Universe is Not Expanding After All, Scientists Say New evidence, based on detailed measurements of the size and brightness of hundreds of galaxies, indicates that the Universe is not expanding after all, says a team of astrophysicists led by Eric Lerner from Lawrenceville Plasma Physics. This image shows a star forming region in a nearby galaxy known as the Large Magellanic Cloud. Image credit: ESA / Hubble. In their study, the scientists tested one of the striking predictions of the Big Bang theory – that ordinary geometry does not work at great distances. In the space around us, on Earth, in the Solar System and our Milky Way Galaxy, as similar objects get farther away, they look fainter and smaller. In contrast, the Big Bang theory tells us that in an expanding Universe objects actually should appear fainter but bigger. So in an expanding Universe the most distant galaxies should have hundreds of times dimmer surface brightness than similar nearby galaxies, making them actually undetectable with present-day telescopes. Eric J.
What is a gauge? | What's new “Gauge theory” is a term which has connotations of being a fearsomely complicated part of mathematics – for instance, playing an important role in quantum field theory, general relativity, geometric PDE, and so forth. But the underlying concept is really quite simple: a gauge is nothing more than a “coordinate system” that varies depending on one’s “location” with respect to some “base space” or “parameter space”, a gauge transform is a change of coordinates applied to each such location, and a gauge theory is a model for some physical or mathematical system to which gauge transforms can be applied (and is typically gauge invariant, in that all physically meaningful quantities are left unchanged (or transform naturally) under gauge transformations). I was asked recently to explain what a gauge theory was, and so I will try to do so in this post. – Coordinate systems – More generally, a coordinate system can be viewed as an isomorphism and “. , or even , if the origin O and basis vectors to .
String Theory and the Scientific Method | Not Even Wrong There’s a new philosophy of science book out, Richard Dawid’s String Theory and the Scientific Method (available online here if your institution is paying Cambridge University Press appropriately or if you have a credit card). It comes with endorsements from string theorists David Gross and John Schwarz, with Schwarz writing: Richard Dawid argues that string theory plays a novel role in the scientific process that has been neglected by philosophers of science. I believe that this book is a valuable contribution to the philosophy of science, which should interest practicing scientists as well as those who are more interested in the methodology of science. Dawid is a particle theorist turned philosopher, and as you might guess from the endorsement, he approaches string theory from an enthusiast’s point of view. This book has been on my mind ever since I left physics and turned to philosophy in the year 2000. In Dawid’s description, string theorists are still partying like it’s 1999:
untitled The Universe Magnified This is one of the most beautiful infographics we've ever seen: a high resolution view of different levels of the universe. Our favorite parts are the jaw-dropping nebulae and then the point where you see the size of Pluto compared to Texas. Puts things into perspective. Try it out in full-screen mode: Copyright 2012. Embed this infographic on your site! <iframe width="600" height="388" scrolling="no" src=" frameborder="0" allowfullscreen></iframe><br />Copyright 2012. To get started with the infographic, click on one of the nine entry point images. The slider at the bottom of the screen lets you move around from bigger to smaller and smaller to bigger. And in between you see every day objects like animals and buildings and planets and stars. Have fun with this!
Potts model The model is named after Renfrey Potts, who described the model near the end of his 1951 Ph.D. thesis. The model was related to the "planar Potts" or "clock model", which was suggested to him by his advisor, Cyril Domb. The four-state planar Potts model is sometimes known as the Ashkin–Teller model, after Julius Ashkin and Edward Teller, who considered an equivalent model in 1943. Physical description where n = 1, ..., q and that the interaction Hamiltonian be given by with the sum running over the nearest neighbor pairs (i, j) over all lattice sites. What is now known as the standard Potts model was suggested by Potts in the course of the solution above, and uses a simpler Hamiltonian, given by: where δ(si, sj) is the Kronecker delta, which equals one whenever si = sj and zero otherwise. The q=2 standard Potts model is equivalent to the Ising model and the 2-state vector Potts model, with Jp = −2Jc. Discussion Measure theoretic description Interaction energy
LIGO - Laser Interferometer Gravitational Wave Observatory Everything We Just Found Out About Pluto, Courtesy of New Horizons - Futurism | Futurism Page 1 of 24612345...102030...»Last » How to Process Your Own Colour Images from Hubble Data The Hubble Space Telescope uses a number of different filters when taking images of objects. The best wideband filters for the production of colour images are F435W, F439W, F450W, F555W, F606W, F675W, F702W, F791W, and F814W. Narrowband filters used include F437N, F502N, F656N, F658N, and F673N. 1Locate the fourth image in the result for the search of NGC 604 above and you will find the file name "hst_05237_02_wfpc2_f814w_wf" below it. For this guide, download hst_05237_02_wfpc2_f814w_wf, hst_05237_02_wfpc2_f555w_wf, and hst_05237_02_wfpc2_f336w_wf.
Relationist Quantum Gravity: ← Quantum Weirdness ↑ → Quantum theory is famous for the paradoxical way in which it describes the universe. More strictly the paradoxes lie in the interpretation of quantum mechanics, not in its mathematical structure. Many declare that interpretation is not the business of physics. This section contains a general description of experimental and theoretical issues raised by quantum theory. Wave Particle Duality When we measure the position of a particle it appears as a point-like object with a precise position in space, but when left to its own devices, it evolves according to the laws of wave mechanics. The Copenhagen interpretation is not a unique interpretation, but rather a number of ideas discussed by various physicists in Copenhagen during the early part of the century. Young’s Slits Electrons as Waves This raises the questions “Which slit did the particle come through?” To minimise the effect of shining a light to decide which slit the electron came through, a very dim light might be tried. 1.