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Why Standard Deviation Should Be Retired From Scientific Use

xPsi Heisenberg uncertainty (312 comments)

The celebrated Heisenberg uncertainty principle in quantum theory is based on statistical statements about the coupled standard deviations of position and momentum measurements (for example), not the mean deviation. The mean deviations are assumed to be zero since the means of the position and momentum distributions are exactly known for theoretical work. What matters are the fluctuations about the mean. In fairness, Taleb does allow physicists to keep using STD. But, quantum mechanics aside, it seems characterizing fluctuations about the mean, rather than fluctuations of the mean, is often an important measure depending on the nature of the investigation. Retiring the standard deviation seems a bit hasty.

about 10 months ago
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I'll keep my castle secure primarily with ...

xPsi Re:Electricity Pointy (828 comments)

We should make the distinction between bound electrons (in a pointy stick) and free electrons (electricity). With pointy sticks, electrostatics is a player, but I'm guessing it is primarily the inertia of the massive nuclei and Pauli exclusion that are really doing damage (and breaking bonds in your skin). With electricity, it is electrodynamics, not electrostatics, which is the culprit. You may be thinking of electrostatic discharge, which isn't usually what people mean by "electricity", but, as most of us on /. know, can still be quite effective for security (and should be in the poll). Ok, sorry. Just mod me both "making crap up" and Pedantic 2+3i.

more than 5 years ago
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To What Age Do You Expect To Live?

xPsi Re:Aubrey de Grey Interview? (575 comments)

What the heck ever happened to the interview with Aubrey de Grey? To answer the poll: I expect to live until I'm turned into gray goo.

Or did you mean. . . de Grey goo? [sound of horses neighing]

more than 5 years ago
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Opting Out Increases Spam?

xPsi Re:Well... (481 comments)

The submitter, J.L. Tympanum, is clearly some old timer's sockpuppet (low UID, only 3 unmodded non sequitur comments in 5 years, 2 quirky submissions including this one).

more than 5 years ago
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Colbert Wins Space Station Name Contest

xPsi NASA naming history (471 comments)

NASA has a long history of naming missions and modules after rather arbitrary, but dignified sounding, things. For example, the arts (Apollo Theater, Orson Welles' Mercury theater company, etc.) as well as pseudo-scientific things like signs of the zodiac and crypto-geographic places and cryptozoological creatures. Not to mention South American countries featured in drug-oriented movies, science fiction space ships, and even abstract contestants on a game show. "Colbert" seems pretty consistent with this non sequitur trend.

more than 5 years ago
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If We Have Free Will, Then So Do Electrons

xPsi Article summary (610 comments)

"In a whimsical abuse of pedigree leading to much undeserved press, two guys who apparently understand neither philosophy nor quantum mechanics mathematically connect two of those fields' major questions in a non-peer reviewed arXiv article and simultaneously solve humanity's deepest ontological questions using a translucent haze of logic."

more than 5 years ago
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Who Poses the Greatest Threat To Your Privacy?

xPsi 2nd person confusion (550 comments)

Based on the wording of the poll, I assumed the "you" in the question to be "me" and the "you/r" in the answers to be the pollster. Now that I understand the wording better, I want to make it perfectly clear I do not regard the slashdot staff to be the biggest threat to my privacy.

more than 5 years ago
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Physics Experiments To Inspire Undergraduates?

xPsi Bell's Inequality and entanglement (249 comments)

Here are a doublet of papers for an undergraduate laboratory demonstrating Bell's Inequality and and entangled photons. The whole apparatus (detailed in the second paper) is estimated to cost USD 15k circa 2002, so the optical elements have probably come down in price since then.

1. Entangled photons, nonlocality, and Bell inequalities in the undergraduate laboratory. [American Journal of Physics 70, 903 (2002)], Dietrich Dehlinger, MW Mitchell. http://arxiv.org/abs/quant-ph/0205171/

2. Entangled photon apparatus for the undergraduate laboratory. [American Journal of Physics 70, 898 (2002)], Dietrich Dehlinger, MW Mitchell. http://arxiv.org/abs/quant-ph/0205172/

more than 5 years ago
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A Quantitative Study of How Memes Spread

xPsi Parlor games are memes too I guess (219 comments)

I'm not sure why so much is being made of this '25 Random Things About Me' note on facebook. It is just a variation on an old parlor game that never really "came and went". Some people want to play, others don't. Yes, there are meme-y elements to virtually everything in a culture, but would an invitation to a kegger, superbowl party, LAN party, or a poker game be given such careful meme-y analysis? I'm not saying someone shouldn't analyze those things in this framework, but it seems this '25 Random Things About Me' note is being treated as a wild fad (some kind of canonical meme flash and burn) although it is really no different than some people at a large BBQ deciding to play poker while others play frisbee.

more than 5 years ago
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A Quantitative Study of How Memes Spread

xPsi Re:Actually, the REAL victims IMHO (219 comments)

Be advised you are following the same meme cliche cycle by complaining about it. For every annoying decaying, witless in-joke past its glory days, there's someone who has a tired argument to remind us how annoying, witless, and cliche the in-joke really is. And similarly, there's someone like me who will boorishly complain about the complaining about it. And so on. Culture's one big recursive clicheplex. I don't think we can help it.

more than 5 years ago
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Cuba Launches Own Linux Variation

xPsi Re:How did microsoft get around the embargo? (494 comments)

How did microsoft get around the embargo?

They aren't a company, man. They're their own frickn' weather system. They just need the coriolis force the tell them which way to spin.

more than 5 years ago
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The First Moon Map, and Not By Galileo

xPsi Re:Moon seems to have rotated in the past 400 year (82 comments)

The paper rotation idea is interesting, but before assuming the moon itself rotated with respect to the earth, wouldn't it just be easier to assume he sketched it at a different time of night at, at a different latitude, and/or different season then used "towards the ground as I'm looking at it" as down in the sketch? The moon's apparent orientation wrt one's line of sight on earth depends on all those things. Perhaps knowing where he sketched it and at what time of year, one could then figure out what time of night he did his work.

more than 5 years ago
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Miscalculation Invalidates LHC Safety Assurances

xPsi Re:Clarifications (684 comments)

The probability of creating a voracious black hole at the LHC is about the same as creating a voracious 1972 Cadillac at the LHC. Indeed, it is about as probable as creating a voracious black hole next to your head right now out of the vacuum. Such doomsday ideas were utterly fabricated nonsense forged in the minds of highly fringe and misguided people. The core ideas of your paper are interesting, but your work is better applied to things that really matter, not the pseudoscience of doomsday at supercolliders. Using the doomsday mania to sex up your work is fear mongering and borders on the unethical. Getting HIV from a handshake, however insanely unlikely, is a billion times more probable than destroying the earth from collisions at the LHC, but you don't seem to have used this example. Why not? Perhaps because it would be unethical to spread such nonsense?

more than 5 years ago
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We're In Danger of Losing Our Memories

xPsi Re:interesting idea (398 comments)

Archive.org is a good idea, but may be causing complacency. The problem is simple: a) they don't keep everything, and b) a lot of people seem to believe they do. That's an archival train wreck waiting to happen. They dynamically change the archive time window even for single sites, and even completely eliminate sites without notice. Besides, long after a site has been archived, a new system admin can block all archive requests (essentially forcing the removal of all archived versions of a site as if it didn't ever exist).

more than 5 years ago
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Are My Ideas Being Stolen? If So, What Then?

xPsi Public university customer is not the student (508 comments)

At a public university, the "customer" the university is servicing is not the student, but the state. A student is more an employee to the state than a customer of the university. Even for the ordinary student attending school without any special scholarships and who is not doing any explicit research under any state or federal grants, anywhere between 50-80% of the tuition to keep you in school is payed by taxpayers. That means your education is not for your benefit, but rather the state's. That's why most of the output you produce while in school legally belongs to "the system." The university's intellectual property policy usually reflects this. I think students tend to think of their public education as being mostly their own thing, so forget that they are ultimately accountable to the public. However unfair this may seem, it is pretty much the same anywhere in life. The professors, staff, and administrators are also under the same rules. In addition, in most non-academic private industries the rules are even more strict about whose ideas belong to whom and under under what conditions. All that said, there is a proper legal means for the university to partly own your ideas while still giving you formal credit. People can't just up and plagiarize or steal your ideas and claim them as their own novel work. If you suspect this is happening, you should raise bloody hell. There is a chain of ethical accountability that is maintained in an academic settings. Universities are better than most places in giving credit where credit is due because individualism is generally respected (this does frequently break down, though). This is in contrast to the private industry which doesn't honor that individualism so much.

more than 5 years ago
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At local midnight on the last day of the 2008 ...

xPsi Extremes (301 comments)

Last year I was flying over the Congo, this year I'm at home posting on slashdot. Weird. Go figure.

more than 5 years ago
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Banned Words List Carries Its First Emoticon

xPsi Go Magenta in 2009 (333 comments)

and try to reduce your cesium footprint. I know I'll do my part. Happy New Year.

more than 5 years ago
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Majel Roddenberry Dies At 76

xPsi Re:c'mon ppl,this is really sad,please hold the jo (356 comments)

Everyone mourns in different ways. Laugh, cry, tell jokes, be quiet, scream out, whatever you are compelled to do. However, I don't suggest judging the mourning styles of others.

more than 5 years ago
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Why Most Published Research Findings Are False

xPsi Not about being right (259 comments)

Science in general isn't about "publishing what is right" but rather creating a network of accountability in the form of methods, ideas, data, procedures, etc. so others can try and reproduce and critique the results. Even if the published results are shown to be incorrect by other studies, this does not mean the system is broken. The scientific process is an iterative, self correcting, one. However, if after many years and many studies, a particular field fails to converge on an accepted baseline conclusions, there is a good chance something is wrong (you may even be doing pseudoscience).

more than 6 years ago
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Any Suggestions For a Meaningful Geeky Wedding Band?

xPsi Charmonium (755 comments)

A charmonium ring would be pretty geeky and certainly impress the heck out of her. As the ground state of a charm and anticharm quark bound state, it is also amongst the most expensive materials on the planet, costing perhaps hundreds of millions of dollars and thousands of person-years to produce mere zeptomoles of the stuff. It not only has a nice moniker with the word "charm" in it, it is also a humble reminder we were once all part of a seething mass of quark-gluon plasma. Never mind the copious radiation that will be emitted as a ring-sized clump of the stuff rapidly decays on her finger. Ok, I'll shut up now. Iridium is definitely a good call.

more than 6 years ago

Submissions

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Life in 2048

xPsi xPsi writes  |  more than 6 years ago

xPsi writes "In the sprit of the recent slashdot discussion about the 1968 Mechanix Illustrated article '40 Years in the Future', augmenting a short thread on the subject, anyone else care to make good faith estimates of what life will be like in 2048? As these things go, the 1968 predictions seem quirky and quaint, occasionally non sequitur, with some modest measure of prescience. Although honest efforts at multi-decade futuristic predictions aren't so trendy today as they were 40 years ago, can we do any better? Besides, perhaps we slashdotters are best qualified to provide some media outlet in 2048 a public record of predictions to drag out and make fun of when the time comes."
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Should forum passwords be emailed in plain text?

xPsi xPsi writes  |  more than 6 years ago

ParanoidForumUser (851544) writes "Some popular forum packages (e.g. phpBB, etc.) have a default user registration process that involves sending a confirmation email to the user with the username and password in plain text in the body of the email (with a stark format like 'user: blah, password: foo'). Sometimes the registration process does not indicate the password you choose will sent in plain text nor does it encourage you to change the password after logging in the first time (where usually the password change itself is NOT emailed to you). Like many users, I have a library of different passwords of different levels of security I can use at will. Nevertheless, I find it very frustrating to select a carefully constructed password from my "good password" stack, thinking the site is secure, only to have it emailed to me in plain text anyway; while registering, I would certainly use a different password if I knew they were going to email it back to me. I'm not a security specialist, but this default user registration method strikes me as a generally bad security policy even for an internet forum since I (and I assumed most of the world) don't regard email as secure. When I've pointed out this issue (gently) to webmasters, the reaction has been strangely defensive and hostile. Here's one recent response from an irritated webmaster: 'So the emails should be mailed back encrypted? What are you talking about? Many sites do this without a problem. Especially when doing password recovery. I don't understand the problem.' So I ask the weighty expertise of slashdot: am I being overly cautious and old fashioned, or is sending plain text forum registration passwords in an email a security problem?"
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Parts of the galactic halo rotate "backwards&#

xPsi xPsi writes  |  more than 6 years ago

xPsi writes "Using data from the Sloan Digital Sky Survey, researchers have recently discovered that the galactic halo has two distinct components which rotate in opposite directions. From the article 'The main galactic disk, home to our sun, rotates at an average speed of 500,000 mph. Surrounding the disk is what's now called the inner halo. It orbits in the same direction at about 50,000 mph. The outer halo, a sparsely populated region, spins in the opposite direction at roughly 100,000 mph.' This discovery provides some insight into how galaxies, ours in particular, are formed."
Link to Original Source
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Brian May, rock legend, astrophysicist?

xPsi xPsi writes  |  more than 7 years ago

xPsi (851544) writes "Brian May, the guitarist for the legendary rock band Queen (age 60), finally decided to submit his Ph.D. thesis in astrophysics entitled 'Radial Velocities in the Zodiacal Dust Cloud.' From TFA: 'May was studying astrophysics at Imperial College when he formed Queen with singer Freddie Mercury and drummer Roger Taylor in 1970. He dropped his doctorate research into interstellar dust as the band met with increasing success.' Call me crazy, but 30-something years might be a record for a Ph.D. 'time to completion'; better late than never. And, hey, if this whole Rock-n-Roll thing doesn't pan out, at least he'll have something to fall back on...Congratulations soon-to-be Dr. May."
Link to Original Source

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