Beautiful Iranian blues and Jazz, both modern and traditional, posted by Kenan Malik on his blog.
Click below for more music.
https://kenanmalik.wordpress.com/2015/07/25/iranian-blues/
posted by f.sheikh
Iranian Blues-Music
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Monthly Archives: July 2015
Hackers Remotely Kill a Jeep on the Highway—With Me in It ( By Andy Greenberg)
I WAS DRIVING 70 mph on the edge of downtown St. Louis when the exploit began to take hold.
Though I hadn’t touched the dashboard, the vents in the Jeep Cherokee started blasting cold air at the maximum setting, chilling the sweat on my back through the in-seat climate control system. Next the radio switched to the local hip hop station and began blaring Skee-lo at full volume. I spun the control knob left and hit the power button, to no avail. Then the windshield wipers turned on, and wiper fluid blurred the glass.
As I tried to cope with all this, a picture of the two hackers performing these stunts appeared on the car’s digital display: Charlie Miller and Chris Valasek, wearing their trademark track suits. A nice touch, I thought.
The Jeep’s strange behavior wasn’t entirely unexpected. I’d come to St. Louis to be Miller and Valasek’s digital crash-test dummy, a willing subject on whom they could test the car-hacking research they’d been doing over the past year. The result of their work was a hacking technique—what the security industry calls a zero-day exploit—that can target Jeep Cherokees and give the attacker wireless control, via the Internet, to any of thousands of vehicles. Their code is an automaker’s nightmare: software that lets hackers send commands through the Jeep’s entertainment system to its dashboard functions, steering, brakes, and transmission, all from a laptop that may be across the country.
To better simulate the experience of driving a vehicle while it’s being hijacked by an invisible, virtual force, Miller and Valasek refused to tell me ahead of time what kinds of attacks they planned to launch from Miller’s laptop in his house 10 miles west. Instead, they merely assured me that they wouldn’t do anything life-threatening. Then they told me to drive the Jeep onto the highway. “Remember, Andy,” Miller had said through my iPhone’s speaker just before I pulled onto the Interstate 64 on-ramp, “no matter what happens, don’t panic.”1
http://www.wired.com/2015/07/hackers-remotely-kill-jeep-highway/?mbid=social_fb
Posted by f. sheikh
‘tragedy of the commons’ extra credit challenge By Dylan Selterman
Imagine you’re a student and your teacher poses this challenge to the entire class:
You can each earn some extra credit on your term paper. You get to choose whether you want 2 points added to your grade, or 6 points. But there’s a catch: if more than 10% of the class selects 6 points, then no one gets any points. All selections are anonymous, and the course grades are not curved.
I pose this exact challenge to students each semester in my social psychology course at the University of Maryland. This summer, one of my studentshappened to tweet about it, and his reaction went viral. This puzzle has resonated with millions of people around the globe—in the past week I’ve gotten responses from people in Poland, Spain, Italy, Croatia, New Zealand, and Paraguay, to name a few.
This exercise impels students to consider how their actions affect others, and vice versa. I’ve been giving it to students since 2008, and only one class has successfully mastered the challenge. In all other classes, more than 10 percent chose 6 points. Students’ temptation to reach for more points is very strong, and they often express exasperation when things don’t go their way. Last semester after I announced the results, one student threw up her hands and emphatically said, “If only everyone chose 2 points, we all would have gotten the points!”
Many professors in my field use versions of this exercise, which was first developed 25 years ago. I learned it as an undergraduate studying psychology under Steve Drigotas at Johns Hopkins. (I chose 2 points, and watched with extreme frustration as those points were lost when too many of my classmates choose 6 points.) As climate change and population growth threaten our resources, the experiment is more relevant now than ever.
This exercise illustrates the tragedy of the commons (or the “commons dilemma”), and is very similar to other exercises developed by behavioral scientists and game theorists (such as the “prisoner’s dilemma”). In cases like these, there’s a public resource that people can freely use to benefit themselves. In the classroom example it’s points, but in the real world the resource can be food, water, land, electricity, etc. If everyone is mindful about collective consumption and limits their personal use, the group will thrive. But if too many people behave selfishly (trying to maximize their own personal outcomes), then the group eventually suffers and everyone is left with nothing as the public resource is depleted.
It feels good to be cooperative both from a strategic and moral perspective. After all, if every student chose 2 points, everyone would get the extra credit, thus making it a rational choice. Furthermore, it’s the communal choice, based on an ethical imperative to do what’s best for others in the group. But many students choose the seemingly selfish option. Why? Perhaps to increase their own grades, or perhaps because they fear that they will be taken advantage of. No one wants to be the chump that chooses fewer points when they could have had more. The ideal scenario would be if everyone else was cooperative but you were selfish, thereby maximizing your reward while maintaining the health of the group. But it rarely works out that way, and people often find themselves in deadlocks of mistrust with others in their group.
posted by f.sheikh
Is Universe Eternal?
Worth reading article by Andrew Grant theorizing that universe may have no beginning and no end. ( f. Sheikh)
For nearly 140 years, scientists have tried to rule out the backward flow of time by way of nature’s preference for disorder. Left alone, nature transforms the neat into the messy, a one-way progression that many physicists have used to define time’s direction. But if nature prefers disorder now, it always has. The challenge is figuring out why the universe started out so orderly — thereby allowing disorder to grow and time to march forward — when the early universe should have been messy. Despite many proposals, physicists have not been able to agree on a satisfying explanation.
A new paper offers a solution. The secret ingredient, the authors say, is gravity. Using a simple simulation of gravitationally interacting particles, the researchers show that an orderly universe should always arise naturally at one point in time. From there, the universe branches in opposing temporal directions. Within each branch, time flows toward increasing disorder, essentially creating two futures that share one past. “It’s the only clear, simple idea that’s been put forward to explain the basis of the arrow of time,” says physicist Julian Barbour, a coauthor of the study published last October in Physical Review Letters.
It may be clear and simple, but it’s far from being the only idea attempting to explain the mystery of time’s arrow. Many scientists (and philosophers) over the decades have proposed ideas for reconciling nature’s time-reversible laws with time’s irreversible flow. Barbour and colleagues admit that the arrow of time issue is far from settled — there’s no guarantee that their simple simulation captures all the complexities of the universe we know. But their study offers an unusually elegant mechanism for explaining time’s arrow, along with some tantalizing implications. Attacking the arrow-of-time mystery along the lines Barbour and colleagues suggest may reveal that the universe is eternal.
Mixing marbles
Nobody knows exactly why time doesn’t flow backward. But most scientists have suspected that the explanation depends on the second law of thermodynamics, which describes nature’s fondness for messiness. Consider a jar containing 100 numbered marbles, 50 of them red and 50 blue. Someone with way too much free time then takes a picture of every possible arrangement of the marbles (yes, this would take far longer than a human lifetime) and creates a giant collage. Even though every photo depicts a different arrangement of numbered marbles, the vast majority of images would look very similar: a jumble of red and blue. Very few photos would have all the red marbles on one side of the jar and all the blue on the other. A photo picked at random would be far more likely to show a state of disorder than one of order.
Physicists in the 19th century recognized this propensity for disorder by thinking about the flow of heat in steam engines. When two containers of gas are exposed to each other, the faster-moving molecules of the higher-temperature container (think the blue marbles) tend to mix with the slower molecules (red marbles) of the cooler container. Eventually the combined contents of the containers will settle at an equilibrium temperature because a disordered state of blended hot and cold is most likely.
In the mid-19th century, physicists introduced the notion of entropy to quantify the disorder of a heat-shifting system. Austrian physicist Ludwig Boltzmann sharpened the definition by relating entropy to the number of ways that one could arrange microscopic components to produce an indistinguishable macroscopic state. The jar with segregated red and blue marbles, for example, has low entropy because only a few arrangements of the numbered marbles could produce that color pattern. Similarly, there are many combinations of speedy and sluggish molecules that will produce a gas at equilibrium temperature, the highest possible entropy. The fact that there are far more ways to achieve high entropy than low provides the foundation for the second law of thermodynamics: The entropy of a closed system tends to increase until reaching equilibrium, the maximum state of disorder.
The second law explains why cream easily mixes into coffee but doesn’t unmix, and why Humpty Dumpty won’t spontaneously reassemble after his fateful fall. Crucially, the second law also defines a thermodynamic arrow of time. The drive toward maximum entropy is an irreversible process in a universe governed by time-reversible physical laws. The second law suggests that time flows from past to present to future because the universe is progressing from an ordered low-entropy state to a disordered high-entropy one.