oce

joined 2 years ago
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[–] oce@jlai.lu 4 points 2 weeks ago* (last edited 2 weeks ago)

I was surprised so I did the computation just to resolve the disk of Betelgeuse at 550 nm, and I found a telescope of 2.8 m, that's definitely already doable. We already have 8 m in one piece and 10 m segmented, JWST is 6.5 m segmented. The ELT is planned to be 39 m for 2028. So this star is closer and bigger than I thought.

And these are the images we have from one of the top imaging instrument SPHERE on the VLT in 2019. It's precise enough to show the change of shape due to its variable star type.

[–] oce@jlai.lu 7 points 2 weeks ago (2 children)

It would be the size of the telescope's diffraction artifacts probably. Meaning the shape you see on the picture is not related to the size of the star but only to the physical limits of the optical instrument. This diffraction pattern is proportional to the color your looking at and inversely proportional to the size of the telescope primary mirror. The bigger the telescope primary mirror, the smaller the diffraction pattern and the more chance you have that this artifact will not completely hide the object you are looking at. I didn't do the math, but I guess to image the actual disk of Betelgeuse, the size of the telescope you need is probably still science fiction, even with interferometry.

[–] oce@jlai.lu 4 points 2 weeks ago

C'est de la psychologie inversée.
smart animated

[–] oce@jlai.lu 8 points 2 weeks ago (2 children)

oui pcq c’est snoopy

[–] oce@jlai.lu 41 points 2 weeks ago

Is that worth losing fries?

[–] oce@jlai.lu 3 points 2 weeks ago* (last edited 2 weeks ago) (3 children)

La Légion d'honneur récompense tout un tas de personnes qui ne sont exposées ni politiquement ni médiatiquement. Par exemple, beaucoup de fonctionnaires en poste de direction la reçoivent "simplement" pour années de services. C'est environ 2000 par an pour un maximum de 125 000 membres vivants.

[–] oce@jlai.lu 5 points 2 weeks ago (1 children)

Je comprends l'argument que les USA avait peut-être déjà des simulations performantes. Je suppose qu'ils ne partageaient pas forcément les informations pour préserver leur avance technologique et que la France tenait à son indépendance stratégique.

[–] oce@jlai.lu 1 points 2 weeks ago (1 children)

Do you realize you are also spreading “right-wing ideas,” such as “we should not mock them, it would be very mean”?

Do they? You're the first one I read mentioning that.

I'm worried that by using their tactics you contribute to popularizing their ways.

[–] oce@jlai.lu 5 points 2 weeks ago (3 children)

Non, on savait déjà faire des simulations précises de l’efficacité de nos armes nucléaires.

Je ne trouve pas où cela est confirmé dans le rapport. Ils disent que le programme de simulation a été lancé en 1995, puis tous les programmes mentionnés sont post 2005.
Ayant étudié la physique et travaillant dans l'informatique, j'ai des doutes que des simulations informatiques dans les années 90 aient pu produire beaucoup de résultats pertinents.

En outre, en science en général, on essaye toujours de comparer le résultat du modèle informatique qui est inévitablement une simplification de la théorie, avec des observations de la réalité pour s'assurer que la théorie ou le modèle ne créé pas des résultats imaginaires.
Donc d'un point de vue purement recherche physique, ça semble raisonnable de nécessiter des expériences réelles pour encadrer les simulations informatiques.
En considérant l'impact environnemental, je ne dis pas que ça vallait le coup.

C'est d'ailleurs une des raisons principales du développement du Laser Mégajoule par le CEA en ce moment, c'est une expérience qui permet de continuer à observer la physique de haute énergie sans faire exploser de bombe nucléaire. En espérant que ça aura des retomber scientifiques sur d'autres domaines utiles à la société, comme la recherche en physique nucléaire en a déjà beaucoup.

[–] oce@jlai.lu 1 points 3 weeks ago (3 children)

Do you realize you are using similar arguments as the far right / masculinist by mentioning nerds, losers, mockery, charisma, soft boys, soy drinkers, display of power?

I said before I'm considering those who may still listen and the next generation. I know you can't change the current maga-like with public education.

[–] oce@jlai.lu -1 points 3 weeks ago (6 children)

You have to compete with the content they produce regardless.

No, you can educate people from the start so they are able to weed out information by themselves.
Isn't it what you do? You are educated so you are able to detect the far right bullshit.
Or are you really watching a bigger amount of content that ridicule this view in order to counter its effect?

[–] oce@jlai.lu 7 points 3 weeks ago (1 children)

As you can see, I said "reputation". I hate how little they innovate while still selling at premium, but similar to Disney, it is enough for the casual mass.

18
Gum arabic - Wikipedia (en.m.wikipedia.org)
submitted 1 month ago* (last edited 1 month ago) by oce@jlai.lu to c/wikipedia@lemmy.world
 

Gum arabic (gum acacia, gum sudani, Senegal gum and by other names[a]) (Arabic: صمغ عربي) is a tree gum exuded by two species of Acacia sensu lato, Senegalia senegal[2] and Vachellia seyal. The gum is harvested commercially from wild trees, mostly in Sudan (about 70% of the global supply) and throughout the Sahel, from Senegal to Somalia.

Gum arabic is a complex mixture of glycoproteins and polysaccharides, predominantly polymers of arabinose and galactose. It is soluble in water, edible, and used primarily in the food industry and soft drink industry as a stabilizer, with E number E414 (I414 in the US). Gum arabic is a key ingredient in traditional lithography and is used in printing, paints, glues, cosmetics, and various industrial applications, including viscosity control in inks and in textile industries, though less expensive materials compete with it for many of these roles.


Gum arabic exuding from Acacia nilotica. Ashwin Baindur (User:AshLin) • CC BY-SA 4.0

 
 
 
 
 

This third day sucked.

My legs and feet began to feel the strain of walking over 50 km in just a few days for the first time in my life, especially without proper training.

Additionally, it was rainy and much colder than I had anticipated for this time of year. I found myself shivering and questioning what was happening to me, was it simply exhaustion? It wasn't until later that day, after I reached my place for the night, that I learned it had been just 3°C that morning. I had been walking in only shorts, a light sweater, and a rain cape.

Nonetheless, the path today was nice, with mostly woods and fields.

Finding some shelter from the rain and cold in a beautiful church on the way.

Once again, I couldn't find any cheap pilgrim stay, so I ended up staying at an out of budget bed and breakfast. At least, it was a charming old farmhouse.

I am part of this rare breed of cooking pilgrims. The hosts didn’t offer dinner; after all, it was a B&B, not a B&D&B! However, they did provide a ride to the grocery store, so I took advantage of that and prepared myself a hearty meal. In my book, taking transportation is ok as long as you restart walking from where you ended. My hosts were quite amused by the fact that I did cook myself a full, balanced meal, instead of just eating pasta and cheese.

 
249
submitted 2 months ago* (last edited 1 month ago) by oce@jlai.lu to c/pics@lemmy.world
 

Photography from a bridge with a red metal fence, looking over the Merguro river, lined with white flowering cherry trees on both sides.

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