Posts Tagged ‘Universe’
Why was entropy so low at the Big Bang? (source: Internet Encyclopedia of Philosophy)
Back in 2010, SUNY-Buffalo physics professor Dejan Stojkovic and colleagues made a simple– a radically simple– suggestion: that the early universe — which exploded from a single point and was very, very small at first — was one-dimensional (like a straight line) before expanding to include two dimensions (like a plane) and then three (like the world in which we live today).
The core idea is that the dimensionality of space depends on the size of the space observed, with smaller spaces associated with fewer dimensions. That means that a fourth dimension will open up — if it hasn’t already — as the universe continues to expand. (Interesting corollary: space has fewer dimensions at very high energies of the kind associated with the early, post-big bang universe.)
Stojkovic’s notion is challenging; but at the same time, it would help address a number of fundamental problems with the standard model of particle physics, from the incompatibility between quantum mechanics and general relativity to the mystery of the accelerating expansion of the universe.
But is it “true”? There’s no way to know as yet. But Stojkovic and his colleagues have devised a test using the Laser Interferometer Space Antenna (LISA), a planned international gravitational observatory, that could shed some definitive light on the question in just a few years.
As we glance around for evidence of that fourth dimension, we might bid an indeterminate farewell to Ilya Prigogine, the Nobel Laureate whose work on dissipative structures, complex systems, and irreversibility led to the identification of self-organizing systems, and is seen by many as a bridge between the natural and social sciences. He died at the Hospital Erasme in Brussels on this date in 2003.
Prigogine’s 1997 book, The End of Certainty, summarized his departure from the determinist thinking of Newton, Einstein, and Schrödinger in arguing for “the arrow of time”– and “complexity,” the ineluctable reality of irreversibility and instability. “Unstable systems” like weather and biological life, he suggested, cannot be explained with standard deterministic models. Rather, given their to sensitivity to initial conditions, unstable systems can only be explained statistically, probabilistically.
source: University of Texas
By suggesting that mass, time, and length can be converted into one another as the universe evolves, Wun-Yi Shu has proposed a new class of cosmological models that may fit observations of the universe better than the current big bang model. What this means specifically is that the new models might explain the increasing acceleration of the universe without relying on a cosmological constant such as dark energy, as well as solve or eliminate other cosmological dilemmas such as the flatness problem and the horizon problem.
Physorg reports that Dr. Shu’s model has four distinguishing features:
• The speed of light and the gravitational “constant” are not constant, but vary with the evolution of the universe.
• Time has no beginning and no end; i.e., there is neither a big bang nor a big crunch singularity.
• The spatial section of the universe is a 3-sphere [a higher-dimensional analogue of a sphere], ruling out the possibility of a flat or hyperboloid geometry.
• The universe experiences phases of both acceleration and deceleration.
So, in the beginning there was… no beginning…
(TotH to reader M H-H)
As we paste together another Möbius strip, we might recall that it was this date in 1693 that is traditionally ascribed to Benedictine friar Dom Pérignon’s invention of Champagne.
In fact, the the good father didn’t actually invent sparkling wine: The oldest recorded sparkling wine is Blanquette de Limoux, which was apparently invented by a different bunch of Benedictines in the Abbey of Saint Hilaire near Carcassonne in 1531. Then, over a century later, the English scientist and physician Christopher Merret documented the addition of sugar to a finished wine to create a second fermentation– six years before Dom Perignon set foot in the Abbey of Hautvillers (where he did, in fact, make several improvements to the process of making bubbly) and almost 40 years before it was claimed that the famed Benedictine monk invented Champagne. Merret presented the Royal Society with a paper in which he detailed what is now called “méthode champenoise” in 1662.
Still, today’s a good day to raise a glass in thanks.
As all of one’s assumptions about the future (and thus the past) seem to be weakening, two dispatches from the world of science are genuinely foundation-shaking…
Just suppose that Darwin’s ideas were only a part of the story of evolution. Suppose that a process he never wrote about, and never even imagined, has been controlling the evolution of life throughout most of the Earth’s history. It may sound preposterous, but this is exactly what microbiologist Carl Woese and physicist Nigel Goldenfeld, both at the University of Illinois at Urbana-Champaign, believe. Darwin’s explanation of evolution, they argue, even in its sophisticated modern form, applies only to a recent phase of life on Earth.
At the root of this idea is overwhelming recent evidence for horizontal gene transfer – in which organisms acquire genetic material “horizontally” from other organisms around them, rather than vertically from their parents or ancestors. The donor organisms may not even be the same species. This mechanism is already known to play a huge role in the evolution of microbial genomes, but its consequences have hardly been explored. According to Woese and Goldenfeld, they are profound, and horizontal gene transfer alters the evolutionary process itself. Since micro-organisms represented most of life on Earth for most of the time that life has existed – billions of years, in fact – the most ancient and prevalent form of evolution probably wasn’t Darwinian at all, Woese and Goldenfeld say…
Woese can’t put a date on when the transition to Darwinian evolution happened, but he suspects it occurred at different times in each of the three main branches of the tree of life, with bacteria likely to have changed first…
As we remember that what has changed can change again, we can read the whole story here.
Second, from ArXiv and ITWire, a suggestion that we might not have as long to figure this out as we have been thinking: entropy in the universe is much higher than previously expected; thus the “heat death” of existence as we’ve known it, much closer. As Tapecutter observes in Slashdot,
In a paper soon to be published in the Astrophysical Journal [ArXiv link, above], Australian researchers have estimated the entropy of the universe is about 30 times higher than previous estimates. According to their research, super-massive black holes “are the largest contributor to the entropy of the observable universe, contributing at least an order of magnitude more entropy than previously estimated.” For those of us who like their science in the form of a car analogy, Dr. Lineweaver compared their results to a car’s gas tank. He states, ‘It’s a bit like looking at your gas gauge and saying “I thought I had half a gas tank, but I only have a quarter of a tank.”
Happily a quarter of a tank should be good for hundreds of thousands (if not millions) of years.
As we regain our bearings, we might note that this was a bad day for revolutionaries of another stripe: it was on this date in 1606 that Guy Fawkes was executed for his role in the Catholic Restorationist “Gunpowder Plot.”
Readers who recall earlier brushes with the “voice-enhancing” software Auto-Tune (e.g.,”All That Glitters…“) will be delighted to know that John Boswell (Colorpulse Music) has turned the technology to a more universal purpose.
A musical tribute to two great men of science. Carl Sagan and his cosmologist companion Stephen Hawking present: “A Glorious Dawn – Cosmos remixed.” Almost all samples and footage taken from Carl Sagan’s Cosmos and Stephen Hawking’s Universe series.
As we listen to the music of the spheres, we might thank our lucky stars for Miguel de Cervantes Saavedra, author of Don Quixote, arguably the first– and arguably the finest– Western novel. He was born on this date in 1547 in Alcalá de Henares, near Madrid.