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Comment Awful, awful science reporting (Score 1) 236

Theorist with publications in dark matter here. This aspect of dark matter is not something new or a "mystery" but something that has been assumed for quite a long time. The alternative to this, "self interacting dark matter" is not entirely ruled out by observatins and explains some issues like the core-cusp problem but it's generally disfavored.

Comment Old news, probably not dark matter (Score 5, Informative) 66

This is really old news (at least in the particle physics cycle) and over a 100 papers have been written about this already. This is one of many papers that points out serious problems with a dark matter interpretation for this signal and here's a less technical blog post discussing the issues . I'm sick of pop-sci websites peddling stuff that particle physicists have already moved on from as the "latest exciting discovery"

Submission + - LUX experiment rules out low mass dark matter

thegreatemu writes: The LUX collaboration today released the first results using their huge liquid xenon detector to search for dark matter interactions in a live webcast from South Dakota's Sanford Lab. (Here's a copy of the talk and the corresponding paper (warning: PDFs)).
Their conclusion: they see no positive evidence for any kind of dark matter. Moreover, they have pretty conclusively (by a factor of 20!) ruled out conventional dark matter as a source of the low energy signals seen by many of their dark matter competitors (CDMS, CoGeNT, CRESST, and DAMA).

Submission + - Fitness bracelet with blood spectrometer (

disputationist writes: Airo Heath claims that their wristband AIRO will be able to measure calories and nutritional content of food ingest using an embedded spectrometer : "As your body breaks the food down, the sensor can detect the amount of light that passes through the blood based on green, red and infrared patterns." The press release does not say how precise the device is, but in a comment the CEO says it "compares favorably to nutrition labels for about 8/10 of the foods we’ve tested". Does this seem plausible for a $150 wristband?

Comment Higgs has been discovered!! (Score 2) 99

Both CMS and ATLAS are seeing bumps in certain Higgs channels around 125 GeV. While the bumps aren't big enough to be press-release worthy (2-3 sigma), a lot of particle physicists think that this is it. There will be an announcement on Dec 13th, and from now on it'll just be a matter of waiting till the bumps are 5 sigma and we can say for sure sure.

Comment Re:I also noticed a link (Score 2, Insightful) 289

A study, with so much bluster, and they studied just 94 people. Chuck a couple of zeros on that, then perhaps you have the makings of a worthwhile study and not just an anecdote.

Ugh. Not another math illiterate person complaining about the sample size. For the last time, your intuitive notions of statistics are worthless. The gamer study had a lot of people repeating this stupid objection too.

Comment Re:Correction : Average of 552 adults 19-90 (Score 1) 439

I am increasingly sick of these kinds of studies that use a sample pool so small as to be statistically irrelevant.

No, it's just that your intuitive ideas of what kind of sample size is statistically relevant are invalid. I am sick of how many people keep saying this even though it was addressed in an earlier post .

Also, the complaints about the sample size being restricted to Seattle are probably unwarranted. The sample size is large enough to provide a 95% confidence level for a reasonably small interval, and it would be highly unusual for such a general result that's true in Seattle to be significantly different for other cities.

It would imply that there was some confounding variable that's exclusive to Seattle that modifies the characteristics of gamers, which is an absurd assumption, and the only reason you would think so without other evidence is if you just didn't like the results of the study.

Comment Re:Yeah... (Score 1) 348

When people say evolution they don't just mean descent with modification, they mean the hypothesis that descent with modification (and other little things perhaps) is responsible for all the various species, and that this is how they descended from a common (and probably) single ancestor. It it this hypothesis that does not make (sufficiently) falsifiable predictions. Descent with variation is rather trivial and was known before and independent of Darwinian evolution. Anyone who breeds anything knows this.

Comment Poster doesn't understand TFA (Score 5, Informative) 348

The Maldacena duality can't be used to 'make predictions' with a string theory, its just a correspondence between a string theory and a conformal field theory. It's useful because sometimes calculations which are hard in a CFT can be made in the corresponding string theory which is sometimes easier (or vice versa). It cannot be used to support the physical validity of some string theory.

Comment Re:Sounds neat, but I'm confused... (Score 1) 220

Apparently the use of the term 'teleportation' is causing a lot of confusion. In QM, two particles that have identical states (quantum numbers) are considered indistinguishable; if they were switched, you wouldn't know. TFA describes a process that allows an entire state to be transferred instantaneously from one particle (or system) to another, and since in QM they are the same, the particle has been 'teleported'. There is nothing superluminal here, since before the state can be transferred you have to send some information across at kosher speeds.

Comment Re:A question that maybe someone might answer... (Score 2, Informative) 220

They know it was entangled because they prepared the state way. For example, if you have a spin zero particle that splits up into two particles, and you measure one as spin up, the other must be necessarily spin down, no matter how far away it is, because of the conservation of angular momentum. Or you can think of a neutral particle splitting into positive and negative ones. So I guess it is ultimately the consequence of some conservation law.

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Numeric stability is probably not all that important when you're guessing.