PhD in aerospace engineering from Wallonia.

Docteur ingénieur en aérospatiale de Wallonie.

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Joined 1 year ago
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Cake day: June 12th, 2023

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  • When we look at the sky, there is a line where there is way more stars than usual. This line goes all the way around the sky. This was called the milky way by the Greeks because it was like a road sparkled with milk drops. At some point, we deduced that we were in a group of stars arranged in a flat disk. Later, we realized that some weird space clouds (nebulae) were much further away than we thought and were actually other huge groups of stars like our own that we named galaxies, still after milk.

    There are more details me course. Even along the line in the sky drawn by the milky way, there is one side where there is much more stars and dust than the other. We deduced that we were at the edge of the disk and the bright region was the center of our galaxy. Also, the amount of gas and dust that block certain types of light that teach us that our galaxy has arms.









  • Quantum entanglement is closely related with another quantum phenomenon that you might already know: the superposition principle. Let’s say that I have a particle. My particle spins on itself. If I measure its spin, it can either spin to the left or to the right. I cannot know in advance whether it will spin to the left or to the right. And it’s not just a lack of information because we can create an experiment in which the different spins of a single particle can interfere. We say that the particle’s spin in a superposed state of both left and right, until we measure it.

    Now there’s already a good thought experiment that explains quantum entanglement: Schrödinger’s cat. I have trapped a cat in a box, and I have installed a cruel setup inside. There’s a detector in which I can enter my particle. If it spins to the right, the detector breaks a bottle of poison that kills the cat. If it spins to the left, nothing happens. Importantly, the detector does not communicate the measurement to me.

    Now, I insert my superposed particle inside the detector and don’t look at the result. The particle exits the detector and I can keep it. Because my particle was in a superposed state, I don’t know wether the detector has measured a right or left spin. I don’t know whether the cat is dead. Once again, it’s not just a lack of knowledge because I could imagine an experiment in which its dead and alive state interfere.

    Now imagine that I make a measurement of the particle’s spin and it measures right. Then, I am 100% certain that the cat will be dead once I open the box. Even though both the particle and the cat were still in superposition, once I measure one, I will know the state of the other. That’s quantum entanglement.

    It’s important because we can use this interaction between quantum objects to copy and paste information in a quantum computer without making a measurement. A measurement would damage the quantum information because it would collapse the superposed state.





  • thedarkfly@feddit.nltoAsklemmy@lemmy.mlDo you use adblock? Why? Why not?
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    1 year ago

    Of course. And I’ll continue to do so as long as advertisement is detrimental to my online experience. If it wastes my time by forcing me to watch an ad before a video, if it distracts me from reading a text because of animations, if it tries to scam or shock me, I’m better off blocking it. I’m not against advertisement as communication that a useful product or service exists, I’m against advertisement abuse and greed.

    I’ll happily pay for, donate to, or otherwise support services important to me that need and deserve it.