🎁 #Concours 🎁
Découvrez nos offres durant les French Days sur Cdiscount !
🇫🇷 https://t.co/sA6zcAJdlV
🤑 Et tentez de remporter 2x500€ en bons d'achat :
✔️ RT + FOLLOW @Cdiscount
✔️✔️ TWEET avec #CDISCOUNTFRENCHDAYS
👇
Google estime que dès 2029, un ordinateur quantique suffisamment puissant pourrait casser les systèmes de chiffrement classiques qui protègent l'essentiel de nos communications. C'est ce qu'on appelle le "Q Day".
Face à cette menace, il existe un système de chiffrement qui ne repose pas sur la difficulté d'un calcul mathématique, mais sur les lois de la physique : si quelqu'un tente d'intercepter la communication, le simple fait d'observer les photons trahit immédiatement sa présence. Ses inventeurs, Charles Bennett et Gilles Brassard, viennent de décrocher le prix Turing 2025, le "Nobel de l'informatique" (et son million de dollars). https://t.co/sjAcNmgt0r
I keep seeing a misconception that transmission lines are made out of copper.
For the vast majority of lines (especially overhead), that's not the case.
Most power lines are made from a steel core wrapped with aluminum conductors.
(that's why power lines look silvery and not coppery)
Steel provides the strength, and aluminum provides the conductivity.
(they both provide some of each but that's primarily how it works)
But isn't copper more conductive than aluminum?
For the same cross sectional area, aluminum is only about 60% as conductive as copper, but it's also only 30% as dense as copper.
For the same mass of metal, aluminum is about twice as conductive as copper.
Copper is better when you're space constrained (like in an electric motor), but aluminum is better when you're weight constrained.
Aluminum isn't just a cost saving measure (although it does cost 1/4th as much per kg). For a lot of applications, aluminum is actually better than copper.
J'ai annoncé que j'étais allé à Dubaï pour parler de désinformation sur base d'un Tweet, que j'ai croisé la mère d'Elon Musk etc? Et bien... Presque 😃👇