Today I Learned

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Today I learned that cleaning a white hat can be done with bleach cleaner, but it’s important to rinse it before wearing it again. I also discovered that "oyster veneering," a woodworking technique from the late 1600s, is experiencing a minor revival despite its labor-intensive nature. Additionally, I learned that the factorial of 23 (23!) equals 25,852,016,738,884,976,640,000, which interestingly has 23 digits, a unique coincidence among factorials. I found out that medical specialists often spend less than 10 minutes with patients, and that watching TV can contribute to weight gain. Other insights included the fact that a kiss can transfer around 80 million microbes, and that bureaucracy can sometimes hinder employment opportunities. The discussion also touched on various trivia, such as the emotional sensitivity of barn owls and the complexities of gravitational lensing around black holes.
  • #1,801
Cosmic rays are quite rare compared to terrestrial radiation, and it is unclear if life can form if there is just this energy source. They are still water-based, and every place with liquid water is considered as place for life already.
 
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  • #1,802
BillTre said:
TIL that there are microbes in a South African gold mine can feed off of the effects of radiation on the chemicals around them.
This implies similar organisms could feed off of cosmic rays and could result in expanding the environments where life might be found.
My first thought has been: Wow, wouldn't that be useful for our nuclear waste problem?
 
  • #1,803
How? They just use ions as energy source. That doesn't influence the chemical composition or activity of the material in any way.
 
  • #1,804
Sure, but maybe enough of them could reduce heat and necessary shielding, in the sense of shortening the range of radiation.
 
  • #1,805
They don't violate energy conservation either. The chemical energy they produce is absolutely negligible compared to the overall heat production. And they do not reduce the radiation length. They increase it compared to heavier elements.
 
  • #1,807
Buzz Bloom said:
TIL (actually yesterday) that Stephen Hawking is hawking jaguars.
I heard that the other day, too.

I love Stephen's excuse, as, it sounds so, um, human:

“You all know me as Professor Stephen Hawking, the physicist wrestling with the great concepts of time and space. But there is another side to me that you may not know: Stephen Hawking the actor. I have always wanted to be in a movie playing the part of a typical British villain. And now, thanks to Jaguar my wish has come true.” -Stephen Hawking
​

Thank you, professor Hawking.

Many of us, are on the other side of the bridge, wanting to be, as brilliant as you.
 
  • #1,808
I have a lifetime gym membership for a fitness center 600 miles away in another state that I haven't been to in years. Every once in a while I check to see if they have expanded to where I live now. TIL that they went out of business two years ago. :wideeyed:
 
  • #1,809
Borg said:
lifetime gym membership
For the lifetime of the gym.
 
  • #1,810
Borg said:
I have a lifetime gym membership for a fitness center 600 miles away in another state that I haven't been to in years. Every once in a while I check to see if they have expanded to where I live now. TIL that they went out of business two years ago. :wideeyed:
Lucky you, that you hadn't

to find out!
 
  • #1,811
Today I learned the reason patients should take their Coumadin dose in the evening. Makes sense when it was explained.
 
  • #1,812
Re-reading my General Physics book...

I re-learned a useful tip: to keep one hand on my pockets (if I have) when another touches electricity. To avoid electricity from using my body to make ground. It's a little mini section on the book talking about electric hazards. The book is: https://www.amazon.com/dp/0131992260/?tag=pfamazon01-20

Chapter 26.
 
  • #1,813
Psinter said:
keep one hand on my pockets (if I have) when another touches electricity. To avoid electricity from using my body to make ground. It's a little mini section on the book talking about electric hazards.

Sounds like a practical physics book.

Old timey electricians 'feel' first by brushing with the back of their hand or fingers not the front . That's because electric current makes your muscles contract.
If you contact with the back of your hand that'll pull your hand and fingers away from the source. Don't ever touch it so that contracting muscles would wrap your fingers around it for you won't be able to let go.

It's counter-intuitive. We usually feel with our fingertips , but when 'back of the hand' was explained to me by an old lineman it made so much sense i quickly formed the habit.

Maybe that's in your book too.

Anyhow - thanks for sharing. Awareness of details like that saves lives .

old jim
 
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  • #1,814
mcknia07 said:
Today I learned the reason patients should take their Coumadin dose in the evening. Makes sense when it was explained.
Why should they?
 
  • #1,815
Today I learned that the Chicago Cubs were not the first occupants of Wrigley Field. That distinction goes to the Chicago Whales.

(Whales? in Chicago? o0))
 
  • #1,816
jtbell said:
Today I learned that the Chicago Cubs were not the first occupants of Wrigley Field. That distinction goes to the Chicago Whales.

(Whales? in Chicago? o0))
You're not the first who asked:
http://www.lansingstatejournal.com/story/travel/2016/03/31/heres-whopper-whale-watching-lake-michigan/82473438/
 
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  • #1,817
aa said:
Why should they?

It's so that if a doctor has to adjust their dose after blood work they can get the correct dose in that same day. Plus, if you take the dose in the morning it will change the INR levels and not reflect a true accuracy of the levels in the blood.
 
  • #1,818
Today I learned (following up something I read online) that my phone camera sees a bit of infrared. In particular, it sees the output from my TV remote control as a purple glow even though I can't see it directly. Apparently the sensors are sensitive to infrared but the camera has a thin filter which is supposed to cut most of it out.
 
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  • #1,819
Jonathan Scott said:
Today I learned (following up something I read online) that my phone camera sees a bit of infrared. In particular, it sees the output from my TV remote control as a purple glow even though I can't see it directly. Apparently the sensors are sensitive to infrared but the camera has a thin filter which is supposed to cut most of it out.
I knew that but had never done a demo. That's pretty neat...
 
  • #1,820
That's a handy way to check whether a remote is working.
 
  • #1,821
Jonathan Scott said:
Today I learned (following up something I read online) that my phone camera sees a bit of infrared. In particular, it sees the output from my TV remote control as a purple glow even though I can't see it directly. Apparently the sensors are sensitive to infrared but the camera has a thin filter which is supposed to cut most of it out.
Today I verified that I can see infrared light at 872 nm +/- 40 nm.
I have an underwater camera that I bought 10 years ago, and it has a 12 infrared led illuminator. The camera is sensitive to both visible and infrared light.
I always assumed that the lamps had a broad spectrum, as I could clearly see the light, but today I found out that they don't, with the use of diffraction grating.

There was some argument in a thread several years ago about this: Can you see IR? [2006-2008]
There was much chatter about people who could see such light being mutants, but, it looks as though it's not quite the case.
After much googling, I finally found someone who had done the experiment, and had a reasonable explanation how it works:

The human eye can see 'invisible' infrared light [phys.org Dec 2014]
"The visible spectrum includes waves of light that are 400-720 nanometers long," explained Kefalov, an associate professor of ophthalmology and visual sciences. "But if a pigment molecule in the retina is hit in rapid succession by a pair of photons that are 1,000 nanometers long, those light particles will deliver the same amount of energy as a single hit from a 500-nanometer photon, which is well within the visible spectrum. That's how we are able to see it."​

ps. I used a mercury vapor lamp as reference, as usual. [image]
8 second exposure time.
 
  • #1,822
OmCheeto said:
After much googling, I finally found someone who had done the experiment, and had a reasonable explanation how it works:

The human eye can see 'invisible' infrared light [phys.org Dec 2014]
"The visible spectrum includes waves of light that are 400-720 nanometers long," explained Kefalov, an associate professor of ophthalmology and visual sciences. "But if a pigment molecule in the retina is hit in rapid succession by a pair of photons that are 1,000 nanometers long, those light particles will deliver the same amount of energy as a single hit from a 500-nanometer photon, which is well within the visible spectrum. That's how we are able to see it."
Very interesting. Presumably this ability to render IR light as visible is not restricted to human retinas? So it might explain why it is that animals in the wild seem to stare towards the 'invisible' IR floodlight of a hidden wildlife IR camera and can be seen to approach warily the fringe of the invisibly floodlight circle of ground.
 
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  • #1,823
Today I learned that among Donald Trump's other abilities, he has the power to add floors to an existing building.

http://www.nytimes.com/2016/11/02/nyregion/donald-trump-tower-heights.html

Or take the https://www.trumpinternationalrealty.com/property-gallery/trump-international-hotel-and-tower-new-york, the hotel and residential building on Columbus Circle that was, pre-Trump, the 44-story Gulf & Western office building. Mr. Trump improved the structure so thoroughly that it managed to stretch into a 52-story tower, even though it stayed, strictly speaking, the same height.
 
  • #1,824
Not sure what to think about this.

I used to work in a lab where we used IR of various wavelengths to illuminate biological specimens in microscopes.
The IR penetrated tissue better (deeper into a sample that is) and activated particular fluorescent dyes.

We also had two-photon confocal microscopes that used IR. I was always told that the two photon microscopes required an extremely high photon density to get two photon excitation (the two photons had to be in the same place at the same time (within some small but vague limits)). This was achieved by using pulsed lasers which concentrated the photons into a very small fraction of the overall time and focused the laser beam into a very small dot.

This makes me doubtful that a TV remote could could achieve two photon illumination very efficiently.

On the other hand, some animals can detect a wider ranges of frequencies than humans.
Pit vipers (like rattle snakes) have a unique structure that can detect IR. They don't use their eyes for this, but have sensors in pits that form a very crude pinhole camera. Information from these sensors does get mapped in the optic tectum, a midbrain sub-cortical sensory center where the optic field is laid out in 2D, but with poor resolution.
 
  • #1,825
NascentOxygen said:
Very interesting. Presumably this ability to render IR light as visible is not restricted to human retinas? So it might explain why it is that animals in the wild seem to stare towards the 'invisible' IR floodlight of a hidden wildlife IR camera and can be seen to approach warily the fringe of the invisibly floodlight circle of ground.
One problem with my experiment, and the scientist's experiment, is that something is not quite right.

"The research was initiated after scientists on the research team reported seeing occasional flashes of green light while working with an infrared laser."​

Both my camera and I, see red light. So something is not quite right.
Of course, this being the "Today I learned", I was forced to publish my findings too early, as there is no "Over the last week, my experiments have taught me" thread. :biggrin:

I may have to start a new thread. :angel:
 
  • #1,826
BillTre said:
I used to work in a lab where we used IR of various wavelengths to illuminate biological specimens in microscopes.
The IR penetrated tissue better (deeper into a sample that is) and activated particular fluorescent dyes.

Today I learned of IR fluorescence.
For some reason, I was only aware of UV fluorescence.
I am definitely going to have to start a new thread.
 
  • #1,827
OmCheeto said:
The human eye can see 'invisible' infrared light [phys.org Dec 2014]

That's really cool.
The research was initiated after scientists on the research team reported seeing occasional flashes of green light while working with an infrared laser. Unlike the laser pointers used in lecture halls or as toys, the powerful infrared laser the scientists worked with emits light waves thought to be invisible to the human eye.

Green, light from infrared !

visible_light_spectrum.jpg


One wonders what else might trigger those photoreceptors.
 
  • #1,828
A common way to "see" near infrared lasers in a lab are materials that absorb two photons and emit one photon at higher energy. That can be green, but it can also be at longer wavelengths (the remaining energy is then lost elsewhere).
 
  • #1,829
jim hardy said:
That's really cool.Green, light from infrared !

View attachment 108366

One wonders what else might trigger those photoreceptors.
Their whole study goes against everything I know about quantum physics.
Which is very close to zero, btw.
Ergo, my crackpot mind suspects: "commingled wave-functions?" :biggrin:

----------------
please don't ban me. please don't ban me. :(
 
  • #1,830
TIL that I coined a new term, as Google claims that there are; "No results found for "commingled wave functions"."

I find that odd.

But then again, I'm pretty sure those quantum mechanics probably have a much fancier term.
 
  • #1,831
"entangled"?

But what you are probably looking for is nonlinear optics or higher harmonic generation.
 
  • #1,832
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.
 
  • #1,833
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 ?
 
  • #1,834
  • #1,835
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.
 
  • #1,836
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!".
 
  • #1,837
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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  • #1,838
jim hardy said:
completely control ? Surely that's a mal-mot.
Sure? ...
 
  • #1,839
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
 
  • #1,840
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
 
  • #1,841
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.
 
  • #1,842
  • #1,844
jim hardy said:
TIL of software called GEMS, a Microsoft election handling product

Except Microsoft had nothing to do with this project.

BoB
 
  • #1,845
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.
 
  • #1,847
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:
 
  • #1,848
Many countries still use paper for a good reason.
 
  • #1,849
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."
 
  • #1,850
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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