‘Unparticles’ May Hold The Key To Superconductivity, Say Physicists — The Physics arXiv Blog — Medium

‘Unparticles’ May Hold The Key To Superconductivity, Say Physicists — The Physics arXiv Blog — Medium: Georgi’s concept of unparticles comes about by conjecturing that some “stuff” may have mass, energy and momentum and yet also be scale invariant...

Physicists have long known that the behaviour of electrons in high-temperature superconductors is extremely complex...

What LeBlanc and Grushin show is that under certain conditions the interaction between these entities can become scale invariant and is therefore described by the physics of unparticles. In very simple terms, when that happens, material properties such as resistance no longer depend on the length scales involved. So if electrons move without resistance on a tiny scale, they should also move without resistance on much larger scales too. Hence the phenomenon of superconductivity.

The Astounding Link Between the P≠NP Problem and the Quantum Nature of Universe — The Physics arXiv Blog — Medium

The Astounding Link Between the P≠NP Problem and the Quantum Nature of Universe — The Physics arXiv Blog — Medium: ...He says the key is to think of Schrodinger’s cat as a problem of computational complexity theory...

...He says there is an implicit assumption when physicists say that Schrödinger’s equation can describe macroscopic systems. This assumption is that the equations can be solved in a reasonable amount of time to produce an answer...

If P ≠ NP and there is no efficient algorithm for solving Schrödinger’s equation, then there is only one way of finding a solution, which is a brute force search...

So the number of elementary operations needed to exactly solve this equation would be equal to 2^10^24...

...this time scale is considerably shorter than the Planck timescale, which is roughly equal to 10^-43 seconds.

Fire ants writhe to make unsinkable rafts - life - 26 November 2013 - New Scientist

Fire ants writhe to make unsinkable rafts - life - 26 November 2013 - New Scientist: A raft of live fire ants, on the other hand, resists and dissipates external forces equally well on all scales. The ants can act as tiny, resistive springs by flexing and extending their legs, and they break and reform connections with their neighbours to create a flow around external forces, like being prodded with sticks. Importantly, rafts of live ants are significantly more elastic than those made of flash-frozen dead ants.

What if quantum entanglement worked on the macroscopic level? | KurzweilAI

What if quantum entanglement worked on the macroscopic level? | KurzweilAI: ...now they have entangled two optic fibers, populated by 500 photons.

To do this, the team first created an entanglement between two fiber optics on a microscopic level before moving it to the macroscopic level. The entangled state survived the transition to a larger-scale world and the phenomenon could even be observed with the naked eye...

Simple Physics May Limit the Size of Leaves - ScienceNOW

Simple Physics May Limit the Size of Leaves - ScienceNOW: The researchers then considered how the total flow of sap and energy varies with leaf length. If the leaves are big, then resistance from the trunk limits the flow. In fact, making the leaves bigger than a certain maximum length yields no additional flow or benefit. On the other hand, if the leaves are very small, their resistance limits the flow. And if a leaf is shorter than a certain minimum length, then the sap would flow through the phloem more slowly than it could simply diffuse through the tree. At that point, the phloem plumbing would become useless.

In fact, these limits neatly fit the observed pattern of leaf sizes, the researchers report. And as tree height increases, the two limits converge and cross at roughly 100 meters: the height of the tallest angiosperms. That means trees taller than 100 meters simply could not produce leaves that obey both length limits, setting a limit for tree height, Jensen says.

Google Puts Its Virtual Brain Technology to Work

Google Puts Its Virtual Brain Technology to Work: ...Google engineers published results of an experiment that threw 10 million images grabbed from YouTube videos at their simulated brain cells, running 16,000 processors across a thousand computers for 10 days without pause.

"Most people keep their model in a single machine, but we wanted to experiment with very large neural networks," says Jeff Dean, an engineer helping lead the research at Google. "If you scale up both the size of the model and the amount of data you train it with, you can learn finer distinctions or more complex features."

New Theory Explains How Objective Reality Emerges from the Strange Underlying Quantum World | Guest Blog, Scientific American Blog Network

New Theory Explains How Objective Reality Emerges from the Strange Underlying Quantum World | Guest Blog, Scientific American Blog Network:  We consider how measurements work in the macroworld, finding that some quantum features are simply unobservable. Most remarkably, this approach shows that something called quantum nonlocality disappears for objects big enough to contain roughly the Avogadro number of atoms...
Our result derives from this concept of macroscopic observables being a kind of average. There is a limit to the number of quantum correlations each particle can have with another, which is referred to as the “monogamy” of quantum correlations. The concept is simple: if particles A and B exhibit correlations of the kind predicted in the EPR experiment then A and B can only have local and realistic correlations with other particles...
This monogamous behaviour extends to correlations between larger groups of quantum particles, which is the main idea behind our result. Imagine you are making a macroscopic measurement between two regions in space, A, containing quantum particles A1, A2, A3, etc., and B, containing B1, B2, B3, etc. The measurement samples all possible pairs. Due to monogamy, as you increase the number of particles, the overall strength of the correlations measured dilutes. For instance, AiBj may be strongly correlated but then Ai and any other B-particle exhibit only local realistic correlations (see figure). Analysing the statistics, we find that local realism emerges for macroscopic correlations without us needing to invoke any other mechanism.

Largest cosmic structures 'too big' for theories - space - 21 June 2011 - New Scientist

Largest cosmic structures 'too big' for theories: Shaun Thomas of University College London (UCL), and colleagues have found aggregations of galaxies stretching for more than 3 billion light years. The hyperclusters are not very sharply defined, with only a couple of per cent variation in density from place to place, but even that density contrast is twice what theory predicts.

[1104.2387] Liberating Efimov physics from three dimensions

[1104.2387] Liberating Efimov physics from three dimensions: When two particles attract via a resonant short-range interaction, three particles always form an infinite tower of bound states characterized by a discrete scaling symmetry. It has been considered that this Efimov effect exists only in three dimensions. Here we review how the Efimov physics can be liberated from three dimensions by considering two-body and three-body interactions in mixed dimensions and four-body interaction in one dimension. In such new systems, intriguing phenomena appear, such as confinement-induced Efimov effect, Bose-Fermi crossover in Efimov spectrum, and formation of interlayer Efimov trimers, and will be observable in ultracold atom experiments. This study significantly broadens our horizons of universal Efimov physics.

The Remarkable Pattern Of Neuronal Activity In The Brain - Technology Review

The Remarkable Pattern Of Neuronal Activity In The Brain - Technology Review: Ribeiro have carried out the first measurements of neuronal avalanche distribution in 14 rats carrying out certain tasks and throughout their full sleep-wake cycle.

Ribeiro say their results show clear evidence of criticality throughout this cycle (although the same rats show a different pattern when anaesthetised).

New model of plant structures reveals principles of supply networks | Santa Fe Institute

New model of plant structures reveals principles of supply networks | Santa Fe Institute: "SFI researchers Geoffrey West, James Brown, and Enquist have found remarkable fundamental processes across many systems and scales -- from animals to energy technologies to cities and companies -- that seem to arise from the form and limits of such distribution and supply networks.
The findings of the new model do a better job than previous models of matching empirical data for scaling relationships in a variety of trees -- including maple, oak, and pine -- which all exhibit important functional differences based on their anatomy."

Benford's Law -- from Wolfram MathWorld

Benford's Law -- from Wolfram MathWorld: Benford's law applies not only to scale-invariant data, but also to numbers chosen from a variety of different sources. Explaining this fact requires a more rigorous investigation of central limit-like theorems for the mantissas of random variables under multiplication. As the number of variables increases, the density function approaches that of the above logarithmic distribution. Hill (1998) rigorously demonstrated that the "distribution of distributions" given by random samples taken from a variety of different distributions is, in fact, Benford's law (Matthews).

One striking example of Benford's law is given by the 54 million real constants in Plouffe's "Inverse Symbolic Calculator" database, 30% of which begin with the digit 1. Taking data from several disparate sources, the table below shows the distribution of first digits as compiled by Benford (1938) in his original paper.

Curious mathematical law is rife in nature - physics-math - 14 October 2010 - New Scientist

Curious mathematical law is rife in nature: A subject of fascination to mathematicians, Benford's law states that for many sets of numbers, the first or "leading" digit of each number is not random. Instead, there is a 30.1 per cent chance that a number's leading digit is a 1. Progressively higher leading digits get increasingly unlikely, and a number has just a 4.6 per cent chance of beginning with a 9 (see diagram).

The law is named after physicist Frank Benford, who in 1938 showed that the trend appears in many number sets, from the surface area of rivers to baseball statistics to figures picked randomly from a newspaper. It later emerged that such distributions are "scale-invariant": if you convert the units of the numbers in the set, from metres to yards, say, the set will still conform to Benford's law.

Big or small, financial bubbles burst alike

The big crashes may hurt a lot more, but new analyses of “microbubbles” presented March 15 at a meeting of the American Physical Society find that the same mathematical laws underlying massive economic crises are also at work in tiny fluctuations that occur on the order of milliseconds.http://www.sciencenews.org/view/generic/id/57369/title/Big_or_small%2C_financial_bubbles_burst_alike_

Physicists observe quantum properties in the world of objects

“If I took a tuning fork and wanted to get it to the quantum ground state, I would have to cool it below 50 billionths of a kelvin,” he explains. “There is no technology that will allow you to do that, not now. But if you push the frequency of that tuning fork up” by orders of magnitude, “then you only have to cool it to 50 millionths of a degree above absolute zero."

http://www.sciencenews.org/view/generic/id/57385/title/Physicists_observe_quantum_properties_in_the_world_of_objects