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Comment: Re:This again? (Score -1, Troll) 434

by justthinkit (#49597025) Attached to: New Test Supports NASA's Controversial EM Drive
Spring-And-Loop Theory predicts that its version of "virtual particle pairs" -- dubbed springs -- cause electrons to move at one-tenth of the speed of light.

100 years ago, those "virtual particle pairs" were called the ether. The ether doesn't go away, just because SR said it wasn't there and the M-M expt couldn't detect it.

"e/m", in Spring-And-Loop Theory, is "spring bumps". In the NASA expt., they are firing microwave energy (i.e. spring bumps) at "space" (i.e. springs). The springs have nowhere to go, since every Planck-unit of the Universe is full of them. So they have no choice but to push back. Immovable spring objects vs irresistable bump force.

Mod stalkers: this would be where you down-mod this comment, typically with the non-meta-moderatable "overrated" mod, usually doing this several days after the thread's start so that few will notice or have a chance to reverse your handiwork.

Comment: Re: Apologies for posting something on topic (Score 1) 120

by justthinkit (#49584151) Attached to: Russian Cargo Mission To ISS Spinning Out of Control
Ok, you pass Physics 100. Now back to the problem at hand.

If this was a simple case of the capsule being put into a spin, and then all forces on the capsule stopping, it would be trivial to send the capsule a signal to "fire thruster x for y seconds" to stop the spin. I am sure this is done all the time.

Yet the spin continues...

The logical conclusion is that something is continuing to impart rotational force to the capsule. Something stuck doing this. With the only somethings that checks all the boxes being navigational thrusters.

Comment: Apologies for posting something on topic (Score 4, Insightful) 120

by justthinkit (#49577091) Attached to: Russian Cargo Mission To ISS Spinning Out of Control
(1) spinning is caused by force
(2) more force, unless purely rotational = higher speed
(3) higher speed = higher orbit
(4) 20km higher orbit is not much -- consistent with a small engine (like a thruster) causing it
So, (5) keep guessing what the problem is

My guess: a thruster stuck open...

Comment: Re:Fluoride in drinking water isn't necessary (Score 1, Interesting) 314

by justthinkit (#49573889) Attached to: Feds Say It's Time To Cut Back On Fluoride In Drinking Water

Then there's the issue of toxicity, which apparently is essentially nil

Spectacularly wrong.

When you type "fluoride" into Wikipedia, the second auto-suggest is this "Fluoride_toxicity" page.

Then there is this paragraph on an otherwise pro-fluoridation page: "In India an estimated 60 million people have been poisoned by well water contaminated by excessive fluoride... The effects are particularly evident in the bone deformations of children."

At another pro-fluoridation page, we learn that the natural fluoride levels causing all those poisoned East Indians is 3 to 6 mg/l. Just 6 times the original US national standard forced on two-thirds of the population for the past sixty years.

The normal rule of toxicology is a safety factor of 100. About 100 cups of coffee will kill us, for example. One baby aspirin is 1/200 of the lethal (ld50) dose for an infant. Same as one 200 mg Ibuprofen. But a day's maximum ibuprofen dose is 6% of lethal. One cigarette is 1/80th of lethal. The average US salt consumption of 3.5 g/day is 2% of lethal...and common sense tells us we eat too much salt, on average.

Fluoride's ld50 is 50 mg/Kg. 8 glasses of water is about 2000 grams. Fluoridate at 1 mg/l, we get 2 mg of fluoride just from the water. That is 4% of lethal. And does not include at least 15 other sources of fluoride in our diet.

Stats in the last two paragraphs drawing from "Toxic: How Science Measures Harm"

tldr? Fluoride is more toxic than lead and almost as toxic as arsenic - common knowledge

Saying that something more toxic than lead has "essentially nil" toxicity is my idea of wrong.

Comment: Re:I'll be happy with one thing... (Score 1) 125

by justthinkit (#49567281) Attached to: Smart Headlights Adjust To Aid Drivers In Difficult Conditions
For the past year I've made a conscious effort to disengage my mind from the negative aspects of driving. My best solution is to drive with an engaging audio book or podcast playing. Instead of trying to change the behavior of other drivers, I'm working on self-improvement.

Comment: Re:How did he even get that job? (Score 1) 164

You do not "conquer" this challenge yourself, as you might by biking up the col de ventoux, or by free-climbing el-capitan. There is great expense involved, and you would need support from what is practically an aboriginal people. (You also cannot actually survive the summit, so you need all of industrialized society behind you to supply you with air/gear).

He did

Comment: Re:World's best? (Score 1) 89

And it is not as if Bluff is the best ranking place either. Most of the names there I've never even heard of. The Magician isn't even listed on page 1 (top 50), yet in a single tournament he won 4 times what Polk has won over an entire career. Phil Ivey & Huck Seed are also missing from page one, in part because they are big cash game players.

I imagine Polk is some very average player who got roped into this project and so, to give the project credibility, they trump him up into the stratosphere.

Today's scientific question is: What in the world is electricity? And where does it go after it leaves the toaster? -- Dave Barry, "What is Electricity?"