Steve Cartledge
Autodidacticism
Mind and Brain. Fractals. Douglas Adams. Noam Chomsky. Steve Jobs tribute from mlfilms.com Memory & Imagination. Red Queen's Hypothesis. The Red Queen hypothesis, also referred to as Red Queen's, Red Queen's race or The Red Queen Effect, is an evolutionary hypothesis which proposes that organisms must constantly adapt, evolve, and proliferate not merely to gain reproductive advantage, but also simply to survive while pitted against ever-evolving opposing organisms in an ever-changing environment, and intends to explain two different phenomena: the constant extinction rates as observed in the paleontological record caused by co-evolution between competing species[1] and the advantage of sexual reproduction (as opposed to asexual reproduction) at the level of individuals.[2] Leigh Van Valen proposed the hypothesis to explain the "Law of Extinction",[1] showing that in many populations the probability of extinction does not depend on the lifetime of this population, instead being constant over millions of years for a given population.
This could be explained by the coevolution of species. The Red Queen at the genus level. Information Management. Science. A Universe from Nothing? | Cosmic Variance. Some of you may have been following a tiny brouhaha (“kerfuffle” is so overused, don’t you think?) That has sprung up around the question of why the universe exists. You can’t say we think small around here. First Lawrence Krauss came out with a new book, A Universe From Nothing: Why There Is Something Rather Than Nothing (based in part on a popular YouTube lecture), which addresses this question from the point of view of a modern cosmologist. Then David Albert, speaking as a modern philosopher of science, came out with quite a negative review of the book in the New York Times. And discussion has gone back and forth since then: here’s Jerry Coyne (mostly siding with Albert), the Rutgers Philosophy of Cosmology blog (with interesting voices in the comments), a long interview with Krauss in the Atlantic, comments by Massimo Pigliucci, and another response by Krauss on the Scientific American site.
I’ve been meaning to chime in, for personal as well as scientific reasons. Executive summary. Structure of influenza virus. In this week’s discussion of swine flu A/Mexico/09 (H1N1), we have considered many aspects of influenza virus biology that might not be familiar to some readers of virology blog. I thought it might be useful to explain how the virus multiplies, how it infects us, and how we combat infection. Today we’ll start with the basic structure of influenza virus, illustrated above. The influenza virion (as the infectious particle is called) is roughly spherical. It is an enveloped virus – that is, the outer layer is a lipid membrane which is taken from the host cell in which the virus multiplies.
Inserted into the lipid membrane are ‘spikes’, which are proteins – actually glycoproteins, because they consist of protein linked to sugars – known as HA (hemagglutinin) and NA (neuraminidase). These are the proteins that determine the subtype of influenza virus (A/H1N1, for example). We’ll discuss later how the HA and NA are given subtype numbers. Understanding the Higgs Boson | Cutting Edge. This is a guest commentary. See Mark Wise's bio below. The Higgs boson is an integral part of our understanding of nature. It is a particle that is an excitation of what is called the Higgs field. The Higgs field permeates all of space and when some of the fundamental particles travel through it they acquire mass. One peculiar aspect of this is that this Higgs field that permeates throughout all space is part of what we call empty space or the vacuum. Going forward we want to see if those predictions are in agreement with the measurements from ATLAS and CMS.
The current theory we have for basic interactions we observe in nature (the strong interactions that bind protons and neutrons in the nucleus of an atom, the weak interactions that are responsible for radioactive decay, and the electromagnetic interactions that play such a crucial role in the structure of atoms and much of modern technology) is called the standard model. One of those features is called the hierarchy puzzle. Symphony of Science - A Wave of Reason. Fibonacci's 'Numbers': The Man Behind The Math. Your Days Are Numbered Try to imagine a day without numbers. Never mind a day, try to imagine getting through the first hour without numbers: no alarm clock, no time, no date, no TV or radio, no stock market report or sports results in the newspapers, no bank account to check.
It's not clear exactly where you are waking up either, for without numbers modern housing would not exist. The fact is, our lives are totally dependent on numbers. You may not have "a head for figures," but you certainly have a head full of figures. Most of the things you do each day depend on and are conditioned by numbers. How did we — as a species and as a society — become so familiar with and totally reliant on these abstractions our ancestors invented just a few thousand years ago? For the most part, the story of numbers was easy to discover. Prior to the thirteenth century, however, the only Europeans who were aware of the system were, by and large, scholars, who used it solely to do mathematics. Quantum entanglement. Quantum entanglement is a physical phenomenon that occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently – instead, a quantum state may be given for the system as a whole.
Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky and Nathan Rosen,[1] describing what came to be known as the EPR paradox, and several papers by Erwin Schrödinger shortly thereafter.[2][3] Einstein and others considered such behavior to be impossible, as it violated the local realist view of causality (Einstein referred to it as "spooky action at a distance"),[4] and argued that the accepted formulation of quantum mechanics must therefore be incomplete. History[edit] However, they did not coin the word entanglement, nor did they generalize the special properties of the state they considered. Concept[edit] Meaning of entanglement[edit] Apparent paradox[edit] The hidden variables theory[edit]
Wave function. However, complex numbers are not necessarily used in all treatments. Louis de Broglie in his later years proposed a real-valued wave function connected to the complex wave function by a proportionality constant and developed the de Broglie–Bohm theory. The unit of measurement for ψ depends on the system. For one particle in three dimensions, its units are [length]−3/2. These unusual units are required so that an integral of |ψ|2 over a region of three-dimensional space is a unitless probability (the probability that the particle is in that region).
For different numbers of particles and/or dimensions, the units may be different and can be found by dimensional analysis.[1] Historical background[edit] In the 1920s and 1930s, quantum mechanics was developed using calculus and linear algebra. Wave functions and function spaces[edit] If the wave function is to change throughout space and time, one would expect the wave function to be a function of the position and time coordinates. Complexity Theory. Game Theory.
Information theory. Life hacks. Life Long Learning. Help.