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Submission Summary: 0 pending, 88 declined, 29 accepted (117 total, 24.79% accepted)

Space

Submission + - NASA to explore "secret layer" of the Sun (nasa.gov)

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "Early next year, NASA will launch the experimental telescope SUMI (Solar Ultraviolet Magnetograph Investigation) to study the transition region of the Sun. The transition region is about 5000km above the stellar surface and is where magnetic fields mysteriously accelerate the solar wind to a million mph. SUMI will use the technique of "Zeeman splitting." Although this technique has been used in the past to study thousands of sunspots, gas in the transition region produces spectral lines in the UV range that can't be seen with an Earth-based telescope."
Space

Submission + - Doughnut-shaped universe bites back (nature.com)

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "The once popular idea that the universe is small and finite is making a comeback. Many researchers thought that a 'wraparound' universe would mean that distant objects would be seen multiple times in the sky, but new research suggests '3-torus' (or 'doughnut universe') as well as other shapes could fit our actual observations."
Government

Submission + - Anti-Counterfeiting Trade Agreement (canada.com)

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "The Canadian government is secretly negotiating to join the U.S. and E.U. in an Anti-Counterfeiting Trade Agreement (ACTA). The agreement would give border guards the power to search your iPod and cellphone for illegal downloads, as well as force ISPs to hand over customer information without a warrant. According to David Fewer, staff counsel at the University of Ottawa's Canadian Internet Policy and Public Interest Clinic: "If Hollywood could order intellectual property laws for Christmas what would they look like? This is pretty close.""
Space

Submission + - The physics of whipped cream (nasa.gov)

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "An experiment on the Space Shuttle Columbia has been analyzing your ice cream sundae. Or, rather, it looked at the phenomenon of "shear thinning," which explains why whipped cream comes out of the can like a liquid, but sits atop your sundae like a solid. The experiment actually involved shear thinning of xenon, a substance used in ion rocket engines, but whipped cream tastes better."
The Internet

Submission + - NYC 911 to accept cellphone pictures

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "New York City is developing a plan to allow images to be sent to 911 emergency operators from cellphones. This will likely give emergency operators better information to pass along to responders. According to John A. Feinblatt, Mayor Michael Bloomberg's criminal justice coordinator, "The more information that the police have and the more quickly that they get it, the more likely that they are going to fight a crime.""
Books

Submission + - The Trouble with Physics

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "You've likely heard of Lee Smolin's book The Trouble with Physics. It has created a lot of controversy because it argues that string theory gets far too much attention and money, despite a complete lack of evidence. It accuses string theorists of groupthink.

First some basic background in case you haven't read Smolin's other books: Although Smolin has dabbled in string theory from time to time, he's a proponent of the alternative loop quantum gravity. Although irrelevant to this book review, he has also suggested that it is possible that universes reproduce via black holes, making them prone to pressure similar to natural selection (universes that produce a lot of black holes are more successful spawners than those that don't). Richard Dawkins, in The God Delusion, quotes Nobel-winner Murray Gell-Mann as once saying, "Smolin? Is he that young guy with those crazy ideas? He may not be wrong."

The Trouble with Physics is very unlike most pop-physics books not only in its criticism of string theory, but in its open adulation of Einstein and skepticism of the Copenhagen interpretation of quantum theory. Having said that, it does provide a very decent summary of 20th century physics (including string theory) for laypeople, not unlike more traditional pop-physics books (e.g. by Hawking and Greene).

The book's main criticisms of string theory are that it makes no testable predictions and that some things string theorists take for granted haven't been rigorously proven mathematically. Smolin is highly skeptical of many string theorists' reliance on the Anthropomorphic Principle.

The book becomes most interesting somewhere in the middle where he discuses truly controversial approaches to physics. This includes things like MOND, which, interestingly enough, Smolin is skeptical of.

In case you've forgotten your high-school physics, I'm going to use this paragraph to refresh your memory of special relativity to prepare you for the next couple paragraphs. The basic idea of special relativity is that the speed of light is constant. Pretend that I am shining a light at you while (A) standing still relative to you; (B) moving towards you at half the speed of light, and; (C) moving away from you at half the speed of light. In all three scenarios, I will accurately measure the light moving away from me at 3,000,000 km/s and you will accurately measure the light moving toward you at 3,000,000 km/s. To ensure this result, distances and times will have to be different for me than they are for you, except in case (A).

Now I'll quickly remind you of the Planck length: This is a theoretical limit on how small something can be. According to Smolin, all versions of quantum gravity seem to suggest the Planck length as a limit. But would observers moving relative to each other disagree about the Planck length?

I used to be a big fan of MOND (in a layperson sense) until Smolin introduced me to DSR (doubly special relativity) and DSR II. The basic idea is that it may be possible to modify the theories of relativity such that observers agree not only on a constant speed of light, but also on a constant Planck length. It's not unreasonable to guess that a modification of this sort could solve some of the same problems MOND does (e.g. explain astronomical observations without resorting to dark matter and dark energy). Furthermore, since DSR in its current incarnation predicts that more energetic photons are slightly faster than less energetic photons (only the speed of the least energetic photons is constant in DSR), it could also explain away, for example, inflation in the Big Bang model. (Immediately after the Big Bang, everything was hotter and more energetic, so the average speed of light would have been faster than it is now if DSR is correct.) Although I'm not qualified to judge the actual mathematics of such a theory, I find it very appealing for reasons of consilience.

I was slightly disappointed with the final chapters of Smolin's book since, despite an obvious effort to the contrary, it struck me as awfully bitter and reeked of sour grapes. Leaving physics in favor of sociology, he lambasted the current tenure and peer review systems (particularly in the United States) as favoring Master Craftspeople (like those scientists who developed the standard model of particle physics) over Seers (like Einstein, Bohr, and de Broglie) who look at the deep questions of physics that border on the philosophical rather than the latest technical problem. A few interesting things do emerge in these chapters. One such thing is that Smolin seems to have a soft spot for Paul Feyerabend as a philosopher of science (despite describing himself as a proud Popperazzo in an endnote). Another is that Smolin thinks a scientist who is hated by half his senior colleagues and loved by the other half is likely better than a scientist who is liked by all his senior colleagues.

I strongly recommend this book."
Biotech

Submission + - Sense of smell may be tied to quantum physics

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "A controversial theory that says our sense of smell is based not on the shape of the molecules that enter our nose but on their vibrations was given a boost recently when researchers at University College London determined that the quantum physics involved makes sense. The theory, which suggests electron tunneling initiates the smell signal being sent to the brain, could explain why very similarly shaped molecules have very different smells."
Biotech

Submission + - Stem cell therapy causes tumors

Submitted by
SpaceAdmiral
SpaceAdmiral writes: "Using human embryonic stem cells, researchers have cured a Parkinson's-like disease in rats. Unfortunately, the Parkinson's cure causes brain tumors. From the first article: "By definition, human embryonic stem cells have the almost mythical, immortal power to grow and divide indefinitely as they become the various tissues that make up the body. As a result, scientists have always known that any stem cell therapy could result in an uncontrolled growth of cells that could give rise to cancer. But that risk has remained largely theoretical since there have been few attempts to transplant tissues grown from stem cells into live animals.""

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