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Comment Re:Hmm (Score 1) 118

First, water vapour is opaque at visible frequencies, but the sun emits over a very wide band, most of which will totally ignore clouds. For something like this, you'd use radio astronomy. The sun is a superb radio source, easily strong enough to compete with terrestrial sources, especially if you pick the right frequency.

Second, no it wouldn't. It wouldn't be triggered by the presence of detecting light on the optical spectrum, but the presence of a specific alignment. So you only ever synchronise when you hit exactly the correct point.

You then want an interferometer to observe the sun, where the centre of your virtual dish is precisely the meridian. When the centre of the sun is precisely midway across your telescope's field of view, you transmit a synchronisation pulse.

Thirdly, a leap second is introduced every 21 months or so. If we assume a month of 30 days, that means you have clock drift of 1/630th of a second per day. You could miss a lot of days before the maximum possible error exceeded the minimum error in the clocks used. The risk of time travel would be zero.

Comment Re:How do you measure accuracy? (Score 1) 118

The chief benefit of a quantum gas clock is that it is able to measure time accurately enough to measure even small relativistic effects. (The change in the speed of time from a vertical displacement of ten feet is observable.)

Redefining a second according to such clocks won't cause any serious headaches - most users won't notice the difference, and those who would likely already use quantum gas clocks.

But it would make a difference in what they publish, as the intervals of time would have genuine meaning. (It's hard to talk about attosecond intervals when the error bars of what a second actually means will swamp the interval you're measuring.)

The chief benefit for synchronising to a quantum gas clock is that the error you inevitably introduce into the system is much smaller than the error of the atomic clock.

Comment Hmm (Score 4, Interesting) 118

Instead of faffing around, do this:

1. Install a quantum gas clock as the planetary timekeeper. It's much more accurate than an atomic clock. Place this at the Greenwich Observatory.

2. Agree on a fixed alignment as the start of a day.

3. Place a sensor at Greenwich which detects when that alignment occurs. This resets the counter for the quantum gas clock, so a second always starts when the alignment occurs.

4. Synchronise all atomic clocks to the quantum gas clock.

There is now a daily reset which is at a much higher resolution than most computer clocks (but within the nanosecond resolution Linux supports). The system itself adds and removes fractions of a second as needed with no need of political decisions. This correction will always be smaller than natural clock drift, so is inside the error bar software is already designed to handle.

Comment Basically, we need to buy time. (Score 4, Insightful) 130

Humans have been way too slow and the lead time between change and effect can be 20-40 years. We're locked in to worsening conditions until between 2045 and 2065.

But it'll take until 2060 before meaningful action starts, because humans only act after the disaster. It's a tendency baked in to how we operate and how we think.

So we need the engineers to act now, so that when we do finally act as a society, it's not too late.

Comment Re:Prohibition Yay!! (Score 1) 194

I don't think it's either relevant or useful. Vitamin A is deadly in excess. So is oxygen. If you measure only the effects once you exceed the toxic threshold, you won't get an accurate profile. You need to know what the benefits are at the therapeutic threshold, AND you need to know what controls you can add to keep things in the therapeutic range.

(Alcohol in low doses impairs brain development at any dose, but it also diversifies and strenthens the microbiome, and microbiome health improves brain function. This is an optimisation problem.)

Comment Re:Prohibition Yay!! (Score 0) 194

Alcohol, in small quantities, is extremely beneficial for your microbiome. It is a mutagen, so kills off bacteria that are fragile and diversifies the bacteria that are healthy.

Alcohol is only dangerous in excess, which is just as true for oxygen, iron, vitamin c, etc. True, vitamin c overdose doesn't cause psychotic behaviour, but there will be extremely healthy substances that certainly do. Danger in excess is not a valid reason for a ban, but would be a perfectly reasonable reason for better controls.

My recommendation, though, would be to start with a more European approach to alcohol. Alcohol abuse is, in part, a consequence of mystique. (Damn, those mutants get everywhere!)

De-mysticise alcohol and you'll find abuse levels drop. You'll still want better controls, but it's a critical starting point.

Comment Yes, no, maybe (Score 1) 104

It's really a reimplementation of a couple of older OS'. But so is Linux. Linux did Unix better than many commercial Unices, so won. It'll be 10-15 years before we'll discover if this new OS is a better AS/400. I think we should allow for that possibility.

But it doesn't sound like the developers have a good understanding of what has been tried or what is needed for the OS to be useful. So I'm not holding my breath. Still, that can change.

From what I'm seeing, this OS might be interesting for running virtual machines. Linux and Windows are very heavy for a VM host, a VM host doesn't need a lot of what is present in these OS', but would benefit considerably from some of the benefits listed.

Might. Just because something does something useful well doesn't mean it can do enough well and doesn't mean it does anything better than a properly-configured alternative.

I want to see how this OS develops, but I think it'll be a niche OS. Which is fine, there's value in that.

Comment Re:Suicide while giving testimony? (Score 1) 148

I think it safe to say that the number of police in Mensa isn't reflective of their percentage of the population.

I also think it safe to say that in election years, nobody wants to accuse a major political donor who might donate to the wrong person. Remember, police chiefs and judges are elected in much of the US.

And it's also pretty safe to say, in times of economic hardship, police aren't going to invest lots of resources into cases they're not confident they can score a court victory on. They're going to focus on cheap cases they've a good chance of winning on.

These seem more likely factors than any outright conspiracy.

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