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Discussion of the Essence# programming language, and related issues and technologies. |
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UC San Diego physicists devise viable design for spin-based electronics from PhysOrg.com
Physicists at the University of California, San Diego have proposed a design for a semiconductor computer circuit based on the spin of electrons. They say the device would be more scalable and have greater computational capacity than conventional silicon circuits.
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Single spinning nuclei in diamond offer a stable quantum computing building block from PhysOrg.com
At room temperature, carbon-13 nuclei in diamond create stable, controllable quantum register
Surmounting several distinct hurdles to quantum computing, physicists at Harvard University have found that individual carbon-13 atoms in a diamond lattice can be manipulated with extraordinary precision to create stable quantum mechanical memory and a small quantum processor, also known as a quantum register, operating at room temperature. The finding brings the futuristic technology of quantum information systems into the realm of solid-state materials under ordinary conditions.
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UCR physicist demonstrates how light can be used to remotely operate micromachines from PhysOrg.com
Light changes the Casimir force, a weak attraction between close objects, says Umar Mohideen
A research team led by Umar Mohideen, a physicist at the University of California, Riverside, has demonstrated in the laboratory that the Casimir force – the small attractive force that acts between two close parallel uncharged conducting plates – can be changed using a beam of light, making the remote operation of micromachines a possibility.
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From the article "Life 2.0" (MSNBC):
So far, researchers have fabricated individual biological building blocks, but they have yet to create an entirely new synthetic self-replicating organism. "Chemical synthesis of life has been a standing challenge to synthetic organic chemistry," says Venter (with palpable impatience). But SynBio researchers see no reason to wait until whole organisms can be created from scratch. They are happy to stitch together lab-designed biological components, or "biodevices," with parts of natural cells to construct hybrid organisms. The SynBio enterprise is not some ivory-tower exercise but a pragmatic field that could soon produce results. Church, who at 53 is an elder SynBio guru, thinks it could happen as soon as two years from now if funding is ramped up and scientists don't run into major snags.
In a first, scientists develop tiny implantable biocomputers from PhysOrg.com
Researchers at Harvard University and Princeton University have made a crucial step toward building biological computers, tiny implantable devices that can monitor the activities and characteristics of human cells. The information provided by these "molecular doctors," constructed entirely of DNA, RNA, and proteins, could eventually revolutionize medicine by directing therapies only to diseased cells or tissues.
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In the paper The Mathematical Universe (PDF,) cosmologist Max Tegmark takes the (epistemological) position that the External Reality Hypothesis (ERH) strongly implies the Mathematical Universe Hypothesis (MUH.) MUH holds that reality isn't just described (modeled) by mathematics, but that mathematics and reality are actually deeply equivalent.
The abstract of the paper says "I explore physics implications of the External Reality Hypothesis (ERH) that there exists an external physical reality completely independent of us humans. I argue that with a sufficiently broad definition of mathematics, it implies the Mathematical Universe Hypothesis (MUH) that our physical world is an abstract mathematical structure. I discuss various implications of the ERH and MUH, ranging from standard physics topics like symmetries, irreducible representations, units, free parameters and initial conditions to broader issues like consciousness, parallel universes and Gödel incompleteness. I hypothesize that only computable and decidable (in Gödel's sense) structures exist, which alleviates the cosmological measure problem and help explain why our physical laws appear so simple. I also comment on the intimate relation between mathematical structures, computations, simulations and physical systems."
In another paper, Parallel Universes, Tegmark defines a taxonomy of different types of Universes (reminiscent of Georg Cantor's taxonomy of different types of infinities.) The existence of Type IV Universes would be a probable consequence of the Mathematical Universe Hypothesis.
In addition to making me think more deeply, and more outside the box, than anything I've read since encountering Eliezer Yudkowsky's essay Staring into the Singularity, these two papers by Tegmark strongly remind me of several things that may be deeply related:
The article "Is the evidence for 'alien' universes all around us?" (New Scientist) discusses the possibility that the cosmic microwave background (CMB) left over from the big bang shows evidence that our universe must have collided with others during it's initial period of space-time inflation.
As intriguing as that sounds, it raises yet another issue that just might be of more importance. Apparently, this would mean that there is yet another way for our Universe to end--without warning, and with no known way to prevent it. If you were thinking that the Big Crunch or the Heat Death of the Universe were the only two options, think again:
If universes really are crashing into us willy-nilly, should we be worrying about a fatal collision? "It's true, there is always a chance we will be hit by a lethal bubble, which would come without warning," says Vilenkin. "But since we'll just evaporate in an instant and there's nothing we can do to stop it, there's really no use in worrying."
From the article Diamonds tell tale of comet that killed off the cavemen:
Scientists will outline dramatic evidence this week that suggests a comet exploded over the Earth nearly 13,000 years ago, creating a hail of fireballs that set fire to most of the northern hemisphere.
Primitive Stone Age cultures were destroyed and populations of mammoths and other large land animals, such as the mastodon, were wiped out. The blast also caused a major bout of climatic cooling that lasted 1,000 years and seriously disrupted the development of the early human civilisations that were emerging in Europe and Asia.
Researchers Put 'Spin' in Silicon, Advance New Age of Electronics from PhysOrg.com
Electrical engineers from the University of Delaware and Cambridge NanoTech have demonstrated for the first time how the spin properties of electrons in silicon--the world's most dominant semiconductor, used in electronics ranging from computers to cell phones--can be measured and controlled.
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Normally, if a sci/tech story has already been published on Slashdot before I can post it here, I don't post it here (that happens a lot, by the way--and even more often, Slashdot posts on a story after I have done the same.) However, in some cases, the story is simply too important to ignore. For example, there's this article:
Predictive Modeling of Signaling Crosstalk during C. elegans Vulval Development, which presents research results that indicate we're now "going to the next level" in our ability to model biology computationally. We've been modeling biology at the level of genes and amino acids for quite some time now. The next level above that would be the ability to model proteins and protein-based biochemical messaging pathways as a system of inter-operating machines. That's what the above-referenced article is about. Quoting the abstract:
Here, we have developed a dynamic computational model incorporating the current mechanistic understanding of gene interactions during this patterning process. A key feature of our model is the inclusion of multiple modes of crosstalk between the epidermal growth factor receptor (EGFR) and LIN-12/Notch signaling pathways, which together determine the fates of the six vulval precursor cells (VPCs). Computational analysis, using the model-checking technique, provides new biological insights into the regulatory network governing VPC fate specification and predicts novel negative feedback loops. In addition, our analysis shows that most mutations affecting vulval development lead to stable fate patterns in spite of variations in synchronicity between VPCs.
