October 22, 2025 at 4:24 AM
🤬 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)
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)
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 🦋
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 🦋
October 21, 2025 at 2:47 PM
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 🦋
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 🦋
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 😍
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 😍
October 13, 2025 at 4:53 AM
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 😍
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 😍
The sky is particularly beautiful here in NC
So is the Moon 🌕🤩
So is the Moon 🌕🤩
October 5, 2025 at 11:05 PM
The sky is particularly beautiful here in NC
So is the Moon 🌕🤩
So is the Moon 🌕🤩
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
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
September 30, 2025 at 5:45 AM
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
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
I am so good at multitasking between bash WhatsApp and slack
September 26, 2025 at 11:45 PM
I am so good at multitasking between bash WhatsApp and slack
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.
Yes. No.
Also, blame it on @telescoper.bsky.social for posting about this book yesterday.
September 26, 2025 at 11:26 PM
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.
Yes. No.
Also, blame it on @telescoper.bsky.social for posting about this book yesterday.
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)
The universe is telling me something here (I am never ever rude tho)
September 26, 2025 at 10:18 PM
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)
The universe is telling me something here (I am never ever rude tho)
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:
🤣🤣🤣🤣🤣🤣😅😅😅
Matthijs texted me he ordered some household essentials on Amazon this morning
The household essentials:
🤣🤣🤣🤣🤣🤣😅😅😅
September 25, 2025 at 11:11 AM
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:
🤣🤣🤣🤣🤣🤣😅😅😅
Matthijs texted me he ordered some household essentials on Amazon this morning
The household essentials:
🤣🤣🤣🤣🤣🤣😅😅😅
Heavy lifting at the Duke Lemur Center this morning!
😌
😌
September 23, 2025 at 6:29 PM
Heavy lifting at the Duke Lemur Center this morning!
😌
😌
Here are more photos (Šarčević et al., 🤩) taken during the LSST DESC and echoIA workshops I had the pleasure of organizing here at @DukePhysics
September 23, 2025 at 2:14 AM
Here are more photos (Šarčević et al., 🤩) taken during the LSST DESC and echoIA workshops I had the pleasure of organizing here at @DukePhysics
Taken by me at exactly 5:37 am in Durham NC looking east
No clue what it is but deffo was interesting
No clue what it is but deffo was interesting
September 18, 2025 at 10:03 AM
Taken by me at exactly 5:37 am in Durham NC looking east
No clue what it is but deffo was interesting
No clue what it is but deffo was interesting
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 😌😌😌
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 😌😌😌
September 2, 2025 at 2:43 PM
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 😌😌😌
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 😌😌😌
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! 🖤
• 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! 🖤
August 26, 2025 at 7:50 PM
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! 🖤
• 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! 🖤
A bday stroll thru the ever amazing Sarah Duke Gardens 😌
August 23, 2025 at 10:44 PM
A bday stroll thru the ever amazing Sarah Duke Gardens 😌
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 😍
August 11, 2025 at 4:14 AM
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 😍
In front of the city hall
5/
G’night yall
5/
G’night yall
August 10, 2025 at 3:36 AM
In front of the city hall
5/
G’night yall
5/
G’night yall