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It has been known for a century that electromagnetic fields can transport not only energy and linear momentum but also angular momentum. However, it was not until twenty years ago, with the discovery in laser optics of experimental techniques for the generation, detection and manipulation of photons in well-defined, pure orbital angular momentum (OAM) states, that twisted light and its pertinent optical vorticity and phase singularities began to come into widespread use in science and technology. We have now shown experimentally how OAM and vorticity can be readily imparted onto radio beams. Our results extend those of earlier experiments on angular momentum and vorticity in radio in that we used a single antenna and reflector to directly generate twisted radio beams and verified that their topological properties agree with theoretical predictions. This opens the possibility to work with photon OAM at frequencies low enough to allow the use of antennas and digital signal processing, thus enabling software controlled experimentation also with first-order quantities, and not only second (and higher) order quantities as in optics-type experiments. Since the OAM state space is infinite, our findings provide new tools for achieving high efficiency in radio communications and radar technology.

The Orbit Determination Program (ODP) of NASA's Jet Propulsion Laboratory, which was used in the data analysis, is based on an expression for the gravitational delay which differs from the standard formula; this difference is of second order in powers of $m$ -- the sun's gravitational radius -- but in Cassini's case it was much larger than the expected order of magnitude $m^2/b$, where $b$ is the ray's closest approach distance. Since the ODP does not account for any other second-order terms, it is necessary, also in view of future more accurate experiments, to systematically evaluate higher order corrections and to determine which terms are significant.

Kilometre-long pulses of light have been stored for over one second in a 0.1 mm cloud of ultracold atoms – before being revived and sent on their way. This latest demonstration of light storage using electromagnetically induced transparency (EIT) is the first to break the second barrier – using ultracold atoms and has the added bonus of preserving the quantum state of the incoming pulse. The physicists in the US who carried out the experiment say that the work could play a key role in quantum information technology.

a few megabits per second might someday get as much as 600 megabits per second, if not more. That could enable far more scientific payoff per mission in the long run.

new communication innovations such as disruption tolerant networking

one of the biggest communication revolutions will come from laser-driven optical communication

The interconnections fueled a cascading effect, with the failures coursing back and forth. A damaged node in the first network would pull down nodes in the second, which crashed nodes in the first, which brought down more in the second, and so on. And when they looked at data from a 2003 Italian power blackout, in which the electrical grid was linked to the computer network that controlled it, the patterns matched their models’ math.

After month of research and discovery, we’ve learned the following:1. Bitcoin is a technologically sound project.2. Bitcoin is unstoppable without end-user prosecution.3. Bitcoin is the most dangerous open-source project ever created.4. Bitcoin may be the most dangerous technological project since the internet itself.5. Bitcoin is a political statement by technotarians (technological libertarians).*6. Bitcoins will change the world unless governments ban them with harsh penalties.

The benefits of a currency like this:a) Your coins can’t be frozen (like a Paypal account can be)b) Your coins can’t be trackedc) Your coins can’t be taxedd) Transaction costs are extremely low (sorry credit card companies)

An individual with the name -- or perhaps handle -- of Satoshi Nakamoto first wrote about bitcoins in a paper called Bitcoin: A Peer-to-Peer Electronic Cash System.