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Comment 3-way calls (Score 1) 445

I could never figure out how to do those...

Actually I have a fancy VOIP phone which I regularly use along with all the other communication tools listed. I regularly use Video conferencing and skype but the phone has been a very useful fallback when internet connectivity isn't where it should be.

Comment Re:I Wish (Score 1) 259

The arrow of time refers to the fact that we perceive a difference between the past and the future: we remember the past, but not the future. That's explained adequately by noting that entropy tends to increase and the universe, for some reason, was in a low entropy state in the past.

What they've found is that, at least for b-mesons, going forward in time is different than going backward in time, presumably in addition to the rest of the universe accumulating entropy. It's as if there was a fundamental difference between moving "north" and moving "south" in empty space.

Yes! Exactly!

Comment Re:I Wish (Score 2, Informative) 259

The arrow of time is the reason why random bits of shrapnel and chemicals don't fly together and "un-detonate" to become hand grenades. In one direction of time, entropy in the universe always increases; in the other, it always decreases. The question is, why?

The reason is very simple. Entropy is a measure of the probability of a particular outcome. The statement that "entropy increases" is simply the statement that the most probable thing to do happen is almost always the one that does happen. The "almost always" is a fantastically high probability. For example if I through a 1 cm cube of of aluminium at 26 C into a lake where the water is at a temperature of 25 C, there is something like a 10 ^-(10 ^10^23) chance that heat will from the lake into the aluminium cube and cause it's temperature to rise. If it did this the entropy of the Universe would decrease.

What this experiment observed is profound and extremely interesting. For some reason that isn't known, the Universe prefers that certain microscopic and reversible processes occur with a greater probability if time increases.

In other words there truly is a preferred direction to time which independent of tautology that the Universe is constantly evolving into a more probable state.

Actually this result is was first observed in K-mesons but this new result in B-mesons has much greater significance and confirms the previous observation.

Comment Re:yet another solar tech not available to the pub (Score 1) 237

You didn't include installation and ancillary mounting costs. These are fixed and are proportional to the area of the deployment. That 1$/watt panel ends up being $2/watt deployed on some ones roof.

Also the 12 hours/day at 50% intensity amounts to 25% insolation. That is close to the best in the world. Where I live in Melbourne annual insolation is around 12% - half of your estimate.

So currently panels cost twice as much and provide half the output you estimated.

You only win on decreased deployment costs if you can get the efficiency up.

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Some programming languages manage to absorb change, but withstand progress. -- Epigrams in Programming, ACM SIGPLAN Sept. 1982

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