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las3rjock

47 karma · joined May 13, 2009

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las3rjock··on Let's Build a Superpower: see within and behind objects
Conventional holography proves this is possible. Portions of the image of a hologram can appear at points both closer and farther than the plane of the hologram itself. Furthermore, reflection holograms can be recorded in opaque media, so the parts of the hologram that form farther the hologram plane appear to be "inside" the hologram. See, for example, this photograph of one of the first three-dimensional holograms: http://en.wikipedia.org/wiki/File:Hologrammit.jpg . The hologram plane is demarcated by the sharp transition from red to black at the bottom, but the object in the hologram appear to be behind the hologram plane.
las3rjock··on Why I will never pursue cheating again
"Most of us who went to American grade schools can remember long hours of copying articles out of encyclopedias. 'The abode of the penguin is a hard and difficult one.' It was called doing research. Then in college we found that it was also called plagiarism."

-- Mary Claire van Leunen, "A Handbook for Scholars"

las3rjock··on In-N-Out Secret Menu Survival Guide
I forget when and why I started putting honey in the middle of KFC biscuits, but it's also surprisingly tasty.
las3rjock··on The State of Version Control: an Infographic
Down now for TOS violation, but +1 anyway for the effort. Any chance of summarizing the infographic textually somewhere?
las3rjock··on Bing sets the record straight on recent accusations
To crawl Google URLs of the form google.com?q=x would be to disregard http://www.google.com/robots.txt , which seems like bad netiquette to me.
las3rjock··on Bing sets the record straight on recent accusations
The page contents are being crawled and added to the index, but by Bing Toolbar users, not a computer program. I consider that to be an underhanded way to circumvent robots.txt, but others might not.
las3rjock··on Claim of Superconductivity Above 0C
Other claims that the author has previously made have allegedly been reproduced/explained by a group from Sharif University in Iran.
las3rjock··on Can you name the Programming Language if You Know The Creators?
15/19; missed JavaScript, Groovy, Scala, and Erlang.
las3rjock··on ITunes for Research Papers
If you're willing to shell out a few bucks, I highly recommend mekentosj's Papers over Mendeley. Among the free options, I prefer CiteULike (web-based; http://www.citeulike.org ) or Bibdesk (Mac OS X; http://bibdesk.sourceforge.net ).
las3rjock··on Math Books Organized by Area of Mathematics
Another notable book missing from that list is "Topology" by Munkres.
las3rjock··on Math Books Organized by Area of Mathematics
For real analysis, I'd recommend that you pick up a copy of "baby Rudin" regardless, but for learning real analysis, I'd recommend a book like "A First Course in Mathematical Analysis" by Burkill. Other viable options include "Calculus" by Spivak (it's really a book on real analysis at a level somewhere between a typical freshman calculus book and "baby Rudin"), "Real Mathematical Analysis" by Pugh, or "Yet Another Introduction to Analysis" by Bryant.
las3rjock··on Obama’s 2011 Budget Proposal, Department by Department (Infographic)
You're hardly the first person with this idea. There are many corporations already working in this sector--they're called government contractors.
las3rjock··on Obama’s 2011 Budget Proposal, Department by Department (Infographic)
I believe that the budget proposal on which this chart is based is only for the executive branch.
las3rjock··on Obama’s 2011 Budget Proposal, Department by Department (Infographic)
1. The Department of Energy appears in at least three places in the chart: once under "National defense", once under "General science", and once under "Energy". I assume the amount under national defense consists of the allocations for nuclear weapons stockpile stewardship and nuclear reactor production for the U.S. military.

I will agree that it is strange that the Federal Bureau of Investigation has been categorized as "National defense"; the rest of the Department of Justice seems to have been catergorized as "Administration".

2. One could categorize Medicare with Health, but one can already do that with the chart as shown by considering those two rectangles together. It is interesting to see that Medicare, by itself, has a larger allocation than everything else in the Department of Health and Human Services (and there are pieces in the Health rectangle that probably belong in the Medicare rectangle, e.g. "Grants to states for Medicaid" and "DoD Medicare-eligible retiree health care fund").

3. The Department of Veterans Affairs is a Cabinet-level department independent from the Department of Defense.

4. It looks like the Department of Justice and the Department of Treasury have been lumped together under "Administration".

I will agree that some aspects of this breakdown are strange, but I don't think it defeats the purpose of this chart.

las3rjock··on Ask HN: What's your favorite scientific paper?
A few of my favorites, chosen from computer science and from physics:

D. E. Knuth, "An empirical study of FORTRAN programs," Software: Practice and Experience, vol. 1, no. 2, pp. 105-133, 1971. http://dx.doi.org/10.1002/spe.4380010203

  A choice quote: "A first idea for obtaining 'typical' programs was to go to
  Stanford's Computation Center and rummage in the waste baskets and the recycling
  bins.  This gave results but showed immediately what should have been obvious:
  waste-baskets usually receive undebugged programs."
D. E. Knuth, "The errors of TeX," Software: Practice and Experience, vol. 19, no. 7, pp. 607-685, 1989. http://dx.doi.org/10.1002/spe.4380190702

  Knuth recounts and analyzes the process of developing the TeX computer typesetting
  system.
A. Einstein, "Zur elektrodynamik bewegter körper," Annalen der Physik, vol. 322, no. 10, pp. 891-921, 1905. http://dx.doi.org/10.1002/andp.19053221004

  Einstein's seminal paper "On the Electrodynamics of Moving Bodies" that proposed
  the theory of special relativity.  A good English translation is available online
  at http://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf
las3rjock··on Corruption in textbook-adoption proceedings: 'Judging Books by Their Covers'
I remember that chapter from Surely You're Joking, Mr. Feynman quite well. One of my favorite passages is the following, which is the source of the title of the chapter:

  We came to a certain book, part of a set of three supplementary books published by
  the same company, and they asked me what I thought about it.

  I said, "The book depository didn't send me that book, but the other two were nice."

  Someone tried repeating the question: "What do you think about that book?"

  "I said they didn't send me that one, so I don't have any judgment on it."

  The man from the book depository was there, and he said, "Excuse me; I can explain
  that. I didn't send it to you because that book hadn't been completed yet.
  There's a rule that you have to have every entry in by a certain time, and the
  publisher was a few days late with it. So it was sent to us with just the covers,
  and it's blank in between. The company sent a note excusing themselves and
  hoping they could have their set of three books considered, even though the third
  one would be late."

  It turned out that the blank book had a rating by some of the other members! They
  couldn't believe it was blank, because [the book] had a rating. In fact, the
  rating for the missing book was a little bit higher than for the two others. The
  fact that there was nothing in the book had nothing to do with the rating.
las3rjock··on Mendeley, the-Last.fm-of-research
Another Papers user here, and I also use a combination of CiteULike ( http://www.citeulike.org ) and Bibdesk ( http://bibdesk.sourceforge.net ). I find either system both easier and more powerful than Mendeley.
las3rjock··on Shazam: not magic after all
Here's an independent MATLAB implementation of the Shazam algorithm: http://labrosa.ee.columbia.edu/matlab/fingerprint/
las3rjock··on [dead]
Your answers to questions 1 and 2 contradict each other.
las3rjock··on UVa First-Year Student Computer Inventory: 1997-2008 Comparison
Am I the only person who looks at the first table and wonders who was the lone first-year student in 2008 who didn't own a computer?
las3rjock··on [dead]
The ad worked fine for me (Google Chrome 2.0.180.0 on Windows 7).
las3rjock··on Things Wolfram Alpha Does Better (And Vastly Different) Than Google
That query calculates "median planet volume / volume of a small grain of sand", as mentioned by the grandparent poster. I believe it is still an open question how to get Wolfram|Alpha to calculate "total planet volume / volume of a small grain of sand".
las3rjock··on Things Wolfram Alpha Does Better (And Vastly Different) Than Google
The query "total volume planets" yields a reasonable answer for that part of the problem, but I can't convince Wolfram|Alpha to divide it by "volume of a small grain of sand"... :-/
las3rjock··on Things Wolfram Alpha Does Better (And Vastly Different) Than Google
I was pretty sure I tried every permutation of the words "average," "height," and "human," but I guess I didn't. Bravo.
las3rjock··on Things Wolfram Alpha Does Better (And Vastly Different) Than Google
I've run into some weird bugs trying to perform calculations in Wolfram|Alpha. For example, I cannot come up with any query for the general question "human height vs Empire State Building" that works, even though the separate queries "height Empire State Building" and "height average male" return answers with units of length.