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Archive for the ‘biological’ category: Page 147

Apr 5, 2020

Quantum biology revisited

Posted by in categories: biological, engineering, quantum physics

This could lead to biological teleportation. :3.


Photosynthesis is a highly optimized process from which valuable lessons can be learned about the operating principles in nature. Its primary steps involve energy transport operating near theoretical quantum limits in efficiency. Recently, extensive research was motivated by the hypothesis that nature used quantum coherences to direct energy transfer. This body of work, a cornerstone for the field of quantum biology, rests on the interpretation of small-amplitude oscillations in two-dimensional electronic spectra of photosynthetic complexes. This Review discusses recent work reexamining these claims and demonstrates that interexciton coherences are too short lived to have any functional significance in photosynthetic energy transfer. Instead, the observed long-lived coherences originate from impulsively excited vibrations, generally observed in femtosecond spectroscopy. These efforts, collectively, lead to a more detailed understanding of the quantum aspects of dissipation. Nature, rather than trying to avoid dissipation, exploits it via engineering of exciton-bath interaction to create efficient energy flow.

Over the past decade, the field of quantum biology has seen an enormous increase in activity, with detailed studies of phenomena ranging from the primary processes in vision and photosynthesis to avian navigation (1, 2). In principle, the study of quantum effects in complex biological systems has a history stretching back to the early years of quantum mechanics (3); however, only recently has it truly taken center stage as a scientifically testable concept. While the overall discussion has wide-ranging ramifications, for the purposes of this Review, we will focus on the subfield where the debate is most amenable to direct experimental tests of purported quantum effects—photosynthetic light harvesting.

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Apr 2, 2020

Spiral patterns in living cells could be used to create biological computers

Posted by in categories: biological, computing, quantum physics

Vortices in starfish eggs resemble those found in quantum fluids.

Mar 28, 2020

The Earth as a Superorganism — Further Thoughts

Posted by in category: biological

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This article follows on from several others on this theme that I wrote some time ago, for details of which see footnote.

The idea of the earth as a superorganism re-emerged in modern times with the work of the independent scientist James Lovelock and his Gaia hypothesis. This was developed further by the spiritually oriented writer Peter Russell in The Awakening Earth.

Continue reading “The Earth as a Superorganism — Further Thoughts” »

Mar 26, 2020

Your teeth may record your life’s most important biological events

Posted by in categories: biological, law enforcement

Sediment layers in rock or tree rings can hold clues to what the environment was like at different times in the past – and the same idea may even apply to your own teeth. Scientists at New York University have found that the material that makes up tooth roots preserves a lifelong record of stresses on the body, such as childbirth, illness, and even prison time.

While most of a tooth doesn’t grow once it’s popped up in your jaw, the tissue around the roots do. Known as cementum, this stuff regularly adds new layers after the tooth surfaces. And for this study, the researchers investigated the hypothesis that major physiological events would leave their mark in these layers.

To test the idea, the team examined 47 teeth from 15 different people, between the ages of 25 and 69. The life histories of all of these people were known, including things like whether they’d given birth, had major illnesses or even moved from rural to urban areas. Crucially, they also knew what ages these events had occurred.

Mar 24, 2020

Team develops photosynthetic proteins for expanded solar energy conversion

Posted by in categories: bioengineering, biological, solar power, sustainability

A team of scientists, led by the University of Bristol, has developed a new photosynthetic protein system enabling an enhanced and more sustainable approach to solar-powered technological devices.

The initiative is part of a broader effort in the field of to use proteins in place of man-made materials which are often scarce, expensive and can be harmful to the environment when the device becomes obsolete.

The aim of the study, published today in Nature Communications, was the development of “chimera” complexes that display poly-chromatic solar energy harvesting.

Mar 18, 2020

‘Spaceship Earth’ Documentary Tells the Story of Biosphere 2

Posted by in categories: biological, education, space travel

This man lived inside a self-sustaining glass biosphere for 2 whole years to test drive what life would be like for humans on Mars via NowThis.

Mar 16, 2020

Mars Likely Has Living Microbes At Its Poles, Say Researchers

Posted by in categories: biological, space

Mars polar researchers offer a shortcut to detecting life on the Red planet.

Mar 14, 2020

Don’t Let Robots Pull the Trigger

Posted by in categories: biological, military, robotics/AI

Ban Killer Robots

“Robotic weapons that target and destroy without human supervision are poised to start a revolution in warfare comparable to the invention of gunpowder or the atomic bomb. The prospect poses a dire threat to civilians—and could lead to some of the bleakest scenarios in which artificial intelligence runs amok. A prohibition on killer robots, akin to bans on chemical and biological weapons, is badly needed. But some major military powers oppose it.”


Weapons that kill enemies on their own threaten civilians and soldiers alike.

Mar 13, 2020

Initialization of quantum simulators

Posted by in categories: biological, particle physics, quantum physics

Simulating computationally complex many-body problems on a quantum simulator has great potential to deliver insights into physical, chemical and biological systems. Physicists had previously implemented Hamiltonian dynamics but the problem of initiating quantum simulators to a suitable quantum state remains unsolved. In a new report on Science Advances, Meghana Raghunandan and a research team at the institute for theoretical physics, QUEST institute and the Institute for quantum optics in Germany demonstrated a new approach. While the initialization protocol developed in the work was largely independent of the physical realization of the simulation device, the team provided an example of implementing a trapped ion quantum simulator.

Quantum simulation is an emergent technology aimed at solving important open problems relative to high-temperature superconductivity, interacting quantum field theories or many-body localization. A series of experiments have already demonstrated the successful implementation of Hamiltonian dynamics within a quantum simulator—however, the approach can become challenging across quantum phase transitions. In the new strategy, Raghunandan et al. overcame this problem by building on recent advances in the use of dissipative quantum systems to engineer interesting many-body states.

Almost all many-body Hamiltonians of interest remain outside a previously investigated class and therefore require generalization of the dissipative state preparation procedure. The research team therefore presented a previously unexplored paradigm for the dissipative initialization of a quantum simulator by coupling the many-body system performing the quantum simulation to a dissipatively driven auxiliary particle. They chose the energy splitting within the auxiliary particle to become resonant with the many-body excitation gap of the system of interest; described as the difference of the ground-state energy and the energy of the first excited state. During such conditions of resonance, the energy of the quantum simulator could be transferred efficiently to the auxiliary particle for the former to be cooled sympathetically, i.e., particles of one type, cooled particles of another type.

Mar 13, 2020

Slime Mold Simulations Map Dark Matter Holding Universe Together

Posted by in categories: biological, cosmology, evolution

The behavior of one of nature’s humblest creatures is helping astronomers probe the largest structures in the universe.

The single-cell organism, known as slime mold (Physarum polycephalum), builds complex filamentary networks in search of food, finding near-optimal pathways to connect different locations. In shaping the universe, gravity builds a vast cobweb structure of filaments tying galaxies and clusters of galaxies together along faint bridges hundreds of millions of light-years long. There is an uncanny resemblance between the two networks: one crafted by biological evolution, and the other by the primordial force of gravity.

The cosmic web is the large-scale backbone of the cosmos, consisting primarily of the mysterious substance known as dark matter and laced with gas, upon which galaxies are built. Dark matter cannot be seen, but it makes up the bulk of the universe’s material. The existence of a web-like structure to the universe was first hinted at in the 1985 Redshift Survey conducted at the Harvard-Smithsonian Center for Astrophysics. Since those studies, the grand scale of this filamentary structure has grown in subsequent sky surveys. The filaments form the boundaries between large voids in the universe.