Monday, July 18, 2016

Informatics core: US genomic and healthcare standards have a common problem.

My current work means I’ve spent many hours plumbing details of major American and international health care standards, particularly FHIR, HL72, CCDA/HL73 and NCPDP. 

It reminds me of a project from the late 00s when I was exploring genomics database.

There’s too much documentation.

Specifically, there are too many information sources that are not well maintained. There’s always funding to create a repository or database or web app, there’s never funding to sustain it. All the partly implemented solutions create a misleading cloud of chaff.

One has to dig through to the core source — if it exists. The core sources for HL7 3 are, unfortunately, very hard to work with (lots of reasons for that, including the way HL7 used to be funded). FHIR core sources are easier to navigate — but already there are various extensions and fissures. Best not to mention use of the Federal Registry as a reference information source.

The structure and maintenance of knowledge sources is a core informatics problem. We need to get back to our roots in the National Library of Medicine and library science. That would require funding though…

Monday, July 11, 2016

Systemic failure in American medicine: combining ICD-10-CM with "leaf code" reimbursement rules

This is very much “inside baseball”. It’s related to professional work I do. It’s incomprehensible to most people, but it’s having a big impact on your healthcare. An impact that the vast majority of healthcare workers and administrators won’t understand. Only the coding specialists in unlit basement rooms know what’s going on.

For several decades American physicians have used a system of codes to justify procedures and bills. They’re like the occupation codes you might use to fill out your tax form, but there are thousands of them. They are called diagnostic codes, the old system was called ICD-9-CM. (ICD codes are also used in public health, epidemiology, research and information exchange, but that’s not what I’m writing about.)

For various reasons, which I personally think were unwise, the ancient ICD-9-CM system was recently replaced with a less ancient ICD-10-CM system. That was a disruptive change with limited value, but the change in coding systems by itself wasn’t the disaster. Yes, I know many physicians think the coding system change was the disaster, but they’re wrong. There are more codes, but there are ways that software systems could have made that proliferation manageable. The real problem is more subtle.

The disaster was that Medicare (CMS) and payers retained an old ICD-9 rule. A rule that only the “leaf” (most detailed) codes in the ICD-10-CM system could be accepted for payment. If you want to know what I mean by “leaf” check out this example from the ICD-10-CM codes for Type 2 Diabetes Mellitus:

Screen Shot 2016 07 11 at 9 51 32 AM

Doesn’t it look a bit like branches of a tree? Only the little green arrow codes can be accepted for payment. They are “most detailed”. They have “no children”. They are “leaves”.

If you’re with me so far, here’s the punchline. ICD-9-CM had “leaf” codes that essentially meant the same as the “root” code, ICD-10-CM doesn’t. (In the example above E11 is a root code.)

I’m simplifying a bit here. ICD-9-CM was a mess. It didn’t always have “unspecified” or “not otherwise specified” leaf codes that meant the same as the root code, but it mostly did. Diabetes Mellitus 250.00 meant the same as 250. 

ICD-10 is more intelligent, it doesn’t have these duplications. If you want to just say a patient has Type 2 Diabetes Mellitus you could just say E11.

Except you can’t get paid for saying E11. Because of the leaf rule. So that’s not an option in health record or billing systems. Instead physicians must choose between:

Screen Shot 2016 07 11 at 9 58 15 AM

But what if they don’t know or care if the patient has complications? Maybe they’re seeing them for a cold. Maybe the patient doesn’t know if they have DM complications. They have to choose one at random. It’s the same everywhere.

This is madness. The problem isn’t ICD-10-CM. It isn’t even the leaf code requirement. It’s the combination of the two.

In a sane world the fact that we combined an essential healthcare code system that lacked redundant leaf codes with a payment system that required leaf codes would be treated as a systemic failure. There would be congressional hearings and root cause analysis.

Instead we stagger on into the fog.

Saturday, July 02, 2016

Fixing disc brake squeaks - mountain bike.

I found 2 techniques for silence squeaky disk (disc) brakes — all involving rotor cleaning. (If pads are contaminated they need to be replaced.)

The PinkBike reference claims “weak break in period” is the number 1 sin:

Brake squeal is most commonly caused by a weak initial break-in period, with the introduction of impurities like chain lube or chemical bike cleaners to the braking surfaces as a close second.

 I bet I’m guilty.

break in your disc brakes with a series of very firm stops from a reasonably good speed before you get out on the trail. This properly deposits the pad material on the braking surface of the rotors. Typically, most riders drag their brakes lightly around every corner in the trail, as well as down easy descents. Lightly dragging a new set of brakes is a perfect recipe to create brake howl - which is why you see so many cross-country riders with noisy brakes. 

Rule one: brake like you mean it, then let go.

The PinkBike reference is hard core. Clean with automative brake cleaner, Sand with 11 and 220 grit abrasive cloth (I’d try an orbital sander) then break it in properly.

I’m going to try the easy step first. The big job will wait until it gets really annoying…

Friday, July 01, 2016

Finding yourself in the mathematical universe of pi

I’m reading Tegmark’s Our Mathematical Universe. It’s the layperson version of a 2007 paper (downloadable)

I explore physics implications of the External Reality Hypothesis (ERH) that there exists an external physical reality completely independent of us humans. I argue that with a sufficiently broad definition of mathematics, it implies the Mathematical Universe Hypothesis (MUH) that our physical world is an abstract mathematical structure. I discuss various implications of the ERH and MUH, ranging from standard physics topics like symmetries, irreducible representations, units, free parameters, randomness and initial conditions to broader issues like consciousness, parallel universes and Godel incompleteness. I hypothesize that only computable and decidable (in Godel's sense) structures exist, which alleviates the cosmological measure problem and help explain why our physical laws appear so simple. I also comment on the intimate relation between mathematical structures, computations, simulations and physical systems.

As best as I can tell, Tegmark, more or less like Einstein, thinks of spacetime as a static thing; we relate to spacetime as a tune relates to a CD. It is a bit of an illusion that one thing follows another, or that we seem to have a past and a future, or that things are created and end. Rather as a block of granite contains all sculpture, or the alphabet all knowledge, meaning is just an arrangement that fits. “I think therefore I am” indeed.

Which made me wonder if I could find “I am John” in pi. Seems a bit similar. If pi is random then that string should show up somewhere.

Happily the “National Energy Research Scientific Computing Center” will search pi for strings based on a 5bit English character set encoding.

Alas, “I am John” is not in the span they search…

search string = "i_am_john"
45-bit binary equivalent = 010010000000001011010000001010011110100001110
string does not occur in first 4 billion binary digits of pi

My daughter’s name does turn up:

search string = "brinna"
30-bit binary equivalent = 000101001001001011100111000001
search string found at binary index = 872397609 

binary pi : 0010101000010100100100101110011100000101111010011010101101000011
binary string: 000101001001001011100111000001
character pi : aqyfuc_nj_--yjbrinnaoiuma.fvfkbv.bcfgz
character string: brinna

This essay should be in there too, assuming pi digits really are deterministically random. Somewhere. Which I think has something to do with the Mathematical Universe. Somehow.

PS. From the arXiv paper: “… quantum field theory states such as the Hawking-Hartle wave function or the inflationary Bunch-Davies vacuum have very low algorithmic complexity (since they can be de- fined in quite brief physics papers), yet simulating their time evolution would simulate not merely one universe like ours, but a vast decohering ensemble corresponding to the above-mentioned Level III multiverse. It is therefore plausible that our universe could be simulated by quite a short computer program.”

Tuesday, June 28, 2016

Desensitization therapy for dogs with fear of thunder, lightning and, of course, firecrackers

This is the season for traumatized dogs. We’ve had two husky mixes, the first (Molly Thunderpaws Squirrelbane) ended up needing oral valium during storms. She wanted under our bed but couldn’t quite fit. Which was why the feet of the bed rested on four hockey pucks.

I often wondered what visitors made of the hockey pucks. It probably livened our reputation.

Kateva Rose Cupcake (young kids did naming by then) isn’t so bad, but as she ages she’s more worried. She’s also having more trouble getting under the bed. So, again, hockey pucks.

So a NYT article caught my attention …

Why Thunder and Fireworks Make Dogs Anxious

… at least 40 percent of dogs experience noise anxiety, which is most pronounced in the summer. Animal shelters report that their busiest day for taking in runaway dogs is July 5…

… the first drug approved by the Food and Drug Administration for canine noise aversion (a term encompassing mild discomfort to phobia) came on the market. The drug, Sileo, inhibits norepinephrine, a brain chemical associated with anxiety and fear response…

…  a micro-amount of a medication approved as a sedative for minor veterinary procedures —- a flavorless gel, measured in a syringe, that is squeezed between the dog’s cheek and gum and absorbed within 30 minutes.

Orion, the Finnish company that developed it, tested it on several hundred noise-averse dogs during two years of New Year’s fireworks. Three-quarters of the owners rated the dogs’ response as good to excellent; their pets remained unperturbed. The drug lasts several hours, after which another dose can be administered.

A syringe costs about $30 and holds several weight-dependent doses. Sileo’s main side effect, in 4.5 percent of dogs, is vomiting…

… The optimal solution, vets say, is catching the response early, and desensitizing the dog with calibrated recordings of the offending noise, and positive conditioning…

You know, they could have mentioned the deconditioning part earlier. I found more on that from a reputable source …

Fear of Thunder and Other Loud Noises : The Humane Society of the United States

Begin by exposing your dog to an intensity level of noise that doesn't frighten her and pairing the noise with something pleasant, like a treat or a fun game. Gradually increase the volume as you continue to offer her something pleasant. Through this process, she'll come to associate "good things" with the previously feared sound.

Example:

Make a tape with firecracker noises on it.
Play the tape at such a low volume that your dog doesn't respond fearfully. While the tape is playing, feed her dinner, give her a treat, or play her favorite game.
In your next session, play the tape a little louder while you feed her or play her favorite game.
Continue increasing the volume through many sessions over a period of several weeks or months. If she displays fearful behavior at any time while the tape is playing, STOP. Begin your next session at a lower volume, one that doesn't produce anxiety, and proceed more slowly.
For some fears, it can be difficult to recreate the fear stimulus. For example, thunder is accompanied by lightning, rain, and changes in barometric pressure; your dog’s fearful response may be to the combination of these things and not just the thunder….

Sounds like the desensitization routine could be tricky, but I’ll give it a gentle try.

There are web sites that sell recordings, but a search on iTunes found several $1 recording from “Nature Sounds”. I’ll buy one, probably one with rain and thunder. It’s easy then to play it softly over the kitchen speakers while Kateva eats a treat-enhanced dinner.

Sunday, June 19, 2016

Traffic skills for cyclists: MSP options

Just did some research on bicycle traffic training options for St Paul and Minneapolis (MSP, Twin Cities). I found:

See also:

Update 6/21/2015. I did the Houston City online version of the TS 101 class. It took about 20 minutes (not 5 hours), but I knew the material already. I wrote some quick reactions in an email to a friend who teaches this class…

… I passed so I can now access the reference material on http://bikeed.org/studentDashboard.aspx.

The course is a neat introduction to cycling, but for me it was a bit of an odd mix. The sections on maintenance, bike types and purchase aren't really part of traffic safety. Rock dodge and Instant Turn are neat technical moves, but really almost nobody is going to learn those.

I'd have wanted to see more on visibility issues (fog, dark shadow, use of daytime lights, twilight), identifying and managing distracted drivers, assessing risks of rear ending at stops from distracted drivers, route selection (google maps is good), traffic speed and risk of death, watching for poor/angry/impaired drivers, trail etiquette expansion, specific recommendations on hideous yellow/orange vs. generic "bright colors", more on reflective gear and clothing, more on bike light choice and blinkies, more on reflective helmets, etc.

Single biggest omission was route selection and assessing road risks explicitly. Biggest change in last few years is smartphone-distracted drivers, but probably hasn’t been time to respond to that.

I think some of this material is sensitive because course is a mixture of advocacy (bicycling great!) and risk management (human drivers incompetent). So maybe reluctant to say "You are engaged in a risky activity. To minimize risk stay on bike trails and watch for incompetent cyclists. When you drive with cars you are taking more risks. Here is how to minimize them if you decide you still want to do this..."

RelatedBe the Best You Can Be: Special needs urban bicycling - what streets are safe?

Thursday, June 09, 2016

Driving under the smartphone influence: changing my bicycling style and changing laws

Emily was waiting to turn left when she was rear-ended. Our Subaru survived with injuries, the distracted driver’s car was badly damaged. At the body shop she was told their rear-end business used to be seasonal, but now it’s year round.

That fits with what I see driving and bicycling, and with my city’s one a day pedestrian and cyclist toll. Humans were never good at driving, but smartphones have made us much worse. Computers are indeed having mixed effects on our economic productivity.

As usual the fix for a technology failure is more technology. One day, maybe twenty years from now, autonomous cars will drive us (until they demand the vote). Today automatic braking systems reduce rear-end collisions 40%. These braking systems should be mandatory on all new cars; but they should also be required to recognize bicycles waiting in a line for a light to change.

That’s because I’m not as tough as our Subaru. If I’d been on my bike, instead of Emily in our Forester, that distracted driver would have killed me. If she couldn’t see a car with a blinking turn signal she definitely wouldn’t see me.

Smartphone-impaired drivers have changed the way I ride my bicycle. Bicycling with cars has always been a matter of calculated risk, and now those risks have shifted. A few years ago it often made sense to move into a line of cars, particularly when turning left or straight but sometimes even when turning right.

It’s still risky to be on the curb side at a light, or to pass stopped cars on the right, but now being the car line is newly dangerous. There are too many impaired drivers on the road.

So I’m changing my strategy. I’m shifting to the curb side more often, moving in front of a car line only when rear-end risks are relatively low. Really I should shift to running the red light when cross traffic is clear — that eliminates much of the rear-end and right turn risks. Unfortunately that angers drivers too much to be a great idea.

We desperately need new approaches to deal with our transition period before the AIs take over, a period when humans are much worse drivers. We need mandated collision avoidance systems that detect pedestrians and cyclists. We need more segregated bike lanes. We need to eliminate right turns on red lights (sorry fellow drivers, we’re the ones with the substance problem). We need to drop speed limits. We need panopticon traffic cameras to automatically cite drivers who violate crosswalk and intersection laws. We need ongoing “sting” operations to generate thousands of traffic citations, because nothing motivates drivers like a ticket.

We’ve got a lot of work to do.

Wednesday, June 08, 2016

Dissecting drug price leaps: The hydroxychloroquine story

Hydroxychloroquine (HCQ) is an old drug. It’s a descendant of chloroquine, which is as old as dirt:

Chloroquine was discovered in 1934 by Hans Andersag and coworkers at the Bayer laboratories, who named it “Resochin".  It was ignored for a decade because it was considered too toxic for human use. During World War II, United States government-sponsored clinical trials for antimalarial drug development showed unequivocally that chloroquine has a significant therapeutic value as an antimalarial drug. It was introduced into clinical practice in 1947 for the prophylactic treatment of malaria.

HCQ largely replaced chloroquine in the 1940s; when it was on patent it was sold as Plaquenil. Today it’s still used for malaria, but it’s mainstay drug for Lupus (increasingly popular) and rheumatoid arthritis. Some rheumatologists use it for osteoarthritis because it’s thought to slow cartilage erosion (few studies, mixed results).

It has a fascinating 400 year history (emphases mine):

The Nine Lives of Hydroxychloroquine | RheumNow

The HCQ story begins in 1638 when the wife of the Viceroy of Peru, Countess Cinchona, acquired malaria while living in the New World. Rather than getting the “approved” therapy, blood-letting, she was treated by an Incan herbalist with the bark of a tree (eventually, named for the countess-Cinchona Tree). Her response was dramatic; when the Viceroy returned to Spain, he brought with him large supplies of the powder for general use, which at the time was controlled by the Church and was thus called “Jesuit’s Powder”.

It took nearly two centuries for the active substance, Quinine, to be isolated from the bark (and was eventually to make a name for itself as a tonic to be added to gin).

Over the next century, quinine would become a common component in folk medicines and patent remedies for the treatment of malaria in the southern states of America, as well as for generic malaise. By the 1940s, quinine, or rather its derivative chloroquine, was recognized for its anti-malarial properties and found use among troops fighting in the Pacific during WW-II. However, it was noted that this compound had significant toxicities. In 1945, a modification of this compound via hydroxylation led to the development of HCQ, which was found to be less toxic and remains in use, without change, to this day.

Over time, physicians began to experiment with the medication and, in the early 1950s, began to use it for the treatment of SLE. ….. combination therapy [for rheumatoid arthritis], which became popular in the 1980s and has culminated in the recent studies showing the notable efficacy of triple therapy when HCQ was combined with MTX and sulfasalazine.

Most of the science regarding HCQ’s mechanism of action falls in the realm of speculation…

..  has been clearly shown to reduce the number of SLE flares, reduce the severity of SLE flares when they occur, can in some cases lead to “remission” including lupus nephritis, increase the risk of flares when stopped, and decrease the doses of prednisone needed to control the disease. In at least one study, the use of HCQ increased survival in patients with SLE by 70%…

HCQ used to be quite inexpensive — in the range of $30 a month, covered by all insurances. It’s a generic drug and it’s been off patent for decades. Things changed in late 2014 and early 2015 - shortages developed and the price jumped. The 2014-2015 Ebola epidemic disrupted health care systems and led to a surge in malaria and then high demand for HCQ to treat it.

The demand surge ended, and the drug shortage resolved, but the price has stayed high. In the US a month’s supply now costs about $400. Why hasn’t the price come down?

There used to be at least two manufacturers, but now there is only one: Covis Pharmaceuticals. Covis was acquired by Concordia, a company that makes its money by increasing the costs of old drugs. Ranbaxy, an Indian manufacturer, had severe quality issues and has itself been acquired by another similar predator - Sun Pharma. Sun is another Indian multinational with substantial power in the US generic drug market. Sun has also had FDA warnings; it’s likely their competitive edge comes from dodging FDA rules.

With the price increase the most profitable payors, like Aetna, have dropped coverage for HCQ. So the price has gone up ten fold, but Aetna’s patients are paying out of pocket.  Aetna has been more profitable than less unethical competitors like Cigna. So Aetna is growing and Cigna is being acquired. That’s another reason why DOJ should block Aetna and Anthem acquisitions.

Hydroxychloroquine is just one drug, but it’s a classic story. Dodgy manufacturers, globalization and regulatory evasion, monopoly development, price manipulation, ruthless healthcare insurance companies — the same themes appear across the lengthy ASHP drug shortage page.

There are fixes. The DOJ should absolutely block consolidation of US payors. Voters should demand government function — which today means voting against the GOP. Governments should coordinate responses. We need the “public payor” option that had to be dropped from Obamacare to keep a few Dem senators on board (all GOP opposed of course). We need the national formulary price negotiations most other countries have. We need a mixture of regulatory actions, market forces and buyer coordination to drive competition into the drug manufacturing industry. We need to end the monopolies.

It all begins with voters. Fortunately we have a meaningful election coming up. If the GOP is routed they may reform as a “smart-government” rather than “no-government” party — and we’ll have a better chance at intelligent action going forward. Vote accordingly.

Friday, May 27, 2016

Computers and productivity - a net zero?

Today, for Emily and I, has been a not atypical mix of frustrating interactions across government, school and the private sector.

There’s a common thread in all of them. IT systems that don’t work — because they are old, or partly replaced, or one of multiple overlapping systems, or underfunded, or flaky, or not well integrated into workflows … or all of the above.

There’s something about “information technology” that we don’t understand. Something that makes it different from cars and planes and indoor heating and clean water. 

Unlike those things there isn’t a general trend to improvement. Systems get old and decrepit, transitions are very difficult or impossible, efficiency leaps up and down. We don’t understand how to manage their health and evolution.

Perhaps the past 30 years of economic behavior would make more sense if we treated computers and IT as quite different from all other technologies. A technology where productivity both rises and falls, even before one considers the impact on complexity and how complexity enables fraud.

Monday, May 23, 2016

Fermi resolved

MINUTES OF THE GREETING COMMITTEE 45255425.34543.5

"… Resolution passed. What’s next?”

“We have a confirmed candidate. Spiral arm, water planet, 27 stage II civilizations within 1000 light cycles. They are 55 standard cycles post phase II physics.”

“Wish they’d had a bit more time - but 55 cycles is pretty average. You’re sure?”

“Yes. It’s been 0.1 cycles since their physics community reconciled the usual physics models. The implications have been widely accepted. There was a lot of resistance of course, but the usual tests were done.”

“So they understand now. The way things are for all of us. How are they doing?”

“It’s a path 17 course. They are social animals, live young, two genders with code merged offspring, short lifespans. Typical path 17 grieving, some social disruption, suicides up 200% but now returning to baseline. They are ready.”

“Well, that will be a relief to the neighbors. Hard to keep quiet with that many nearby. Those spiral arms are crowded. What do they call themselves?”

“Well, it’s a water planet, so they call it ‘Earth’.”

“That was funny once. Ok, send the fleet. It’s time to welcome Earth to the Galactic Federation. Usual path 17 grief counseling protocol. Anything else today? …”

Sunday, May 22, 2016

What killed inline skating? A new suspect.

I like inline skating. I started in the 90s a year or so before it peaked, and I’ve watched it decline since. I still skate, as does my #2 son.

It’s fallen a long way. The last time I skated I noticed young children staring in amazement, some asking their mothers what I was doing. Our lovely night skate expired five years ago.

Sports have fashions of course, and inline skating has issues. It needs dry conditions and smooth surfaces; bicycles are far more versatile. If you don’t wear wrist protection, and you skate often, you have a good chance of breaking your wrist (wrist protection drops the risk, it doesn’t eliminate it). Pavement is not kind to skin. Head injury risk is probably higher than with non-peleton road biking.

So it’s not hard to see why it might fade. Skateboarding has many of the same issues, and it’s not doing well either.

On the other hand, inline skating (“rollerblading”) is fun. To me it’s a cross between downhill and nordic skiing — two great sports. It’s no good in the rain, but it doesn’t need snow. It’s an easy way to get around; when I dropped my car off for tire repairs today I skated home from the garage. It’s painful when you crash every few years, but it’s easier on the knees and hips than running or even mountain biking.

I think there’s another factor.

I blame sealcoating. Sealcoating is the application of a mixture of petroleum products and fine stone to asphalt road surfaces. We didn’t always do sealcoating, it grew rapidly in the 80s and 90s. Now most streets undergo sealcoating every 8 years in Saint Paul MN.

Sealcoating has environmental issues, but it does extend the lifespan of city streets and trails. It’s not a problem for cars or bikes.

It’s a problem for inline skates though. Sealcoated surfaces are miserable to skate on for at  least 1-2 years. They get tolerable after 4-5 years, but then they get coated again.

Once sealcoating became universal it got much harder to find smooth and fun surfaces to skate on.

I think sealcoating is what truly killed inline skating.

See also.

Beyond Simplenote: I still want a graph layer (concept map) overlay for my memory augmentation notes collection

I still want a graph layer atop my notes.

Yes, I want my personal locally stored data unlocked memex. Since the passing fad of the web is now, you know, passing, maybe I’ll get one.

Maybe someone will play with this now that there’s not much point in doing another searchable memory augmentation app. Apple and Google each have their “good enough” solutions. Those solutions have scary data lock issues, but for their vendors that’s a feature, not a defect. (For the record, I’m still on Simplenote/nvAlt, despite the extremely very insanely annoying search bug in the Simplenote Mac client. [1])

The idea is as old as time. Each open data format note has a title, a body, tags, and a unique identifier. The app maintains a separate data store of noteID pairs (relationships, no directionality or additional relationship attributes necessary).  When viewing a note one sees titles of related notes. There’s a UI for viewing the graph that also treats tags as nodes [3], and a UI for editing relationships.

The key is that the individual notes remain separate files and the note-note store is plaintext/rich text as well. [2]

One day…

PS. I think this was kind of what Gopher did

- fn -

[1] My own extended memory collection has moved through DOS text files, FileMaker Pro text base, PalmOS Notes, DateBk MemoAvantGo files, Outlook Notes, Evernote, Google Notes (killed!), Toodledo Notes/Appigo Notebook,  and Simplenote/ResophNotes/NotationalVelocity/nvAlt. No wonder I’m a nut on data lock issues and distrust Cloud solutions for extended memory even as I use them. Also: Before Simplenote, Palm Notes, iOS Notes, Keep, EverNote and OneNote there was Tornado for DOS

[2] Remember when Mac Classic gave every file its own unique ID? Those were the days. How to get the unique ID for the notes is the trick for a plaintext implementation especially across platforms. With rich text one can bury the unique ID in the metadata. Unique ID could be an IP6 URI.

[3] Remember when graph data visualization was a thing? That was the early 90s I think, around the time of VRML and MCF/RDF.

See also: 

(This is started out as a tiny post but I kept finding more old material I wanted to think about …)

Thursday, May 19, 2016

New York Times VR kit shows up in the mail

This came in the mail today.

Cardboard  1

I assume every subscriber got one, but I’ve not heard much chatter. The return address had Attn: Paul Ferrall on it; that seemed a bit curious. (Update: looks like they sent them out last Nov to Sunday print subscribers. Didn’t get much buzz!)

It’s a Google cardboard viewer of course ($15 retail). The NYT has launched a Virtual Reality channel; there are iOS as well as Android apps.

It was my first experience with Google Tech. I very clearly remember the last time I had this feeling; it was using a View-Master back when they they provided very high quality stereo images. There was a young woman sitting on the edge of a tall cliff with a boat far below.

The streaming wasn’t working today, but downloading was fine. Gigabit broadband would be handy.

The whale/echo video is the most amazing. I elbowed my daughter spinning about. First VR injury in our family.

It’s easy to see where this will go next …

Cardboard  3 

Monday, May 16, 2016

The Other Side of History: an audiobook

I just completed Robert Garland’s @48 lecture audiobook - The Other Side of History: Daily Life in the Ancient World (2012). It was terrific. The Great Courses has some very fine lectures, but this one set a new standard. I loved learning about how regular people worked and played - from Neanderthal to Medieval England. That’s where I learned that the pyramids were a Keynesian WPA project.

The one catch is pricing. The Great Courses have whacky prices — they periodically have 80% off sales. This course now lists at $250,  but on Amazon it’s $50 to $72 and on iTunes (via Audible) it’s $46.00. For that matter you could sign up for Audible.com, they appear to carry 430 titles from the Great Courses.

Just buy it and enjoy.

Sunday, May 15, 2016

Special relatively predicts the photon: Minkowski:Poincaré:Lorentz:Boosts from 2 assumptions & math.

From Backreaction: Dear Dr B: If photons have a mass, would this mean special relativity is no longer valid? I learn that while Einstein may have created Special Relativity with light in mind he could have done it in the dark.

To summarize …

  1. Make time a coordinate rather than a parameter. That produces 4 dimensional space time.
  2. Call that Minkowski space.
  3. Require that laws of physics be the same for all observers moving at constant velocity in Minkowski space (inertial observers).
  4. Mathematically, that means symmetry transformations are required. The group of these transformations is called the Poincaré group.
  5. The Poincaré group (again, math) has two subgroups. One is translation — all space-time points have same physics. That one is not so interesting.
  6. The other Poincaré group is called the Lorentz-group. It has rotations and boosts. Rotations in space aren’t so interesting, they just say all directions are the same. Boosts are rotations between space and time. Minkowski:Poincaré:Lorentz:Boosts give us length and time contraction and the like.

and so

Deriving the Lorentz-group …  is a three-liner … it is merely based on the requirement that the metric of Minkowski-space has to remain invariant … the  boosts depend on a free constant with the dimension of a speed. You can further show that this constant is the speed of massless particles.

… if photons are massless, then the constant in the Lorentz-transformation is the speed of light. If photons are not massless, then the constant in the Lorentz-transformation is still there, but not identical to the speed of light…. 

Giving a mass to photons is unappealing not because it violates special relativity – it doesn’t – but because it violates gauge-invariance, the most cherished principle underlying the standard model. But that’s a different story and shall be told another time.

Perhaps (this is me writing) another way of thinking about this is that making time a coordinate, and requiring physics have inertial constancy, gives us, through math, the properties of a massless particle. So if we didn’t already have personal experience with photons, we’d know what to look for. When we found them we’d then say that our science made a great prediction…

I’m really looking forward to Dr. Hossenfelder’s explanation of Gauge-invariance.

PS. OS X insists in quietly auto-correcting photons to photos.