This all seems as exotic or esoteric to us now as these invisible electromagnetic waves were to Heinrich Hertz, who reportedly regarded them as mere scientific curiosities with no practical applications.

Unable to foresee radio, television, telephones, remote controls, microwave ovens, Wifi, Bluetooth... you get the point, that "thing with no practical applications" is now a staple of daily life, and all around us. We have fully tamed Electromagnetism.

Now with things like Quantum Computing and Bose-Einstein Condensates, we are starting to tame a new esoteric scientific curiosity - the probability wave function, the Uncertainty Principle.

Heinrich Hertz did not foresee things like satellite television and Spotify while looking for a spark flying across two metal tips from his dark room in the 1880s, but surely we have a better grasp of what potential benefits the newest technologies have in store for humanity?
Or are we for the most part still in the Hertz-like naive fiddling process?

Either way, there is going to be some incredible magic inside that quantum box!

I'm gonna eat that motherfucker, so I need to be sure. Can birds, cats and dogs also eat them?

Edit: my cat sneaked into the room and ate a bit of a leaf, the same size I had tried myself yesterday. We dead, I'm typing from the afterlife. I tried uploading an actual photo of my plant but lemmy won't let me.

Obviously, I've heard of table salt (NaCl), but I've also heard of others substances being called salts. What do they mean by something being a salt?

There's the regular Clorox bleach that we use with whites, but then there is non-chlorine bleach. What is a bleach?

I've long toyed with a mid-life pivot into a different field. Mostly, I lean towards IT as the most practical for me, but I love the idea of finally studying a hard science, which I grew to love, but never really got a good formal education in.

I've heard/read, for example, that there aren't necessarily tons of astrophysics jobs out there, so if you only have a bachelor's degree, you might have a tough time. I don't even know that this is true, but I use it as an example.

What are the hard science fields that would be the opposite of this? I could imagine there might be a lot of Chemistry-related jobs, for example, maybe? But I have a hard time imagining what you could do with a pure Physics degree (without also focusing on Engineering or something supplementary)? Would Biology get you anywhere by itself?

Or is it just the hard truth of all hard sciences that you're pretty much worthless with just a four-year degree, from a job perspective?

I live in Vancouver Canada, my house was built in the 1950's and the basement has the floor joists of the kitchen [above it] exposed.

At that time forestry here was felling massive ancient trees. I'm curious how precisely I can establish a maximum age of the trees felled.

Obviously I could count the rings visible on the joists and subtract that number from 1950, but not having the tree's full diameter limits measurement. I understand it's possible to compare relative ring sizes with existing [cross referenced] data sets to date timber.

Does anyone have any experience doing this or able to point me in the right direction? Any resources I'm unlikely to find on Google?

I understand that hurricanes get their strength from warm ocean water but do they take a measurable amount of heat from the water? ('Not going anywhere with this question, just wondering.)

My 8-year-old son asked this question and i couldn't give him a definite answer. So he's wondering if it would do the same thing as a balloon pushed underwater in the bathtub (which kind of makes sense to me, due to the density differences, not just gravity alone).

But I told him I'd ask those more knowledgeable than me.

What might prevent metal "blowing" and other forms of shaping from working if gravity was not a factor? Let's handwave-ignore the extremes of temperature as it relates to techniques and the present primitive space habitats and craft.

Is it possible to suspend a pool of molten metal, with a tube inside, spin while adding a gas to shape a container, and form more complex shapes through additional heat cycles in a repeatable process?

OK, I had a hard time coming up with a single sentence title, so please bear with me.

Let's assume I have a computer with a perfect random number generator. I want to draw from a (electronic) deck of cards that have been shuffled. I can see two distinct algorithms to accomplish this:

1. Fill a list with the 52 cards in random order, and then pull cards from the list in sequence. That is, defining the (random) sequence of cards before getting them. This is analogous to flipping over cards from a the top of a well-shuffled deck.

2. Generate a random card from the set that hasn't been selected yet. In other words, you don't keep track of what card is going to come up next, you do a random select each time.

Programattically I can see advantages to both systems, but I'm wondering if there's any mathematical or statistical difference between them.

I'm researching all of this, and it seems cats are the main(?) host for T. gondii. And yet it can infect humans as well. As far as I know, it does (sometimes) virtually nothing except either maybe give you schizophrenia or make you a "Risk-taking Asshole" for lack of a better term. What is even the purpose of doing this to infected humans??? WHY??? What kind of parasite infects a human with the only real side effect of "I'm just gonna make you gamble a lot and give you road rage."

Obviously there's other, more serious side effects. But I truly don't understand what its goals are once it comes into contact with humans. Are we just another body to them? A scenario of "Oh well im in this human now so... Guess I better get comfy or whatever."

Keep in mind I'm aware the Parasite isn't like a person, it doesn't just "do stuff" the way we humans do. It can't really think. My confusion stems from why it even bothers evolving just enough to be able to infect humans in the first place. Why doesn't it just stick with cats? And when it does infect humans, why does it just- not do anything half the time? It's like it only infects people Internally just to mildly inconvenience them.

tl;dr don't bother. This is too abstracted and nuanced. That is okay to skip.

I like to understand the abstract scope of engineering. This is way beyond the simple surface level, with pics below to illustrate my point.

With electric guitar pickups, the complexity of field shaping and design control over the sensor seems like a place where optimising the profitable manufacturability of the final product remains the primary constraint with little deviation.

I struggle to qualify and quantify my intuitive hunch that there is a whole lot more potential to engineer something new and better within the realm of modern manufacturing. I don't know the principal questions I should ask or what might disprove my ideas from the get go.

• Most transformers shape the magnetic field far more than guitar pickups.
• a guitar pickup appears to be more of a two dimensional sensor that picks up the motion of a ferromagnetic string in the two primary directions of motion
• there are more complex harmonic motions present than a pickup can register in two dimensions
• the coil and slugs of a pickup are surrounded by a single large winding, yet the strings each have very different frequencies
• it is now possible to make a powdered ferrite core of nearly any shape and frequency
• the traditional pickup has little effective shaping of the magnetic field path
• guitar pickups are not optimised to a point where they are readily used elsewhere in other sensory applications and devices as economy of scale should dictate in an open and manipulation free market... I don't think they are anyways
• what might be the result if a 270° toroidal powdered core were designed and shaped for each string while tailoring the copper winding and ferrite for each string's mean frequency and shielding each of these
• would a chord segment gap in a toroidal core pick up more 3d motion from the string
• what effect would a primary and secondary winding wound in the opposite dot notation direction have on the pickup of more complex harmonics and motion
• why does none of this matter due to the filtering of LCR and the noise floor or other aspects

Like here is the basic range of commercial products:

The typical schematic of operation:

Basic construction:

This is a typically low noise toroidal transformer that has been around for ages:

Now I need you to abstract this concept with me a little bit. Imagine if a small toroidal core was below each string and offset towards the neck or bridge so that they will fit. Nothing would stick out or surround the string. The 270° is not a radius cut like a pie. Instead it is a chord and removed segment:

There are totally random pics from DDG that are somewhat illustrative in abstract:

These are just some random powdered core ferrites that illustrate how these can be formed into any shape now:

I usually avoid anything audiophile related because it draws out pseudo science nonsense like crazy, but at the center of this question is really a desire for a deeper understanding of sensors and magnetics that have much broader applications in precise motion control and sensors for a range of equipment.

In a higher level of abstraction, I'm also really asking when and where does this subject become the realm of the illusive bearded nude virgin demigods that get enslaved to corpo NDA masters from birth. ^.5^/s

I've noticed something interesting that I cant get an answer to online. Whenever I leave out watermelon in my house (After eating it of course. I cut slices from the melon so what gets left behind is the rind), it attracts lots of gnats and flies without failure. After cutting and eating a Yellow Watermelon for the first time and then leaving it out, There wasn't a single fly that cared for it, it was never swarmed or landed on or fed upon. it just sat there for a day or so before I finally threw it out.

Why is this?? Repeating this same scenario always gives me the same output. The flies aren't attracted to the Yellow Melon, Why?

I know animals can have limbs surgically replanted and still work. But can the same be said about plants? Could I cleanly cut down a tree, then stick it back on, and have it still grow into itself?

I couldn't find anywhere that would tell me what kind of motor is usually used there. And I don't know enough about motors to be like... well of course it's this kind... But once I know what it is... how does it work? Like different adjustable bases move different intervals for a single push of the remote button (at least according to my wife). So that got me thinking, what controls the minimum interval of difference between two positions the motor will support? I don't hear clicks, so I don't think it is a ratchet type thing which would have a clear min interval. Yet, if you unplug it, it doesn't just go flat. So there must be some sort of passive hold mechanism of some type...

Sometimes, when I'm really cold, it can take over an hour to warm me up, even with a heating blanket. The quickest solution, a hot shower, feels really inefficient with all the heat going down the drain.

That got me thinking about microwaves. They heat food (partly) from the inside, contrary to simple infrared radiation.

Could we safely do that with people?

I found a Reddit thread where a non-lethal weapon and people getting eye damage because they stayed too long in front of a radar dish.

Could some sort of device be made that would warm specific areas (say, a hand or a leg) without endangering sensitive areas like the eyes?

Would it actually warm someone up from the inside? Would it be possible to make it safe?

Would it present advantages in cases of hypothermia, compared to heated IV fluids?