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Comment: Re:Science, bitches, that's *how* it works! (Score 2) 196

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.

Comment: Re:Science is not about trust (Score 3, Informative) 460

by drerwk (#48019371) Attached to: Scientists Seen As Competent But Not Trusted By Americans

Science is about reproducible results. Publish the details of your experiment, so I can perform your experiment (and variations on it) myself. Your claim is strengthened if I get the same results you do.

But I don't have a Large Hadron Collider! How am I supposed to reproduce this?

The fact is that many experiments are expensive to reproduce and will not be; and there are scientists who do poor work either intentionally or due to institutional reasons. The desire to do great science is only part of the motivation of a scientist; the desire to feed one's family can influence anyone thinking, as can the desire for fame, or other desires.
Addressing the LHC argument - The LHC requires thousands of scientists, the results will be examined to see if they match previous results at the appropriate energies, and it is worth noting that the LHC has detectors ATLAS and CMS which effectively check each others results regarding detection of the Higgs. And there are other detectors looking for new physics, that are not presently worth the cost of double coverage.

I suspect that there are backwaters of science, where someone may find gain in having published many papers, and have low risk of being caught because the value of the results is such that they will not be replicated; but when you cheat like Jan Hendrik Schön with results that would be quite valuable then you can expect work attempting to extend the experiment to be done, and when it fails the original work will be re-checked.

Comment: Re:Hmmm ... (Score 2) 356

by drerwk (#47984975) Attached to: Physicist Claims Black Holes Mathematically Don't Exist
Read the conclusion where the author directly addresses your concerns. But, I will also point out that at the stage of collapse the authors are talking about the star more closely resembles a neutron star rather than a hydrogen fusing star. Because a neutron star is supported by Pauli exclusion, it seems to me that the density may well be close to constant through out a majority of the star.

Comment: Re: Alright smart guy (Score 1) 504

by drerwk (#47963789) Attached to: Ask Slashdot: Is iOS 8 a Pig?
I use safari too - which is what is failing to load all kinds of things - I'm going to give tenfourfox a try. I mostly like to have a 'puter that the two year old can tear the keys off of and I don't get stressed out. But it would also be nice if the browser worked well enough for the seven year old to run his blog.

Comment: Re:Just do it. (Score 2) 234

by drerwk (#47939077) Attached to: Ask Slashdot: How To Pick Up Astronomy and Physics As an Adult?
To add to the Galaxy Zoo suggestion:
Have a look at this book: "Statistics, data mining and machine learning in astronomy" http://www.britastro.org/journ...
I have my BS in Physics, but I write software. I think it would be pretty hard at 10 hours a week to pick up the math of most of the advanced topics - even mechanics. But, learning statistics and data mining and having public access to data like the Sloan Survey would put you in the position to make real discoveries as an amateur. And, a modicum of competence in statistics and data mining may give you some good options for paying gigs.

If mathematically you end up with the wrong answer, try multiplying by the page number.

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