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> Is “unagentic engineer” a euphemism for human/not-AI?

Pretty sure it means someone who plods along in life, going with the flow, working but with no self-conceived roadmap of ambition, low extroversion, low desire to make decisions, etc


Perhaps it be better to consider 3.5 years as a half-life instead.

Every 42 months, half your life has or could be upturned.

That’s how long it takes to find yourself in new job, or for a new child to become a fully talking toddler with a personality, or a long-term relationship to solidify, or a national government to turn over, or a pandemic to initialize and then resolve. That all tracks.


>The device can be used by industrial and medical radiation users, regulatory authorities, the nuclear energy industry, first responders and military users

It cannot be used by TSA employees. They are not allowed to even wear dosimeters.


TSA employees can use them, they are just not permitted to (for some reason).


Federal liability around future health concerns.

Edit: https://www.cdc.gov/niosh/hhe/reports/pdfs/2003-0206-3067.pd...


Those big backscatter X-ray machines [1] have a powerful X-Ray tube. Not that I'd be worried if I flew once a month, but if I was a member of the aircrew and going through more than once a day I'd be concerned. Think about when you get a medical or dental X-Ray and the operator puts on a lead apron and goes around a corner -- they don't get anywhere near the dose that you get, but they are around the machine all the time time. TSA staff did none of that.

Those machines were killed off because it was easy to demonstrate walking right through them and not getting detected if you wear a gun in a holster the way you would normally wear a gun if you weren't trying to hide it. The trouble is it depends on the gun being between you and the scanner because the gun appears black against the white radiation bouncing back from all the hydrogen atoms in you. With no background the gun is black-on-black and invisible. When people realized you could put a cop in front of the scanner and demo that the scanner couldn't see his gun it got around quickly that the scanner was worthless. [2]

[1] https://en.wikipedia.org/wiki/Backscatter_X-ray

[2] Ok, instead of getting scanned twice on your front and back they could scan you four times but this is getting ridiculous.


I'm not sure what is the context of your link. Is it supposed to show that TSA employees are not permitted to wear dosimeters? Because if so, I can't find that in there.


Why aren't they?


The earths rotation creates it. Or was this rhetorical.


No, it was a serious question. Does anything that rotates create a magnetic field even if it is not an electrical material?


In case of Earth, Wikipedia describes [1] it as being "[..] generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in Earth's outer core". This makes Earth a geodynamo [2]. (The aforementioned Wikipedia page is actually really long and detailed, a lot more than I would have thought)

[1] https://en.wikipedia.org/wiki/Earth%27s_magnetic_field [2] https://en.wikipedia.org/wiki/Dynamo_theory


The iron core but there are many open questions https://news.mit.edu/2020/origins-earth-magnetic-field-myste...


Basically: moving electric charge = magnetic field. It's equivalent, that's why it's called electromagnetism: it's one and the same force.

The Earth rotates, liquid iron (inside Earth) flows => a current flows in the iron => there is a magnetic field.


No, otherwise Mars would have a magnetic field just like Earth.


Doesn’t driving west to east on a highway slow down the Earth’s rotation, via the power transferred into the ground?


It's actually driving north south that changes the rotation speed. Because your 'real' speed gets higher as you get closer to the equator, you 'steal' momentum from the earth as you get closer to the equator.

Its effectively the same principle as a figure skater pulling in their arms when spinning, to spin faster.


Reminds me of a glorious question from undergraduate physics:

Calculate the change in the length of the Earth's day if the UK were to switch to vehicles driving on the right-hand side of the road rather than the left..


Is that due to all the roundabouts switching direction relative to the Coriolis effect? Hence the relevance of the UK?

Presumably without roundabouts it's all random directions and balanced?

Or am I barking up the wrong tree?


It was indeed all about the roundabouts. I forget the details but I do know it took us quite a while to get there(!)

Those tutorials filled me with dread at the time, but with hindsight they were - how can I put this - a fairly formative experience.

Watching your tutor use paper and pencil - and estimation - to calculate something like that was actually quite inspiring. That was, once it stopped being terrifying.


Yes, but that energy is returned when you break


Things get interesting when you reverse.


Then when you stop the angular momentum of your car is transferred back to the earth.


Only while you're driving.


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