It’s a holiday miracle!
Without further ado, Tumblr for iPad is finally here. We hope you like it as much as we do.
(And don’t forget — Tumblr is awesome on your Android tablet too!)
In fluid dynamics, we like to classify flows as laminar—smooth and orderly—or turbulent—chaotic and seemingly random—but rarely is any given flow one or the other. Many flows start out laminar and then transition to turbulence. Often this is due to the introduction of a tiny perturbation which grows due to the flow’s instability and ultimately provokes transition. An instability can typically take more than one form in a given flow, based on the characteristic lengths, velocities, etc. of the flow, and we classify these as instability modes. In the case of the vertical rotating viscous liquid jet shown above, the rotation rate separates one mode (n) from another. As the mode and rotation rate increase, the shape assumed by the rotating liquid becomes more complicated. Within each of these columns, though, we can also observe the transition process. Key features are labeled in the still photograph of the n=4 mode shown below. Initially, the column is smooth and uniform, then small vertical striations appear, developing into sheets that wrap around the jet. But this shape is also unstable and a secondary instability forms on the liquid rim, which causes the formation of droplets that stretch outward on ligaments. Ultimately, these droplets will overcome the surface tension holding them to the jet and the flow will atomize. (Video and photo credits: J. P. Kubitschek and P. D. Weidman)
Chinese Researchers Achieve Quantum Teleportation at Macro Scale
So by entangling two photons, for instance, physicists have demonstrated the ability to transmit quantum information from one place to another by encoding it in these quantum states—influence one of the pair and a change can be measured in the other without any information actually passing between the two. Researchers have done this before, between photons, between ions, and even between a macroscopic object and a microscopic object.
But now Chinese researchers have, for the first time, achieved quantum teleportation between two macroscopic objects across nearly 500 feet using entangled photons…
The two bundles of rubidium atoms that served as sender and receiver are more or less analogs for what we hope will someday be our “quantum Internet”—a system of routers like the ones we have now that, instead of beaming information around a vast network of fiber optic wires, will send and receive information through entangled photons.
So in a way, this is like a first proof of concept, evidence that the idea works at least in the lab. Now all we have to do is figure out is how to build several of these in series so they can actually pass information from one to the other. To do that, we only have to somehow force these quantum states to exist for longer than the hundred microseconds or so that they last now before degrading. Sounds easy enough.
Maryam Mirzakhani: Why she kicks ass
- She is a mathematician.
- Professor of Mathematics (since September 1, 2008) at Stanford University.
- Her areas of research interest include: Teichmüller theory, hyperbolic geometry, ergodic theory, and symplectic geometry.
- She is an alumnus of National Organization for Development of Exceptional Talents (NODET) Tehran, Iran (Farzanegan highschool).
- She found international recognition as a brilliant teenager after receiving gold medals in both the International Mathematical Olympiad (Hong Kong 1994) in which she scored 41 out of 42 points, ranking her 23rd jointly with five other participants, and in the International Mathematical Olympiad (Canada 1995) with a perfect score of 42 out of 42 points, ranking her 1st jointly with 14 other participants.
- She obtained her BSc in Mathematics (1999) from the Sharif University of Technology.
- She holds a PhD from Harvard University (2004).
- She was a Clay Mathematics Institute Research Fellow and a professor at Princeton University.
- Some of her awards and honours include: IPM Fellowship The Institute for theoretical Physics and Mathematics, Tehran, Iran, 1995-1999; Merit fellowship Harvard University, 2003 and Harvard Junior Fellowship Harvard University, 2003.
Mathematics gets down to work in these talks, breathing life and logic into everyday problems. Prepare for math puzzlers both solved and unsolvable, and even some still waiting for solutions.
Ron Eglash: The fractals at the heart of African designs
When Ron Eglash first saw an aerial photo of an African village, he couldn’t rest until he knew — were the fractals in the layout of the village a coincidence, or were the forces of mathematics and culture colliding in unexpected ways? Here, he tells of his travels around the continent in search of an answer.
How big is infinity?
There are more whole numbers than there are even numbers … right? Actually, there aren’t. This TED-Ed talk makes it crystal clear why not, in a lesson on the infinite infinities and math’s unanswerable questions.
Arthur Benjamin does “Mathemagic”
A whole team of calculators is no match for Arthur Benjamin, as he does astounding mental math in the blink of an eye. But he’s not too worried you’ll steal his show, he says, and so he’s willing to share his secret in this mesmerizing talk.
Scott Rickard: The beautiful math behind the ugliest music
What makes a piece of music beautiful? Pattern and repetition, says Scott Rickard, as he sets out to create just the opposite – a piece mathematically calculated to be totally devoid of repetition. Listen if you dare.
Margaret Wertheim: The beautiful math of coral
The intricate forms of a coral reef can only be expressed through hyperbolic geometry — and the only way humans can model it is by crocheting! Margaret Wertheim and her crew of crotcheters engage the abstract and turn this traditional feminine handicraft into a large-scale environmental statement.
Benoit Mandelbrot: Fractals and the art of roughness
The world is based on roughness, explains legendary mathematician Benoit Mandelbrot. From cauliflower to the human lungs, he shows us objects that defy traditional measurements and consistently inspire curiosity and wonder.
Michael Mitchell: A clever way to estimate enormous numbers
Have you ever tried to guess how many pieces of candy there are in a jar? Physicist Enrico Fermi was very good at problems like these. A guide on how to make reasonable guesses on huge numbers by using the power of 10.
Geoffrey West: The surprising math of cities and corporations
Physicist Geoffrey West sees an urgent need for a scientific theory of cities, and he proposes we look to biology. Using the scaling principles that govern living things, he plots the way that everything – the good, the bad and the ugly – increases as cities grow.