Today I Learned

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fresh_42 said:
... and I still don't see what you mean. Could you enlighten me?
It's a sort of atom-y thing inside a speech bubble - so "talking science" or "talking about science".
 
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fresh_42 said:
I was looking for some message behind atoms with three valence electrons, or Lithium.
It's a good thing it wasn't a subtle message involving Uranium. :oldsmile:
 
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fresh_42 said:
By the way: What do we have about the Lithium puzzle? Do we have an insight?
But that's the classical model. Is our PF a classical forum?
 
mfb said:
Today I learned that ##\frac{\sqrt{x^2+1}-1}{x} = \frac{x}{\sqrt{x^2+1}+1}##. Looks funny, but it works.
Found when reducing rounding errors for small x.
Context
Back in high school while coding up a lunar landing game, I first encountered that issue and learned of the alternate quadratic formula: $$x=\frac{2c}{-b \pm \sqrt{b^2-4ac}}$$ which can evade the cancellation of near equal quantities and associated loss of precision.
 
Today I learned that new sofas come with a chemical smell that irritates my nose and throat, and my wife hates the smell too. We left the windows open for hours (it was quite windy but only just above freezing outside) but it doesn't seem to have helped very much. I find it hard to believe that customers are really expected to put up with such an unpleasant experience, and I wouldn't be surprised if it is actually harmful to health.
I'm sure our previous ones weren't anything like so bad. Perhaps it's something to do with the"fire resistant" foam and materials, which were much less extreme 15 years ago. (No-one I know is a smoker so I can't see any benefit at all in fire resistance now). Our previous sofa had washable covers and cushions, but our new one cannot be cleaned properly at all (neither washed nor dry cleaned) because of some fireproofing treatment.
We deliberately avoided buying the "stain-proofing" treatment and insurance, mainly because of the ridiculous price (which made a mockery of the sale price of the sofa itself), but I guess that might well have made an even worse smell.
 
fresh_42 said:
I'm not totally sure, but isn't there a massive lack of Lithium in the universe?
Humans are stealing it from the universe (for their cell phones and electric cars)
 
Today I learned that at my advanced age with all the sum knowledge and experience that we'll probably never understand the nature of a woman. Some things are just not meant to be understood: )
 
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zoki85 said:
Humans are stealing it from the universe (for their cell phones and electric cars)
Some are stealing it for psychotic purpose too.
 
Today I learned that I have become a PF electron. No idea what that metaphor means but I'm no longer a quark, haha!
 
Ibix said:
It's related to the points you get from trophies - I think estimated thresholds can be found on this thread (or at least in General Discussion) if you care to search.
What does electron signifies?
 
Just that the number of trophy points you have is above a certain value. You probably got an alert about a trophy, for replying or posting a certain number of times or whatever. Noting that you have 22 trophy points, I guess "electron" is 20+. As I say, someone reverse engineered it - search General Discussion for posts containing ocean and mountain.

Edit: it doesn't mean we think negatively of you... :wink:
 
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TIL... that some people now abbreviate Starbucks -> Sbux.

(Hence I also learned that laziness is a monotonically increasing function of time).
 
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Today I learned that it's Stupid Leap Day today! o0)

So I had made an appointment with the San Jose Household Hazardous Waste department for today to drop off some old motorcycle fluids and an old battery. I made the appointment online earlier this week, and thought I'd picked an 8AM Saturday dropoff appointment timeslot. I'd printed out the appointment and some other paperwork, and had it ready to go this morning.

But as I was putting the box of containers in the back of my vehicle to head down to the dropoff, I double-checked the appointment and saw 2/29/2020. But then I looked at my watch and saw 3/01, and I panicked. I started thinking, "How could I have been so stupid to make the appointment for Friday instead of Saturday? I wonder if they'll still let me do the dropoff today, or if I'll have to reschedule..."

So on the chance that they'd take pity on me and let me do the dropoff today instead of yesterday, I headed down the hill. When I got there right on time, I checked in with the guy at the gate, and was all apologetic saying that I think I messed up the appointment and it was for yesterday instead of today. He just asked for my name and checked me off the list for today (and I'm thinking WITW?), and waved me through to the dropoff spot.

I was happy that it went so smoothly (but still confused why I was on his printout list for today), and headed into work (yes it's Saturday). Now several hours later I notice online that today is Leap Day, and realized that my watch had automatically gone from 2/28 to 3/01. Lordy! o0)
 
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Today I re-learned from @berkeman that my watch does not understand leap days.
 
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Today, I learned that 70% isopropanol is preferable to 99% for the purposes of disinfection.
 
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Ibix said:
Just that the number of trophy points you have is above a certain value. You probably got an alert about a trophy, for replying or posting a certain number of times or whatever. Noting that you have 22 trophy points, I guess "electron" is 20+. As I say, someone reverse engineered it - search General Discussion for posts containing ocean and mountain.

Edit: it doesn't mean we think negatively of you... :wink:
Is there anything less than a PF quark?

I don't know if there is an astronomical term for a body that enters the solar system, maybe interacts slightly with one or two planets and then vanishes out beyond possibility of observation? (They might very slightly have altered some orbits and tides scarcely detectably, but overall there is only a small effect bringing forward the running down of the system.) :smile:
 
Today I learned that it’s important to check to make sure you click reply and not reply all to an email sent to dozens of people. Now I keep getting reply’s from people trying to reply to the first email and instead accidentally replying to mine.
 
Universe is full of giant clouds containing significant percentage of https://www.sciencealert.com/cosmic-cloud-contains-enough-alcohol-to-keep-the-world-world-drinking-for-a-billion-years.
Let's have a party!:biggrin:
 
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