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http://www.newscientist.com/article/dn20116-light-through-a-blocked-hole-plasmonics-is-the-answer.html " How would you react if a tiny hole in a piece of foil let through more light after you had covered it – or painted the foil a different colour? With surprise, probably, like the physicists who discovered that this is just what happens with some very small holes. Both findings could lead to light-based transistors and other components for high-speed optical computers. Conventional optics forbids light from passing through holes that are much smaller than its wavelength, which for visible light means less than around 400 nanometres wide. But in 1998, Thomas Ebbesen at the University of Strasbourg, France, reported that some wavelengths of visible light stream through holes in gold foil that are less than 300 nanometres wide. It turns out that this is due to ripples known as plasmons that are found on the surface of metals and formed by the oscillation of electrons."

The highest resolution picture of a sunspot to date (NST 2010) Detail from Sunflowers (Vincent Van Gogh 1888)

Apparently, there will be no unallocated IPv4 addresses by the end of next week. There is a countdown clock available on one ISP's site.

What is your views:)

Well, not quite, but it's a very novel application of robotics.

A new convenient way of storing hydrogen that appears to make it usable as a fuel in unmodified petrol engines!

You have two tirangles ABC and A'B'C' prove that 2*BC*B'C'>=AB*A'B'+CA*C'A' if the corner BAC=B'A'C'=60° This was one of the problems in our school math competition :)

When will we have the energy for interstellar travel?

We know that assuming P and not P implies Q. But if we affirm and deny the law of the excluded middle on one hand we seem to get (P or not P) implies not not Q which I assume in this mode we can just say reduces to Q. But using not(P or not ) implies not not Q, which I am not sure reduces to Q without bringing us to the question all over again, so to speak. Thoughts? Lewis Carroll question: For a modus ponens argument, 1. If A then B 2. A therefore 3. B. one of course has to prove 1 by saying 1. If C then D 2. C therefore 3. D, which leads to an infinite regress...solution?

A nice article in the arxiv blog on this hot topic. What we call the Universe may have a similar role to that of our galaxy the 1920's.

Teleporting Energy And if so, how would this affect things like gravitational physics?

Howdy yall I just started calc 2 after not taking calc for about 3 years. I was given a problem that for the life of me I couldn't figure out. I used wolfram for the answer but I would appreciate it if someone could help me figure out how to do this problem. http://integrals.wolfram.com/index.jsp?expr=%28a%2Bbx^2%29%2FSqrt[3ax%2Bba^3]&random=false I know how to do most integration, but this one just blew me over. Thanks in advance.

So I have been browsing several math apps, most of which I have no use for (Riemann sum calculators for integrals-don't need, basic calc references-don't need). But I was thinking that a CAS would be useful, maybe for solving hard differential equations or nightmare integrals. I found one such CAS app. Any experience in this realm?

What are your favorite cartesian, polar, or parametric graphs?

Looks like current work is making it more and more clear that a lot of heredity is nothing to do with what genes you have. I recall some time back experiments that showed that what rat parents got taught influenced their offspring's abilities. May help to explain the 3 points rise in IQ values every decade? Standard genetics busted

Speed of a particle is 200 000m/s and has a wavelength of 150nm how much does it weight?

An experiment conducted by neuroscientist Dr. Michael Persinger: http://www.youtube.com/watch?v=nN3ggRgY7Ac&feature=related http://www.bbc.co.uk/science/horizon/2003/godonbrainqa.shtml http://www.independent.co.uk/arts-entertainment/dr-persingers-god-machine-1589465.html

http://www.sciencedaily.com/releases/2010/12/101202140622.htm "ScienceDaily (Dec. 2, 2010) — NASA-funded astrobiology research has changed the fundamental knowledge about what comprises all known life on Earth." "Researchers conducting tests in the harsh environment of Mono Lake in California have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The microorganism substitutes arsenic for phosphorus in its cell components."

A recent discussion involved the point that modern physics is very far removed from real-world applications. Here's an example of a possible application of some physics that I would not have anticipated (despite knowing enough to do so). A novel way of spying on rogue nuclear activity

"Hey, check this out." "What is it?" "See this cube?" He held up a cube approximately 6 inches on each edge. The outsides of each face were each composed of a different metal and divided into 9 smaller squares, the centers of each marked with a ink dot. The child took the large cube in his hands and looked at it with a confused expression. "What do I do with it?" "Rotate some sides." The inside mechanics of the cube allowed faces to be rotatable over the rest of the cube. A few minutes after, the cube was a multicolored jumble. All of the smaller cubes that made up the original had shifted into new chaotic locations. "Now put it back to normal." "You mean with all the colors on the same face again?" "Yes, its a puzzle." She moved the cube sides around in a sort of random manner. Eventually, one side was restored. She stared at the cube. To solve another side meant breaking up the first. It looked impossible to restore the cube. "I can't solve it." "Yes, have you heard of something known as entropy?" "It's something at the top of a forest." "No, that's canopy. Entropy is disorder. Like an unclean room. And there's a law that says you can't reverse entropy." "But I clean my room every week." "Yes, but when you clean your room, you use energy, right? And can you get back this energy?" "Yeah, I eat to get energy." "But what happens when food runs out?" "Food won't run out, we can keep growing it." "What if the sun ran out of fuel?" The child thought for a while. "I wouldn't be able to clean my room anymore?" He nodded. "Entropy is said to be unreversable. Like this cube. You can't put it back to normal." "So then what does the cube do?" He took back the cube and placed it inside a large slot under a computer and tapped on the keyboard. A tractor beam pulled the cube up and out of sight. A motor was heard running. Gears activated. The cube fell back to the ground. Solved. Back to normal. "You reversed entropy?" "Not quite. I needed a machine to solve it and that used too much energy." "Is there a way to reverse entropy?" He always loved to debunk beliefs of other scientists. But first he would always tell his daughter about it in his lab. She would invariably tell her science teacher. She would get sent to the principal's office for her "insubordination", and he would get called to the school to attend a conference. With amusement, he would introduce whatever breakthrough he'd made to the teachers. They would usually ignore it, but they couldn't deny the validity of his research after reading a published article he wrote. He despised how the education system worked, how it would convince kids that they knew everything at a young age by telling them about laws that had to be without providing proof. Like gravity. They used to teach about how gravity "always pulled stuff together". Then, with introduction of anti-gravitons, anti-gravity chambers could be constructed. Kids always believed they knew everything in the fall, and learned they knew nothing in the winter, and then believed they knew everything again in the spring. It wasn't right. So he made it a goal to insult the intelligence of the schools until the system was changed. "See this?" He removed a much smaller jumbled cube from his pocket. It was covered by stickers and made of plastic, but other than that, it was an exact replica. It spun much more easily due to its small size, but it was still heavy. The child spun a few sides and tried to solve the cube. It was futile. One completed side appeared, but the rest was in total disorder. "I can't solve it." "But suppose a human could solve it without using too much energy. Just thinking and moving sides." "Entropy reversal?" "Yes." -- The phone rang. "Hello?" A recording played, the same familiar recording, all it said was his child had been sent to the principal's office for saying a teacher was wrong. He hung up and drove to the school. The path was as memorable as morning activities. He'd been through the routine many times, probably 6 in the past 3 years, and knew exactly where to go. He marched into the office and exchanged greetings with the principal and his daughter. The principal motioned towards her. "So you told her that the second thermodynamics law is false?" "Yes, and it is. You have no proof for its validity and in a few days, I will put forth a fully working energy source that creates energy from nothing. So, see you then." He walked out of the office as the principal scowled. Insulting the principal probably wasn't the most productive way of changing the system, but it spared him from having to listen to "the school's point of view", and since word spread quickly through the school, his daughter had great respect in her peers. So it all balanced in the end. He drove back to his workplace to prepare to release a new product that would work as an energy source derived from thought. First he had to show the cube to his colleagues to have them write up an article about the counter example to thermodynamics. Writing prose had never been his strong suit. He arrived at the building where he was supposed to work, took the elevator up to the 6th floor, jogged down the corridor to the end, knocked on a door and entered. In an elongated and sing-song voice he announced, "I'm baaack." A suited man gazed up from some papers and recognition appeared on his face. "Oh, hey. It's been 8 months, hasn't it? How's everything going?" Due to a multitude of earth shattering breakthroughs, he was extremely valueable to the company at which he worked. To the point where he was on informal terms with his boss and could take as much leave as he needed. "A little over I think. Here, catch." "A colorful cube? I think these stickers should be more organized, and what is in it that makes it so heavy? I know you much better than to assume that for 8 months, all you have to show is a puzzle game." "You know the second law of thermodynamics?" "Yes, of course - wait, are you saying you disproved it?" "The cube was constructed in disarray. It is possible to get a computer to solve it, but even with the best program, I've doubts on energy conservation. However, if a human could be trained to solve these quickly, potential energy in the center is released and electricity is generated. And it is stored in, here give me the cube for a second, there." He threw the cube across the room and it slammed into a wall. Pieces flew apart but amongst the plastic was a shiny metal cube. He picked it up. "This is a battery. It used to be neutrally charged when the cube was made. But I was able to have it generate a small bit of energy as the cube it restored. When it becomes jumbled again, I was able to prevent the energy from disappearing with a sort of Maxwell's demon. You with me so far?" "I follow you, but can you prove that it works? I can't just take your word that that is a chargeable battery." "Okay, give me a few minutes." He produced a voltimeter from inside his sleeve and attached it to the metal cube. 0.0183 volts. He then gathered the plastic pieces and reconstructed the cube so that is was solvable using one turn. He solved it. The cube hit the wall again and shattered. The metal cube was reattached to the voltimeter and it read 0.0187. Energy from just solving it. "I think that turning that edge used more energy than what you just generated." "Yes, but suppose I constructed it in a more random pattern. One that optimized the cube's potential energy. The power generated increases exponentially based on complexity. Of course, it would take some time to solve. Using the same pattern over and over would burn parts of the battery making is unusable. If someone could be trained to solve these cubes quickly and efficiently, -" "Nobody could do something like that. There are what, 6 to the power of 54 possible positions? A little less, but nonetheless, still impossible." "Let's let the public be the judge of this, shall we? Here, take this cube, reverse engineer it, get a ghostwriter to write up an article about my entropy disproof. I'm going to mass produce these cubes and hire the public to solve them. They won't even know." -- He decided that the metal cubes inside were too valuable to fall into the hands of the public. They would have to be supervised. Better to just sell plastic shells and host competitions for people to solve the cubes quickly with competition cubes having the metal part within them. Speedcubing. It had a nice ring to it. He removed the metal cube from the schematics and ran his computer to loop a hundred times. Machines stirred. Some created plastic. Others morphed plastic into pieces. Others were to put them together. Yet more labelled them with stickers. A very efficient assembly line. And the power for them was routed from the National Research Association building, a few miles away. Nobody seemed to notice a few mysterious wires taking energy from that building. In about an hour, 100 cubes, all exactly identical and already solved were deposited onto the metal slide and fell into a basket. He waited. The door unlocked and his daughter entered. She threw down her bag and removed papers. She usually liked to work in her father's lab as there was a television and she could receive homework help at any time. "The teacher looked at me strange after the principal told him to ignore everything I said about entropy." "Of course. They don't believe it yet. But they'll find out soon. Take this bag of cubes. Sell them to your classmates. Tell them it's the new, what's the word? Fad? I think you'll be very popular at your school soon." "I already am popular." "You'll be much much more." ----------------------------- I know that the history of the rubiks cube is a bit different from this, but after watching a speedcubing contest, I decided to write about how they were mind control devices. It didn't work and I came up with this. Its different from the other writing pieces in that it's a short story format rather than article format. This way probably conveys the message better. For the record, I've no idea how to solve a cube.