Engineering Synthetic Chromophores to Improve Photosynthesis Through Using "Quantum Goldilocks Effect"

Nature has had billions of years to perfect photosynthesis, which directly or indirectly supports virtually all life on Earth. In that time, the process has achieved almost 100 percent efficiency in transporting the energy of sunlight from receptors to reaction centers where it can be harnessed -- a performance vastly better than even the best solar cells.

One way plants achieve this efficiency is by making use of the exotic effects of quantum mechanics -- effects sometimes known as "quantum weirdness." These effects, which include the ability of a particle to exist in more than one place at a time, have now been used by engineers at MIT to achieve a significant efficiency boost in a light-harvesting system.

Surprisingly, the MIT researchers achieved this new approach to solar energy not with high-tech materials or microchips -- but by using genetically engineered viruses.

This achievement in coupling quantum research and genetic manipulation, described this week in the journal Nature Materials, was the work of MIT professors Angela Belcher, an expert on engineering viruses to carry out energy-related tasks, and Seth Lloyd, an expert on quantum theory and its potential applications; research associate Heechul Park; and 14 collaborators at MIT and in Italy.

Lloyd, a professor of mechanical engineering, explains that in photosynthesis, a photon hits a receptor called a chromophore, which in turn produces an exciton -- a quantum particle of energy. This exciton jumps from one chromophore to another until it reaches a reaction center, where that energy is harnessed to build the molecules that support life.

But the hopping pathway is random and inefficient unless it takes advantage of quantum effects that allow it, in effect, to take multiple pathways at once and select the best ones, behaving more like a wave than a particle.

This efficient movement of excitons has one key requirement: The chromophores have to be arranged just right, with exactly the right amount of space between them. This, Lloyd explains, is known as the "Quantum Goldilocks Effect."

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Quantum Teleportation can Transfer two Properties With Fidelity

Suppose you see a beautiful table in a museum and you would like to have the same one at home. What could you do? One strategy is to accurately measure all its properties — its form (length, height and width) and its appearance (material and colour) — and then reproduce an identical copy for your living room. But this 'measure-and-reproduce' strategy would fail if the table were a quantum particle, such as a photon or an electron orbiting an atomic nucleus. The no-cloning theorem of quantum mechanics tells us that it is impossible to copy such a particle perfectly. On page 516 of this issue, Wang et al. show how to get around this apparent limitation of quantum physics. In a beautiful extension of previous experiments, they demonstrate how to transfer the values of two properties of a photon — the spin angular momentum (the direction of the photon's electric field, generally referred to as polarization) and the orbital angular momentum (which depends on the field distribution) — through quantum teleportation onto another photon.

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Quantum Speed Limit Found

University of California, Berkeley, scientists have proved a fundamental relationship between energy and time that sets a "quantum speed limit" on processes ranging from quantum computing and tunneling to optical switching.

The energy-time uncertainty relationship is the flip side of the Heisenberg uncertainty principle, which sets limits on how precisely you can measure position and speed, and has been the bedrock of quantum mechanics for nearly 100 years. It has become so well-known that it has infected literature and popular culture with the idea that the act of observing affects what we observe.

Not long after German physicist Werner Heisenberg, one of the pioneers of quantum mechanics, proposed his relationship between position and speed, other scientists deduced that energy and time were related in a similar way, implying limits on the speed with which systems can jump from one energy state to another. The most common application of the energy-time uncertainty relationship has been in understanding the decay of excited states of atoms, where the minimum time it takes for an atom to jump to its ground state and emit light is related to the uncertainty of the energy of the excited state.

"This is the first time the energy-time uncertainty principle has been put on a rigorous basis - our arguments don't appeal to experiment, but come directly from the structure of quantum mechanics," said chemical physicist K. Birgitta Whaley, director of the Berkeley Quantum Information and Computation Center and a UC Berkeley professor of chemistry. "Before, the principle was just kind of thrown into the theory of quantum mechanics."

The new derivation of the energy-time uncertainty has application for any measurement involving time, she said, particularly in estimating the speed with which certain quantum processes - such as calculations in a quantum computer - will occur.

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Extraordinary Claim With a Dash of Hype: The Quantum Experiment That Simulates A Time Machine

Physicists have simulated a photon interacting with an older version of itself in an experiment that could help reconcile quantum mechanics and relativity

One of the curiosities of general relativity is that it seems to allow time travel. Various physicists have discovered solutions to Einstein’s field equations that contain loops that return to the same point in space and time. Physicists call them closed time-like curves.

At first glance, these kinds of time machines seem to lead to all kinds of problems, such as the grandfather paradox. This is where somebody travels back in time and kills their grandfather meaning they could never have been born and so could not have gone back to kill the grandfather.

That’s just bizarre so physicists have attempted to find ways to prevent these paradoxes. In the early 90s, for example, cosmologists showed that a billiard ball entering a wormhole that leads to a closed time-like curve must always meet its older self coming out of the wormhole. What’s more, the resulting collision always prevents the ball entering the wormhole in the first place. In other words, the billiard ball would simply bounce off the entrance to a closed time-like curve.

So much for classical objects and time travel. But what would happen if a quantum particle entered a closed time-like curve? In the early 90s, the physicist David Deutsch showed that not only is this possible but that it can only happen in a way that does not allow superluminal signalling. So quantum mechanics plays havoc with causality but in a way that is consistent with relativity and so prevents grandfather-type paradoxes.

Deutsch’s result has extraordinary implications. It implies that closed time-like curves can be used to solve NP-complete problems in polynomial time and to violate Heisenberg’s uncertainty principle.

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Can Glancing Blows to Nuclei by Neutrinos Summon Particles From the Quantum Foam?

In what they call a “weird little corner” of the already weird world of neutrinos, physicists have found evidence that these tiny particles might be involved in a surprising reaction.

Neutrinos are famous for almost never interacting. As an example, ten trillion neutrinos pass through your hand every second, and fewer than one actually interacts with any of the atoms that make up your hand. However, when neutrinos do interact with another particle, it happens at very close distances and involves a high-momentum transfer.

And yet a new paper, published in Physical Review Letters this week, shows that neutrinos sometimes can also interact with a nucleus but leave it basically untouched – inflicting no more than a “glancing blow” – resulting in a particle being created out of a vacuum.

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Active Control Theory Applied to Quantum Based Technologies?

What does a 1980s experimental aircraft have to do with state-of-the art quantum technology? Lots, as shown by new research from the Quantum Control Laboratory at the University of Sydney, and published in Nature Physics today.

Over several years a team of scientists has taken inspiration from aerospace research and development programs to make unusually shaped experimental aircraft fly.

"It always amazed me that the X-29, an American airplane that was designed like a dart being thrown backwards, was able to fly. Achieving this, in 1984, came through major advances in a discipline called control engineering that were able to stabilise the airplane," said Associate Professor Michael Biercuk, from the School of Physics and director of the Quantum Control Laboratory.

"We became interested in how similar concepts could play a role in bringing quantum technologies to reality. If control engineering can turn an unstable dart into a high-performance fighter jet, it's pretty amazing to think what it can do for next-generation quantum technologies."

The result is that the researchers have been able to turn fragile quantum systems into useful pieces of advanced tech useful for everything from computation and communications to building specialised sensors for industry. The trick was figuring out how to protect them from their environments using control theory.

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Chinese Researchers Successfully "Teleport" Multiple Quantum Properties

Back in 1997, physicists performed an extraordinary experiment that will be forever remembered by researchers and Star Trek fans alike. In this demonstration, the team transported photons from one point in the universe to another without sending them through the space in between — the first successful teleportation in history.

Teleportation is the transfer of the information that describes one object to another object elsewhere in space. In effect, this second object takes on the identity of the first. A more precise description of the team’s experiment with photons is that they transferred the quantum information that describes the polarisation state of one photon to another photon.

Still impressive but not quite the teleportation of the entire photon, which has multiple quantum properties. All of these need to be teleported to recreate it exactly.

Since then, this kind of teleportation has become routine in quantum optics labs all over the world but always with the same limitation. All these experiments involve the transfer of a single quantum property. Nobody has ever found a way to transmit the multiple quantum properties of a single object at the same time and thereby truly teleport it.

Until now. Today, Xi-Lin Wang and buddies at the University of Science and Technology of China in Hefei say they have done just that. The team have worked out how to teleport two quantum properties of a single photon to another photon at the same time — the first time this has ever been done. The work is an important stepping stone towards the ultimate goal of teleporting complex objects such as atoms and small molecules in their entirety.

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Quantum Imaging With Undetected Photons

Quantum imaging with undetected photons

Authors:

Lemos et al

Abstract:

Information is central to quantum mechanics. In particular, quantum interference occurs only if there exists no information to distinguish between the superposed states. The mere possibility of obtaining information that could distinguish between overlapping states inhibits quantum interference. Here we introduce and experimentally demonstrate a quantum imaging concept based on induced coherence without induced emission. Our experiment uses two separate down-conversion nonlinear crystals (numbered NL1 and NL2), each illuminated by the same pump laser, creating one pair of photons (denoted idler and signal). If the photon pair is created in NL1, one photon (the idler) passes through the object to be imaged and is overlapped with the idler amplitude created in NL2, its source thus being undefined. Interference of the signal amplitudes coming from the two crystals then reveals the image of the object. The photons that pass through the imaged object (idler photons from NL1) are never detected, while we obtain images exclusively with the signal photons (from NL1 and NL2), which do not interact with the object. Our experiment is fundamentally different from previous quantum imaging techniques, such as interaction-free imaging or ghost imaging, because now the photons used to illuminate the object do not have to be detected at all and no coincidence detection is necessary. This enables the probe wavelength to be chosen in a range for which suitable detectors are not available. To illustrate this, we show images of objects that are either opaque or invisible to the detected photons. Our experiment is a prototype in quantum information—knowledge can be extracted by, and about, a photon that is never detected.

Quantum Hacking: The Latest Concern in Cybersecurity

Quantum hacking is the latest fear in the world of information security. Not so long ago, physicists were claiming that they could send information with perfect security using a technique known as quantum key distribution.

This uses the laws of quantum mechanics to guarantee perfectly secure communication. And perfectly secure communication is what you get, at least in theory.

The trouble is that in practice the equipment used to carry out quantum key distribution has a number of weaknesses that an eavesdropper can exploit to gain information about the messages being sent. Various groups have demonstrated how quantum hacking presents a real threat to “perfectly secure” communication.

So in the cat and mouse game of information security, physicists have been fighting back by designing equipment that is more secure. Today, Nitin Jain at the Max Planck Institute for the Science of Light in Erlangen, Germany, and a few pals show how the changes still leave the equipment open to attack but at the same time reveal how the next generation of quantum cryptography could be made better.

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New Technique Allows Quantum Computers to be Booted in 5 Minutes

Press the start button, switch on the monitor, grab a cup of coffee and off you go. That is pretty much how most us experience booting up a computer. But with a quantum computer the situation is very different. So far, researchers have had to spend hours making dozens of adjustments and fine calibrations in order to set up a chip with just five quantum bits so that it can be used for experimental work. (One quantum bit or 'qubit' is the quantum physical equivalent of a single bit in a conventional computer). Any small errors in the adjustment and calibration procedure and the chip would not work.

The problem is that, not unlike musical instruments, quantum computers react to small changes in the local environment. If, for example, it is a little warmer or a little colder or if the ambient air pressure is a little higher or a little lower than the day before then the complex network of qubits will no longer function – the computer is detuned and has to be readjusted before it can be used. 'Up until now, experimental quantum physicists have had to sit down each day and see how conditions have changed compared to the day before. They then had to remeasure each parameter and carefully recalibrate the chip,' explains Professor Wilhelm-Mauch, Professor for Theoretical Quantum and Solid-State Physics at Saarland University. Only a very small error rate of less than 0.1 percent is permissible when measuring ambient conditions. Frank Wilhelm-Mauch explains this sensitivity thus: 'That means that an error can occur in only one in a thousand measurements. If just two in a thousand measurements are in error, the software will be unable to correct for the errors and the quantum computer will not operate correctly.' With around 50 different parameters involved in the calibration process, one begins to get an idea of the sheer effort involved in calibrating a quantum computer.

Working together with his doctoral student, Wilhelm-Mauch began to consider a fundamentally new approach to the problem. 'We asked ourselves the question: Why is it necessary each and every day to understand how conditions differ from those of the day before?' The answer we eventually came up with was that it isn't necessary. What's important is that the setup procedure produces the right results. Why it produces the right results is not so relevant.' It was this pragmatic approach that underlay the work carried out by Wilhelm-Mauch and Egger. 'For the calibration procedure we used an algorithm from engineering mathematics, strictly speaking from the field of civil and structural engineering, as that's another area in which experiments are costly,' explains Professor Wilhelm-Mauch.

Using this technique, the two theoreticians were able to reduce the calibration error rate to below the required 0.1 percent threshold, while at the same time speeding up the calibration process from six hours to five minutes. The Saarbrücken methodology, which goes under the name Ad-HOC (Adaptive Hybrid Optimal Control), has now been subjected to rigorous testing by a group of experimental physicists from the University of California in Santa Barbara. Their experimental work is published in the issue of Physical Review Letters that also contains the Saarbrücken paper.

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Quibits With Error Correction

Even computers are error-prone. The slightest disturbances may alter saved information and falsify the results of calculations. To overcome these problems, computers use specific routines to continuously detect and correct errors. This also holds true for a future quantum computer, which will require procedures for error correction as well: "Quantum phenomena are extremely fragile and error-prone. Errors can spread rapidly and severely disturb the computer," says Thomas Monz, member of Rainer Blatt's research group at the Institute for Experimental Physics at the University of Innsbruck. Together with Markus Müller and Miguel Angel Martin-Delgado from the Department for Theoretical Physics at the Complutense University in Madrid, the physicists in Innsbruck developed a new quantum error-correcting method and tested it experimentally. "A quantum bit is extremely complex and cannot be simply copied. Moreover, errors in the microscopic quantum world are more manifold and harder to correct than in conventional computers," underlines Monz. "To detect and correct general errors in a quantum computer, we need highly sophisticated so-called quantum error-correcting codes." The topological code used for this current experiment was proposed by Martin-Delgado's research group in Madrid. It arranges the qubits on a two-dimensional lattice, where they can interact with the neighboring particles.

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OMG! Snowden Reveals ALL on NSA Developing Quantum Computers!!!

In room-size metal boxes ­secure against electromagnetic leaks, the National Security Agency is racing to build a computer that could break nearly every kind of encryption used to protect banking, medical, business and government records around the world.

According to documents provided by former NSA contractor Edward Snowden, the effort to build “a cryptologically useful quantum computer” — a machine exponentially faster than classical computers — is part of a $79.7 million research program titled “Penetrating Hard Targets.” Much of the work is hosted under classified contracts at a laboratory in College Park, Md.

[...]

“It seems improbable that the NSA could be that far ahead of the open world without anybody knowing it,” said Scott Aaronson, an associate professor of electrical engineering and computer science at the Massachusetts Institute of Technology.

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Actually, this is about as UNSURPRISING as anything Snowden has revealed.  The NSA, if they are doing their jobs the way they ought, really should be pursuing a quantum computer.  Likewise, they ought to be pursuing quantum cryptography (other side of their job is PROTECTION of American communications).  We know LANL produced a star config quantum encrypted network.  So, why in the world are we shocked the NSA is pursuing a quantum computer???  gah.

Likewise, given the prior knowledge of the Carnivore and ECHELON programs, why are we shocked the NSA has developed more capable skills?!  Naive or more likely false outrage is stupid.  Yes, false outrage.  Everyone spies on everyone and this is the world which spawned STUXNET, the "cyber superpower" which created it ought to be able to get into almost anything.  Thinking otherwise is disingenuous at best.

(PS no clemency.  The turkey, if he were a whistleblower, ought to have just revealed (with evidence) the actions of the NSA against US citizens.  He has revealed more than Manning did and Manning got 35 years)

Extraordinary Claim: Quantum Entanglement Appears to be Wormholes

Quantum entanglement, a perplexing phenomenon of quantum mechanics that Albert Einstein once referred to as "spooky action at a distance," could be even spookier than Einstein perceived.

Physicists at the University of Washington and Stony Brook University in New York believe the phenomenon might be intrinsically linked with wormholes, hypothetical features of space-time that in popular science fiction can provide a much-faster-than-light shortcut from one part of the universe to another.

But here's the catch: One couldn't actually travel, or even communicate, through these wormholes, said Andreas Karch, a UW physics professor.

Quantum entanglement occurs when a pair or a group of particles interact in ways that dictate that each particle's behavior is relative to the behavior of the others. In a pair of entangled particles, if one particle is observed to have a specific spin, for example, the other particle observed at the same time will have the opposite spin.

The "spooky" part is that, as research has confirmed, the relationship holds true no matter how far apart the particles are – across the room or across several galaxies. If the behavior of one particle changes, the behavior of both entangled particles changes simultaneously, no matter how far away they are.

Recent research indicated that the characteristics of a wormhole are the same as if two black holes were entangled, then pulled apart. Even if the black holes were on opposite sides of the universe, the wormhole would connect them.

Black holes, which can be as small as a single atom or many times larger than the sun, exist throughout the universe, but their gravitational pull is so strong that not even light can escape from them.

If two black holes were entangled, Karch said, a person outside the opening of one would not be able to see or communicate with someone just outside the opening of the other.

"The way you can communicate with each other is if you jump into your black hole, then the other person must jump into his black hole, and the interior world would be the same," he said.

The work demonstrates an equivalence between quantum mechanics, which deals with physical phenomena at very tiny scales, and classical geometry – "two different mathematical machineries to go after the same physical process," Karch said. The result is a tool scientists can use to develop broader understanding of entangled quantum systems.

link.

Where is the paper?!?! Must. Read.

Qubits Maintained at Room Temperature for 39 Minutes

A normally fragile quantum state has been shown to survive at room temperature for a world record 39 minutes, overcoming a key barrier towards building ultrafast quantum computers. The research, published in the journal Science, was led by Mike Thewalt (Simon Fraser University, Canada), with involvement from researchers at UCL and Oxford University, and material provided from collaborating institutes in Berlin.

In conventional computers data is stored as a string of 1s and 0s. In the experiment quantum bits of information, known as qubits, were put into a state of superposition in which they can be both 1s and 0 at the same time – enabling them to perform multiple calculations simultaneously. This is normally only possible at very low temperatures.

In the experiment the team used a system in which silicon is 'doped' with phosphorus atoms, and information is encoded in the phosphorus atoms' nuclei. Raising the temperature from -269 °C to 25 °C, the scientists discovered that the superposition states survived at this balmy temperature for 39 minutes. Outside of silicon the previous record for such a state's survival at room temperature was around two seconds.

"For a few years we've known that the nuclear spins for dopant atoms in silicon can be used as a long-lived memory for electron spins, a bit like a computer's hard disk," says UCL's John Morton (London Centre for Nanotechnology), a co-author of the research. "This work shows that removing the electron away from the dopant atom allows the information in the nuclear spin to live even longer – as long as three hours."

The team even found that they could manipulate the qubits as the temperature of the system rose, and that they were robust enough for this information to survive being 'refrozen' (the optical technique used to read the qubits only works at very low temperatures). 39 minutes may not sound particularly long, but since it only takes a tiny fraction of a second to run quantum computations by flipping the spin of phosphorus ions (electrically charged phosphorus atoms), many millions of operations could be carried out before a system like this decays.

"This opens up the possibility of truly long-term coherent information storage at room temperature," said Mike Thewalt (Simon Fraser University), the lead researcher in this study.

The team began with a sliver of silicon doped with small amounts of other elements, including phosphorus. They then encoded quantum information in the nuclei of the phosphorus atoms: each nucleus has an intrinsic quantum property called 'spin', which acts like a tiny bar magnet when placed in a magnetic field. Spins can be manipulated to point up (0), down (1), or any angle in between, representing a superposition of the two other states.

The team prepared their sample at -269 °C, just 4 degrees above absolute zero, and placed it in a magnetic field. They used additional magnetic field pulses to tilt the direction of the nuclear spin and create the superposition states. When the sample was held at this cryogenic temperature, the nuclear spins of about 37 per cent of the ions – a typical benchmark to measure quantum coherence – remained in their superposition state for three hours. The same fraction survived for 39 minutes when the temperature of the system was raised to 25 °C.

"These lifetimes are at least ten times longer than those measured in previous experiments," says Stephanie Simmons (University of Oxford), who collaborated in the study. "We've managed to identify a system that seems to have basically no noise. They're high-performance qubits."

There is still some work ahead before the team can carry out large-scale quantum computations. The nuclear spins of the 10 billion or so phosphorus ions used in this experiment were all placed in the same quantum state. To run calculations, however, physicists will need to place different qubits in different states.

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Perfect Bit Commitment Through Quantum Mechanics AND Relativity for 15 ms?

A breakthrough in quantum cryptography demonstrates that information can be encrypted and then decrypted with complete security using the combined power of quantum theory and relativity - allowing the sender to dictate the unveiling of coded information without any possibility of intrusion or manipulation.

Scientists sent encrypted data between pairs of sites in Geneva and Singapore, kept "perfectly secure" for fifteen milliseconds - putting into practice what cryptographers call a 'bit commitment' protocol, based on theoretical work by study co-author Dr Adrian Kent, from Cambridge's Department of Applied Mathematics and Theoretical Physics.

Researchers describe it as the first step towards impregnable information networks controlled by "the combined power of Einstein's relativity and quantum theory" which might one day, for example, revolutionise financial trading and other markets across the world.

'Bit commitment' is a mathematical version of a securely sealed envelope. Data are delivered from party A to party B in a locked state that cannot be changed once sent and can only be revealed when party A provides the key – with security guaranteed, even if either of the parties tries to cheat.

The technique could one day be used for everything from global financial trading to secure voting and even long-distance gambling, although researchers point out that this is the "very first step into new territory".

This is a significant breakthrough in the world of 'quantum cryptography' – one that was once believed to be impossible. The results are published in the journal Physical Review Letters.

"This is the first time perfectly secure bit commitment – relying on the laws of physics and nothing else – has been demonstrated," said Adrian Kent.

"It is immensely satisfying to see these theoretical ideas at last made practical thanks to the ingenuity of all the theorists and experimenters in this collaboration."

Any signal between Geneva and Singapore takes at least fifteen milliseconds – with a millisecond equal to a thousandth of a second. This blink-of-an-eye is long enough with current technology to allow data to be handed over encrypted at both sites, and later decrypted – with security "unconditionally guaranteed" by the laws of physics, say the team.

The researchers have exploited two different areas of physics: Einstein's special relativity – which interprets uniform motion between two objects moving at relative speeds – combined with the power of quantum theory, the new physics of the subatomic world that Einstein famously dismissed as "spooky".

Completely secure 'bit commitment' using quantum theory alone is known to be impossible, say researchers, and the "extra control" provided by relativity is crucial.

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Is Time an Artifact of Being the Restricted Observer?

Time is an emergent phenomenon that is a side effect of quantum entanglement, say physicists. And they have the first exprimental results to prove it

When the new ideas of quantum mechanics spread through science like wildfire in the first half of the 20th century, one of the first things physicists did was to apply them to gravity and general relativity. The result were not pretty.

It immediately became clear that these two foundations of modern physics were entirely incompatible. When physicists attempted to meld the approaches, the resulting equations were bedeviled with infinities making it impossible to make sense of the results.

Then in the mid-1960s, there was a breakthrough. The physicists John Wheeler and Bryce DeWitt successfully combined the previously incompatible ideas in a key result that has since become known as the Wheeler-DeWitt equation. This is important because it avoids the troublesome infinites—a huge advance.

But it didn’t take physicists long to realise that while the Wheeler-DeWitt equation solved one significant problem, it introduced another. The new problem was that time played no role in this equation. In effect, it says that nothing ever happens in the universe, a prediction that is clearly at odds with the observational evidence.

This conundrum, which physicists call ‘the problem of time’, has proved to be thorn in flesh of modern physicists, who have tried to ignore it but with little success.

Then in 1983, the theorists Don Page and William Wooters came up with a novel solution based on the quantum phenomenon of entanglement. This is the exotic property in which two quantum particles share the same existence, even though they are physically separated.

Entanglement is a deep and powerful link and Page and Wooters showed how it can be used to measure time. Their idea was that the way a pair of entangled particles evolve is a kind of clock that can be used to measure change.

But the results depend on how the observation is made. One way to do this is to compare the change in the entangled particles with an external clock that is entirely independent of the universe. This is equivalent to god-like observer outside the universe measuring the evolution of the particles using an external clock.

In this case, Page and Wooters showed that the particles would appear entirely unchanging—that time would not exist in this scenario.

But there is another way to do it that gives a different result. This is for an observer inside the universe to compare the evolution of the particles with the rest of the universe. In this case, the internal observer would see a change and this difference in the evolution of entangled particles compared with everything else is an important a measure of time.

This is an elegant and powerful idea. It suggests that time is an emergent phenomenon that comes about because of the nature of entanglement. And it exists only for observers inside the universe. Any god-like observer outside sees a static, unchanging universe, just as the Wheeler-DeWitt equations predict.

link.  paper link.

So, someone who is outside the universe, all observing, doesn't see squat.  um.  theological problem, maybe?

New Quantum Field Theory Simplifies, But Does Away With Locality and Unitarity

Physicists have discovered a jewel-like geometric object that dramatically simplifies calculations of particle interactions and challenges the notion that space and time are fundamental components of reality.

“This is completely new and very much simpler than anything that has been done before,” said Andrew Hodges, a mathematical physicist at Oxford University who has been following the work.

The revelation that particle interactions, the most basic events in nature, may be consequences of geometry significantly advances a decades-long effort to reformulate quantum field theory, the body of laws describing elementary particles and their interactions. Interactions that were previously calculated with mathematical formulas thousands of terms long can now be described by computing the volume of the corresponding jewel-like “amplituhedron,” which yields an equivalent one-term expression.

“The degree of efficiency is mind-boggling,” said Jacob Bourjaily, a theoretical physicist at Harvard University and one of the researchers who developed the new idea. “You can easily do, on paper, computations that were infeasible even with a computer before.”

The new geometric version of quantum field theory could also facilitate the search for a theory of quantum gravity that would seamlessly connect the large- and small-scale pictures of the universe. Attempts thus far to incorporate gravity into the laws of physics at the quantum scale have run up against nonsensical infinities and deep paradoxes. The amplituhedron, or a similar geometric object, could help by removing two deeply rooted principles of physics: locality and unitarity.

[...]

Locality is the notion that particles can interact only from adjoining positions in space and time. And unitarity holds that the probabilities of all possible outcomes of a quantum mechanical interaction must add up to one. The concepts are the central pillars of quantum field theory in its original form, but in certain situations involving gravity, both break down, suggesting neither is a fundamental aspect of nature.

In keeping with this idea, the new geometric approach to particle interactions removes locality and unitarity from its starting assumptions. The amplituhedron is not built out of space-time and probabilities; these properties merely arise as consequences of the jewel’s geometry. The usual picture of space and time, and particles moving around in them, is a construct.

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Do Blackholes Feed Off the Quantum Foam?

One of the more fascinating astrophysical discoveries in recent years is that almost all galaxies hide supermassive black holes at their cores. Indeed, astronomers believe that galaxies and black holes have a kind of symbiotic relationship so that one cannot form or grow without the other.

The evidence comes from observations of galaxies both near and far—almost all contain huge black holes.

But that raises an interesting question. We see the most distant galaxies as they were soon after the universe began. Some of these contain black holes that are a billion times more massive than the Sun but are themselves only a billion years old. The problem for astrophysicists is how these black holes could have grown so massive in such a short space of time.

Today, we get an answer from Marco Spaans at the University of Groningen in the Netherlands. He says that black holes can grow by feeding on the quantum black holes that leap in and out of existence at the smallest scale. These quantum black holes are part of the so-called quantum foam that physicists believe makes up the fabric of the Universe.

If Spaans is right, black holes grow by feeding on spacetime itself and their quantum feeding habits effectively solve the problem of how the biggest black holes become so massive, so quickly. “Supermassive black holes can acquire a lot of their mass through these quantum contributions over the life time of the universe,” he says.

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Three thoughts. 

If this is true, it has some wildly weird implications about matter and the universe. 

It also means you can do funny things with the quantum foam. Possibly technologically.  Almost bet that's the next big thing for physics circa 2050.

Black hole evaporations are going to be weirder still: all the other half of the virtual particle pairs are coming back.

Is Quantum Entanglement an Example of an Einstein-Rosen Bridge?

Are black holes surrounded by walls of fire? Does this imply that one (or more) of our most cherished physical principles—and here I’m talking about biggies like quantum theory, the conservation of information or Einstein’s equivalence principle—is wrong? Any may our savior come in the form of wormholes? These are the questions consuming some of the world’s foremost theoretical particle physicists as they argue about potential solutions to what has become known as the “black hole firewall” problem—perhaps the most important paradox in physics since Stephen Hawking proposed his first black hole information paradox nearly four decades ago.

[...]

The black hole firewall paradox has caused no small amount of wonder and confusion amongst particle physicists. It appears as though one of our core beliefs about the universe is wrong: Either particles can be promiscuously entangled, leading to quantum disaster (basically no one takes this option seriously; quantum theory and the no-promiscuous-entanglement rule are far too well supported by decades of experimental evidence), or information is not conserved (another non-starter), or black holes have firewalls (even Polchinski considers this a reductio ad absurdum), or… we just don’t fully understand what’s really going on.

And so in an effort to sort the mess out, physicists gathered this week at the Kavli Institute for Theoretical Physics at UCSB to talk over the options. (They’ve been doing a great job uploading videos of all the talks, so if you’re interested in watching smart folks try to hash out knotty thought experiments in near-real time, you can follow along at home.) One of the most intriguing possibilities for a solution comes from Juan Maldacena and Leonard Susskind, building on the ideas of Mark Van Raamsdonk and Brian Swingle. Maldacena and Susskind posit that the solution to the firewall problem may come in the form of wormholes.

It makes you wonder if ALL entanglement isn't an example of wormholes, ahem, Einstein-Rosen Bridges attached to particles.  Hence, the title.

Paper link.

Quantum Entanglement Gets a Step Closer to Being Useful

Teleportation is one of the more extraordinary phenomena in the quantum world. It allows a quantum object, such as a photon or electron, to travel from one location to another without passing through the space in between.

Teleportation is a standard procedure in any decent quantum mechanics laboratory. Physicists use it on a daily basis for quantum communication and quantum computation.

If that sounds exotic, you ain’t seen nothing yet; teleportation is about to get a whole lot weirder. That’s because until now, physicists have only been able to teleport single particles, one at a time. Today, Christine Muschik at the Mediterranean Technology Park in Barcelona and a bunch of mates say they’ve worked out how to teleport quantum stuff continuously.

That will allow them to manipulate one quantum particle while watching the effects occur in another particle elsewhere. That’s essentially quantum remote control.

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The trick that physicists have perfected is to arrange this interaction so that the second entangled particle ends up in the same state as the quantum particle called X. This isn’t just a very similar state, it is an identical state—no measurement could distinguish this particle from the original X. When this happens, X has been teleported.

The new technique works in a similar way. First, physicists create a pair of entangled particles. They then place one particle in a varying magnetic field to influence its state.

The new trick that they’ve discovered is to arrange this experiment so that manipulation of the first particle causes the state of its entangled partner to change in the same way.

In other words, they use the magnetic field in one region of space to continuously control the state of a particle somewhere else in space. Or as Muschick and co put it: “We show how the ability to perform quantum operations continuously and deterministically can be leveraged for inducing nonlocal dynamics between two separate parties.”

The new technique is based on a subtle trick. Physicists have long known that entanglement is a fragile thing–a measurement on one of the pair destroys the link between them, which is why physicists have only been able to teleport single particles, one at a time.

Indeed, this is a general problem in the quantum world—sneeze and you destroy the quantum nature of the system you are studying.

In recent years, however, physicists have discovered how to manipulate quantum objects without destroying their quantum nature. The trick is to nudge them very gently. Doing this continuously eventually produces a significant change while preserving the quantum characteristics of the system.

The breakthrough that Muschik and co have made is to work out how to perform the same kind of gentle nudges on an entangled system, something that immediately leads to quantum remote control.