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ewmayer 2013-10-17 20:28

[QUOTE=rogue;356469][URL="http://www.mentalfloss.com/article/52275/65-amazing-facts-will-blow-your-mind"]65 Amazing Facts That Will Blow Your Mind[/URL][/QUOTE]

[i]44. If you start counting at one and spell out the numbers as you go, you won't use the letter "A" until you reach 1,000.[/i]

Counting up: 2 = "tw[b]a[/b]in"

Counting down: -1 = "neg[b]a[/b]tive one"

"Four shalt thou not count, nor two, excepting thou then proceed to three. Five is right out."

xilman 2013-10-17 20:49

[QUOTE=ewmayer;356559][i]44. If you start counting at one and spell out the numbers as you go, you won't use the letter "A" until you reach 1,000.[/i]

Counting up: 2 = "tw[b]a[/b]in"

Counting down: -1 = "neg[b]a[/b]tive one"

"Four shalt thou not count, nor two, excepting thou then proceed to three. Five is right out."[/QUOTE]Possibly in American. In English you will reach "one hundred and one" much earlier.

ewmayer 2013-10-17 20:55

[QUOTE=xilman;356565]Possibly in American. In English you will reach "one hundred and one" much earlier.[/QUOTE]

You give us Yankees - whether of the Connecticutian variety or not - far too much credit, kind sir. IIRC the phrase "ne'er the twain shall meet" has a long history on both sides of the pond.

It is true that you Brits only need count down one to get an "a", though, via your well-known propensity to "naughtiness".

[i]54. In Spain, Mr. Clean is known as Don Limpio.[/i]

In English-speaking countries, isn't he the guy - wearing a toupee there, obviously - in the boner-pill adverts?

science_man_88 2013-10-23 20:48

[URL="http://news.yahoo.com/blogs/this-could-be-big-abc-news/terminator-plastic-polymer-heal-itself-014827978.html?vp=1"]“Terminator” Plastic Polymer Can Heal Itself[/URL]

[QUOTE]What if any plastic object you owned could heal itself if cracked or broken into two parts? No more emergency tire changes or water pipe fiascos; those pesky scenarios would resolve themselves.[/QUOTE]

Must be hydrophilic if you don't have to drain the water out first. Or that would be my guess.

rogue 2013-10-31 02:49

[URL="http://www.mnn.com/green-tech/research-innovations/stories/the-science-behind-some-of-your-favorite-candy"]The science behind some of your favorite candy[/URL]

[URL="http://www.wired.com/business/2013/10/free-thinkers/"]How a Radical New Teaching Method Could Unleash a Generation of Geniuses[/URL]

[URL="http://money.cnn.com/gallery/technology/2013/10/24/most-powerful-women-gaming.fortune/index.html"]The 10 most powerful women in gaming[/URL]

LaurV 2013-11-03 12:12

The eclipse LIVE! (for the next 2-3 hours, it already started)
[YOUTUBE]sJPhI6QcxPo[/YOUTUBE]

kladner 2013-11-03 14:22

The eclipse LIVE!
 
Very cool! Thanks!

only_human 2013-11-05 22:44

I love when science sounds like science fiction; not because it seems unlikely but rather because the mix of techniques and possibilities seems like a blend of poetry and fantasy:
[URL="http://physics.aps.org/articles/v6/121"]Viewpoint: A Single-Atom Optical Switch[/URL][QUOTE]Danny O’Shea and his colleagues at the Vienna University of Technology have taken an exciting step. Over the years, the team led by Arno Rauschenbeutel has pioneered techniques to fabricate “bottle” microresonators, which are bulge-shaped fibers made from heating and pulling conventional glass fibers. Light circulates around the bulge of the resonator because of total internal reflection, while also spiraling back and forth between two turning points at the narrow ends of the fiber. These turning points occur at “angular momentum barriers,” where all of the light’s forward momentum (along the axis) is converted to radial momentum (around the axis). The light is “sealed in” extremely well and can circulate tens of thousands of times around the bulge before being lost. The number of wavelengths traversed in one round trip around the device must be an integer number, leading to a set of sharply defined whispering gallery modes. The evanescent field leaks several hundred nanometers out of the glass and into the vacuum, providing an avenue for a nearby atom to talk to the cavity mode. The combination of long photon lifetime and tight spatial confinement can lead to strong coupling between a single atom and cavity photon, as the group demonstrated earlier this year [6].

In this most recent advancement [2], O’Shea and colleagues have used the resonator to create an “add-drop” filter regulated by a single atom. In this configuration, two waveguides, a “drop” fiber and “bus” fiber, are coupled evanescently to the bottle resonator, providing two different ports for light to enter or exit the resonator. By carefully positioning the fibers relative to the resonator, the waveguide couplings are critically tuned, such that an incoming photon in the bus fiber resonantly excites the cavity mode and leaves completely through the drop fiber (see Fig. 1, top). O’Shea et al. demonstrate that just a single atom coupled to the cavity can turn this switch from “on” to “off.” In the experiment, individual rubidium atoms from a nearby cold atom source occasionally fly into and out of the evanescent field of the resonator. During this time interval, the “fly-by” atom causes a large enough shift in the cavity resonance frequency that the critical coupling between the drop and bus fibers is destroyed. In this case, a photon will maintain its propagation in the bus (see Fig 1, bottom). The possibility of tuning the waveguide couplings allows the team to identify and attain the optimal point of operation of this atom-controlled optical switch.

The atom mostly acts in a classical capacity here, much like a small particle whose refractive index perturbs the light circulating in the cavity and modifies its frequency. However, the real interest in an atom-controlled switch is in the possibility of using the quantum nature of the atom. For example, the atom is a highly nonlinear optical element, as it can only scatter or switch single photons at a time. This is already inferred in the present experiment from the timing statistics of photons leaving the drop and bus fibers, and this feature could be exploited to implement quantum logic between single-photon pulses [8].

The authors also propose that it should be feasible to prepare the atom in a quantum superposition of internal states, only one of which can couple to the resonator. Then, the output direction of a photon initially sent through the bus fiber would become correlated with the internal state of the atom, leading to atom-photon entanglement. A promising feature of their results is the high contrast in transmission with/without the atom; for example, the amount of light exiting the drop fiber drops by a factor of 5 when the atom is present. Additionally, the incident light is recovered in the fibers with relatively little loss of about 20%. The absence of significant loss from beginning to end is crucial for the eventual implementation of more sophisticated quantum operations.

In the current experiment, a major limitation is that the atom is untrapped and instead passes through the evanescent field at random times. This has two important effects. First, the experiment can only be performed in short time intervals (here about 5 microseconds) when the atom is coupled to the cavity, and second, the position and coupling strength vary from shot to shot. Future versions of the experiment would benefit greatly by optically trapping cold atoms near the resonator, such as by integrating the nanofiber-based trapping technique pioneered by the same group [9]. If atoms can be trapped for a longer amount of time, then these photonic systems might be scaled up by building identical cavities and coupling the trapped atoms with photons traveling over a long-distance fiber.[/QUOTE]

ewmayer 2013-11-07 21:58

Right/Left-Brain/Creativity BS debunked
 
1 Attachment(s)
Right up there with the "women use many more words than men each day" BS, it seems:

Batalov 2013-11-07 22:18

[URL="http://en.wikipedia.org/wiki/Hemispherectomy"]Hemispherectomy[/URL]; [URL="http://www.nature.com/scientificamerican/journal/v298/n3/full/scientificamerican0308-104.html"]hundreds[/URL] of these were by now performed. On either half.
[QUOTE]...For example, one case followed a patient who had completed college, attended graduate school and scored above average on intelligence tests after undergoing this procedure at age 5.5. This patient eventually developed "superior language and intellectual abilities" despite the removal of the [B]left[/B] hemisphere, which contains the classical language zones.[/QUOTE]

LaurV 2013-11-08 03:22

Nice sharing, thanks.

Of course, I never believed that kind of BS telling you that you are using only 10% of your brain, and if you would be able to use all of it, then you will be kinda superman. I heard about a guy who, during some epileptic seizure, caught and bent a metal bar of 96 kg, which, in "normal" times he couldn't even lift up, or people talking 5 foreign languages after some head accident, and other stories like that, some of them may be real, having different scientific explanation, and there is also a lot of fabulation (why is this underlined red?) and rubbish there in the wild.

Why I don't believe those stories? Not because of James Randi, although I love him. But you know, those biological organisms are quite efficient thingies. If they are not efficient, they can't survive, adapt, and they will die. The human brain is, from all the biodiversity, the most inefficient organ. Don't laugh! This is serious! Physically speaking. Efficient, as defined in physics. The human brain produces a lot of heat, and no mechanical work. For some, it does not produce any work at all. But a lot of body energy is wasted in the heat produced by the brain (took by the blood and dissipated into the body, or radiated through the skull bones). The body does a lot of effort to cool the brain. Even when you are sleeping.

If we are using only 10% of our brain, why our body would be so stupid to cool down 90 percent of unused ballast? The biological organisms survive by adaptation, discarding unuseful things, and by gaining useful things, advantages, from the environment. Think about how first cells joined together, forming the first pluricellular organisms, for a higher efficiency in producing food, one cell catch the food, and supply some of it to the second cell, the second cell can't catch the food, but it has a small flagella to push the first cell around, toward the point where the food is. By this partnership, both cells get advantage over their colleagues. If some cells in the partnership are not needed anymore, like they lost the flagella or the ability to catch food, they are discarded. Think about your appendix. You don't use it, it gets smaller and smaller. In few hundred years we will have no appendix at all. It wastes energy to maintain unuseful body parts.

So, why our body would be so stupid to maintain 90 percent of inefficient, unuseful, high energy consumer, freaking brain? C'mon people, get real... Of course, it would be nice to be able to bend things and move them around without touching them, or to beat the gravity with the power of your mind, but till then, sit down and eat your porridge, human...


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