Shattered Backboard Glass and the Cat's Eye

"Dad, the basketball backboard is broken."

My 8-year-old son was looking out the back window. I was talking to a friend in our family room, and basketball was the last thing I was thinking about.

"No it's not," I thought as I stood up to investigate. This was August 2019. The backboard was only 2 years old. And that glass is 1/2-inch thick tempered-glass — and crazy heavy! The basketball stand was a splurge purchase when we bought the house in 2017 — over $2000 for a heavy-duty stand with a dunk-ready hoop (since I do so much dunking! haha) plus a net, and light. It's beautiful, really — kind-of a centerpiece in our back yard.

But at that price and age, there's no way it could be broken. Nobody had even been out there playing.

But I was wrong.

Wow, not just a little broken — shattered.

We immediately noticed that the break seemed to radiate out from a single point:

Another view:

Looks like something must've hit it.

(But what?)

---

I emailed the company. They were sympathetic, but they said it was clear that something had struck it, and the warranty didn't apply. They offered a replacement at a small discount.

Something was bothering the engineer in me, though.

I had looked around under the hoop for a rock or some other kind of projectile, and I hadn't found anything.

If the backboard had been struck by something small, like a bullet or a bb or a rock or something, I expected it would have shattered the impact site to powder, even if at a very small point. There was nothing like that.

If it had been struck by something large — a bird? hard throw with a basketball? a softball? — then I would've expected to find some marks on the surface of the glass, or the item itself. There was nothing.

I couldn't let it go.

---

A few Google searches, nothing useful.

I wrote a pretty long and piqued email to the company, trying to lay out the possible causes and how likely how unlikely it was that it had been struck based on the evidence, and how terrible an experience it would end up being if I had to replace it under those conditions...

But I didn't send that email. It just didn't sit right.

So I went back to Google.

This time, I found something — Nickel Sulfide in Tempered Glass Causes Spontaneous Fracture, by Thomas L. Pane, PE. Ah ha! Mr. Pane describes a case study of my *exact* situation, a pane of tempered glass shatters for no apparent reason.

Here's a comparison of the images, one from his site, and one from my backboard. Notice the distinctive "cat's eyes" pattern at the center of the fracture, two adjacent 6-sided shards.

A closer look shows the defect:

Turns out, it's a known issue in tempered glass manufacturing.* It's rare, and very hard to prevent or detect. Nickel sulfide is uniquely similar to water in that it's more dense when it is very hot, but as it cools, it wants to convert to a crystal form that is larger/less-dense. A tiny fleck of nickel sulfide in the glass is all it takes.

Tempered glass uses alternating layers of tension and compression to create huge internal pressures which makes the glass very strong. When the glass is first created the nickel sulfide has a hard time forming a crystal due to the high temperatures, and as the glass cools the nickel sulfide can't crystallize due to the high pressures. But once the glass is out in the sun, it can heat up enough to sometimes allow a corner of the nickel sulfide to crystallize. More hot/cold cycles allow the crystal to grow, until the internal pressures on the surrounding glass from the crystal are too high and the glass shatters.

Wow. That was awesome — such a thrill to have such a compelling explanation with hard evidence!

Armed with this info, I went back to the company and they offered to replace the backboard for free if I paid for shipping, which I agreed to, though a little reluctantly since shipping was over $100. Also, the backboard they sent was probably one that failed quality control, it had some discoloration on the lines, so I wasn't thrilled about that either. But I was happy to have my hoop back up and working.

I've kept the cat's eyes on my desk as a reminder of the experience:

Since then, I bought a digital microscope, and took a few pictures of the impurity:

Here's the top piece, zoomed to 1000x:

Here's the bottom piece at 40x:

And the bottom piece at 1000x:

It's interesting that both halves of the cat's eyes ended up with parts of the crystal.

Hope that helps someone out there.

---

* See also The Achille Heel of a Wonderful Material: Toughened Glass, an nice dive into the science, sources of nickel in the manufacturing process, etc.

Ebola and skin

Two quick things I learned this week:

1. Here's a good overview from the CDC on how Ebola is spread. Note the caveat that "droplets of respiratory secretions [from coughs/sneezes] ... could be infectious".
2. Lotions and other skin-care products break down the natural protective layer of keratin in your skin so they can penetrate. But then if you handle slightly toxic substances (like BPA on thermal receipts from stores) those substances end up in your blood. (Yikes! via Science Friday)

So, lotions allow things on your skin to penetrate into your blood -- like maybe droplets from sneezes, etc.?

I'm not sure either of these points give us the whole story here, but I do plan on being more cautious with lotions.

---

And what about hand sanitizers? I suspect the problem is suspending the alcohol in a lotion... I wonder if we shouldn't just use straight rubbing alcohol for cleaning hands? Like an alcohol dispenser at the sink by the soap?

Food supplements

Science Friday from July:

"The best advice I can give to anyone is to just stop taking supplements."

Global health database

Imagine President Obama standing up and announcing a partnership with Google to build the most comprehensive anonymous health database the world has ever seen.

Google would be permitted to put ads in a small box off to the right.

Everyone in the world would be encouraged to create an anonymous account (or they could use their existing Google account if they trust Google), and input all of their health information -- i.e. diseases, medications, conditions, symptoms, diet, exposure, activities, cities lived in, etc.

Why would anyone do this?

Individuals could be completely anonymous in their inputs. It could be touted as patriotic, and scientists and doctors would encourage everyone to put in their inputs. The system would offer health recommendations and potential risks based on their inputs. They could see whether they have shots due, or if their yearly colds happen to line up with allergy season. Or if their particular symptoms have a new treatment, e.g. stomach ulcers can be cured with antibiotics now.

Google would love it, they make money any time ads are shown, and they could target the ads to your conditions. They'd get access to a massive database of coincident health conditions and could use that to improve ad targeting to others.

The gov't, hospitals, medical universities, and even regular individuals could go in and do searches and download data, such as "What percent of folks with arthritis also have strokes"? or "In what cities are cold sores most common?"

Reputable organizations could request more information from folks with a given condition, e.g. "Have you ever lived near high voltage power lines?" sent to to all folks who get migraines. Users who wish to help the medical community by answering these kinds of questions would only have to click the "Help with research" link to see/answer them.

No one's name nor address is never entered, or even requested. Fraud would be rare since there'd be no motivation for it, and it would quickly get washed out in the volumes of data. Google could investigate or weed out obviously false info.

I could see something like this changing the world.

Spreading "culture"?

Remember my post on culture?

Looks like the "stool donor" approach is getting some traction -- Dr. Gordon is Director of the Center for Genome Sciences at Washington University in St. Louis, talking to Terry Gross on Fresh Air a couple weeks back about doing exactly that:

Dr. GORDON: Well, in this particular case, a fecal community was transplanted into a diseased individual's gut and there was a beneficial effect observed over time, reflected in improvement of their symptoms. ...

GROSS: I guess one of the things I find so interesting about this fecal transplant is one, its a fecal transplant. It's so odd to think of using in this case, a spouse's feces or the community of microorganisms in those feces to transplant into the ill person's gut. Its a way of transplanting good guy bacteria instead of using antibiotics to just kill the bad guy bacteria and in the process, kill the good guy bacteria too.

I still think someday it will be more common for doctors to administer bacteria cultures than anti-biotics.

Also interesting from this interview is that 90 percent of the cells we carry around aren't actually human -- but bacterial and other non-human microbes. By count, we're ~10x more bacterial than human. Surprising, hard to believe, but also very interesting.

Having politicians kiss your babies? Maybe a good way to get healthy/successful peoples' bacteria on your kids.

Colors in light

Pretty good explanation of how colors in light mix, and how some aren't "real", only perceived.

I'd seen this image before, but now I finally understand it!

Truth prevails, but when?

Max Planck, via wikiquote:

A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

"You need only believe the truth."

Henry Eyring Sr.:

The significant thing about a scientist is this: he simply expects the truth to prevail because it is the truth. ...

A young man [once] asked [me], "In high school we are taught such things as pre-Adamic men, but we hear another thing in Church. What should I do about it?" I think I gave the right answer. I said, "In this Church you only have to believe the truth. Find out what the truth is!" ... This Church is not worried about that question or other similar questions, because the Church is committed only to the truth. ...

Fortunately there is a way to find the *real* truth, John 16:13, though often it takes more time than I'd like.

Some have asked me, "Is there any conflict between science and religion?" There is no conflict in the mind of God, but often there is conflict in the minds of men. Through the eternities, we are going to get closer and closer to understanding the mind of God; then the conflicts will disappear.

I also noticed this quote, which sounds a lot like my "justified skepticism" entry from earlier.*

Finally, perhaps a believer never does more disservice to religion than to support the truth with bad arguments. The listener spots the obvious errors, becomes impatient, often "throws out the baby with the bath," and turns away, even from true religion.

The world is so full of "legacy" bad arguments I'm surprised there are still people who convert to the gospel these days.

---

* I find it fascinating how often I think I have original creative ideas, but really they're just me recalling something I read a long time ago and thinking it was my own. Hence I don't get to be very critical of Bill Swanson, whose book ended up doing the same thing.

Insights from Mike Myers and Hugh Sampson

Fascinating pair of interviews in the June 18th broadcast of NPR's Fresh Air with Terry Gross, where she spoke with Mike Myers (voice of Shrek, among other things) and Dr. Hugh Sampson, President of the American Academy of Allergy, Asthma & Immunology. (Here's a direct link to the audio file)

Too busy to listen to it? Here are the highlights:

Mike Myers

...on the sexual revolution of the 60s and 70s

MM: "The sexual revolution didn't end because of a sexual counterrevolution, I don't think the right had anything to do with it -- the moral right, or whatever you want to call them. I think what happens is that, that kind of swinging is an unsustainable lifestyle -- I think when people... cheat, it hurts their feelings. You know what I mean?"

TG: "Mmm hmm. Yes."

MM: "You know what I'm saying."

TG: (knowingly) "Yes."

MM: "I think that kind of stuff hurts, there's a hangover, there's an aftertaste, there's a price to be paid. So true love triumphs over lust."

(He then adds "that's the message of Austin Powers", which I find odd, but I never saw the movie so what do I know...)

I guess I just didn't expect anyone in Hollywood to believe that.

Dr. Hugh Sampson

... on the rise of food allergies in this country

You really need to listen to this one. Since I'm not a doctor, I can't even really speak intelligently to medical issues like these. Dr. Sampson is the President of the American Academy of Allergy, Asthma & Immunology, and his interview starts at 28:55 into the program.

Still here? Okay fine, I'll give you my summary of what he said:

• After years of having physicians advise people to delay feeding peanuts and other potentially allergenic foods to kids, we'd expect the number of people suffering from food allergies in the developed world to start dropping -- but it hasn't, it's rising!


• So now it appears that food allergies are *not* all genetic -- *we're* doing this!


• Some scientists believe we're misprogramming our immune systems. One theory, called "hygene hypothesis", postulates that the immune system gets programmed by bacteria that gets on our skin and into our gastrointestinal tract shortly after birth. If that's true, now that we've gotten so effective at eliminating bacteria from everything, we've killed off the bacteria that would otherwise "program" our systems with which things to be sensitive to -- and which not. [This topic sounds very familiar... - B]


• Peanut allergy rates in Canada, UK, US, Australia are high -- China, on the other hand, reportedly eats roughly the same amount of peanuts but has almost no peanut allergies; researchers think this may be due to the above, or possible the way we prepare our peanuts (dry-roasted, causing a "mallard reaction", instead of boiled).


• Another example, peanut allergy rates of children in Israel are 1/10 that of children in Hebrew school in London -- possibly due to a food used for weaning children called "bamba", which contains peanuts.


• Some experts are thinking that we may need to expose kids to peanuts very early or through the mother instead of the previous recommendation that we delay introduction. Dr. Sampson now recommends that physicians tell mothers that they don't have enough data to support making a recommendation on how/when to introduce food types to very young children -- and that the mothers should do what they feel is right, and (wisely so) to not feel guilty about the outcome.


• What are the 8 food products most responsible for food allergies? milk, egg, wheat, soy, peanut, various tree nuts, fish, shellfish


• How much of a peanut can cause an allergic reaction in someone with the allergy? They're not sure, so they err on the safe side and often over-label products, excluding lots more food items from the diets of people with those allergies.


• Another thing they're looking into is "delayed maturation" of the fructase enzyme in some children; apparently lactase breaks down milk products, and fructase breaks down sugars in fruits and vegetables. If a child has this condition, they'll get severe cramping and diarrea when eating certain fruits and veggies.

Part of me thinks the end result will be that expectant mothers will be told to follow the Word of Wisdom and just live normally otherwise. I'm stunned how often doing what's natural to children seems to end up being a generally healthy practice for them (e.g. eating dirt, not washing hands, etc.).

Also, I really enjoyed listening to this doctor because he explained why he believes what he does, and gave me a sense of how firm those beliefs are, and which ones are "softer". It bothers me that often our doctors take these "maybe"/"sometimes"/"looks like" findings, many of which are conflicting, and turn them into "thou shalts" and "thou shalt nots" -- but which often end up wrong!

Getting some real culture

Part One

Cindy (name changed) was in the same group as I when I first started as an engineering intern at my job -- I didn't interact with her much, but I remember she was a little overweight in physique and somewhat reclusive in personality. We soon went our ways and I only saw her in passing sometimes.

A couple years later I noticed that she was *much* thinner than the previous time I had seen her, "anorexia" being the only word I could think of. She also was walking waving her arms around in the air, almost like she was swimming or dancing or something, but the look on her face was one of determination, not of someone having fun. I wondered if she'd gone a little crazy.

Some time later, she approached me in the hall and asked if she might speak to me some day at lunch -- "privately".

"What's it about?" I asked, all kinds of red flags and bells going off in my head.

"I need help, and was hoping you might be able to help me -- but I'd prefer to discuss it in private." The red flags and bells hesitated... what could she mean? She barely knows me, what could she possibly think I could help her with? I feared it had something to do with children, though she was probably at least 20 years my senior.

I agreed hesitantly.

I immediately called my wife and my superiors, asking advice and letting them know where and when we were to meet, and all the circumstances I knew of. If she was going to proposition me with something, they would all find out almost as fast as I did, which I figured was my best protection from my biggest worry: people getting the wrong idea.

The day arrived, and she laid out an interesting story that has stuck with me ever since:

"I have a rare condition -- one that results in my gastrointestinal system being very delicate, susceptible to all kinds of infections. My doctors believe that it's because I have taken so many antibiotics that I've killed off all the 'beneficial' bacteria in my system that prevent the malignant kinds of bacteria from taking hold.

"That's where you come in. The doctors have suggested that if I can find a person to regularly donate stools for some time, they could be converted into a solution that could be transferred via enema into my system, and repopulate me with the healthy bacteria that I need."

I was stunned. She wants what from me?

We quickly decided that I wasn't a good candidate because I had gastrointestinal parasites on my mission in Ecuador. Granted I was pretty sure they were all gone now, but she didn't want to take any chances, and I was happy to not have to be in the stool-supply business.

Part Two

Fast forward to last Wednesday, to a routine doctors visit -- my first in ~15 years. I had woken up with a slightly sore throat, but figured I might be coming down with a cold. The doctor looked in my throat -- "How are you feeling today?"

"Woke up with a little bit of a sore throat."

"Well, it looks like you have strep."

Wha? Wow. Well, turns out I didn't, but a swabbing revealed that it was indeed a bacterial infection, and 20 minutes later I started a week-long antibiotics treatment.

Connecting the two

Now stick those two stories together.

1) Do I want to be wholesale-killing bacteria in my system, especially when I've got lots of good bacteria keeping me from other sicknesses? What choice do I have, I hate sore throats.

2) Where am I going to get more good bacteria after I kill off what I've got? Maybe that's what kissing is for. Keep passing the good stuff back and forth with your wife and kids. Maybe that's why our instincts are to kiss babies, to get your kids started off with the best cultures your gene pool has managed to come up with.

3) And lastly, if I'd had the right kinds of bacteria in my throat 3 days earlier, maybe I wouldn't have gotten the infection in my throat to begin with???

I wonder if there's someone out there who never gets bacterial infections in their throat because they *already have* the right kind of bacteria in there, keeping the bad stuff from getting a foothold.

So, if you have kids but you never get sore throats, can my kids kiss your kids? =)

"Global warming", "green", and me.

Somehow "green" is the new thing these days, all the companies want to be more green. (Here's the site that got me started on this...) A noble cause, who doesn't like greenery?

The Pacific Ocean has a garbage patch twice the size of Texas, China and Russia are a pollution mess, and we're pulling up every hydrocarbon we can find, representing (supposedly) millions of years of the sun's energy, and burning it as fast as we can.* This doesn't sound like we're being very good stewards of our planet.

However

... I always get nervous when environmentalist causes -- which seem to appeal disproportionately to the otherwise imbalanced folks out there -- line up with corporate initiatives.

Corporate America loves to find, or create, new "needs" that they can fill. Being "green" means that we need sensors to turn on and off lights when people come and go, better insulation in buildings, and energy-efficient computers. Hmm, sounds like a lot of things we need to buy -- check out all the business ads on this page.

In fact, on 3/23/08, Fake Steve Jobs (a famous not-Steve-Jobs blogger who has a remarkable perspective on CEO life) wrote a tremendous (though rather profane) article on this very point (quoted and cleaned up for my audience):

Truth is, Goldilocks does not really believe the world is about to burst into flames. What he does believe is that the global warming "crisis" is the next big way to make money off hype and fear. It's the Y2K scam all over again. Truth is, .... a bunch of lucky rich [guys are] scheming to get even more rich. I'm telling you this because I've talked to these guys. I've been invited to invest in these funds. And I've done it. Why not? If the ducks are quacking, as they say.

Every VC in the Valley [likes] greentech because it's the first market they've ever seen where they can mitigate their risk by laying it off onto governments (ie taxpayers). The trick is to spread lots of hype and put pressure on governments (hence Kleiner hires Al Gore) so that governments will provide subsidies to keep these venture-funded startups alive until they can be flogged off onto the public markets. They'll sell these stocks to dentists and they'll use the same pitch that Toyota uses on the Prius -- sure it's overpriced, but think how good you'll feel. These will be IPOs as a form of therapy, and the Birkenstock-wearing suckers will sing Kumbaya and talk about how capitalism is saving the world.

The great thing about this approach is not simply that it will let obscenely rich scammers get even more obscenely rich off the backs of taxpayers and suckers in the public markets, but that it also will enable these rich [jerks] to feel really good about themselves while they're doing it. They can run around feeling sanctimonious about doing something meaningful with their lives. They also can feel a little less weird and guilty about having so much money.

As they say, "follow the money".

As for me, am I really going to save the planet by buying those little "compact fluorescent lamps"?** I certainly won't intentionally pollute my space, but I'm fairly confident that I'm not in the world's top 10 polluters or wasters -- let's go after them first.

---

* Should it surprise us that the Earth appears to be warming up a little?

** Nevermind that almost a third of the Earth's carbon emissions are coming from forests burning in South America.

On the age of the universe

It's pretty often these days that some -logist (archeo-, geo-, etc.) is claiming that some find is many thousands or millions of years old -- fossils and DNA come up a lot. On the other side, the astrophysicists are often using the words "billions" and "light-years" in the same sentence, which also is mind boggling.

Now, in your other ear, devout religious people are claiming that the universe, including the earth, is only 6000 years old, based on the creation story in the Bible.

But "millions" and "billions" is pretty different from "6000". This isn't a small difference of opinion here! But how can creationists ignore all the scientific evidence? And how can scientists explain the incredibly impossible fortune that is the variety and complexity of "life" on earth?

Some ideas

We know what many of the scientists think -- that creationists are nuts. Or just self-blinded.

Creationists, on the other hand, think that either the scientists are flat wrong with their estimates (circular logic?). Or that "that one day [is] with the Lord as a thousand years" (2 Pet. 3:8), and that the Genesis account is God's days not ours -- uh, we're still only up to 13,000 years. (And Peter also says a thousand years is as a day, too, don't skip that part.)

My take

Why are we so limited in the possibilities we consider?

My answer in college to all this was that God might've built the whole thing 6000 years ago to appear in process, i.e. as a "steady-state system", which would "look and feel" like it was millions of years old, but that appeared stable to us and not still fluctuating around like all newly made things. Rather than creating stars, maybe he just created streams of light that would be arrive at the earth during the time of interest. Would any of that be too hard for God?

Of course not. My only problem with that now is that I don't think God would build something with the intent to deceive us.

Since then, my view has changed with the advent of 2 things: Quicktime, and computer-simulations.

* Computer simulations

I run simulations at work, where I start time at a random point, and then run through time at a much-accelerated speed to see what the computer models predict. We do this so we can figure out how something will behave without having to do all the complicated math manually. Much easier than all the math in those contrived problems in your high-school physics class...

So guess what -- I could run a simulation that started 50 trillion years ago, then run it all the way out through the present time (granted, at some pretty coarse time resolution) and have it finish in a matter of seconds. So "50 trillion years" equals "a few seconds for me" with the computers we've got now.

How is that possible? It's because I've got the whole thing defined and self-contained, and I'm the master of "time" in that system.

* Quicktime

Ever seen a movie clip of the history of the universe? (I have, though I can't find an example at the moment...)

Quicktime gives you a little slider that lets you slide back and forth through time with the flick of your wrist -- a trillion years with a 1-inch movement of your hand. See how easy that is?

So...

...if God is the "master of time" in this system, and can move through time as easily as He moves through space, the whole thing becomes really easy -- God inputs "1 trillion years" at the front, puts in a few "days" to get all the necessary pieces together, then lets it run. Who cares if the in-between time is {m|b|tr}illions of years -- the "master of time" just fast-forwards to the interesting part, when it's ready for people*. Is that too hard for God?

I'm not saying that's definitely how it is, Church doctrine is relatively silent on the matter except for a neat little scripture in the Book of Mormon that says, "all is as one day with God, and time only is measured unto men." (Alma 40:8)

I'm only saying that people needn't have their faith shaken by something this simple.

---

* Oh, don't forget to rewind a little and wipe out the dinosaurs first, the people don't need that much excitement. =)

Space junk

I'm always surprised at how people seem to think the space around the earth is full of junk. In this case they cite 5600 satellites still in orbit...

Wow that's a lot.

Right? Except venture a guess sometime as to how many cars there are in Tucson. Maybe fifty thousand! or more? And on their graphic of the earth, all of those would fit in a single dot easily! Now imagine that I blindfolded/earmuffed you, dropped you at a random location within Tucson, and gave you a bow and arrow and one shot -- what are the chances that you, in some random location, not seeing or hearing, would happen to hit a car with that shot? You think your chances of happening into space junk is good, toodleing around up there?

Space is *huge*, folks.

Your risk is measured by the probability of occurrence times the consequence of failure. When it comes to space junk, the "probability of occurrence" of a collision is terribly low. No, no -- what you need to worry about is the "consequence of failure", which is terrible, as space junk (or you) tends to be flying at thousands of miles an hour.

Getting hit by a wrench flying many times faster than a rifle bullet sounds painful. Very unlikely, but very painful.

Life in space

A few interesting tidbits about living in space, from Discover Magazine.