Those who think cosmology could not get any weirder than it already is (01/15/2008) may want to take note of recent pronouncements by the gurus of universal physics. Physics teachers in particular may feel an obligation to state Bob Berman’s disclaimer (10/06/2004) before class: viz, “Warning: The following contains contemporary cosmology. Reading it can produce disorientation and confusion. Nobody knows what’s going on and nothing you read here is likely to be true.”Questioning sacred Q.M.: The development of Quantum Mechanics in the 1920s and 1930s was one of the iconic scientific revolutions that is hailed as one of the greatest achievements in physics. It had far-reaching consequences for science, philosophy and even religion. Numerous books have stated that it undermined determinism once for all. The uncertainty principle was embedded in the very core of fundamental physics, we were told. Einstein struggled in vain to find “hidden variables” that would explain the apparent indeterminacy of QM behavior. QM has an impressive record in technology, providing the basis for lasers, Josephson junctions in computers, quantum cryptography and much, much more. How, then, could Nature News dare to state on May 15, “why quantum mechanics might be wrong”? Sure enough, an alternative hidden-variables theory called Bohmian mechanics is vying for attention. One of its promoters feels he can test his predictions against those of QM with observations of the cosmic background radiation. At stake is not the huge body of evidence and mathematics behind QM’s success, but the Copenhagen Interpretation – the leading explanation of quantum mechanics that had almost reached the status of accepted truth. The contest is just beginning. Bohmian mechanics is the underdog. Stay tuned.Time travel: In QM, we were taught that observing a quantum event collapses the wave function and gives “classical” reality to alternative outcomes. The textbook illustration is Schrödinger’s thought experiment of a quantum cat in a box being both dead and alive until an observer peeks in and gives reality to one of the two states. The Copenhagen Interpretation of QM has led many to teach that observation creates reality. Now, however, Nature News just reported a “breakthrough experiment” in which researchers pulled back a Schrödinger-Cat type of phenomenon from the brink of classical reality back to a state of quantum indeterminacy. What does this mean? For one thing, it means that “our understanding of how classical reality emerges may be naive.” One British physicist said, “It tells us that we really can’t assume that measurements create reality, because it is possible to erase the effects of a measurement and start again.” Reactions to the paper are mixed. An Australian physicist commented on the experiment, “The quantum world has become more tangible, and the nature of reality even more mysterious.” Nature whimsically subtitled sections of the article with the concepts of reincarnation and time travel.Fractals fracture assumptions: An article in New Scientist Space offered up a weird conjecture: is our universe arranged in a fractal pattern? The question is not without empirical evidence. “A new study of nearly a million galaxies suggests it is,” the article began, “though there are no well-accepted theories to explain why that would be so.” Critics are saying the pattern is an optical illusion. “A lot is at stake,” the article continued, “and the matter distribution has become a source of impassioned debate between those who say the distribution is smooth and homogeneous and those who say it is hierarchically structured and clumpy, like a fractal.” Smooth-and-homogeneous has been the assumption underlying essentially all cosmological models for the past few decades. Looking for patterns in the Sloan Digital Sky Survey of 800,000 galaxies and 100,000 quasars, two Russian cosmologists claim the data show a fractal pattern out to 100,000 light-years at least. A fractal model of the universe will be hard to sell to traditional cosmologists. “Many cosmologists find fault with their analysis, largely because a fractal matter distribution out to such huge scales undermines the standard model of cosmology,” the article said. “According to the accepted story of cosmic evolution, there simply hasn’t been enough time since the big bang nearly 14 billion years ago for gravity to build up such large structures.” Moreover, it would “leave cosmologists without a working model, like acrobats without a net.” Much of the case for smooth-and-homogeneous is based on patterns in the cosmic microwave background (CMB). The article revealed some problems with how that was established. Cosmologists may have missed a fractal pattern, if there is one, by projecting the 3D CMB map onto a 2D surface. Measurements of distant radio galaxies to probe homogeneity are also too uncertain to rule out alternatives, the article said. The implications for dating the universe and for big bang cosmology if the fractal interpretation were to become accepted could hardly be overstated – to say nothing of how this would affect scientists’ confidence in being able to understand the universe and make progress in their scientific explanations. The traditionalists are wagering a case of wine that the apparent fractal pattern is not real.Question time: Time always runs forward, right? The second law of thermodynamics dictates that Humpty Dumpty will never be put back together by the forces of physics. Your coffee will never unstir itself, and you will grow older, not younger. Not so fast, argued Sean M. Carroll in Scientific American last month. “One of the most basic facts of life is that the future looks different from the past,“ he began. “But on a grand cosmological scale, they may look the same.” This could only mean that for those parts of the universe where time moves forward, an equal number could have clocks that run backward. Why? Because the laws of physics don’t care which way time runs – they work equally well regardless. Entropy, furthermore, remains a puzzling concept. Why should things move toward disorder instead of becoming more orderly over time? Carroll repeated his criticism of inflationary cosmology mentioned in our “Paper View” segment from 05/11/2006 (see also 04/18/2008). He also reiterated the problem that for the universe to be in its current state of low entropy now, the entropy at the beginning would have had to be inconceivably low. He criticized inflation as an assumption impersonating an explanation: “Inflation does not, by itself, explain why the early universe has a low entropy; it simply assumes it from the start.” Nor does the once-popular proposal for an eternally oscillating universe get around the entropy problem. Along with Jennifer Chen, a colleague from the University of Chicago, Sean Carroll has instead proposed a time-symmetric universe. The parts of the universe in which time runs forward are balanced by regions where time runs backward. “Entropy can increase without limit through the creation of new baby universes.” The jury is still out on this model, however, because “Cosmologists have contemplated the idea of baby universes for many years, but we do not understand the birthing process.” Goo-gol, this is getting too weird. Time out. On second thought, would a time-out act the same in a domain where time flows backward? Growing younger till you become a romantic thought in your parents’ minds sounds kind of cool.Readers may recall that in March, Nature printed an article by a cosmologist who seriously questioned a bedrock of cosmological assumptions, the Copernican Principle (03/15/2008). Is nothing in science sacred? For a revealing article on the feeble state of modern cosmology, see what Michael J. Disney wrote last fall for Sigma Xi American Scientist. He described big bang cosmology as not a single theory but a structure of five layers held together with the “ugly bandages” of inflation, dark matter and dark energy. “A skeptic is entitled to feel that a negative significance, after so much time, effort and trimming, is nothing more than one would expect of a folktale constantly re-edited to fit inconvenient new observations,” he charged. The real problem, he ended (quoting historian of science Daniel Boorstin) is not ignorance but the “illusion of knowledge.”It’s sad that Carroll has retreated into the darkness after asking such good questions back in 05/11/2006. He could have been heaven-bound by now by logically thinking through the evidence from fine-tuning for a Creator, but is now wallowing in his intellectual vomit. A mind is a terrible thing to waste. If you have been led down the primrose path in your education to believe that science is all about discovering the truth and making steady progress toward understanding reality, get real. No one can properly reason about reality without the preconditions for intelligibility provided by guidance from an eternal, timeless, omniscient, omnipotent and righteous source. Fortunately, that has been revealed to us by the only One who knows what is real. Come to the light.(Visited 21 times, 1 visits today)FacebookTwitterPinterestSave分享0
The mortal remains of the CRPF personnel killed in an audacious terror attack in Jammu and Kashmir’s Pulwama, will be sent to their homes across the country this afternoon, officials said on Friday. While a majority of the 37 bodies have been identified, some of them have been mangled beyond recognition. A home ministry official said arrangements have been made to hand over the bodies to the families. Home Minister Rajnath Singh, who is visiting Jammu and Kashmir to take stock of the situation in the wake of the terror attack, Governor Satya Pal Malik, DG of CRPF R R Bhatnagar will pay their last respect to the departed souls in Srinagar before the bodies are flown out of the state. At least 37 CRPF personnel were killed and five injured on Thursday in one of the deadliest terror attacks in Jammu and Kashmir when a Jaish suicide bomber rammed a vehicle carrying over 100 kg of explosives into their bus in Pulwama on Thursday. More than 2,500 Central Reserve Police Force personnel, many of them returning from leave to rejoin duty in the Valley, were travelling in the convoy of 78 vehicles when they were ambushed on the Srinagar-Jammu highway at Latoomode in Awantipora in south Kashmir around 3.15 pm. The Pakistan-based Jaish-e-Mohammed (JeM) terror group has claimed responsibility for the attack that took place about 20 km from Srinagar, officials said.
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