Lifeboat Foundation

Information variations in a chain-like system are associated to energy transactions with the environment, which can take place reversibly or irreversibly, with a lower theoretical energy limit^22,23. Fluctuations as a consequence of pure computations are on the order of the thermal level (i.e., similar to kT, being k the Boltzmann constant and T the absolute temperature), according to Landauer’s principle. Such energies are negligible at routine human scales but become significant when the size of the system is nanoscopic or smaller, because the work and heat it generates also compare with the thermal level. Small systems are based on nanostructures, including individual molecules and arrangements of atoms, such as biological and quantum systems.

Fluctuation theorems have appeared in recent years explaining quantitatively energy imbalances between forward and reverse pathways or between equilibrium and non-equilibrium processes^24,25. They have been tested experimentally^26,27,28, mostly in biomolecular systems analyzed on a one-by-one basis²⁹. Most of these theorems establish relations among thermodynamic potentials for general systems, often with no specific insight into information theory. This theory, in turn, deals with spatially-indexed, 1-dimensional arrangements of symbols, which may not be necessarily associated to a time order. Recent generalizations separate the role of information and feedback control^30,31, but still the interpretation of non-Markovianity, irreversibility and reversibility in terms of purely informational operations such as reading, writing and error correction^32,33 remains obscured.

Here, we analyze energy exchanges associated to the symbolic management of a sequence of characters, without reference to the physical construction of the chain. Just by considering reversibility at the single sequence level and conservation laws, we next present two pairs of fluctuations equalities in the creation of information sequences, which use depends on energy exchange constraints. Our analysis integrates key information concepts, namely, reading, writing, proof reading and editing in the thermodynamic description of a string of symbols with information.

MR1805/iStock.

The study was published in Nature Astronomy, and it details how simple microbes that fed on hydrogen and excreted methane were likely abundant on Mars roughly 3.7 billion years ago. This was at approximately the same time that the earliest life was forming in Earth’s oceans.

Mounting evidence suggests that humans may have the biological hardware to benefit from some aspects of hibernation. Switching on these mechanisms could treat cardiac arrest, boost longevity and help people travel further into space.

Between 1928 and 1991, the Soviet Union operated the largest biological weapons program in history. What does it look like today?

Michael Levin is a developmental and synthetic biologist at Tufts University, where he is the Vannevar Bush Distinguished Professor of biology. He is a director of the Allen Discovery Center, director at the Tufts Center for Regenerative and Developmental Biology, and principal investigator at the Levin Lab.

0:00 intro.
1:38 bioelectricity and developmental biology.
7:56 memory and conditioning in GRNs.
11:50 is there a privileged cognitive substrate?
13:55 Godel type limits.
15:45 multi-scale competency architecture.
25:12 intelligence.
27:00 conceptual framework for cognition.
29:45 does cognition bottom out somewhere?
36:47 synthetic cognition.
39:23 sci-fi that captures this well.
45:16 consciousness, hard problem, and the consciousness of development.
51:09 where does the self come from?
54:06 how do different emergent levels interact.
56:50 top-down causality.
1:02:28 where do goals come from?
1:07:06 balancing conceptual and empirical work.

Continue reading “Michael Levin on the foundations of cognition | Thing in itself w/ Ashar Khan” »

A paradigm shift in how we think about the functions of the human brain. A long-awaited genetic sequence of Rafflesia arnoldii, the strangest flower in the world. A revelation in sleep science. These are some of the year’s biggest discoveries in neuroscience and other areas of biology. Read the articles in full at Quanta: https://www.quantamagazine.org/the-year-in-biology-20211221/

Quanta Magazine is an editorially independent publication supported by the Simons Foundation.

face_with_colon_three circa 2021.

Think about where our energy comes from: drilling rigs and smokestacks, windmills and solar panels. Lithium-ion battery packs might even come to mind.

We probably don’t think about the farms that comprise over one-third of Earth’s total land area. But farms can also be an energy source. Barcelona-based battery company Bioo is generating electricity from the organic matter in soil and creating biological batteries that can power agricultural sensors, a growing 1.36 billion dollar global market.

Continue reading “How biological batteries can generate renewable energy from soil” »

What we know about Venus so far has been gathered from several past probes.

With a slightly smaller diameter than Earth, Venus orbits closer to the Sun. This means that any water on the surface would have evaporated shortly after its formation, starting its greenhouse effect. Early and sustained volcanic eruptions created lava plains and increased the carbon dioxide in the atmosphere — starting the runaway greenhouse effect, which increased the temperature from just a little higher than Earth’s to its current high value of 475°C.

While Venus’s year is shorter than ours (225 days), its rotation is very slow (243 days) and “retrograde” — the other way round to Earth. The slow rotation is related to a lack of magnetic field, resulting in a continuing loss of atmosphere. Venus’ atmosphere “super-rotates” faster than the planet itself. Images from many missions show V-shaped patterns of clouds composed of sulphuric acid droplets.

Continue reading “The clouds of Venus may be habitable — a crewed flyby could confirm the theory” »

Researchers have reported a nano-sized neuromorphic memory device that emulates neurons and synapses simultaneously in a unit cell, another step toward completing the goal of neuromorphic computing designed to rigorously mimic the human brain with semiconductor devices.

Neuromorphic computing aims to realize artificial intelligence (AI) by mimicking the mechanisms of neurons and synapses that make up the human brain. Inspired by the cognitive functions of the human brain that current computers cannot provide, neuromorphic devices have been widely investigated. However, current Complementary Metal-Oxide Semiconductor (CMOS)-based neuromorphic circuits simply connect artificial neurons and synapses without synergistic interactions, and the concomitant implementation of neurons and synapses still remains a challenge. To address these issues, a research team led by Professor Keon Jae Lee from the Department of Materials Science and Engineering implemented the biological working mechanisms of humans by introducing the neuron-synapse interactions in a single memory cell, rather than the conventional approach of electrically connecting artificial neuronal and synaptic devices.

Similar to commercial graphics cards, the artificial synaptic devices previously studied often used to accelerate parallel computations, which shows clear differences from the operational mechanisms of the human brain. The research team implemented the synergistic interactions between neurons and synapses in the neuromorphic memory device, emulating the mechanisms of the biological neural network. In addition, the developed neuromorphic device can replace complex CMOS neuron circuits with a single device, providing high scalability and cost efficiency.