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Comment: Re:Current minimum is 30 min by car. (Score 2) 149

by drerwk (#49041303) Attached to: Mooted: An Undersea Link From Finland To Estonia
It may be people at work were kidding me: However, apparently it is common to drive into the sea at Talinn.
http://www.topgear.com/uk/phot...
http://www.bencoombs.net/page7...
As for temp:
Helsinki Airport recorded a temperature of 34.0 C (93.2 F) on 29 July 2010 and a low of 35.9 C (33 F) on 9 January 1987. - so maybe I'm thinking with wind chill.

Comment: Current minimum is 30 min by car. (Score 1, Insightful) 149

by drerwk (#49039501) Attached to: Mooted: An Undersea Link From Finland To Estonia
I had the great pleasure of staying in Helsinki for Dec/Jan - love the Finns. It finally got down to -44 or so and there was much celebration at work as the gulf had frozen over and the booze run to Tallinn could be done by car. I gratefully declined the invite to go along for the ride.

Comment: Re:100% Pure USDA-Disapporoved Bull (Score 1) 119

The juror is there to determine the facts of the case. The prosecution and defense are both giving their sides. The jury may decide that there's reasonable doubt, doubt but it's not reasonable, or no doubt one way or another. It's their call. They really don't care about the agent's theories, because they are not FACTS.

I assume that the agent's theories were developed to support some set of facts that he had at hand and that those facts can still be pointed to in support of the previous theory. I've not studied this case in any detail, but I know that the goal of any prosecutor is to get a conviction, sometimes more so than being sure they have the right guilty party on trial. While in the ideal world, justice and truth might converge, in our world justice is on a clock and the truth is not.

Comment: Re:100% Pure USDA-Disapporoved Bull (Score 4, Insightful) 119

by drerwk (#48824549) Attached to: Silk Road Trial Defense: Mt. Gox CEO Was the Real Dread Pirate Roberts
I don't think the soundness of the theory is so important to the jury as is the fact that the agent was sure this other guy was the DPR, and now the agent is sure the defendant is the DPR - the agent has to admit to being wrong before and can be asked why in 6 months he would not have a new theory about who really is the DPR. I think it leaves a lot of doubt about the certainty the agent ought to feel about his theory.

Comment: Re:Science, bitches, that's *how* it works! (Score 2) 197

by drerwk (#48635871) Attached to: Quantum Physics Just Got Less Complicated

"wave-particle duality is simply the quantum uncertainty principle" gets a "no shit" straight away from me, though I guess a rigorous proof of it is kind of news.

That's how science work.

That more about how math works. Physicists did not care that the calculus of infinitesimal was not rigorous; see especially the Dirac-Delta function. It gave them answers that agreed with experiment which for a Physicist is the best proof. http://en.wikipedia.org/wiki/I...

Comment: Re:Someone doesn't understand basic relativity (Score 1) 81

by drerwk (#48618811) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship
Right, but the sentence you are make fun of is talking about stabilizing the rocket as it is coming back into the atmosphere, ass first in a no longer particularly aerodynamic configuration as it is missing the whole second stage and payload section. Flight stability in the nose going first direction is much better than in the engine going first direction. They are not complaining how hard it is to go that last 10m to the landing; I agree with you that stability control at that point is pretty easy. You know the first attempt they made for power re-entry failed because the axial rotation of the booster caused fuel starvation to the engine due to centrifigal force. Full tanks and no rotation at launch save you from that worry.
And as for less mass being easier to stabilize - can you balance a pencil on your finger? How 'bout a broomstick?

Comment: Re:Someone doesn't understand basic relativity (Score 0) 81

by drerwk (#48616933) Attached to: SpaceX To Attempt Falcon 9 Landing On Autonomous Spaceport Drone Ship

And I don't mean the speed of light kind.

At 14 stories tall and traveling upwards of 1300 m/s (nearly 1 mi/s), stabilizing the Falcon 9 first stage for reentry is like trying to balance a rubber broomstick on your hand in the middle of a wind storm.

EXACTLY the same as takeoff. NO difference.

Same amount of fuel? No, so not the same moments of inertia. During launch the engine is pushing in the direction of travel, during re-entry no. During launch, the aerodynamics include that nice fairing on the nose, which should be a bit less chaotic than coming engine first down. The period of 1300 m/s travel that you quote and compare to launch is not during launch (0 m/s) - it is probably closer to the period of maximum dynamic load and clearly during super sonic travel. The reverse part of that travel, the period of maximal dynamic load during re-entry in a non-aerodynamic configuration is rather more difficult than getting off the pad.

Comment: Re:The video game crash of 1983 (Score 1) 191

by drerwk (#48612753) Attached to: Apple Wins iTunes DRM Case
The crash happened across platforms, though I have a limited view of it - I co-wrote Repton for Sirius Software, available on Apple II, C-64, and Atari 400/800. Sirius went out of business because 20th Century Fox failed a promised payment of $20mil. But I also worked for Infocom around '85 - and they were also crushed - maybe due to being text based.

Comment: Re:Nothing? (Score 1) 429

by drerwk (#48335681) Attached to: Mathematical Proof That the Universe Could Come From Nothing

As long as there's no faster-than-light travel, "X happens before Y" is an invariant - it's true in all reference frames.

No. http://math.ucr.edu/home/baez/... and for the longer version http://en.wikipedia.org/wiki/L.... In these examples, the doors either close at the same time for the observer stationary with respect to the barn, or at different times for the observer running with the pole.

OK, sorry, should have said ""X doesn't happen after Y" is an invariant" (there don't exist reference frames such that X happens before Y in one frame and X happens after Y in another frame).

Again no. A running coming from the other direction would see the doors close in the other order. I think the AC parallel to this post explains it pretty well.

Comment: Re:Nothing? (Score 4, Informative) 429

by drerwk (#48334853) Attached to: Mathematical Proof That the Universe Could Come From Nothing

As long as there's no faster-than-light travel, "X happens before Y" is an invariant - it's true in all reference frames.

No. http://math.ucr.edu/home/baez/... and for the longer version http://en.wikipedia.org/wiki/L.... In these examples, the doors either close at the same time for the observer stationary with respect to the barn, or at different times for the observer running with the pole.

Comment: Re:Science is not about trust (Score 1) 460

by drerwk (#48020661) Attached to: Scientists Seen As Competent But Not Trusted By Americans
Always enjoy reading his lectures - thanks. Had the pleasure of hearing a couple as well.
Maybe I was not clear in my statement - the LHC itself is not so much an experiment as a source of high energy collisions - the experiments are the detectors placed in the beam line, and with respect to the detection of the Higgs, there are the two: http://en.wikipedia.org/wiki/A... http://en.wikipedia.org/wiki/C.... While they are similar in that they detect collisions and take careful account of the collision products they do so differently. So they are effectively in a position to reproduce each others results as they have done with the detection of the Higgs.

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