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Joined 4 months ago
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Cake day: July 10th, 2024

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  • Also, can someone please explain how the fuck we wirelessly transmit electricity

    It’s not electricity per se which is transmitted, i.e., electrons which pass through some material (like in cables, or through air when a lightning strikes and the air becomes a plasma through the electric ionization process).

    It is radio waves. Electromagnetic waves of a specific spectrum. Like light, WiFi, TV signals (via antenna), Lasers, etc…
    It is a form of energy transmission.

    There is a whole field about wireless power transfer. One of them some use everyday: wireless inductive chargers for some smartphones or electric toothbrushes. Those rely on the Lorentz force: if you create a varying magnetic field on the one side and have a coil on the other, you can transfer energy. Read up on Lorentz forces and magnetic induction if you want to learn more. Faraday’s law of induction would be another good read.

    Regarding the spacey stuff, that’s trickier. Applying Lorentz principles here on such a scale would be extremely inefficient and probably dangerous as you would need to create an enormous magnetic field. So using focused beams of radio waves has much less losses. Depending on the type of radiation, or wavelength to be more precise, microwaves or even lasers are used for the transmission, whereas microwaves are preferred due to less atmospheric scatterings. They are not allowed be too strong as that would pose several hazards. Instead it has signal strenghts which are safe. To maximize throughput multiple beams could be used.
    Important: this is now electromagnetic stuff, not purely magnetic stuff as with the inductive chargers.

    So how does this work from source to receiver?

    • Source: Sun, emits a shitload of light, other radiation and therby energy.
    • Sunwaves hit photovoltaic panels on the satellite.
    • Panels generate direct currents by this.
    • Direct current gets converted into alternating current (we need this to create electromagnetic beams)
    • AC gets formed into beams (electromagnetic waves such as microwaves) and emitted at a specific location on earth.
    • On earth some form of antenna receives these beams. Due to the way these antennas work, an electric alternating current is generated. (See dipole antenna for a simple example.)
    • This AC needs to go through some transformations to meet some electric specifications to be directly feeded into the elctric grid.
    • Alternatively can be transformed into DC again and directly be used, stored in batteries or, depending on the grid, be feeded into that.

    Done.

    Question, if electricity can be transmitted as a radio signal, why could we generate power here on earth in areas where renewables are super abundant (turbines in the ocean, giant waterfalls, deserts for solar, et cetera) and transmit that around the earth to areas where it’s needed? Why does it have to be in space for this to work?

    In theory, we absolutely could do that. This has some practical limitations though which makes it more complicated and less efficient.

    Transferring energy on a more “horziontal” way on earth would need to overcome a plethora of obstacles like buildings or mountains. Furthermore such long range transmissions would suffer from a lot more atmospheric scattering, be sensitive to moisture and weather conditions etc. Also, we would need to have large antennas and tightly focused beams which is a big technical challenge and would further loose efficiency, especially over long dictances.
    We would also need to guarantee much more “safe corridors” to efficiently transmit without causing harm. And over long distances within the atmosphere the beams must be much stronger to effectively carry enough energy, as much is lost due to scattering, absorption etc… From space a lot of these difficulties don’t exist or don’t have such a large impact. On very short distances should be less of a problem.

    I can imagine, however, transferring energy into space to a satellite, which then forwards it to another receiver at a very different place on earth. Such relay satellite concepts are also not new as I’ve seen. They’ve just not been made yet. But that’s surely just a question of time. They face further challenges, since at each intermediate power station you have energy losses, but they could provide much more flexibility. I don’t see this as an issue which can’t be overcome.

    Sry if this answer isn’t really polished. I tried to convey the most important aspects and am too tired for anything more. Hope this helps.




  • It’s possible to change the language of the article as I’ve seen. Thanks for the link, it was an interesting read!

    I’m glad the girl has not been severly injured. Of course, such things should not happen. The parents must have been extremely worried about their child, let alone how terrified the child was. I hope it won’t stay traumatised from that.

    Yesterday, I’ve also read on another occasion about the other child being rammed by a wolf. I think it’s possible to educate people in a manner such they can deal with their children and pets responsibly in areas where wolf populations exist. Wolves don’t attack humans without reason. According to the article you’ve linked, a behavioural biologist states that the wolf bit her lightly as a warning to stay away. Of course a 5 year old child doesn’t understand this. But it should be possible in this case to implement precautions for the supervisors. Maybe fence off the school ground, get educated how to handle wolf contacts, install auditive deterrents on a frequency only wolves can hear and so on. This can help to improve a peaceful co-existence between humans and wolves.

    It’s not surprising that incidents like these can tilt the public opinion against wolves. Which is why it’s even more important to highlight other non-lethal alternatives as solutions.










  • If it was up to me our industries would’ve never left the country in the first place, and most of the privatizations wouldn’t have gone through.

    Alright, I see it the same way. Still, Germany managed to manoeuvre itself into dependencies of Russia and China, which has shot and still shoots them into the feet.
    I’m totally in favour of trying to find diplomatic ways. But if the call to the talking table is not followed and rather met with aggression on multiple levels, it’s usually the wrong way to give into the demands of the ones who are not afraid to use violence. Therefore, what you see as “funding aggression” is to me a display of resistance. It shows that we will not be bullied into submission, nor will we allow those who use violence to dictate the terms of peace or cooperation.

    nazi like rhetoric going around nowadays. Green politicians talking about “the poison of Islam” [1], which reminds me a lot of the antisemitic rhetoric from WW2 (see “Der Giftpilz” [2]

    I’ve read the article and watched the speech of Katharina Dröge afterwards to get a grasp of the context. As I’ve suspected, the article of the far-right magazine “Junge Freiheit” over-emphasized the “Gift des Islams” part of her speech. It’s just typical click- & ragebait again and a very misleading headline. At least the article itself somehow manages to not completeley misrepresent her actual speech.
    If you’re interested, you can currently watch it here: https://www.ardmediathek.de/video/phoenix-parlament/katharina-droege-in-der-generaldebatte/phoenix/Y3JpZDovL3Bob2VuaXguZGUvNDU4NjA2Mg
    You’ll probably notice as well that this was a rather minor phrasing. More importantly, it was embedded in and directed towards islamism, i.e., people radicalized to the point of becoming murderous, which has to be prevented of course. In the same speech she is emphasizing the importance of asylum for all of those who have suffered the worst and don’t become radicalized criminals.
    Given this context and the fact that the German Greens are usually considered a rather left-leaning political party, I find the comparison to ‘Der Giftpilz’ not only vastly misplaced but also ridiculous.

    Besides that, Germany didn’t denazify properly after WW2 anyway (“Persilscheine”

    Thanks for pointing out the “Persilscheine”. Despite the tremendous amount of “Nazis evil”-content in school, especially in history classes, this wasn’t a topic. An educational gap I’m eager to fill soon.
    Regarding the statement of unproper denazification I can’t add anything to that besides personal impressions which have no value for general statements.

    The chancellor talking about “deportations in big style”. The CDU trying to ban refugees from going to any public events. And these are not even the nazis in the AfD. It might be 2024, but mentalities haven’t changed much, we’re just picking other out groups to stomp on, mostly because we’re not tackling the real issues at heart.

    Yes, yes. This is indeed really bad. From my point of view the big old parties SPD, CDU/CSU are fearing for their public support. And instead of trying to address the real issues, they’re mimicking talking points of the AfD. The latter, unfortunately, becoming increasingly popular in many areas of Germany.
    I wonder why that is.
    No, I don’t.
    (Okay, people being too incompetent to critically think about media adds to that.)

    However, I wouldn’t go as far as to say, that the mentalities haven’t changed much in all that time since WW2. Three generations were raised since then with the fourth one reaching maturity. And there is still a tremendous amount of people who are not sharing the same xenophobic idiotism propagated by AfD, CDU & Co. It’s not too late to prevent the mistakes of the past.

    But again, to get back on China, Germany is very well conducting major business with a ton of authoritarian countries, stomping on workers’ rights all across the world just to enrich German companies, and thus I won’t take their virtue signalling for anything more than just virtue signalling.

    I’m also not really happy about that. It’s one devil replaced by the other. However, there are different shades to that. At least the one devils have not launched a full-scale war. And now Germans have started to question their dependencies on foreign countries a bit more. But of course it can’t be a long-term solution to keep things as they are now.

    I’ll take virtue signalling. “It’s something”. Besides, the current government is the most productive since the Merkel-era and has initiated and achieved many good things. Although I agree that regarding foreign affairs it could be better. Most progress was achieved in domestic affairs.

    I’m here just pointing out the hypocrisy. If they care so much about Taiwan, they should at least make it clear that it is due to geostrategic interests, not because they suddenly found their love for democracy and what not other nonsense.

    And people love hypocrits. If someone says the one thing, but does the opposite, does it make them wrong in what they said?
    How about we criticise the bad and praise the good?





  • The level of your argumentation:
    Are you a firefighter or a medical doctor? If not, you’re obviously in favour of fires, death and disease.
    Why aren’t you donating all of your stuff to homeless people? Or are you happy all those people don’t have a home?
    Why aren’t you saving the world already???

    You know, demanding change and maybe showing some sort of protest does not mean you need to do those things exactly as you would like to see them, especially if those efforts wouldn’t change anything on the larger scale and rather lead to a bunch of problems in your life.


  • Why do they get attacked though?

    Edit: got time to read he article:

    Many of the assaults are caused by the shortage of hospital staff and family members’ frustration at the resulting long waiting times for surgery and consultations.

    According to the doctors’ union ANAAO, until 2022 almost half of positions in emergency medicine were vacant. Salary-cap legislation over the past two decades to curb public spending has kept salaries low, and work schedules are punishing. For many Italian medical staff, the Covid pandemic was the tipping point, accelerating an exodus abroad. Spending plans published by Giorgia Meloni’s government envisage further healthcare cuts.

    In 2023, according to the Forum delle Società Scientifiche dei Clinici Ospedalieri e Universitari Italiani, there was a shortage of approximately 30,000 doctors in Italy. Between 2010 and 2020, 111 hospitals and 113 emergency rooms closed.

    Yeah, sounds totally reasonable to put soldiers in hospitals in order to solve these problems. /s smh