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Comment Re:High pitched noises (Score 1) 294

I wonder how much of the occasional health panic that springs up around wifi - and indeed other technologies - can actually be attributed to the high pitched hums that can be emitted by badly manufactured devices.

It may be in your case, but I don't think that's the cause in most cases. I can also hear very high pitched sounds (transformers, bats), and while they can prevent me from sleeping, they don't make me sick otherwise.

I think the more general mechanisms at work are mass hysteria and the nocebo effect (placebo's evil twin), as evidenced by this story.

Comment Re:So Space Whales? (Score 1) 312

the surface, even though it would be frozen solid in about 6 seconds after exposure to space

Seems I read too fast and missed some crucial words. So that's more probable.
But I think it would look more like an icy explosion of gas, like a comet tail. My guess is that it would be too violent to allow a crust to form.
Of course, putting a large volume of water in space at once is a hypothetical scenario.

Comment Re:So Space Whales? (Score 1) 312

even though it would be frozen solid in about 6 seconds after exposure to space

That's Hollywood science. It would actually start boiling and freezing at the same time.
If it managed to form an icy crust, this would stabilize the pressure and stop the boiling and freezing.
If it was massive enough, the gaseous water would form an atmosphere that would also stabilize the pressure. Otherwise it would probably just boil away into space over time.
With the pressure stabilized, it would only lose heat through black body radiation, which would take a long long time to freeze it because water holds large amounts of thermal energy.

Comment Re:FSVO "about" (Score 1) 171

The interesting thing is that the vast majority of the universe is in the "everything else" zone.... contemplate that one for a while...

Hmm, I don't think this is correct, depending on what you mean exactly.

When we talk about the universe, we usually mean the observable universe. Since we receive light from all parts of the observable universe (it's observable after all), that means we are in the future light cones of those locations (each roughly an expanding sphere in 3D+time). If we can see something, it can effect us.

But, not all of those places are in our future light cone. Because of the metric expansion of space, which causes accelerated growth of the universe, our sun's light will never reach the outer regions of the observable universe, and we will never be able to travel there unless we find some way around the restrictions of general relativity (unlikely).

Comment Re:How is this news for nerds? (Score 1) 80

Geosynchronous, and especially geostationary orbit exists. So while you're correct, there's nothing to stop us from putting an object into decaying orbit where atmospheric impact will not cause significant enough friction to burn it out.

We just choose not to.

The ISS orbits between 330 km (205 mi) and 435 km (270 mi).
Geostationary orbits are at 35,786 km above sea level. That's about 35,000 km higher, and about 1/11th of the distance to the moon.
We choose not to put stuff there because:
a. Its expensive to put stuff in such a high orbit (more powerful rockets, more fuel)
b. It's pretty far from earth, so not very convenient to get to/from, especially in emergencies.

Furthermore, an object in a decaying geostationary orbit (going at about 3 km/s) would speed up along the orbit the closer it gets to earth (basic orbital mechanics), so eventually it would still have enough speed to incinerate largely in the atmosphere.

Any stable orbit has an associated speed, which is what Deadstick was saying. You seem to imply that we choose that speed so stuff will burn up on reentry, which is nonsense. It is estimated that 25% of a large satellite will reach the ground. At best they control (speed up) the orbital decay, so that debris will splash down in an ocean.

Comment Flex is not dead yet (Score 1) 227

From the Apache Flex webpage:
What happens to my projects if Adobe Discontinues the Flash Player?
It is true that current Flex projects are tied to either the Adobe Flash Player or Adobe AIR. We have been making great strides to compile projects to native JavaScript, therefore bypassing the Flash Player in the browser. Adobe has made a commitment to support the Flash Player and our current runtime for at least 5 years from the time they donated the project to Apache.
--
See for example the FlexJS project, that intends to run Flash directly on a JavaScript VM instead of the Flash Player VM.

Comment Re:I think... (Score 1) 530

The reason why clocks appear to slow down at high speeds is that the atoms in the clocks used for the experiments are simply decaying less (because they expend less energy at higher altitudes and higher speeds) than ones that didn't get to move so fast. Because the timing of a second is measured in the half-life decay, any changes to that decay rate will also throw off the clock itself. Mechanical clocks have numerous moving parts that get thrown off by the change in speed, and even electrical clocks still have to deal with changes in the oscillator speed and material resonance.

As I explained in a reply to the parent post, GPS clocks are actually faster than ground clocks.

Furthermore, atomic clocks don't use radioactive decay. Instead they include an atomic oscillator inside an electronic circuit so the whole oscillates at a very precisely defined frequency. The oscillation comes from Cesium/Rubidium atoms with electrons that move from ground energy levels to an excitated level and back. See http://en.wikipedia.org/wiki/Atomic_clock#Mechanism

The reason why clocks appear to slow down is because time is relative, and depends on the relative speed (special relativity) or the difference in gravitational field strength (general relativity) of the observer and the observed.

Comment Re:I think... (Score 2) 530

Well, consider that relativity tells us that the satellites zooming up above us have slower ticking clocks.

Actually, the GPS satellite clocks run 38 microseconds faster than ground based clocks.
This is because they are not moving fast enough (special relativity: faster means slower clock) to counter the general relativistic effects (stronger gravitational field means slower ground clocks).
Both clocks seem to be slower for an observer in free space.
http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html

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