John F Wu

@jwuphysics

Tenure-track astronomer working on galaxies, machine learning, and AI for scientific discovery. Opinions my own. He/him. Website:

667 Folgt3.933 Follower1.347 Posts

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Ist das dein Profil?Übernimm es — dann gehört dir jwuphysics.dirty.social.Profil übernehmen

John F Wu@jwuphysics· 1d

Eclipse. Ten years of marriage.

A view of the sunset total eclipse over water, off the coast of Mallorca.

John F Wu@jwuphysics· 16d

Having grown up in Sulphur, Louisiana, I can verify that this wikipedia picture of "downtown" is a representative view of Sulphur

A screenshot of Sulphur's wikipedia page. The headline picture is a rainy small town intersection with a few street signs and like two low rise buildings. There is one car on the road and two parked.

The rest of the page can be read at the link but it just says:

Sulphur, Louisiana
City in Louisiana, United States

Not to be confused with Port Sulphur, Louisiana.
Sulphur is a city in Calcasieu Parish, Louisiana, United States. The population was 21,809 in 2020. Sulphur is part of the Lake Charles metropolitan statistical area.

Quick facts Country, State ...
History
Sulphur is named for the sulfur mines that were
[...]

John F Wu@jwuphysics· 28d

Gonna J-lens the crap out of that first and only token

John F Wu@jwuphysics· 29d

Okay fine now it's kind of uncomfortable in Baltimore (46C heat index)

Wunderground website showing the current temperature in Baltimore as 98F and with heat index of 115F. The map nearby shows stations reporting between ~97-103F degrees in Baltimore.

John F Wu@jwuphysics· Jul 11

I don't think I've ever seen a soccer throw-in bat flip

Basallo bat flipping like a soccer throw-in toward his own dugout after his go-ahead home run in the bottom of the 8th

John F Wu@jwuphysics· Jul 10

Winds are starting to pick up now and the eye is showing up on radar. Bavi is a ridiculously large storm!

John F Wu@jwuphysics· Jul 10

Here we go!

Radar from Taiwan showing heavy rain over northern Taiwan, and multiple rain bands offshore from Typhoon Bavi.

John F Wu@jwuphysics· Jul 8

I need to find @depthsofwikipedia.bsky.social while holding this in my hand (just eaten in Ningxia night market)

Me holding a night market street food classic, "大腸包小腸" aka "small sausage in large sausage"

John F Wu@jwuphysics· Jul 1

Loeb's team will report to a new White House panel focused on UFOs, now often referred to as unidentified anomalous phenomena, or UAP.

"lt's like a detective story," Loeb said in an interview. "It's a lot of fun, as long as you don't pay too much attention to the ~~critics."~~ facts

Note: "critics" is crudely crossed out and replaced with "facts"

John F Wu@jwuphysics· Jun 29

Views of National Taiwan University and the city of Taipei, from my office building in the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA).

A view of the National Taiwan University from a high observation deck, overseeing the famous Drunken Moon Lake and a few other buildings, with mountains on the back.

John F Wu@jwuphysics· Jun 27

Can confirm, Baltimore was buzzing today

Upward point photo shows the flags up on a tall ship and seven jets flying in formation with red white and blue colored trails.

John F Wu@jwuphysics· Jun 27

Not like Baltimore is much better...

John F Wu@jwuphysics· Jun 27

So excited to give a colloquium in Taiwan... hm let's see what to pack based on the weather

John F Wu@jwuphysics· Jun 26

How you know you married the right one

John F Wu@jwuphysics· Jun 20

Flattering, I guess

JOHN F. WU

ASTRONOMER AND DATA SCIENTIST

> 237 STRENGTH TOP 25% <

CLAUDE OPUS 4.8 SAYS ASTRONOMER AT THE SPACE TELESCOPE SCIENCE INSTITUTE FOCUSED ON GALAXY EVOLUTION, MACHINE LEARNING, AND APPLYING AI/DEEP LEARNING TO ASTROPHYSICAL DATA.

With a bar chart showing (presumably how much each model knows about "John F. Wu" from 0-100%):
GPT-5.5 0%
GPT-5.4 MINI 0%
CLAUDE OPUS 4.8 ~60%
CLAUDE HAIKU 4.5 0%
GROK 4.20 ~75%
GEMIΝΙ 3.1 LITΕ 0%
KIMI K2 0905 ~85%
DEEPSEEK V4 ~95%
LLAMA 3.3 70B 0%
LLAMA 3.2 1B 0%
GLM 4.7 FLASH 0%
MISTRAL 3.2 24B 0%
QWEN3 8B 0%

John F Wu@jwuphysics· Jun 17

Pinging @depthsofwikipedia.bsky.social Mostly just because of "Liking for gravy" with an arrow, annotated 20th C., pointing to the UK, and "A novelty Pizza topping" for some reason off the coast of Oman?

A map with block diagram arrows pointing around how Tikka Masala spread.

Caption: Evolution of chicken tikka masala as a multicultural British dish.[41][4] Chicken tikka was created in Mughal India using Persian marinading of meat in yoghurt and Central Asian tandoor roasting with Indian spices.[42] In 20th century Britain, a sauce was added to meet the British liking for gravy with meat.[12] The dish has evolved further to a taco filling in the US,[36] and to a pizza topping in India.[39] Tacos originated from Mexico.[43] Pizzas originated from Italy.[44]

From: https://en.wikipedia.org/wiki/Chicken_tikka_masala#/media/File:Evolution_of_Chicken_Tikka_Masala.svg

John F Wu@jwuphysics· Jun 6

Last two panels of the SpongeBob "Stop it Patrick you're scaring him" meme:

Patrick mouthing "oooh" next to an exasperated Squidward with the text: "BALTIMORE IS A BEAUTIFUL CITY"

SpongeBob worried with hands in the air: "STOP IT PATRICK YOU'RE SCARING HIM"

John F Wu@jwuphysics· Jun 6

Gorgeous day for Charles Street Promenade!

A couple dozen vendors and hundreds of pedestrians walking up and down N Charles St in Baltimore.

John F Wu@jwuphysics· Jun 2

This is the worst looking photo they could snap of Mamdani 😭

New York Post full front page showing Mamdani smiling from a bicycle, with giant text "CYCLE OF HATE" and "Zo snubs Israel parade, goes on bike ride instead"

John F Wu@jwuphysics· May 28

About as beautiful weather as it gets... 25C at Camden Yards

John F Wu@jwuphysics· May 28

Gemini 3.5 flash is a bit better, although I'm not sure if that's simply scaffolding

There are 3 "r"s in "stwawbewwy".
If we break it down letter by letter:
s - t - w - a - w - b - e - w - w - y ... wait, looking closely at how you spelled it:
s t w a w b e w w y
There are actually 0 "r"s in your exact spelling ("stwawbewwy") because they've all been replaced with "w"s!
(If you meant the standard spelling, "strawberry", then there are 3 "r"s: strawberry).

John F Wu@jwuphysics· May 28

How many rs are there in stwawbewwy (Google search)

Response:

Did you mean: How many rs are there in strawberry
AI Overview
There are 3 "r"s in stwawbewwy (stwawbewwy).
If you spell it "strawberry," there are also 3 "r"s: strawberry!

John F Wu@jwuphysics· May 14

Sounds like commuting Baltimore all right

Image of adults and kids biking, partly in a protected lane, and partly into the car lane, as they navigate around a parked car. Below it are a caption and some text from the excerpt.

Caption of image: Adam Conway, right, directs the bike bus students around a truck unloading in the bike lane on the way to Roland Park Elementary/Middle School. (Jerry Jackson/The Banner)

Text excerpt from article: As the kids approached a red light just blocks from school, a silver Volkswagen SUV with a shiny Virginia license plate was parked and blocking the bike lane. Parents pedaled into the car traffic lane and slowed down so the kids could go around; as they did, several of the kids loudly booed the car. The idling driver’s eyes remained glued to her phone.

John F Wu@jwuphysics· May 3

When life gives you 韭菜, obviously you have to make 韭菜肉包

John F Wu@jwuphysics· Apr 16

So cool that Annual Reviews sent me a physical volume of ARA&A 63! A great memento from when I served as a guest reviewer.

A picture of me holding the physical copy of the Annual Reviews of Astronomy and Astrophysics, Volume 63, 2025.

John F Wu@jwuphysics· Apr 10

My 20 month old son looking like the old Indian man meme

John F Wu@jwuphysics· Apr 8

The two main findings about AI in for learning: AI impairs performance and it reduces persistence.

To preview our findings, we find that AI assistance impairs independent performance and reduces
persistence. Although AI assistance improves performance during assisted sessions, people’s perfor-
mance drops sharply once AI is removed. More strikingly, relative to the controls, participants in the AI
condition also persist less with tasks and give up more frequently. This pattern is robust and replicates
across domains. These effects emerge after a brief 10–15 minute session, raising the question of what
prolonged AI use does to human capability over time.
Our results are notable on two fronts. First, while concern about AI-induced deskilling has grown,
prior evidence has been largely correlational (Budzy ´n et al., 2025; Gerlich, 2025) or limited to small
samples (Kosmyna et al., 2025; Shen & Tamkin, 2026). Here, through a series of randomized controlled
trials on human-AI interactions, we provide the first large-scale causal evidence of this effect. Second,
we demonstrate how AI can result in loss of motivation and persistence. A rich body of literature
in cognitive science and education has shown that the capacity to regulate effort and persist through
difficulty is foundational to effective learning, and is among the strongest predictors of long-term
academic achievement, workforce adaptability, and resilience (Metcalfe & Mischel, 1999; Duckworth
et al., 2007; Maddux, 2009; Metcalfe, 2009; Andersson & Bergman, 2011; Bjork et al., 2011; Kapur, 2014;
Guiso et al., 2016; Mooradian et al., 2016). Our results suggest that AI assistance erodes precisely these
capacities. People do not merely become worse at tasks, but they also stop trying. If such effects
accumulate over months and years of AI use, we may end up creating a generation of learners who have
lost the disposition to struggle productively without technological support.

John F Wu@jwuphysics· Apr 1

FWIW I didn't read this paper, just skimmed, so I don't know how much of the findings hinge on the *photometric* catalogs. The DESI targeting catalogs are much more conservative and don't seem to be as susceptible to shreds. The photometric catalogs on the other hand...

Example galaxy and DESI DR9 photometric catalog that "shreds" the foreground galaxy into ~10 sources.

John F Wu@jwuphysics· Mar 30

The joy of being a STScI astronomer 🤩 Spotted at BWI airport

A scene at the BWI airport showing a zoom in of the Carina nebula

John F Wu@jwuphysics· Mar 22

Decided to catalog the amazing deals at Lidl today