“The cameras were turned toward Saturn and the sun so that the planet and rings are backlit. In addition to the visual splendor, this special, very-high-phase viewing geometry lets scientists study ring and atmosphere phenomena not easily seen at a lower phase.
Since images like this can only be taken while the sun is behind the planet, this beautiful view is all the more precious for its rarity. The last time Cassini captured a view like this was in Sept. 2006.”
Pac-Man is NP-hard, same as traveling salesman problem
An Italian researcher with a penchant for retro games — or perhaps just looking for an excuse to play games in the name of science! — has used computational complexity theory to decide, once and for all, just how hard video games are. In a truly epic undertaking, Giovanni Viglietta of the University of Pisa has worked out the theoretical difficulty of 13 old games, including Pac-Man, Doom, Lemmings,Prince of Persia, and Boulder Dash.
To begin with, Viglietta defines a few basic gameplay mechanics and sorts them into categories of complexity theory. Location traversal and single-use paths, ala Pac-Man, is NP-hard. Pressure plates, alaPrince of Persia or Portal, is PSPACE-hard if there are two pressure plates, and NP-hard if only one is required to open a door. In the case of switches, one switch is P-hard, two is NP-hard, and three or more is PSPACE-hard.
Viglietta then uses these characteristics to classify each of the 13 games. Boulder Dash, which involves traversing a map strewn with boulders, is NP-hard. Prince of Persia, thanks to its pressure plates, is PSPACE-complete. Doom, with its multiple switches, is PSPACE-hard (and Viglietta claims that most other FPSes and adventure games are the same).
Lemmings proved to be a bit harder to classify: If you just use Bashers and Miners, it is a traversal problem and NP-hard. Viglietta doesn’t try to tackle the complexity of using other types of lemming. A similar stretch allows him to classify StarCraft as NP-hard, where by each player is trying to produce the right units to allow him to traverse a certain path (to the enemy’s base).
If you’ve never heard of computational complexity theory, the best known example is the traveling salesman problem (TSP), which is NP-hard. In the TSP, you have to devise the most optimal route that visits a list of locations. This can be optimized as the shortest route, the fastest, the path of least resistance, and so on. Variants of the TSP are used to optimize transport systems, CPU designs, computeralgorithms, and more. PSPACE represents much more complex problems and puzzles that takes in games like Mahjong, Reversi, or Doom. If you want to know more, hit up Wikipedia— but be warned, complexity theory is a bit of a beast.
“I never am really satisfied that I understand anything; because, understand it well as I may, my comprehension can only be an infinitesimal fraction of all I want to understand about the many connections and relations which occur to me, how the matter in question was first thought of or arrived at…”
“The crescent Earth rises above the lunar horizon in this spectacular photograph taken from the Apollo 17 spacecraft in lunar orbit”
Collision and convergence in Truth and Beauty at the intersection of science and spirituality
On July 14, 1930, Albert Einstein welcomed into his home on the outskirts of Berlin the Indian philosopher Rabindranath Tagore. The two proceeded to have one of the most stimulating, intellectually riveting conversations in history, exploring the age-old friction between science and religion. Science and the Indian Tradition: When Einstein Met Tagore recounts the historic encounter, amidst a broader discussion of the intellectual renaissance that swept India in the early twentieth century, germinating a curious osmosis of Indian traditions and secular Western scientific doctrine.
The following excerpt from one of Einstein and Tagore’s conversations dances between previously examined definitions of science, beauty, consciousness, and philosophy in a masterful meditation on the most fundamental questions of human existence.
The DNA Replication Complex, an assembly of proteins that synthesizes new DNA before cell division. It consists of Helicase, Primase, Single-strand binding proteins, and DNA polymerase III. Because DNA strands can only be copied in one direction, the complex must pull out loops of one strand and replicate it in fragments. At this moment there are hundreds of trillions of these molecular machines in constant activity within your body.
Video Credit: Drew Barry
A new discovery for science and art: the cultural divide is all in the mind
Lucy Prebble’s latest play and a Barbican season on science and art show the barrier between the ‘two cultures’ is crumbling
This autumn a group of neuroscientists, medical students, doctors and psychiatrists got together at the University of Warwick to work out what we now know about the way the brain works. But they were not hunched over a pile of Cat scans, academic theses and medical notes. Instead they were looking at the theatrical work of Samuel Beckett. The great Irish playwright, some argued, understood and demonstrated patterns of human thought and emotion at a level of sophistication scientists have yet to reach. With the success this month of The Effect, Lucy Prebble’s play about the effect of chemicals on the brain, and the announcement of a new season of performance and debate about art and neuroscience at the Barbican in 2013, it looks as if the long struggle to break down barriers between science and creativity has entered a new phase. Not only is it conceded that scientific discoveries are fertile artistic territory, but scientists are being increasingly open about the value of the arts when fresh perspectives are required. “Our common sense is often our worst enemy,” said Marcus du Sautoy, the Oxford maths professor who will be appearing in the Barbican season. “After all, the discovery of anti-matter was only made because of the imagination of those scientists who said maybe there is something there when they kept coming up with all these strange negative solutions to their calculations.” (via A new discovery for science and art: the cultural divide is all in the mind | Culture | The Observer)
Complement with how to run right.
We essentially have our own, built-in, high-tech image stabilization system.
Stop that noise! Many creatures, such as human babies, chimpanzees, and chicks, react negatively to dissonance—harsh, unstable, grating sounds. Since the days of the ancient Greeks, scientists have wondered why the ear prefers harmony. Now, scientists suggest that the reason may go deeper than an aversion to the way clashing notes abrade auditory nerves; instead, it may lie in the very structure of the ear and brain, which are designed to respond to the elegantly spaced structure of a harmonious sound. “Over the past century, researchers have tried to relate the perception of dissonance to the underlying acoustics of the signals,” says psychoacoustician Marion Cousineau of the University of Montreal in Canada. In a musical chord, for example, several notes combine to produce a sound wave containing all of the individual frequencies of each tone. Specifically, the wave contains the base, or “fundamental,” frequency for each note plus multiples of that frequency known as harmonics. Upon reaching the ear, these frequencies are carried by the auditory nerve to the brain. If the chord is harmonic, or “consonant,” the notes are spaced neatly enough so that the individual fibers of the auditory nerve carry specific frequencies to the brain. By perceiving both the parts and the harmonious whole, the brain responds to what scientists call harmonicity. In a dissonant chord, however, some of the notes and their harmonics are so close together that two notes will stimulate the same set of auditory nerve fibers. This clash gives the sound a rough quality known as beating, in which the almost-equal frequencies interfere to create a warbling sound. Most researchers thought that phenomenon accounted for the unpleasantness of a dissonance. (via Human Brain Is Wired for Harmony | Wired Science | Wired.com)