Can you explain please, where I made a mistake?
Your mistake is thinking Earth is 6km in radius! :D 6km is how far you walk in an hour. Either you think Earth 1000 times too small or kilometer 1000 times too big.
For an object heavier than the Earth, 1g radius will be greater than the radius of Earth. For 56 Earth masses that's sqrt(56) times bigger = 48000km.
A 56 Earth mass black hole will take 5.5e55 years to evaporate according to this calculator. A 100kg black hole (more close to what Richard used to be) is much smaller than the nucleus of an atom and will evaporate in 0.05 nanoseconds.
Curiously there was a paper recently that calculated that even if there was a small black hole in the center of the Sun, it would take millions of years for it to grow, because the aperture is so small not much can fit through, and the infalling gas heats up so much as to repel the rest, creating an internal hot bubble.
I pick up street litter, and having picked up thousands of pounds, I have never felt that loose caps are a problem, let alone one that requires such a solution. The number of littered bottles, with or without a cap, is greater than the number of loose caps, and the amount of plastic in every bottle dwarfs the plastic in a cap. Fixing the cap to the bottle will do nothing to improve the recycling rate of plastic if entire bottles are already tossed anyway.
I consider the idea of cap tethers as adversarial memetic warfare thrust upon us for some unknown ulterior purpose, possibly to make us hate the very idea of environmental consciousness. Same as paper straws. I like plastic bag bans though.
As far as picking litter is concerned, I personally prefer finding bottles without a cap. At least those are empty, all liquid having evaporated after the bottle has spent several months in the bushes. The capped bottles are often half-full and are just nasty. (Who even pays for a bottle of drink and not drinks half of it anyway?)
It is important to remember that, unless accompanied by convincing evidence for selective advantage, any single inheritable trait is more likely to have arisen from genetic drift, not from natural selection! There is, in my opinion, too much focus on conversation about superficial phenotypic traits like "shape of the nose" this and "angle of the eye" that, all the arguments about how one is better than another. Could the asiatic epicanthic fold give advantage against icy winds? Maaaybe... But it doesn't even have to. What about the asiatic dry earwax gene? You'd struggle to even come up with a story of how dry earwax or wet earwax is actually better under certain conditions, or you could just say "it's a single nucleotide polymorphism that could have spread by genetic drift" and be done.
Very few human traits have definitely been naturally selected for: light skin in non-sunny climates for better vitamin D production, sickle cell gene for malaria resistance, lactase persistence for animal milk consumption. Even there, the estimated selective advantage is actually much smaller than you'd expect: lactose tolerance confers only something like 1% advantage! There are many more possible neutral mutations than advantageous ones, and each one has a chance to be fixed in the entire population by genetic drift, meaning that any widespread human trait that is less clearly advantageous than lactose tolerance is more likely to be neutral than advantageous at all.
Even mildly disadvantageous mutations can be fixed by genetic drift, especially in humans since we have had many bottlenecks and founder effects. There was an area in Appalachia populated by blue-skinned people due to founder effect. No one is going to try to argue how having blue skin was actually advantageous for them to blend into their environment! There is an area in Dominican Republic with a very high rate of children born intersex, again due to a founder effect mutation. They are not considered exceptional and live normal lives as their culture has adapted to treat them as routine, as a kind of third gender. But they are not some kind of new level of human evolution, an adaptation for an intersectional era!
The only mutations that definitely cannot spread by genetic drift are those that definitely kill you.
I knew that motion sickness is triggered by frequent starts and stops and frequent turns, but even I was not aware of how big a contribution the engine vibration makes until I got to experience a ride without it.
I was apprehensive about EVs but the first time I rode in one I immediately fell in love with it. I get carsick easily, and the super-smooth ride without the chug-chug-chug of an internal combustion engine made the experience surprisingly much more pleasant for me. I do not use a car, but if I had to buy one, I don't think I could ever stomach an ICE again knowing that this alternative is available.
One example: on May 30, 2020 in Minneapolis, during the protests after George Floyd killing, some police were driving around the streets in an unmarked van, shooting at pedestrians at random without stopping. They later claimed they were shooting rubber bullets to "encourage" people to obey the curfew order. Of course, if you are the one being shot at in a drive by from a mystery van, you have no time to determine what kind of bullets are being fired... One pedestrian shot back! There is a video of it.
The guy was immediately arrested, miraculously without being shot to death in the process, and put on trial, but acquitted due to justifiable self-defense. The police did not drive around shooting randomly any more after that though. I see the guy even won a $1.5M lawsuit against the police now!
This is a great gotcha! I just recently learned that 700C, the "29er", and (some) "28 inch" are all the same wheel.
To be fair, when I was little I too was guessing that "C" stands for centimeters or something metric. Now I know that "C" in "700C", the most popular road/hybrid wheel size, stands for the third size in the French "ABCD" notation, where sizes "700A", "700B", and "700D" are obsolete and are no longer manufactured.
I'd love to use ISO sizes, but even if I know that I need a 40-622 wheel, there is no way to search for it on the storefront if every single seller made gross mistakes in labeling their product! I have to ignore the specs shown entirely and make educated guesses based on title alone. For example "WHEEL AL 700 FRONT ALEX AP18 QR Silver UCP" in the picture is almost certainly a 700C wheel and NOT an 18-inch wheel. The "18" in the title probably stands for 18mm rim width, which means that this wheel will fit my bike and tire, but is a bit more narrow than ideal 23mm. The sellers must be copying the title verbatim from the manufacturer, and then haphazardly filling out the specifications without knowing or understanding the actual numbers. The ISO size is not mentioned at all.
Given a radiative forcing coefficient of ln(new ppm/old ppm)/ln(2)*3.7 W/m**2 I have previously calculated that for every 1kWh of electricity generated from natural gas, an additional 2.2 kWh of heat is dumped into the atmosphere due to greenhouse effect in every year thereafter (for at least 1000 years that the resulting carbon dioxide remains in the air). So while the initial numbers are similar, you have to remember that the heat you generate is a one-time release (that dissipates into space as infrared radiation), but the greenhouse effect remains around in perpetuity, accumulating from year to year. If you are consuming 1kW of fossil electricity on average, after 100 years you are still only generating 1.67kW of heat (1kW from your devices and .67kW from 60% efficient power plant), but you also get an extra 220kW of heat from accumulated greenhouse gas.
I have wondered this question myself, and it does appear that the heat from the fossil/nuclear power itself is negligible over long term compared to the greenhouse effect. At least until you reach a Kardashev type I civilization level and have so many nuclear/fusion reactors that they noticeably raise the global temperature and necessitate special radiators.
I wanted to go with this, but had to go even bigger. The largest mine truck according to the wiki is BelAZ 75710 (as seen in the picture) which has "59/80R63" tires that are merely 402.7cm big.
Trying to buy right size bicycle wheel online
Needed a replacement 700C front wheel for my commuter bike after the old aluminum rim exploded like a looney tunes cannon. It's hard enough to find the right size when there are 3 competing tire/rim sizing systems currently in use, it doesn't help when the people selling the wheels have no idea what the numbers mean either! All of these examples are from separate storefronts at the big online store. Ended up buying the wheel identical to mine from my local bicycle shop at the same price as online and with no shipping fee or delivery time.
The 3 systems in use are the American customary inch fraction notation like 26x1+3⁄4 (which is NOT interchangeable with American customary inch decimal notation like 26x1.75), the French metric notation like 650x45C, and the ISO 5775 metric notation like 47-571. I found the wikipedia conversion tables and Sheldon Brown's tire size chart invaluable.
By some argument, section 103 of the DMCA (which is what grandparent post is referring to) does make it illegal to even talk about DRM circumvention methods.
illegal to: (2) "manufacture, import, offer to the public, provide, or otherwise traffic in" a device, service or component which is primarily intended to circumvent "a technological measure that effectively controls access to a work," and which either has limited commercially significant other uses or is marketed for the anti-circumvention purpose.
If youtube implements an "access control measure" by splicing the ads with the video and disabling the fast-forward button during the ad, and you go on a forum and say "Oh yeah, you can write a script that detects the parts that are ads because the button is disabled, and force-fast-forwards through those", some lawyer would argue that you have offered to the public a method to circumvent an access control measure, and therefore your speech is illegal. If you actually write the greasemonkey script and post it online, that would definitely be illegal.
This is abhorrent to the types among us for whom "code IS free speech", but this scenario is not just a hypothetical. DMCA has been controversial for a long time. Digg collapsed in part because of the user revolt over the admins deleting any post containing the leaked AACS decryption key, which is just a 32-digit number. Yet "speaking" the number alone, aloud, on an online platform (and nothing else!) was enough for MPAA to send cease and desist letters to Digg under DMCA, and Digg folded.
Physical players disconnected from the internet can still receive offline firmware updates included on the discs themselves. The moment you insert a new disc, it automatically executes BD+ code that in theory could patch the firmware to blacklist an arbitrary old disc that you own. This has never yet happened with a previously-legal disc, but then again for example Amazon has never deleted purchased copies of the 1984 book from customers' kindles, until one day when it did.
a standalone drive
Another cool/scary feature of the BluRay spec is offline firmware updates (called BD+). Any disc can contain code that runs automatically and can patch the player firmware or execute arbitrary functions. So if you have an older hacked player and you insert a newer disc into it, the AACS Consortium has the ability to brick it. Or if you "own" an older disc but the Consortium starts to dislike it for some reason (maybe they discovered that the disc was printed by a pirate publisher, or maybe there was a retroactive licensing dispute), they can include code on every newly published disc that blacklists the old disc. Even with a standalone player that you never connect to the internet, the moment you insert any new disc into it, your old "problematic" disc will be unplayable. This has never yet happened with a previously-legal disc AFAIK, but it is possible within the spec. Every player manufacturer must obey the spec and implement the BD+ virtual machine in order to be allowed to read AACS content. And if you hack your player to ignore BD+ code, then the newer disc will not play because its content may be scrambled in a way that only the custom BD+ code included with it can unscramble.
What’s your solution?
How about we put a metal box in front of the house to put the mail in, big enough for a package, and put a lock on the box such that the delivery person can put the package in but no one can take it out unless they have a key for the lock. You would carry the key around with you.
The credit companies do not insure against fraud, they simply take the money out of the merchant account and put it back into yours. Now it's the merchant who has no recourse, if they have already shipped the product. So the only difference between CC and crypto is who is typically left holding an empty bag in case of theft - the payer or the payee. Certainly not the banks!
I'd argue in terms of assigning responsibility, it seems more fair to expect you the customer to keep your digital wallet secure from thieves, than to expect the merchant to try guess every time whether the visitor to their online store happens to be using a stolen credit card.
Question: do the Japanese actually care about privacy? I know I do, but if you were to ask a Japanese person why does their country use cash, would they say "We have considered a system of payment cards and decided against it for privacy reasons" or would they just shrug and say "I dunno, I'm not in charge of payment systems, I use what I have"?
Browse through 4096 concepts identified within a 512-node toy neural network
To better understand how neural networks function, researchers trained a toy 512-node neural network on a text dataset and then tried to identify features within the network that are semantically meaningful. The key observation is that while individual neurons are difficult to attribute specific functionality to, you can find groups of neurons that collectively do seem to fire in response to human-legible features and concepts. By some metric, the 4096-feature decomposition of the 512-node toy model explains 79% of the information within it. The researchers used an AI nicknamed Claude to automatically annotate all the features by guessing how a human would describe them, like for example feature #3647 "Abstract adjectives/verbs in credit/debt legal text", or the "sus" feature #3545. Browse through the visualization and see for yourself!
The researchers called the ability of neural networks to encode more information than they have neurons for as "superposition", and single neurons being responsible for multiple, sometimes seemingly unrelated, concepts as being "polysemantic".
Full paper: https://transformer-circuits.pub/2023/monosemantic-features/index.html also discussed at: https://www.astralcodexten.com/p/god-help-us-lets-try-to-understand and hackernews: https://news.ycombinator.com/item?id=38438261
The real double-slit quantum eraser they don't want you to know about!
The recent post made me fear that a lot of you are taking this "monkey looks at double-slits" meme, which was only ever supposed to be a funny monkey meme, actually seriously. Honorable mention goes to @[email protected], whose 12 posts on the topic, insisting that the quantum eraser experiment (but not the delayed-choice quantum eraser!) proves that the double slit is somehow bizarre, forced me to make my own meme. This meme explains the (non-delayed choice) quantum eraser paper from arXiv:quant-ph/0106078 and the figures are numbered to reference the paper.
First of all, looking at the photons, you the conscious intelligent monkey, MAKES NO DIFFERENCE. You can't actually "see" the photons going through a slit the way you could see say a bowling ball. The only way to detect a photon is to absorb or reflect it, and if the photon is getting absorbed by your eye that means it's not going through the slit or hitting the screen. The interference pattern stays visible on the screen WHETHER OR NOT YOU LOOK AT IT.
They've lied to you when they said the pattern changes when you "look" at which slit it the photon goes through. What the physicists actually do to measure the "which path" information is they put these circular polarizer filters in front of the slits, one clockwise one counterclockwise. Then the pattern disappears and you get this one single blob of density (Not even double! Figure 3). This is because light polarized in opposite directions cannot interfere with itself - wikipedia calls this the "Fresnel–Arago laws". In principle you could have put a polarization detector in place of the screen and record which way the light hitting it is polarized, which would tell you which slit the photon must have went through. The physicists DON'T EVEN BOTHER DOING IT. The fact alone that the light is polarized when it hits the screen is sufficient to destroy the interference pattern.
Well, NO SHIT. You put these giant 3D glasses in front of the slits and you still expect to see interference? This is very much a "mechanical interaction", not some "non-obtrusive conscious observation". Everything that destroys coherence will ruin your quantum experiment! Mystery solved!
So what about the quantum eraser, @kromem will ask? Popular science has created this myth that you can look at the screen and you can make the interference pattern literally shimmer in and out of existence by just flipping a switch, connected to second detector positioned elsewhere, turning it off and on. An action at a distant place (the detector POL1 observing "twinned" entangled photons created by this fancy nonlinear barium crystal before the slits, Figure 1) changes whether light over here behaves as a particle or a wave, right in front of your eyes. Spooky action at a distance, right?
THIS FUCKING DOESN'T HAPPEN. The monkey will see the single blob from Figure 3 and only single blob, no matter whether it turns the second detector on or off! The interference pattern will NEVER shimmer back into existence. The light never switches between behaving like a wave and behaving like a particle. It always behaves the same way, all the time, everywhere in the universe - like fucking light!
So what do the physicists actually fucking mean when they say the interference pattern is "restored"? If you observe the photons hitting the screen one at a time and you correlate them with simultaneous detections at detector POL1, you can mark those events as either "yes coincidence" category A or "no coincidence" category B. If you look at just all the category A events (Figure 4) you will see an interference pattern, and just category B you will see another (Figure 5). You cannot see these patterns by eye on the screen! You have to use a computer to record the events individually and separate them, you will only ever see a single blob by eye. The two interference patterns are subsets of that blob. They were always part of it, their hills and valleys mesh together into a single continuum. NO ONE EVER FUCKING EXPLAINED THIS.
The detector POL1 has a linear polarizer filter in front of it, so straight out the gate it will not see 50% of the twinned photons at all, because they will get stuck in the filter. Your category A can never match more than 50% of events. It gets worse, since the non-linear crystal in reality has very low efficiency and most photons going through are not twinned, so you cannot measure category B directly. In the experiment they do it by rotating the filter 90°, which changes the correlation to category B. In the meme I show them as if the crystal was 100% efficient.
The delayed-choice quantum eraser works similarly - you only ever see a single blob and can never see the interference pattern shimmer in and out of existence. You need the correlation data from the second detector to split the blob into two intermeshed interference patterns using a computer. The Sabine video was the first one I've ever seen that explains this correctly. Every other popular science video up to that point has lied to me!
Whatever you do, DO NOT watch the DR. QUANTUM video with an open mind! (Not even going to link to it, @manual3204 linked it in the other thread.) It's from a documentary produced by a literal UFO cult to promote their quantum woo woo, only masquerading as a quirky science video. It came out in the early days of youtube, when its production and animation quality were unusually high for its time, so it immediately became youtube's go-to video for double slit experiment. Copies of it remain highly ranked there even to present day. It's total baloney!
This fast food order kiosk accepts cash
All the McD*nalds in my area have been upgraded with order kiosks. Regardless of all the controversy around self-checkout, and minimum wage, and automation taking our jobs, I personally love them. I can take my sweet time composing my order, I can see the full selection (such as it is), I can see pictures and prices clearly without having to strain my eyes to read 12pt font on the tableau, and I don't have to shout at the cashier to be understood or struggle to hear back. I really believe this is the right way forward.
My only complaint so far has been that the order kiosks only accept card. There is actually a way to pay by cash that the machine never lets you know about - you have to press "cancel" on the keypad when it asks to insert card, and then the screen gives you an order number to give to the human cashier (each store still has one register open) so you can pay in cash. So I still have to wait on line, but at least my order selection is locked in, I can have exact change ready, and there isn't usually a line anyway anymore.
I know all yall Europeans are proud about your nearly total transition to cashless economy or whatever, and you like to boast how not a single euro banknote has graced the inside of your wallet in months. However I personally like cash, and I genuinely believe that a cash payment system is a necessary element of a liberal democracy and secure society. So at least understand my pleasant surprise when I saw these reverse-ATM cashboxes at this restaurant. They work and were being actively used too! (It spat out my dollar coins though, those bastards!) I hope they find their way into more places.
In terms of kWh per kWh, by how much does greenhouse CO2 from running an air-conditioner heat up the rest of the Earth?
It is said that ACs are counterproductive in fight against global warming, in that while they may make the local environment temporarily livable, the greenhouse gases produced while making the electricity needed to operate them heat up the rest of the Earth by much more than the relief from the AC itself. By how much exactly is that? Note that here I am interested in the global impact of greenhouse gases specifically, not in the local heat island effect (given how ACs do not destroy heat but only move it from inside to outside, and add extra heat from running the compressor itself). Let's also assume all electricity comes from fossil fuels (ACs might become a viable solution if 100% of AC electricity came from renewable solar, which is actually a reasonable goal to strive for given how both AC and solar are most active during the day, but at the moment most of electricity delivered to me specifically, for example, comes from natural gas.)
Here's my estimate. Let me know if it is reasonable! Methane has energy density of 891 kJ/mol, burnt into CO2 at 1 mol : 1 mol. Gas turbines have efficiency up to 60%. The radiative forcing of CO2 can be calculated as: ln(new ppm/old ppm)/ln(2)*3.7 W/m**2. For example the 131 ppm increase in CO2 since 1750 up to 411 ppm has a radiative forcing of 2.05 W/m**2 (is that across the entire Earth's surface? or only its crosssection?), and CO2 has persistence in atmosphere for at least 1000 years. The atmosphere composition is 78% nitrogen 21% oxygen 0.9% argon so its molar mass is:
.78 * 28 g/mol + .2132 g/mol + .00918 g/mol = 28.7 g/mol
And total atmospheric mass:
43.14(6.37e6 m)2 * ~10000 kg/m2 * 1000 g/kg / (28.7 g/mol) = 1.78e20 mol
Suppose 8 billion people each run 1kW AC for 1 year, with electricity from natural gas. (That's similar to our total current global energy consumption of 20TW, though of course we use power for things other than just AC or electricity, but also most energy comes from coal and gasoline not just gas, and 80% comes from fossil fuels not renewables.)
8e9 people * 1000 W/person * 606024*365 s / (891e3 J/mol * 0.6) = 472e12 mol
That's 472 teramols of CO2 (20.8 gigatons) added to the atmosphere each year, or 472e12 / 1.78e20 * 1e6 = 2.65 ppm (parts per million). It is believable that having done so for a hundred years we have raised CO2 concentration from pre-industrial levels up to 411 ppm. The radiative forcing is:
ln((411 ppm + 2.65 ppm)/(411 ppm)) / ln(2) * 3.7 W/m2 = 0.0343 W/m2
Or for the whole earth:
43.14(6.37e6 m)2 * 0.0343 W/m2 = 17.5 TW
What is my individual contribution for 1 hour?
17.5e12 W / 8e9 / (24*365) = 0.25 W
That is, if I run my 1kW air conditioner for 1 hour, the entire Earth will be solar heated by an extra 0.25 W for the next 1000 years. That doesn't sound like much, but it adds up over time: I spent one kilowatt-hour in one hour on cooling, but the rest of the Earth will be heated by an extra 0.25 W * 24*365 hours = 2.2 kilowatt-hours in the next year, and again every year thereafter. Multiply that by 8 billion people or a hundred years and it adds up a lot, even considering the heat is distributed across entire planet surface not just areas where people live.
So my answer is 1 kWh of cooling = 2.2 kWh of heating per year for the next 1000 years. By same calculation in terms of mass, 1 kg of CO2 = 7.4 kWh of heating for every year thereafter. Is this accurate?
Cowboys in westerns always have standoffs because the one who draws first attempts murder, to draw second is justified self-defense
Everyone is armed all the time and that's normal, but to draw a weapon is an overt hostile act. A standoff therefore is a game of chicken because both want to kill each other and you want to draw first to have the highest chance of surviving, but even a bandit will hesitate to add a felony murder charge to their rap sheet. The whole town serves as witness when there is a pair of eyes behind every shuttered window. The hero always draws second, both demonstrating his superior skill and speed by defeating the opponent even at a disadvantage, and getting away with murder scot-free.
The First Room-Temperature Ambient-Pressure Superconductor
cross-posted from: https://lemmy.world/post/2144441
> Huge if this is true. > Claim is: They have attained superconductivity at room temperature and ambient pressure. Also superconductivity holds till 127 C.
> There is a discussion on Hacker News
Mixed nuts for me, not for thee
Image description - Cuphead Rage Flower meme Me seeing cheap and expensive nuts mixed together for sale on the shelf Me buying expensive nuts and mixing in cheap nuts myself
[Edited for CAPSLOCK]