Search found 942 matches

by Minerva
Fri Sep 23, 2011 9:53 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0955: "Neutrinos"
Replies: 159
Views: 45113

Re: 0955: "Neutrinos"

I like the alt-text. Resonant depolarisation measurements in LEP were so sensitive to geophysical movement (which would literally squash or move the accelerator by a miniscule amount) that it had to be corrected against (and could actually be used to measure) the tidal forces from the position of th...
by Minerva
Wed Sep 07, 2011 7:21 pm UTC
Forum: News & Articles
Topic: Supernova
Replies: 34
Views: 5977

Re: Supernova

I hope there is another supernova in our galaxy in my lifetime. They are such a remarkable sight that people have been getting excited about them, documenting them, drawing their positions and writing about them for about the last 2000 years, since well before the development of modern science.
by Minerva
Tue Sep 06, 2011 2:37 am UTC
Forum: Science
Topic: Cooling requirements for 50W carbon dioxide laser tube.
Replies: 6
Views: 6166

Re: Cooling requirements for 50W carbon dioxide laser tube.

What I'm looking at here is a slightly cheap and dirty Chinese-made laser cutter. http://www.hackmelbourne.org/wiki/images/e/e2/Image009.jpg There does not appear to be any flow switches, flow sensors or temperature sensors. I'm assuming that if there is no water flow, the output coupler and the ful...
by Minerva
Mon Sep 05, 2011 8:00 am UTC
Forum: Science
Topic: Cooling requirements for 50W carbon dioxide laser tube.
Replies: 6
Views: 6166

Cooling requirements for 50W carbon dioxide laser tube.

I'm currently working with a CO2 laser tube with an optical output of 50W in a laser engraver. It is your typical-looking large glass, water cooled, sealed CO2 laser tube. How critical is the water cooling with one of these tubes? What should the flow rate be? If the water flow is stopped, how quick...
by Minerva
Sat Sep 03, 2011 4:14 pm UTC
Forum: Serious Business
Topic: Does Santa Claus really not exist?
Replies: 90
Views: 17722

Re: Does Santa Claus really not exist?

I'm agnostic about Santa Claus in the same sense that I'm agnostic about the faeries at the bottom of the garden, or Thor, or Xenu, or the Easter Bunny.

Seriously, this has been done to death. Santa Claus is no different to any other god etc. for the purposes of this argument.
by Minerva
Wed Aug 24, 2011 7:01 am UTC
Forum: News & Articles
Topic: Lasers + Uranium= Fear
Replies: 14
Views: 4023

Re: Lasers + Uranium= Fear

It was just generally a response to the OP posted article, not a response to any particular person here.
by Minerva
Tue Aug 23, 2011 7:19 pm UTC
Forum: News & Articles
Topic: Lasers + Uranium= Fear
Replies: 14
Views: 4023

Re: Lasers + Uranium= Fear

Trying to pull the nuclear weapons proliferation argument when you're talking about nuclear energy or any nuclear fuel cycle facilities in the United States just does not make any sense. How does running nuclear power plants, or enrichment plants or fuel manufacturing, within the United States have ...
by Minerva
Fri Aug 12, 2011 5:04 pm UTC
Forum: News & Articles
Topic: Last Federal Helium Reserve, near Amarillo, is running out
Replies: 36
Views: 5781

Re: Last Federal Helium Reserve, near Amarillo, is running o

A big use is for hydrogen-fueled rocket engines. Helium is the only gas that does not solidify in the presence of liquid hydrogen. As such, it's the only material that can be used for purging the cryogenic plumbing used. Why purge? 1) A pre-burn purge is needed to remove all traces of atmospheric g...
by Minerva
Fri Aug 12, 2011 4:43 pm UTC
Forum: News & Articles
Topic: Swedish guy attempts to build fission reactor in his kitchen
Replies: 35
Views: 6784

Re: Swedish guy attempts to build fission reactor in his kit

Iulus Cofield wrote:Hey, I can think of two people who died doing cool but foolish things with radioactive materials


Just out of curiosity, who are these two people you had in mind?
by Minerva
Mon Aug 08, 2011 8:35 am UTC
Forum: News & Articles
Topic: Antimatter: We haz it.
Replies: 40
Views: 6105

Re: Antimatter: We haz it.

What is matter? Never mind. What is the mind? Doesn't matter Pamela satellite (an acronym for Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) Never mind the antimatter, who came up with that acronym?! I want that job. Physicists usually have their own dedicated in-house exp...
by Minerva
Sun Aug 07, 2011 3:10 am UTC
Forum: News & Articles
Topic: Rossi Cold Fusion Validated by Swedish Skeptic's Society
Replies: 77
Views: 22283

Re: Rossi Cold Fusion Validated by Swedish Skeptic's Society

Let's just say that they're not the first crackpots in the world who claim to have invented a magical machine that will solve all the world's energy problems forever. They're not the first to try and pull the "we can't show you any details about how it works because then Big Oil (or whatever) w...
by Minerva
Sat Aug 06, 2011 2:27 am UTC
Forum: News & Articles
Topic: Alternative therapy - Train tracks?
Replies: 22
Views: 3676

Re: Alternative therapy - Train tracks?

Placebo effects are very real, so if you cannot afford (or there aren't any) regular treatments, you're best off if you can find some irregular treatment that you believe works. If you can't afford regular treatments, then you probably can't afford "irregular treatments" either. People lo...
by Minerva
Fri Aug 05, 2011 4:41 pm UTC
Forum: News & Articles
Topic: Rossi Cold Fusion Validated by Swedish Skeptic's Society
Replies: 77
Views: 22283

Re: Rossi Cold Fusion Validated by Swedish Skeptic's Society

How reputable is the journal of nuclear physics? http://www.techeye.net/science/italian-scientists-claim-to-invent-cold-fusion However, Rossi and Focardi's paper on the nuclear reactor has been rejected by peer-reviewed journals. They published their paper in the Journal of Nuclear Physics , an onl...
by Minerva
Fri Aug 05, 2011 8:35 am UTC
Forum: News & Articles
Topic: Rossi Cold Fusion Validated by Swedish Skeptic's Society
Replies: 77
Views: 22283

Re: Rossi Cold Fusion Validated by Swedish Skeptic's Society

Also, it's funny how they claim to be liberating nuclear energy from nickel, an element which is essentially right at the peak of nuclear-binding stability, where it will be essentially impossible to get any nuclear binding energy liberated from it.
by Minerva
Fri Aug 05, 2011 8:32 am UTC
Forum: Science
Topic: KA's Q&A. This week: What exactly is a "dimension?"
Replies: 99
Views: 15916

Re: KA's Q&A. This week: E = mc^2 where m = 0?

E=mc2 doesn't mean that massless particles such as photons don't have any energy. But everything that has mass has some equivalent energy embodied in its mass.
by Minerva
Fri Aug 05, 2011 8:29 am UTC
Forum: News & Articles
Topic: Swedish guy attempts to build fission reactor in his kitchen
Replies: 35
Views: 6784

Re: Swedish guy attempts to build fission reactor in his kit

At best he has a small amount of mixed radium, americium and aluminium (or beryllium) containing materials, suitable as a very small neutron source. But this guy is sloppy, messy and incompetent, certainly a hell of a lot less competent than "radioactive boy scout" David Hahn was. If was t...
by Minerva
Fri Aug 05, 2011 8:24 am UTC
Forum: News & Articles
Topic: Alternative therapy - Train tracks?
Replies: 22
Views: 3676

Re: Alternative therapy - Train tracks?

emceng wrote:Ok, so this is obviously stupid and doesn't work.


But there is so much "alternative medicine" to which the above description applies.
by Minerva
Wed Aug 03, 2011 8:56 am UTC
Forum: News & Articles
Topic: Rossi Cold Fusion Validated by Swedish Skeptic's Society
Replies: 77
Views: 22283

Re: Rossi Cold Fusion Validated by Swedish Skeptic's Society

http://www.nyteknik.se/incoming/article3144960.ece/BINARY/Download+the+report+by+Kullander+and+Ess%C3%83%C2%A9n+(pdf The present test was done on a smaller device [5] than the 10 kW device that has been used earlier during the January press conference. One of the reasons for going to smaller dimensi...
by Minerva
Sat Jul 23, 2011 11:20 pm UTC
Forum: Science
Topic: Nuclear Fusion
Replies: 140
Views: 18881

Re: Nuclear Fusion

One of the goals of Project Gnome (http://en.wikipedia.org/wiki/Project_Gnome) was actually to generate electricity using the heat from nuclear explosions.
by Minerva
Wed Jul 20, 2011 12:25 pm UTC
Forum: News & Articles
Topic: Religious Medical Students Don't Want To Do Their Jobs
Replies: 732
Views: 49353

Re: Religious Medical Students Don't Want To Do Their Jobs

If a particular physician doesn't want to perform an abortion, and it's not urgently necessary to save the woman's life, and other physicians are accessible in the community (i.e. it's not a remote one-doctor town), and they're happy to refer the patient to a different physician, then I don't really...
by Minerva
Mon Jul 18, 2011 6:42 pm UTC
Forum: News & Articles
Topic: Electric car batteries getting a boost.
Replies: 64
Views: 6059

Re: Electric car batteries getting a boost.

Has this been published in peer-reviewed literature?

As always, something that goes to the mass media first instead of going to the peer-reviewed literature should send up alarm bells that it's crackpottery, just like car that runs on water, cold fusion etc.
by Minerva
Thu Jul 14, 2011 4:41 am UTC
Forum: Serious Business
Topic: Nuclear energy
Replies: 545
Views: 90781

Re: Nuclear energy

You won't get 1/3 energy conversion from D-T fusion. About 80% of the fusion energy, IIRC, is carried away by neutrons and is very difficult to recover. So if all global energy came from D-T fusion, and you multiply that 231 kg by as much as 5... In a lithium-blanket tokamak, the neutrons pass thro...
by Minerva
Tue Jul 12, 2011 7:20 pm UTC
Forum: Science
Topic: Schrodinger's Cat was just to illustrate a point, right?
Replies: 153
Views: 19327

Re: Schrodinger's Cat was just to illustrate a point, right?

To be honest, I think in the day and age where we actually build quantum computers and quantum key generators and nanoscale silicon cantilevers which are quantum harmonic oscillators, I think arguing about Schrodinger's Cat is a little bit redundant. When we build these systems, they really can be i...
by Minerva
Sun Jul 10, 2011 12:14 pm UTC
Forum: Science
Topic: Electronic equivalent of a syphon
Replies: 11
Views: 3855

Re: Electronic equivalent of a syphon

I would like something that does not conduct until some upper potential is reached but once activated continues to conduct until the potential drops below some other threshold. The first thought that popped into my head in response to your description was an SCR, but just like BJTs, SCRs are curren...
by Minerva
Tue Jul 05, 2011 3:59 am UTC
Forum: Science
Topic: Would you go blind if you became invisible?
Replies: 65
Views: 22732

Re: Would you go blind if you became invisible?

I will point out here that in Quake, the Ring of Shadows makes you invisible... except for your eyes. :)
by Minerva
Mon Jul 04, 2011 2:52 pm UTC
Forum: Science
Topic: Why do we measure half-life instead of just life?
Replies: 62
Views: 14335

Re: Why do we measure half-life instead of just life?

if you keep observing them, well you are feeding energy into the system in the form of high energy Gamma Rays. This is, in effect increasing temperature and pressure, so you are recreating Uranium 235 from fission fragments. So, in effect, finding more undecayed nucleotides than expected. Seemples....
by Minerva
Sat Jul 02, 2011 9:37 pm UTC
Forum: News & Articles
Topic: 8.8 Earthquake hits 250 miles from Tokyo
Replies: 471
Views: 76946

Re: 8.8 Earthquake hits 250 miles from Tokyo

Look, there's plenty of other articles that show it's bad and it's reached the U.S. No need to keep arguing about that one. And Dream is right. Just like would be preposterous to take always Daily Mail at face value, it would be preposterous to assume that every source Daily Mail quotes is personal...
by Minerva
Sat Jul 02, 2011 5:55 pm UTC
Forum: General
Topic: Uh-oh. It's a Youtube party and you're up next. What do you show 'em?
Replies: 2151
Views: 747964

Re: Something on Youtube

I think the early videos in this series have already been posted here, but anyhow... CallumCGLP's "Carl Sagan Tribute Series". http://www.youtube.com/watch?v=mpph1Bw0yXE&feature=channel_video_title If you haven't already watched these, you should watch every single one of the 15 videos...
by Minerva
Sat Jul 02, 2011 4:54 pm UTC
Forum: Science
Topic: Why do we measure half-life instead of just life?
Replies: 62
Views: 14335

Re: Why do we measure half-life instead of just life?

Minerva (back up towards the top of this thread) probably had the best explanation, written in impenetrable physics language. We aim to please. :) When I explain stuff, I tend to end up with explanations that are scientifically accurate, but maybe hard to completely understand for some people who d...
by Minerva
Thu Jun 30, 2011 10:32 am UTC
Forum: News & Articles
Topic: US nuke plants - how long can they go?
Replies: 7
Views: 1553

Re: US nuke plants - how long can they go?

http://theenergycollective.com/dan-yurman/59832/associated-press-nukes-nrc-reactor-safety "I had hoped for more insight from a prestigious organization such as AP. Their article entitled: “US nuke regulators weaken safety rules” is pretty sloppy and indicative of the fact AP failed to research ...
by Minerva
Thu Jun 30, 2011 3:24 am UTC
Forum: Science
Topic: Why do we measure half-life instead of just life?
Replies: 62
Views: 14335

Re: Why do we measure half-life instead of just life?

Surely after a period of one half-life for your substance, quite frequently there isn't *exactly* 50% left. It's statistically accurate if you've got a large number of atoms, but not if you've only got a small number of atoms. Atoms are very small, so usually when you've got stuff you've got a very...
by Minerva
Tue Jun 28, 2011 3:54 pm UTC
Forum: News & Articles
Topic: Krokodil; The Drug That Eats Junkies
Replies: 69
Views: 14141

Re: Krokodil; The Drug That Eats Junkies

I am willing to bet that the name crocodile does not come from the scaly skin it causes - that is probably just a post festum rationalisation and is only an issue with filthy processing. The clue is in the precursor: α-chlorocodide . I'm slightly dyslexic that way, so to me it's completely clear ho...
by Minerva
Mon Jun 27, 2011 2:21 pm UTC
Forum: Science
Topic: Why do we measure half-life instead of just life?
Replies: 62
Views: 14335

Re: Why do we measure half-life instead of just life?

It's stochastic. If you take a nucleus of a particular radionuclide and you watch it for one second, the probability that you will see nuclear decay within the span of one second (or whatever time interval you please) is some fixed constant probability ... but the actual time until decay is random ....
by Minerva
Sun Jun 26, 2011 5:40 pm UTC
Forum: News & Articles
Topic: Germany to Decommission All Nuclear Power Plants
Replies: 132
Views: 14498

Re: Germany to Decommission All Nuclear Power Plants

You're really not making any scientific sense here. If your scientific investigations don't prove anything, then they are inconclusive, not proof of a negative. The hypothesis is that known releases of radioactive material from Windscale may have contributed to rates of leukiemia and other cancers ...
by Minerva
Sun Jun 26, 2011 10:15 am UTC
Forum: News & Articles
Topic: Germany to Decommission All Nuclear Power Plants
Replies: 132
Views: 14498

Re: Germany to Decommission All Nuclear Power Plants

Cancer is a prevalent enough cause of death that even a miniscule shift in death rates, far below the error bars for any study, could cause dozens upon dozens of deaths over the years. And it would never be detectable, statistically or medically. If that's the way you want to think about it, then y...
by Minerva
Sat Jun 25, 2011 4:07 am UTC
Forum: Science
Topic: Quantum mechanics and life
Replies: 9
Views: 1673

Re: Quantum mechanics and life

This is one of your classical fallacies of hippy Deepak Chopra style new age pseudo-Quantum Mechanics.

A quantum-mechanical observation or measurement does not require a living thing or a consciousness.
by Minerva
Sat Jun 25, 2011 4:03 am UTC
Forum: News & Articles
Topic: Krokodil; The Drug That Eats Junkies
Replies: 69
Views: 14141

Re: Krokodil; The Drug That Eats Junkies

Codeine + SOCl 2 ---> α-Chlorocodide + HCl + SO 2 α-Chlorocodide + I 2 ---> 7,8-diiodo-α-Chlorocodide + HI ----> desomorphine (The latter step, the reduction, is done in one pot with the second reaction, with the HI formed in-situ from I 2 and red phosphorus, as with HI reduction of epedrine isomers...
by Minerva
Sat Jun 25, 2011 3:52 am UTC
Forum: News & Articles
Topic: Germany to Decommission All Nuclear Power Plants
Replies: 132
Views: 14498

Re: Germany to Decommission All Nuclear Power Plants

Cancer is a prevalent enough cause of death that even a miniscule shift in death rates, far below the error bars for any study, could cause dozens upon dozens of deaths over the years. And it would never be detectable, statistically or medically. If that's the way you want to think about it, then y...
by Minerva
Fri Jun 24, 2011 5:55 pm UTC
Forum: Serious Business
Topic: The Cleanest Energy
Replies: 42
Views: 7720

Re: The Cleanest Energy

Wouldn't connecting the bikes to each other make it more efficient? Like with horse power, it's not exactly 1 + 1 = 2...it kind of grows exponentially. If Alice generates 100 W, and Bob generates 100 W, and Carol generates 100 W, then the total power generated is 300 W. In this house we obey the la...
by Minerva
Fri Jun 24, 2011 5:35 pm UTC
Forum: News & Articles
Topic: Germany to Decommission All Nuclear Power Plants
Replies: 132
Views: 14498

Re: Germany to Decommission All Nuclear Power Plants

Deaths per TWh for nuclear: 2.9 (using only the Chernobyl numbers because that is all that we have data for) Of course, Chernobyl is completely, utterly irrelevant to any other nuclear power anywhere else ever in the history of the world, so that's not a truly accurate measurement of the average st...

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