Raytracing in Rust!

I have started a project that requires the use of a raytracer. Basically, I hope to make a library for rendering optical paths using raytracing and simulate the result that one would get by looking through the optical system. Hopefully, I would like to be able to write somewhere that I will have a couple of lenses here and there, give the parameters such as the refractive index and curvatures and diameters and get the resulting image on a focal plane. To do this, I need to start small, and I thought that the way to start small was to …

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My Five-Month Journey with AI: Expectations vs Reality

So, 5 months ago, I have written a post about Artificial Intelligence and General Artificial Intelligence. You can see the tone from my first post was very optimistic, a little too much maybe, with the hope that things would accelerate soon. I have been using AI a lot recently and I want to report on my understanding of what AI can and can’t do and how to use it as effectively as possible. Small disclaimer: I have mostly used ChatGPT, and a little of the other Large Language Models (LLMs) like Bard and Llama, so I will mostly talk about …

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How do big telescopes look through the atmosphere – Adaptative Optics 101

Continuing my series of post covering my talk from last Christmas about the use of lasers in space and astronomy. The topic today is adaptative optics. I’ll explain the reason why we need it, and how it works in simple terms. Enjoy. No surprise: telescopes are the main tool of astronomers. Since Newton, we have built countless telescopes of various sizes and shapes. And lately, we even send them to space. We have Hubble, the JSWT for the more famous, and a lot of other space telescopes less known. But why sending them to space? After all, space is difficult. …

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What is the difference between a regular lamp and a laser? A brief history of Optics and Lasers

So this post and a bunch after this one are from a talk I presented at the end December on the topic of lasers in space and astronomy. The target the audience was members from astronomy groups in the region with some knowledge of optics but not necessarily lasers and the curious people that might be interested but have a physics background from high school. I tried to make it interesting for a wide audience, and I would say that it is accessible to some degree to someone in high school, maybe earlier? Anyway, the goal was to be entertaining, …

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Rayons crépusculaires depuis Neuchâtel

L'ombre des géants

Prise le 4 janvier 2023, avec mon Fujifilm XT4, XF50-140mm F2.8 R LM OIS WR, à ISO 160, f2/8, 80mm et 1/250s d'exposition.

C'était une belle matinée froide ce jour là, avec deux couches de nuages, une à la surface du lac de Neuchâtel, et une autre à environ 3000m. Juste assez pour toucher la pointe de certains sommets des Préalpes. Le soleil se levait et commençait à projeter des ombres intéressantes le long du chemin. C'est un phénomène que l'on appelle communément les rayons crépusculaires.

Bien que les ombres soient en fait parfaitement parallèles les unes aux autres, la perspective donne l'impression que les ombres des pics convergent vers le soleil.

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L'intelligence artificielle et le monde de demain

Comme beaucoup d'autres, j'ai suivi ce qui est le plus grand changement de paradigme de ces cent dernières années. À mon avis, c'est la véritable prochaine grande étape de l'histoire de l'humanité qui est en train d'être franchie en ce moment même, comme certains semblent s'en rendre compte. Au début du XXe siècle, l'invention du moteur à combustion a tout changé. De la façon de se déplacer, à la façon de générer de l’électricité. Fondamentalement, l'intelligence artificielle est là pour faire la même chose, avec des conséquences difficilement prévisibles.

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My simple genetic algorithm in Python for polynomial curve fitting

Take the shortest route, the one that nature planned Marcus Aurelius, Meditations Genetic algorithms are really interesting in my opinion. Not the most efficient, but rather beautiful in the way they work. I especially like them because of the similarities that they share with life. Genetic algorithms are special kind of algorithms that work by modelling how natural selection works in the real world. I shouldn’t need to explain how evolution works, but for the sake of it, here I go. We have several individuals in a population, given their environment, some of the individual are better suited and reproduce, …

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Diffraction patterns in astronomical imaging

The first image from the James Webb Space Telescope (JWST) was uncover a few days ago [1]. This is truely an incredible image, showing the galactic cluster SMACS 0723, which is slowly becoming the de-facto target for newly deployed space telescopes as it was imaged by Hubble, Planck and Chandra before JWST. This image in particular took the JWST 12.5 hours of exposure to be able to see these objects as they are so dim in the sky. The best way to see how much of an achievement this is, is to compare it to the previous picture, taken by …

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Digital photonics and laser lightning rods from AKL22

I was at AKL 22 a couple of weeks ago: the international laser technology congress at Aachen, Germany. I was present for the interesting technology conference and the live presentations at Fraunhofer ILT. I have to say that after 2 years of Covid and only being able to assist to virtual conferences if available was a breath of fresh air. Virtual events are nice and you can still learn a few things, but physical events are something else. You are invested in what you hear and there is less distraction than in the office. The best part is that you …

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Quelques photos de cet hiver

Le temps passe et nous sommes déjà au mois de mai. Je n'ai pas eu le temps pendant ces derniers mois pour poster ces quelques photos... Mieux vaut tard que jamais. Photos prisent avec mon XT-4 et un objectif Fujinon XF 50-140 mm f/2.8.

Le mont Blanc et les Alpes vue depuis Neuchatel pendant un coucher de soleil
Après la chute de neige
Beaucoup d'activité dans cet arbre pour un jour d'hiver...

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