Good sci fi, but … From astrophysicist Paul Sutter at Space.com: The concept of wormholes got its start when physicist Ludwig Flamm, and later Albert Einstein and Nathan Rosen, realized that black holes can be “extended.” When one goes about solving the fantastically complicated equations of general relativity, the machinery that predicts a black hole also predicts a phenomenon called a white hole. A white hole is pretty much what you think: Whereas a black hole’s event horizon marks a region of space that once you enter you can’t leave, it’s impossible to enter a white hole’s horizon, although anything already in there can escape. That same mathematical machinery delivers a bonus, too: All black holes would be naturally “connected” Read More ›

In “What Was Our Universe Like Before the Big Bang?”, Ryan F. Mandlebaum offers some thoughts at Gizmodo: To be perfectly clear, we can’t definitively answer this question—but we can speculate wildly, with the help of theoretical physicist Sean Carroll from the California Institute of Technology. Carroll gave a talk last month at the bi-annual meeting of the American Astronomical Society in Grapevine, Texas, where he walked through several pre-Bang possibilities that would result in a universe like ours. Again, this is a speculation, not theory. “As of yet, these aren’t established as laws of physics we understand or have checked in any way,” said Carroll. As Peter Woit, a theoretical physicist at Columbia University put it to Gizmodo, “A Read More ›

As science culture tries to remake itself a the religion of naturalism, we can expect much more of this stuff. From Daniel Brown at LiveScience: 6. Moving stars Meanwhile, a wandering star on its path through the Milky Way might come so close to our sun that it would interact with the rocky “Oort cloud” at the edge of the solar system, which is the source of our comets. This might lead to an increased chance of a huge comet hurtling to Earth. Another roll of the dice. The sun itself follows a path through the Milky Way that takes us through more or less dense patches of interstellar gas. Currently we are within a less dense bubble created by Read More ›

In Biological Theory (2015): There are currently three major theories on the origin and evolution of the genetic code: the stereochemical theory, the coevolution theory, and the error-minimization theory. The first two assume that the genetic code originated respectively from chemical affinities and from metabolic relationships between codons and amino acids. The error-minimization theory maintains that in primitive systems the apparatus of protein synthesis was extremely prone to errors, and postulates that the genetic code evolved in order to minimize the deleterious effects of the translation errors. This article describes a fourth theory which starts from the hypothesis that the ancestral genetic code was ambiguous and proposes that its evolution took place with a mechanism that systematically reduced its ambiguity Read More ›

Transposable elements (transposons, jumping genes) From Genome Biology and Evolution: At the most basic level of inquiry, the percent of a genome derived from TEs, vertebrate genomes can vary from 6 to 60%. If one takes into account aspects of TE diversity, accumulation histories, and even variation in repeat annotations themselves, it becomes difficult to build a coherent narrative that adequately explains repeat variation across vertebrates. Generally, higher levels of TE diversity correlate with the age of vertebrate lineages; lineages that have existed for longer periods, such as fishes, and deep-branching tetrapods tend to have higher TE diversity than more recent radiations, such as birds and mammals. However, as the number of vertebrate genome assemblies increases, exceptions to this pattern Read More ›

No, look, we are just passing this on, on our way out to do chores.* From Angela Chen at The Verge: Donald Trump has only been president for two weeks, but if you’re not happy about the new administration, those 14 days might feel more like 14 years. That’s normal: our brains really do distort time based on how we’re feeling. It’s an evolutionary trick that was helpful when large predators lurked around every corner, but less helpful now as the days seem to drag by.More. Why do probable urbanites feel they intimately know what it would take to survive in the Old Stone Age? Skinny: It was never helpful not to have a good sense of time, just like Read More ›

We learn from Tracy Vence at The Scientist that evolutionary biologist Patricia Princehouse, interviewed, is organizing a March for Science in Cleveland: Patricia Princehouse: I never expected to be an activist of any kind, but when the creationists tried to take over the public school science curricula in Ohio, I had to say something. At first, when we went to Columbus, I said I would only do the science part—I had nothing to say about the legal things or the politics. We went down there, and we said what [they were] teaching . . . was wrong. And, basically, they said, We don’t care. It’s what our constituents want. I was very naive. I was completely floored by this. Eventually Read More ›

From BioMedCentral: Given that all six receptor families (two each for octopamine, tyramine, and norepinephrine) can be found in representatives of the two major clades of Bilateria, the protostomes and the deuterostomes, all six receptors must have coexisted in the last common ancestor of the protostomes and deuterostomes.” Based on the presumption of common ancestry, this pushes back the origin of this complex signalling system into the Precambrian, and it suggests that subsequent evolution has more to do with losses than gains. “Our study also contributes to the understanding of nervous system evolution in bilaterians by revealing extensive losses during the history of one of the major classes of neurotransmitter systems. – Philipp Bauknecht and Gáspár Jékely, Ancient coexistence of Read More ›

Except where dinosaurs or media-friendly modern species are in play, extinction barely rates a yawn. But here is an interesting item by Veronika Meduna at New Scientist, on a plan to return an ecosystem to a previous time: We are inside the old water reservoir for New Zealand’s capital, Wellington. Over the past two decades, it has undergone an extraordinary transformation, from urban utility to ecological haven. During the day, large forest parrots called kaka swoop over tuatara, the only survivors of a prehistoric group of reptiles. Night-time visitors have a good chance of crossing paths with a little spotted kiwi. Hihi – small black, white and yellow birds that had once disappeared from New Zealand’s main islands – are Read More ›

Further to “Substantial evidence” claimed for universe as a hologram: From phyicist Chris Lee at Ars Technica: Universe neither confirms nor denies its holographic nature The standard approach makes use of quantum field theory, which, when simplified to the point of predictions, results in a range of “cold dark matter plus inflation” models. These models are already known to fit the data from Planck superbly. But in recent years, there has been substantial progress in calculating some of the more annoying parts of quantum field theory. These are referred to as loop corrections, and they can be very difficult. The researchers made use of an additional loop correction to constrain the parameters that go into the model, which resulted in Read More ›

From ScienceDaily: A holographic universe, an idea first suggested in the 1990s, is one where all the information, which makes up our 3D ‘reality’ (plus time) is contained in a 2D surface on its boundaries. Professor Kostas Skenderis of Mathematical Sciences at the University of Southampton explains: “Imagine that everything you see, feel and hear in three dimensions (and your perception of time) in fact emanates from a flat two-dimensional field. The idea is similar to that of ordinary holograms where a three-dimensional image is encoded in a two-dimensional surface, such as in the hologram on a credit card. However, this time, the entire universe is encoded!” Encoded? Funny that. What’s the deal here? Theoretical physicists and astrophysicists, investigating irregularities in Read More ›

From Dan Jones, reviewing naturalist philosopher Daniel Dennett’s Bacteria to Bach and Back: The Evolution of Minds at Nature: Dennett reprises his long-held counter-intuitive idea that consciousness is a ‘user illusion’ similar to the interface of an app, through which people interact with the program without understanding how it works. Memetic apps in our brains, Dennett argues, create a ‘user interface’ that “renders the memes ‘visible’ to the ‘self’”, authoring “both words and deeds”. Critics often quip that Dennett doesn’t explain consciousness so much as explain it away, or duck the challenge entirely, and this chapter is unlikely to bring them around. When it comes to plugging the hole of subjective experience, sceptics are likely to see his solution as Read More ›

From Michael D. Lemonick, author of The Perpetual Now: A Story of Amnesia, Memory, and Love (2017), at Wall Street Journal: Our ‘flashbulb memories’ of shocking events like the Challenger disaster or 9/11 seem sharp but are almost always inaccurate Scientists have long known that memory is unreliable. It isn’t like a video recorder, storing events faithfully for the future, as the experimental psychologist Elizabeth Loftus of the University of California, Irvine, likes to say. What we remember is usually based on what actually happened—but tainted by related information that we might have acquired days or even years later. We might talk over the event with friends, for example, mingling their own memories with our own. We might read about Read More ›

Further to: Geologist on why a scientists’ march on Washington is a bad idea, oceanographer Helen Czerski writes at Guardian: Now, in the age of Google, the frontiers of knowledge are misleadingly comprehensible rather than inaccessible. Their very accessibility means that we may not see the complex context before arriving at each nugget of information and often, we don’t want to. One of the most contentious statements of 2016 was “Britain has had enough of experts”, but perhaps a more useful starting point for debate is “have people have had enough of complexity”? It applies to science as well as politics. The problem is that the world really is complex. And the other problem is that no-one has time to Read More ›

From coastal geologist Robert S. Youngjan at New York Times: Talk is growing about a March for Science on Washington, similar to the Women’s March the day after President Trump’s inauguration. It is a terrible idea. Among scientists, understandably, there is growing fear that fact-based decision making is losing its seat at the policy-making table. There’s also overwhelming frustration with the politicization of science by climate change skeptics and others who see it as threatening to their interests or beliefs. But trying to recreate the pointedly political Women’s March will serve only to reinforce the narrative from skeptical conservatives that scientists are an interest group and politicize their data, research and findings for their own ends. More. Good points but he Read More ›