Today I Learned

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"entangled"?

But what you are probably looking for is nonlinear optics or higher harmonic generation.
 
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mfb said:
"entangled"?

But what you are probably looking for is nonlinear optics or higher harmonic generation.
Maybe.
I did some more spectral experimenting(fail!), and glossed over nonlinear optics(way over my head), last night, and decided I had a laundry list of questions.
It may take me a week to gather my thoughts on this topic.
 
Hmmmmmm going back to 1960's high school physics
Particles can stick together and combine their mass
Waves can add and combine their amplitude

so i guess whichever you consider light to be, particle or wave, it's plausible two pieces of it could team up and excite something in a retina ?
 
jim hardy said:
Hmmmmmm going back to 1960's high school physics
Particles can stick together and combine their mass
Waves can add and combine their amplitude

so i guess whichever you consider light to be, particle or wave, it's plausible two pieces of it could team up and excite something in a retina ?
Those are two of my questions.
 
TIL that my sister, who does traveling displays for the Smithsonian Institute,
is working on a Star Wars display in Denver and is doing the "wiring for the Light Sabers!".
 
TIL of software called GEMS, a Microsoft Windows based election handling product
http://www.essvote.com/products/7/39/software/gems/
Global Election Management System
GEMS™ is a Microsoft Windows®-based election management and tabulation software. It allows election administrators to easily and completely control every step of the election process, from ballot layout to election reporting, all in one proven application.

GEMS automates the complete election cycle from precinct/dist
completely control ? Surely that's a mal-mot.

TIL also it tallies votes in floating point not integer. I suppose that makes sense because the numbers are so large plus it's easier for programmers to just hand numbers to a floating point processor than to do integer arithmetic on such large numbers. 300 million takes 29 or 30 bits? While floating point will result in fractional votes the errors should be very small.

But that the GEMS system is so amenable to this kind of skulduggery is disconcerting.


that video is linked from here
http://blackboxvoting.org/
headquartered near Seattle
who claim to be nonpartisan
but i don't really know for sure who they are.

see my signature
old jim
 
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fresh_42 said:
Sure? ...

Sorry about the long video, fresh. I hope you find time to watch it.

It caught my interest because Shelby County Tenn and Dade County Fla(where i grew up) were among first to implement something called Metropolitan County Government in mid 1950's.
Color me suspicious, but the characters who pushed it in Miami had not long prior got out of Greene County Missouri(my ancestral home) just ahead of the tar and feathers.
Probably that's why i m attracted to conspiracy theories . I have to watch myself.

old jim
 
jim hardy said:
TIL of software called GEMS, a Microsoft election handling product
http://www.essvote.com/products/7/39/software/gems/

completely control ? Surely that's a mal-mot.

TIL also it tallies votes in floating point not integer. I suppose that makes sense because the numbers are so large plus it's easier for programmers to just hand numbers to a floating point processor than to do integer arithmetic on such large numbers. 300 million takes 29 or 30 bits? While floating point will result in fractional votes the errors should be very small.

But that the GEMS system is so amenable to this kind of skulduggery is disconcerting.


that video is linked from here
http://blackboxvoting.org/
headquartered near Seattle
who claim to be nonpartisan
but i don't really know for sure who they are.

see my signature
old jim

MS Windows software has full control and enough reliability for this kind of project ? :-D
 
jim hardy said:
Color me suspicious, but the characters who pushed it in Miami had not long prior got out of Greene County Missouri(my ancestral home) just ahead of the tar and feathers.
Lol. Funny picture. I remember to have answered a post on FB calling Trump's accusation of a rigged election ridiculous. But on the other hand, there has been Florida, there has been the DNC and its treatment of Bernie ...

Your post just reminded me of that.
 
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jim hardy said:
TIL of software called GEMS, a Microsoft election handling product

Except Microsoft had nothing to do with this project.

BoB
 
rbelli1 said:
Except Microsoft had nothing to do with this project.

okay , i misinterpreted their phrase "GEMS™ is a Microsoft Windows®-based" , sorry about that.
Doesn't allay my unease any, though.
 
jim hardy said:
okay , i misinterpreted their phrase "GEMS™ is a Microsoft Windows®-based" , sorry about that.
Doesn't allay my unease any, though.
Yep, guess this is the price of modern times. I never have heard about hacked punched cards. :cool:
 
jim hardy said:
might explain some of the insane conspiracy stuff out there ?

Money making schemes with little or no political agenda. "Never give a sucker an even break."
 
OmCheeto said:
I think that belongs in the "weird news" thread. :-p
Today I realized that I haven't seen any non-weird news for a while.
 
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Today I learned about antiprotonic helium. If antiprotons are mixed with helium, some of them replace electrons to form antiprotonic helium atoms, which last long enough (tens of microseconds) to allow some measurements. This doesn't work for any other element.
 
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Jonathan Scott said:
Today I learned about antiprotonic helium. If antiprotons are mixed with helium, some of them replace electrons to form antiprotonic helium atoms, which last long enough (tens of microseconds) to allow some measurements. This doesn't work for any other element.

So Jonathan, these antiprotonic helium atoms would therefore have an extra proton's worth of mass?
 
BillTre said:
So Jonathan, these antiprotonic helium atoms would therefore have an extra proton's worth of mass?
Yes, give or take an electron of course.
 
It also works for hydrogen -> protonium

Are you sure it doesn't work for other elements? I would expect the lifetime to go down, so experimental observation is more challenging, and also the analysis gets more complicated. Maybe no one did it so far because it is not very attractive.
 
According to the antiprotonic helium wiki,

"The antiproton can thus orbit the nucleus for tens of microseconds, before finally falling to its surface and annihilating. This long lifetime is seen only in the case of antiprotons mixed in helium; in all other substances, antiprotons annihilate a million times faster, in less than a picosecond."​
 
mfb said:
Well, that is wrong, removed it. Positronium for 1.1µs (page 9) - and higher l would lead to longer lifetimes.
You mean Protonium, I presume (combination of antiproton and proton), although that isn't really like an element, and it also appears that Protonium is only stable in isolation, not as a gas like antiprotonic helium. Also, it is not created by just mixing antiprotons into hydrogen; it requires a magnetic trap to mix antiprotons and protons.

I don't see any problem with the original specific statement: "This long lifetime is seen only in the case of antiprotons mixed in helium; in all other substances, antiprotons annihilate a million times faster, in less than a picosecond."
 
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Jonathan Scott said:
I don't see any problem with the original specific statement
That's what I thought. But Positronium is interesting, too. And with 142 ns is Orthopositronium almost a Methuselah.
 

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