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How do you determine what is a good district or not?

Agreed. The argument "I want to know if my child is safe in an emergency" is incredibly flawed. God forbid there is a shooting, kids should be listening to their teachers to be instructed to safety not distracted. And their phones should not make noise when they are hiding.

If the emergency is on the outside of school, parents still need to go through the main office to pull kids out of school, so contacting them is also unnecessary. These helicopter parents smh


In my state, to live in an excellent school district is very expensive. We've been trying to move but always get out-bid and out-priced. Mind you we earn well above median but unfortunately, we were not "born early enough." Many folks living in the districts have been there well before it was expensive and probably cannot afford their own home if they had to buy it again. Shit sucks.

How much have they profited from selling this vs how much the fine was? Fines these days appear as just a cost of doing business.

Years ago I've passed on Immich because it was "prone to breakage" and went with a directory organization and syncthing for syncing. I still see immich doesn't have a stable release which is a bummer, although people report it is quite stable. I'm glad I went with the organization method I did. I do a lot more pruning of photos and less hoarding. I actually am able to view photos without getting "burnt out".

Agency is a great observation. But also bring up these conversations with your direct management so they recognize the work you do. Employees with less responsibilities outside of work (no kids, no families, etc) might appear to be high-agency while in reality being less effective. When a senior eng with perceived "low-agency" suddenly takes a leave, those effects are felt way more than if a "high-agency" junior does. All's this to say, make your impact know with blunt discussions. Don't distract yourself with blog posts and dashboards solely to prove you have impact.

Having conversations with management is beneficial in other ways too. You might think effort A or task B is really important, but your management can feel differently. They have a wider view of the company and might think that project C is really critical.

That's good info to know. If you know, you can advocate for A and B, or shift focus to C.


Today I discovered that geothermal energy is a thing, cool! An immediate question that comes to mind is how much "energy potential" does the earth store and "how is it generated"? I'd imagine something about gravity or magnetic waves that move the iron* core and stuff. Anyone know some resources I can read more about this?

Assuming we can drill deep enough and harness it, the thermal energy in the earth's crust is essentially infinite.

People said "the Earth is too big, human activity can't change the climate". Now look at where we are.

I wonder, if we draw enough heat out... would the core cool enough to shrink? And if so, would the crust collapse to the new size?

Pure speculation of course, but did the first guy burning coal know the outcome?

Anyhow, I love geothermal, think you're right, but just got tweaked on the word "infinite".


Just some rough physics..

Q = m c ΔT

m = mass of the crust (roughly 10^22 kg)

C = specific heat of crust (roughly 1000 J/kg·K)

ΔT = 1 K

Q = 10^25 joules would be needed to lower the earths crust by 1 degree K

About 10,000 years worth of today’s human energy consumption


Following on to this, enough sunlight hits the Earth in 30 minutes to power humanity for a year. So geothermal wouldn’t need to provide all of today’s human energy consumption, just that last bit that renewables, existing nuclear, transmission, storage, and demand response can’t provide for today.

(1GW of solar PV is deployed every 15 hours globally as of this comment)


I wonder how much ΔT you need at the crust to meaningfully change Earth's magnetic field by altering convection patterns in the outer core. I don't know enough physics to attempt an answer.

The outer core is 2,890 KM (~ 1800 miles) below the earths crust, and has the mantle in the way. The crust itself is only 30KM thick. [https://phys.org/news/2017-02-journey-center-earth.html] The crust is basically a thin layer of slag on top of a giant ball of molten everything.

Even at million+ year timescales, I can’t see any way the temperature of the upper crust could matter to the core at all - even if the crust was at absolute zero.

Dirt insulates relatively well, and the amount of thermal mass present is mindboggling.


if you lived in the Earth’s core (~6000k) the surface (~300k) would be a rounding error above absolute zero anyway

> would be a rounding error above absolute zero anyway

Kind of joking: unless there are nonlinear effects near 300K? Fig 4 [1] seems to suggest that the thermal diffusivity of the mantle grows very fast as temperature declines past 300K... but the data stop at 200K.

Reason for initial comment: we could probably set up a spherical heat equation to guess how crust cooling would change heat conduction at the outer core. But I have absolutely no idea how to reason about changes in heat conduction affecting the convection dynamics that generate the field. I was silently hoping for one of the domain experts lurking this forum to see it and share wisdom. (But overall it was a silly question, I know).

[1] https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/200...


Calculating or simulating how earths magnetic field behaves or is generated is quite a complex task. So im doubtful we can usefully estimate it to such precision. It would be interesting though.

We know that if the convection in the outer core stops, the Earth's magnetic field stops, and removing enough heat from the core will stop the convection.

Yes but calculating the energy draw required for any measurable change in this effect is very different from knowing the rough process it operates on.

We know how weather works quite well, but knowing if it will rain in a week is an entirely different beast.


I've seen a confident estimate in the form of a calculation. They know what kind of compounds (term?) are in the outer core and they know the minimum temperature those compounds need to be at to be free-flowing enough to sustain the field. And I'm pretty sure we know the current temperature of the outer core.

My memory is that the calculation found that if humanity switched to geothermal for all its energy needs, then in only about 1000 years, the core cools enough for the magnetic field to stop, but I am not sure.

(We should definitely deploy geothermal in the Yellowstone caldera though long enough to cool it down enough so that it will not erupt again.)


That is definitely not true hahaha. The outer core is several thousand km down, and the crust is only 30km thick. And we have the entire mantle below us.

Humanity could max out geothermal for a million years and never make a dent.


Whoa, this is a bit scary. As mentioned earlier, it should basically be used in a way where other energy sources are tapped first, and only the shortfall is covered.

Isn't the atmosphere we're affecting on the order of 1 millionth of Earth's mass?

It'd take multiple orders of magnitude more impact from humanity for us to actually affect the core, no?


There is also the issue that using geothermal energy can cause earthquakes.

Here are some links I found related to this

Pro-geothermal position: https://www.caltech.edu/about/news/producing-clean-energy-ca...

Anti-geothermal position: https://news.stanford.edu/stories/2019/05/lessons-south-kore...

My conclusion: Geothermal makes research into plate tectonics and earthquake mitigation considerably more valuable, so we can figure out how to do it in a way that reduces earthquakes rather than creating them.


I think thats actually disputed. I'm not entirely sure though and i dont have the time to look it up right now.

Alot of the heat comes from radioactive decay. Heavy radioactive elements under alot of pressure and heat. There's also friction from our moon (earth seems to have a more active core than many other planets) and simply being very well isolated. (Rock is a terrible heat conductor)

Also... Iceland. They're massive in aluminium production for a reason. They have basically infinate abundant energy boiling out from the ground. Here in sweden its used by alot of homes for heating; getting a well producing 60c water is pretty cheap. (A single home may have their own well)

The issue is using it for power really only becomes viable when you reach superheated steam temperatures. And at those depths; drills melt, so its use outside of volcanic regions has been real slow.


>earth seems to have a more active core than many other planets

Fun fact: Plate tectonics has been proposed as an explanation for why complex life is here and not elsewhere.


Fascinating visualization. To think, we can visualize the entire* process but cannot understand the inner workings of a model with regards to decision making. This was true last I looked into it a year or so ago, not aware on any advancements in that aspect.

We completely understand the inner workings and can see the emerging result, but it's hard for us to accept that it took no decision and just chose a nice word to complete a sentence, time after time, and sounds intelligent. Then it says Strawberry has two r, and you're like ok, it's just a huge statistical matrix with zero value.

Hammers have zero value when you’re trying to cook food with them, too.

Hammers that sucked up half a trillion dollars from the economy and are basically propping it up, and the makers and everyone else around them are shouting from rooftops that they are great at cooking food.

And your boss's boss and his boss and the owner and the investors and every other rando is asking whether we are cooking with hammers yet and if not, why because how else can we get rid of those expensive cooks who use kitchenware.

And the expensive cooks _actually_ want to be fired!

"Guys, if this hammer works as advertised, you'll totally be fired"

"Ok, boss! Let me figure it out for you"



Well done. I really enjoy blog posts that dive into topics that probably cross the minds of most home lab-ers at one point or another.

Great analogy! Puts a succinct labele to my mental model around it Will definitely use this.

Though, with lossy media it is obvious when it is lossy. Yet LLMs will exhibit overconfidence to tell you facts that don't exist. Not suggesting LLMs exhibit human characteristics, just that there is yet a better analogy out there :)


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