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« Moins de dépenses plutôt que plus d’impôts » : le message clair de l’OCDE à la Belgique 21news.be/moins-de-depenses-…

Overheidsuitgaven België in % BBP jaar 2000: 42,6% jaar 2026: 52,3% verschil : 9,7% van het bbp méér uitgaven! Het probleem in België zit aan de uitgavenkant. Niet bij de inkomsten.

BOOOM 🚨 Elon Musk just said it's much easier to cool AI chips in space than on Earth, and the physics actually backs him up 🔥 To most people that sounds backwards. Space is a vacuum, and a vacuum is the best insulator there is. One viral post even used it to question whether Elon is a real engineer. The critics got the first step right. They just stopped thinking one step too early. 🧊 THE THERMOS SECRET To see where they slipped, start with how a chip stays cool on Earth. A fan blows air across it, or water flows past it, and the heat gets carried away. In space there's no air and no water, so nothing can carry the heat off. The critics are right about that much. But a thermos tells the rest of the story. It keeps coffee hot with a vacuum between two walls, and those walls are coated like a mirror. The mirror is there for a reason. Heat still escapes through a vacuum as infrared light, the invisible glow you feel on your face near a campfire. So space doesn't trap heat. It just closes every exit except one. A space radiator uses that last exit on purpose. It's an anti-thermos, a panel with a special coating built to glow away as much heat as possible. So the real question is how fast a panel can glow heat away. 🔥 WHY SPACE IS THE PERFECT HEAT DRAIN Everything warm glows in infrared, including you and the cup of coffee on your desk. The hotter something is, the brighter it glows, and the effect snowballs fast. Physicists call this the Stefan-Boltzmann law, which says the glow grows with temperature, counted from absolute zero, raised to the fourth power. In everyday terms, a little extra heat buys a lot of extra cooling. A panel at around 65°C (149°F), about as hot as coffee that's just cool enough to sip, sheds about twice as much heat as one at a cool 10°C (50°F). Then there's the backdrop. Deep space sits at about minus 270°C, which is what Elon means by "3 degrees above absolute zero," and it sends almost no heat back. Picture stepping outside on a freezing winter night instead of into a sauna. Out in the cold, your body heat just pours away. That's what a radiator feels in orbit, every second of every day. That one-way street is where Elon's numbers come from. 🧮 ELON'S NAPKIN MATH Start with the radiator. One square meter of aluminum panel, turned edge-on to the Sun and glowing from both sides, can dump about 1,300 watts. That's nearly the output of a household space heater from a panel the size of a small table. Now the solar panels. Sunlight in orbit delivers about 1,361 watts per square meter, and a solar panel turns only about 250 watts of that into electricity. Here's the brilliant part. Every bit of electricity the chips use ends up as heat, because energy never disappears. It just changes form. The solar panels deal with their own leftover sunlight by glowing it away themselves. That means the radiator only has to handle the electricity that actually reaches the chips. Each square meter of radiator can get rid of about five times what each square meter of solar panel produces. So the radiator only needs to be about one fifth the size of the solar wings. The "impossible" cooling problem turns out to be the smaller part of the satellite. That's why Elon says most of its mass is solar panels. This isn't just napkin math, either. SpaceX built its first AI satellite around it. 🛰️ SPACEX'S AI SATELLITE RUNS ON THIS MATH SpaceX's first AI satellite is wider than a Boeing 747, and every square meter of it follows this math. SpaceX's June design for its AI1 satellite assumed 250 watts per square meter for the solar array and about 1,400 for double-sided radiators turned edge-on to the Sun, slightly more optimistic than the 1,300 in Elon's reply. It paired 110 square meters of liquid radiator with 120 kW of sustained power and 150 kW at peak. Multiply 110 by 1,400 and you get about 154 kW, a clean match. A kilowatt is a thousand watts, so 120 kW is roughly what a hundred American homes use on average. The satellite has since grown to a 75-meter wingspan and up to 250 kW at peak. That peak matches what a V3 Supercharger can push into a Tesla. The first launch is targeted for the fourth quarter of 2027, which is a lot sooner than "not in our lifetimes." The brains inside will be a space-optimized version of Nvidia's Vera Rubin NVL72 system. Data center chips are already running in orbit, too. Starcloud launched a satellite carrying an Nvidia H100 in late 2025 and used it to train the first AI model in space. Just as impressive is how little cooling hardware the whole thing needs. ⚙️ A COOLING SYSTEM WITH ALMOST NOTHING TO BREAK A data center on Earth is a giant building full of fans and chillers, often with cooling towers that evaporate water. In orbit, a fluid soaks up heat next to the chips, hands that heat to the aluminum panel, which glows it away, and then loops back forever. SpaceX backs this up with redundant pumping loops and built-in shielding against tiny space debris, so a few pumps do the job of a whole building of cooling equipment. Elon goes even further and says the AI satellite is simpler than a Starlink satellite, because it skips Starlink's complex antennas. The physics was never the hard part. The hard part was the cost of lifting giant panels into orbit, and that's exactly the problem Starship was built to crush. Of course, the skeptics still have a few cards to play. 💪 THE CRITICS' BEST SHOT Their favorite number comes from the International Space Station. The ISS cooling system rejects roughly 70 kW across 422 square meters of radiator, about 166 watts per square meter. That's roughly an eighth of Elon's figure. On paper, that looks bad for Elon. But temperature is a big part of that gap. The ISS keeps its cooling loops cold enough to serve astronauts, and by the fourth-power rule, cold radiators shed far less heat. AI chips run hot, which is exactly what radiators love. The ISS is a station designed in the 1990s to keep people comfortable, not a satellite designed from scratch to cool a supercomputer. Critics also point out that Earth glows in infrared too, and that radiator coatings wear down over years in orbit. Both are real, and both are design margins rather than deal breakers. SpaceX already flies and replaces thousands of Starlink satellites, so running a fleet that gets refreshed is its home turf. Then there's cost. An ABI Research model in IEEE Spectrum found that running a GPU in space for a year costs at least ten times more than on Earth. But that model assumed an Nvidia H100 rack on a spacecraft similar to Starcloud's first pilot satellite, not a purpose-built design like AI1. Even Jensen Huang, who calls today's economics poor, says they will improve over time. His own company is now building the brains of SpaceX's first AI satellite. 🚀 THE TWIST THAT CHANGES EVERYTHING Here's the part the critics missed. The fourth-power rule flips chip design on its head. Here on Earth, engineers spend fortunes keeping chips cool. In orbit, the hotter a chip can safely run, the smaller its radiator, the lighter the satellite, and the cheaper every launch becomes. On Earth, a hot chip is a problem. In orbit, it's a feature, and SpaceX owns the rocket.

🇧🇪 Faire des économies pour assainir nos finances est toujours délicat, mais c’est une nécessité. Nous avons mis en œuvre des réformes importantes depuis le début de cette législature. D’autres sont encore nécessaires. Nous le savons et y sommes prêts. Car c’est la condition pour garantir le bien-être de chacun demain. C’est notre devoir d’éviter de plonger le pays dans le chaos. Mais ces réformes doivent être justes. Elles ne doivent pas casser la machine. Elles ne doivent ni enrayer l’activité économique ni mépriser les plus vulnérables. Sans quoi la colère qui se vit chez nos voisins se vivra chez nous avec la même intensité. Aucun département de l’Etat ne peut être immunisé d’un effort. Depuis le début de ce gouvernement, l’essentiel s’est d’ailleurs opéré en compression des dépenses publiques, pas en recettes. Et c’est nécessaire. Mais refuser un juste travail sur la question des recettes, dont l’érosion progressive est un point d’alerte de la Banque nationale, n’est pas crédible. Si on veut pouvoir donner de l’oxygène à ceux qui bossent, respecter les soignants et les pensionnés, assumer le vieillissement de la population et l’accès aux soins, offrir un futur plutôt que des factures à nos jeunes, une contribution des personnes à grande aisance financière est légitime. Ce partage des charges entre les plus aisés et les autres citoyens est un enjeu d’équilibre pour l’avenir. Les Engagés se sont toujours distingués par leur sens des responsabilités. Également par leur refus de traiter caricaturalement les situations vécues par chacun. Et par la défense des enjeux de relance économique, de réussite de la transition, de préservation de la cohésion sociale et de valorisation du travail. Ces enjeux peuvent être rencontrés avec de la bonne volonté autour de la table. Encore faut-il que chacun en témoigne. Aujourd’hui plus que jamais, l’intérêt du pays doit prévaloir sur l’intérêt des partis. Remettons-nous vite à table pour atteindre un résultat juste et crédible et porteur de sens pour l’avenir.

@prevotmaxime pouvez-vous localiser un peu plus précisément "l'érosion des recettes" évoquée dans votre message? (Ici l'évolution sur 25 ans, j'imagine que vous n'evoquiez pas une période plus longue)

We’re glowing with excitement over the new MacBook Pro. You’ve gotta touch it to believe it.

#ETS : Faisons de la décarbonation un avantage compétitif pour notre industrie! L’ETS doit décarboner notre industrie et renforcer sa compétitivité. Nous devons tenir notre trajectoire climatique tout en donnant à nos entreprises les moyens de gagner la bataille industrielle Pour en savoir plus, c’est ici ⬇️ yvanverougstraete.be/actuali…

Depuis la taxe de 3 euros, les douanes belges ont enregistré 82% de petits colis en moins lecho.be/entreprises/produit…

AN APOLOGY DOESN'T ERASE THE INSULT! When it comes to a nation's history and its national symbols, there is no room for shallow excuses or claims of “poor judgment.” Anyone who profits from the Chinese market must first respect the feelings of the Chinese people.