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# Electron

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## US government is now the biggest buyer of malware, Reuters reports

Original author:
Joshua Kopstein

The US government is waging electronic warfare on a vast scale — so large that it's causing a seismic shift in the unregulated grey markets where hackers and criminals buy and sell security exploits, Reuters reports.

Former White House cybersecurity advisors Howard Schmidt and Richard Clarke say this move to "offensive" cybersecurity has left US companies and average citizens vulnerable, because it relies on the government collecting and exploiting critical vulnerabilities that have not been revealed to software vendors or the public.

"If the US government knows of a vulnerability that can be exploited, under normal circumstances, its first obligation is to tell US users," Clarke told Reuters. "There is supposed to be some mechanism...

## Synthetic particles that flock like birds

A flock of starlings is called a murmuration.

Scientists have built a self-organizing system of synthetic particles that assemble into clusters in a way that mimics the complicated organization of flocks of birds or colonies of bacteria. The particles form a “living crystal” that moves, swirls, and adjusts to heal cracks.

Self-assembly is a common way to build materials. Often, individual building blocks stick together due to inherent attractions, like bases of DNA bonding to form a nanotube, proteins gathering to form a helical virus coat, or nanospheres gathering to form a photonic crystal.

But what draws flocks of starlings, schools of fish, or rafts of ants together? Flocking or schooling can be a social behavior. However, the similarities among these phenomena, regardless of the creatures involved, led NYU's Jérémie Palacci and his colleagues to wonder if an underlying physical principle could also govern the organization process.

## TEDxSalford - Jim Al-Khalili - Quantum Life: How Physics Can Revolutionise Biology

TEDxSalford - Jim Al-Khalili - Quantum Life: How Physics Can Revolutionise Biology

Jim Al-Khalili is a professor of physics, author and broadcaster based at the University of Surrey where he holds a chair in the Public Engagement in Science. He is active as a science communicator and has written a number of popular science books, between them translated into over twenty languages. He is a regular presenter of TV science documentaries, including the Bafta nominated Chemistry: A Volatile History, and presents the weekly Radio 4 programme, The Life Scientific. He is a recipient of the Royal Society Michael Faraday medal and the Institute of Physics Kelvin Medal. He has also presented Atom, a three-part series for BBC Four, The Secret Life of Chaos, and Science and Islam, covering the leap in scientific knowledge that took place in the Islamic world between the 8th and 14th centuries. He's also a regular on Radio 4 and on the BBC's Horizon programme. Credits: Camerawork: Nathan Rae & Team - nathanrae.co.uk Post production: Elliott Wragg - twitter.com Audio restoration : Jorge Polvorinos - jorgepolvorinos.wordpress.com Head of IT and Design Vlad Victor Jiman - twitter.com
From:
TEDxTalks
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434

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## Q: Is it possible for an artificial black hole to be created, or something that has the same effects? If so, how small could it be made?

Physicist: Not with any current, or remotely feasible technology.  The method in use by the universe today; get several Suns worth of mass into a big pile and wait, is a pretty effective way to create black holes.

In theory, all you need to do to create an artificial black hole (a “black faux”?) is to get a large amount of energy and matter into a very small volume.  The easiest method would probably be to use some kind of massive, super-duper-accelerators.  The problem is that black holes are dense, and the smaller and less massive they are the denser they need to be.

A black hole with the mass of the Earth would be so small you could lose it pretty easy.  Except for all the gravity.

But there are limits to how dense matter can get on its own.  The density of an atomic nucleus, where essentially all of the matter of an atom is concentrated, is about the highest density attainable by matter: about 1018 kg/m3, or about a thousand, million, million times denser than water.  This density is also the approximate density of neutron stars (which are basically giant atomic nuclei).

When a star runs out of fuel and collapses, this is the densest that it can get.  If a star has less than about 3 times as much mass as our Sun, then when it gets to this density it stops, and then hangs out forever.  If a star has more than 3 solar masses, then as it collapses, on it’s way to neutron-star-density, it becomes a black hole (a black hole with more mass needs less density).

The long-winded point is; in order to create a black hole smaller than 3 Suns (which would be what you’re looking for it you want to keep it around), it’s not a question of crushing stuff.  Instead you’d need to use energy, and the easiest way to get a bunch of energy into one place is to use kinetic energy.

There’s some disagreement about the minimum size that a black hole can be.  Without resorting to fairly exotic, “lot’s of extra dimensions” physics, the minimum size should be somewhere around $2\times 10^{-21}$ grams.  That seems small, but it’s very difficult (probably impossible) to get even that much mass/energy into a small enough region.  A black hole with this mass would be about 10-47 m across, which is way, way, way smaller than a single electron (about 10-15 m).  But unfortunately, a particle can’t be expected to concentrate energy in a region smaller than the particle itself.  So using whatever “ammo” you can get into a particle accelerator, you find that the energy requirements are a little steeper.

To merely say that you’d need to accelerate particles to nearly the speed of light doesn’t convey the stupefying magnitude of the amount of energy you’d need to get a collision capable of creating a black hole.  A pair of protons would need to have a “gamma” (a useful way to talk about ludicrously large speeds) of about 1040, or a pair of lead nuclei would need to have a gamma of about 1037, when they collide in order for a black hole to form.  This corresponds to the total energy of all the mass in a small mountain range.  For comparison, a nuclear weapon only releases the energy of several grams of matter.

CERN, or any other accelerator ever likely to be created, falls short in the sense that a salted slug in the ironman falls short.

There’s nothing else in the universe the behaves like a black hole.  They are deeply weird in a lot of ways.  But, a couple of the properties normally restricted to black holes can be simulated with other things.  There are “artificial black holes” created in laboratories to study Hawking radiation, but you’d never recognize them.  The experimental set up involves tubes of water, or laser beams, and lots of computers.  No gravity, no weird timespace stuff, nothin’.  If you were in the lab, you’d never know that black holes were being studied.

## Blasting the photoelectric effect out of the quantum realm with a very intense light source

In 1905, Albert Einstein showed that the photoelectric effect—the ability of metals to produce an electric current when exposed to light—could be explained if light is quantum, traveling in discrete bundles of energy. His model, the photon theory, won him the Nobel Prize in 1921, but it left us with an enigma: why does the classical model of electric fields yield correct experimental results for some systems, but fail so dramatically for the photoelectric effect? In other words, at what point does the quantum world begin and the classical world end?

By directing very intense light to a nanoscale needle-like tip, G. Herink, D. R. Solli, M. Gulde, and C. Ropers have bridged the gap between the quantum and classical views of the photoelectric effect. The sheer number of photons hitting the needle dwarf the number of electrons involved, which ensures that individual photon interactions do not dominate. Instead, they created a quasi-classical system in which the bulk electric field of all the photons influences individual electrons. This result shows why the classical and quantum views are correct in certain regimes, and hints at an entirely new way to manipulate electrons in nanoscale materials.

## TEDxWWF - Justin Hall-Tipping: The Power of the Simple Electron

TEDxWWF - Justin Hall-Tipping: The Power of the Simple Electron

Justin Hall-Tipping works on nano-energy startups - mastering the electron to create power. Some of our most serious planetary worries revolve around energy and power - controlling it, paying for it, and the consequences of burning it. Justin Hall-Tipping had an epiphany about the need for finding and harnessing new forms of energy after seeing footage of a chunk of ice the size of his home state (Connecticut) falling off Antarctica into the ocean. A longtime investor, he formed Nanoholdings to work closely with universities and labs who are studying new forms of nano-scale energy in the four sectors of the energy economy: generation, transmission, storage and conservation. In thespirit of ideas worth spreading, TEDx is a program of local, self-organized events that bring people together to share a TED-like experience. At a TEDx event, TEDTalks video and live speakers combine to spark deep discussion and connection in a small group. These local, self-organized events are branded TEDx, where x = independently organized TED event. The TED Conference provides general guidance for the TEDx program, but individual TEDx events are self-organized.* (*Subject to certain rules and regulations) www.tedxwwf.com
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TEDxTalks
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