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  1. John G. Cramer, arXiv:Quant-Ph/0508102v1 14 Aug 2005.
    The transactional interpretation of quantum mechanics is applied to the “interaction-free” measurement scenario of Elitzur and Vaidman and to the Quantum Zeno Effect version of the measurement scenario by Kwiat, et al. It is shown that the non-classical information provided by the measurement scheme is supplied by the probing of the intervening object by incomplete offer and confirmation waves that do not form complete transactions or lead to real interactions.
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  2. John G. Cramer, Anti-Gravity and Anti-Mass.
    One of the great and persistent technological dreams of science fiction has been the invention which would nullify or reverse the force of gravity. H. G. Wells in The First Men in the Moon did it in 1901 with Cavorite, a substance which shields objects behind it from gravitational lines of force. James Blish in the Cities in Flight series used the Spindizzy, a device which converts rotation and magnetism into gravity fields and forces. And, of course, "floaters", "null-g speeders" (...)
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  3. John G. Cramer, Antimatter in a Trap.
    This AV Column is about the Universal Solvent of modern physics which we call antimatter, and about a bottle in which it can be and has been kept. However, before getting to the hardware I want to talk about antimatter as it relates to the fundamental symmetries of the universe.
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  4. John G. Cramer, Antigravity II: A Fifth Force?
    Then, as soon as my column was safely submitted, hot new results on antigravity appeared. The lead article in the January 6, 1986 issue of Physical Review Letters had the unassuming title: "A Reanalysis of the Eötvös Experiment" by E. Fischbach, et al. Two days later the New York Times ran an article with the headline: "Hints of Fifth Force in Universe Challenge Galileo's Findings" describing the importance of Fischbach's work. Peculiar experimental results from terrestrial gravity measurements and from the (...)
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  5. John G. Cramer, A Stroll Through the Lyman-Alpha Forest.
    As the author of these columns describing cutting edge physics and astronomy, I get quite a few letters and E-mail from readers who are more interested in “over-the-edge physics and astronomy”. One recurring theme is various alternatives to the standard model of Big Bang cosmology. Perhaps the universe is not expanding; it’s just that light “gets tired” on its path from far away and loses some of its energy. Perhaps quasars are closer than we think, particularly since some of them (...)
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  6. John G. Cramer, A Visit to Virtual Seattle.
    Last Saturday I made my first journey into virtual reality . I walked with giant strides around a city called Seattle. I leaped the Columbia Center, the tallest building in the city, with a single bound. I dove beneath the surface of Puget Sound and watched a pod of whales heading north toward Canada. I hovered above the Space Needle, then dropped inside to enjoy its panoramic view and to examine its structural details. I raced a Washington State ferry across (...)
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  7. John G. Cramer, BOOMERanG and the Sound of the Big Bang.
    Two years ago, astrophysicists studying Type Ia supernovas discovered that our universe is a much stranger place than we had imagined, with invisible vacuum energy accelerating its expansion. (See my column about this in the May-1999 Analog.) However, new astrophysical observations from the BOOMERanG experiment (Balloon Observations Of Millimetric Extragalactic Radiation and Geomagnetics), a balloon-borne cryogenic microwave telescope measurement that flew at an altitude of about 24 miles over the Antarctic, indicate that our universe is also rather ordinary, in that (...)
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  8. John G. Cramer, CERN in Transition.
    to energies of 160 GeV/nucleon, a total energy of 33.3 TeV (3.33 × 1013 electron volts) for each lead nucleus. Now, with a week of beam time remaining, we are working very hard and the experiment is beginning to collect good data. In this column, I want to describe the situation here at CERN. I'll return to the experiment after that.
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  9. John G. Cramer, Decryption and Quantum Computing: Seven Qubits and Counting.
    Alternate View Column AV-112 Keywords: quantum mechanics entangled states computer computing 7 qubits prime number factoring Schor algorithm NMR nuclear magnetic resonance fast parallel decryption coherence wave-function collapse many-worlds transactional interpretation Published in the June-2002 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 12/19/2001 and is copyrighted ©2001 by John G. Cramer.
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  10. John G. Cramer, Dinosaur Breath.
    The largest flying creature alive today is the Andean condor Vultur gryphus. At maximum size it weighs about 22 pounds and has a wingspread of about 10 feet. But 65 million years ago in the late cretaceous period, the last age of dinosaurs, there was another larger flying animal, the giant pterosaur Quetzalcotalus. It had a wingspread of over 40 feet, the size of a small airplane. Other pterosaurs were also quite large. The pteranodons of the late jurassic period, the (...)
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  11. John G. Cramer, FTL Photons.
    Albert Einstein taught us that c, the speed of light in vacuum, is nature's ultimate speed limit, the highest speed at which matter, energy, and information can travel through space-time. In several AV columns I've discussed ways for getting around this annoying natural law, the law that SF writers and fans most wish to violate. Two AV columns discussed the possibility of getting around the lightspeed limit by popping through a trans-spatial wormhole shortcut. See [ Analog-6-89, "Wormholes and Time Machines"] (...)
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  12. John G. Cramer, "Goldilocks" Gleise 581g: A Fairytale?
    In October-2010 the headlines of the science press were dominated by the announcement of the discovery of a “Goldilocks Planetâ€, Gleise 581g, which has a mass not too different from that of the Earth and has an orbit squarely in the middle of the habitable zone of its parent star. It was supposed to be not too hot, not too cold, but just right for the evolution of life. Steven Vogt of UC Santa Cruz, the lead author of the paper, (...)
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  13. John G. Cramer, Humans and Estimating Probability.
    We human beings have evolved with brains that have amazing capabilities for rational thought, pattern recognition, judgment, creativity, and imagination, none of which can be readily duplicated by the best computer simulations. However, there is one area, in which the human brain is sadly lacking: the ability to accurately assess probabilities and act on these assessments. The successes of lotteries, Las Vegas, and tribal casinos provide ample evidence that when it comes to estimating the odds and acting accordingly, we humans (...)
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  14. John G. Cramer, Light in Reverse Gear I.
    The purpose of this AV Column is to describe a physical paradox involving what seems to be an loophole in a well established physical law, the famous Second Law of Thermodynamics. The 2nd Law states that the amount of disorder (entropy) always either increases or remains constant for any isolated system of particles, whether they are gas molecules or light photons. An yet, as we will see, laser physicists seem to have provided us with a way of making the 2nd (...)
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  15. John G. Cramer, Light in Reverse Gear II.
    The "four-wave mixer", a laser technique for reversing the motion direction of light waves so that they can be turned around and returned to their point of origin was the subject of my last Alternate View column (ANALOG, June-1985). In this AV column I want to go one step further by examining a hypothetical kind of time-reversed light wave which should actually go backward in time. As we shall see, such backward waves could be used to send information from the (...)
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  16. John G. Cramer, More About Wormholes - To the Stars in No Time.
    This column is a followup to a previous Alternate View column [Analog, June-'89] about "wormholes", faster-than-light travel, and time machines, which was based on a spectacular theoretical breakthrough in general relativity. It described how a sufficiently advanced civilization might construct a stable wormhole (a curved-space shortcut between one region of space and another) and use it both for faster-than-light travel and for time travel, with no laws of physics violated in the process except causality (the principle that a cause must (...)
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  17. John G. Cramer, Millimeter Gravity and the Superstring Wall.
    Why is gravity so weak? Why are the color forces between quarks so strong? In the standard model of particle physics, why are there so many different energies at which distinct fundamental forces are supposed to "unify", and what determines these widely separated energies? The answers to these questions may be provided by extra dimensions curled into loops a millimeter around. In other words, our universe may be only a millimeter across, in directions we are not yet able to perceive. (...)
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  18. John G. Cramer, News From CyberSpace: VR and Hypertext.
    I live in Seattle, the city which last Fall was host to two major international conferences of interest to science fiction readers: The Annual International IEEE Symposium on Virtual Reality (VRAIS- 93) and The 5th ACM Conference on Hypertext (Hypertext-93). I was able to attend both conferences, and I'll use this column to provide an overview of what I learned there.
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  19. John G. Cramer, Other Universes II.
    My previous Alternate View column (ANALOG 9/84) described the widely accepted "inflationary scenario" of modern cosmology in which our Universe is just one among very many "bubble universes", all popping out of the general medium of the Big Bang like bubbles forming in a glass of beer. Somewhere perhaps there are many universes more or less like ours, some very similar to and others radically different from the universe we call "home".
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  20. John G. Cramer, Physics Goes Underground.
    If you measured the radiation present in our environment with sufficient sensitivity, you would find that the Earth is a rather radioactive place. Radon (half-life 3.82 days), a radioactive inert gas that decays by emitting energetic 8 MeV alpha particles, is..
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  21. John G. Cramer, Quantum Nonlocality and the Possibility of Superluminal Effects.
    EPR experiments demonstrate that standard quantum mechanics exhibits the property of nonlocality , the enforcement of correlations between separated parts of an entangled quantum systems across spacelike separations. Nonlocality will be clarified using the transactional interpretation of quantum mechanics, and the possibility of superluminal effects (e.g., faster-than-light communication) from nonlocality and non-linear quantum mechanics will be examined.
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  22. John G. Cramer, Quantum Time Travel.
    The territory of time travel has, from the days of H. G. Wells to the mid-1980's, been the exclusive province of writers of science fiction and fantasy. SF critics have even argued that time travel stories are so scientifically unlikely that they should be considered fantasy, not science fiction.
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  23. John G. Cramer, Real Nuclear Fusion on a Tabletop.
    In the December-1989 issue of Analog, I wrote an AV Column entitled “Cold Fusion, Pro-fusion, and Con-fusion” that described and gave my opinions about the recently announced “discovery of cold fusion” by Stanley Pons and Martin Fleischmann. These University of Utah electro-chemists claimed that by electrolyzing D2O (heavy water) on a tabletop, they had produced the nuclear fusion of deuterium (mass-2 hydrogen) nuclei..
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  24. John G. Cramer, Report on Nanocon.
    Nanocon 1: The First Northwest Conference on Nanotechnology was held at the University Plaza Hotel in Seattle, Washington, on February 17-19, 1989. The conference was sponsored by the Seattle Nanotechnology Study Group and the University of Washington Student Nanotechnology Study Group. This AV column is a report on the conference.
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  25. John G. Cramer, Recent Results.
    This Alternate View column marks three milestones: This is the 3rd anniversary of my start as an AV columnist for Analog, this is the 20th AV column I've written, and it is also the 7th anniversary of my first publication in Analog. I enjoy writing these columns on scientific subjects, but it can be frustrating. Science is continually changing as new experimental results and observations are made, as new ideas and theories are conceived and old ideas are rejected. Often by (...)
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  26. John G. Cramer, Super-Atoms and Mystery Particles.
    The path to a new discovery in physics is often a very twisted one. The subject of this Alternate View column is an example of this process. A major accelerator, built with with the prospect of discovering super-heavy elements, is now being used in an experiment to produce "super-atoms" with very large electric fields, and this work has quite unexpectedly revealed what looks like a new and mysterious particle. It is reminiscent of the SF of the 1930's where one of (...)
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  27. John G. Cramer, Searching for MACHOs.
    On a mountain top on a clear moonless night the brilliant stars strewn across the sky press down almost oppressively, the Milky Way so full of them it seems about to burst. And yet, we have been learning in the past decade that the visible matter of the universe, the stars that we see, represent only a tiny fraction, perhaps less than one part in 200, of the mass of the universe. The question of what the remainder of the universe (...)
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  28. John G. Cramer, Stretch Marks of the Universe.
    This column is about the apparent quantization of cosmological red-shifts, the persistent astronomical observation that the red-shifts and velocities of distant galaxies are not randomly distributed but rather grouped in clumps of similar values. About eight years ago I had considered an AV column on this mysterious phenomenon, but after looking at the data then available I decided against it. As an experimental physicist I've seen too many "structures" in poor-statistics data that vanished as the statistics improved. Over the years, (...)
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  29. John G. Cramer, Science Policy: The Parable of the King and the Harvest.
    I'm an experimental physicist. The basic physics research I do is funded primarily by the U. S. Government. As I write this, it is less than two weeks before the 1993 Presidential Inauguration. The new Clinton Administration is still of an unknown quantity. A new Presidential Science Advisor with excellent qualifications, Dr. John H. Gibbons, has just been appointed, but little is know about the science policies of the new administration.
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  30. John G. Cramer, Squeezing the Vacuum.
    This column is about a new development in the theory of wormholes. At Vanderbilt University, David Hochberg and Thomas W. Kephart have discovered that gravity itself can produce regions of negative energy. Within these regions, we may conjecture, stable wormholes may form naturally, particularly during the early Big Bang. A wormhole is a geometrical shortcut in curved space-time with the topology of a cup handle which, in principle, allows movement from one point in space-time to another without the necessity of (...)
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  31. John G. Cramer, "Texas" in Munich, Part 1: Closing in on the Constants of the Universe.
    This year I am on sabbatical at the Max Planck Institute for Physics in Munich, Germany, which by a happy coincidence was also the site of the 17th Texas Symposium on Relativistic Astrophysics held here two weeks ago (December 12-15, 1994). I was able to attend the Symposium, to learn quite a bit about the present state of astrophysics, and to contribute a paper co-authored by SF writers Forward, Benford, and Landis and wormhole theorists Visser and Morris [see my recent (...)
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  32. John G. Cramer, The Plane of the Present and the New Transactional Paradigm of Time.
    The plane of the present is a concept that is useful for discussing the various paradigms of time. Here by ‘plane of the present’ we mean the temporal interface that represents the present instant and that forms the boundary between the past and the future. We use the geometrical term ‘plane’ to indicate an extended surface in the space-time continuum, as opposed to a ‘point’ on some time axis. This point/plane dichotomy is intended to raise issues of extension and simultaneity (...)
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  33. John G. Cramer, The Tachyon Drive: Vex = Infinity with Eex =.
    Light speed, c = 3 × 108 meters per second, is the ultimate speed limit of the universe. The welltested physics orthodoxy of special relativity tells us that nothing can go faster than c. When any massive object with rest mass M (taken to be in energy units) has velocity v=c (or relativistic velocity ß = v/c = 1), the object's mass-energy becomes infinite. This is because the relativistic..
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  34. John G. Cramer, Warm Superconductors.
    I'm sure you know the plot: a lost magical formula has eluded the wisest practitioners of the arcane art down through the ages. Now a cabal of young upstarts, with disdain for conventional wisdom and working against all odds, discovers the key ingredients that make the magic spell work, with spectacular results.
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  35. John G. Cramer, Connecting Gravity with Electricity.
    Gravity is an extremely weak force . Consider two spheres that are close together, each with one kilogram of mass and one coulomb of electric charge, i.e., one unit each of charge and mass in Standard International Units. There will be electrical repulsion pushing them apart and gravitational attraction pulling them together, but which is bigger? It’s no contest: the electric force between these spheres is 1.35 x 1020times stronger than the gravitational force. But perhaps this difference is so large (...)
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  36. John G. Cramer, Opus 150: Dark Forces in the Universe.
    This column is a milestone. In 1983, while I was on a one year sabbatical at the Hahn Meitner Institute for Nuclear Physics in what was then West Berlin, I received a letter from Stan Schmidt informing me that Jerry Pournelle had decided that he no longer wished to be an Alternate View columnist for Analog and asking if I was interested in taking over as the AV columnist and “alternating” with G. Harry Stine.
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  37. John G. Cramer, Radioactive Decay and the Earth Sun Distance.
    About 22 years ago, the physics world was briefly rocked by claims of evidence for a new “5 th force”, based on reanalysis of data from an early 20 th century experiment. Baron Roland von Eötvös, a Hungarian nobleman, had performed extensive measurements of the correlation between inertial mass and gravitational mass and published them in 1922. The lead article in the January 6, 1986 issue of Physical Review Letters had the unassuming title: "A Reanalysis of the Eötvös Experiment" by (...)
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  38. John G. Cramer, Super Heavy Neutrinos: Who Ordered That?
    Neutrinos are very peculiar particles. About 610 trillion neutrinos produced by the sun are passing through your body in the second it takes to read this line. If it is night where you are, the neutrinos from the sun are passing through the earth in order to reach you. Because neutrinos have no electric charge and little or no mass, they interact with matter only through the two weakest forces, gravity and the weak interaction. They can pass through solid matter (...)
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  39. John G. Cramer, Two New Kinds of Wormholes.
    Wormholes are shortcuts through space time, constructs of general relativity (GR) that appear to offer a physics foundation for faster than light travel and even for travel back in time. They first appeared in the physics literature in 1935, when Albert Einstein and his colleague Nathan Rosen discovered that implicit in general relativity is a tunnel like structure in the topology of space time connecting two separated regions. Einstein and Rosen were actually trying to explain fundamental particles like electrons and (...)
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  40. John G. Cramer (1988). An Overview of the Transactional Interpretation. International Journal of Theoretical Physics 27 (227):1-5.
    The transactional interpretation of quantum mechanics is summarized and various points concerning the transactional interpretation and its relation to the Copenhagen interpretation are considered. Questions concerning mapping the transactional interpretation onto the Copenhagen interpretation, of advanced waves as solutions to proper wave equations, of collapse and the quantum formalism, and of the relation of quantum mechanical interpretations to experimental tests and results are discussed.
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  41. John G. Cramer (1988). Velocity Reversal and the Arrows of Time. Foundations of Physics 18 (12):1205-1212.
    Agendanken experiment is proposed for distinguishing between two models accounting for the macroscopic arrow of time. The experiment involves the veloeity revesal of components of an isolated system, and the two models give contrasting predictions as to its behavior.
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  42. John G. Cramer (1986). The Transactional Interpretation of Quantum Mechanics. Reviews of Modern Physics 58 (3):647-687.
    Copenhagen interpretation of quantum mechanics deals with these problems is reviewed. A new interpretation of the formalism of quantum mechanics, the transactional interpretation, is presented. The basic element of this interpretation is the transaction describing a quantum event as an exchange of advanced and retarded waves, as implied by the work of Wheeler and Feynman, Dirac, and others. The transactional interpretation is explicitly nonlocal and thereby consistent with recent tests of the Bell inequality, yet is relativistically invariant and fully causal. (...)
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  43. John G. Cramer (1983). The Arrow of Electromagnetic Time and the Generalized Absorber Theory. Foundations of Physics 13 (9):887-902.
    The problem of the direction of electromagnetic time, i.e., the complete dominance of retarded electromagnetic radiation over advanced radiation in the universe, is considered in the context of a generalized form of the Wheeler-Feynman absorber theory in an open expanding universe with a singularity atT=0. It is shown that the application of a four-vector reflection boundary condition at the singularity leads to the observed dominance of retarded radiation; it also clarifies the role of advanced and retarded waves in the emission (...)
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  44. John G. Cramer, Wormholes and Time Machines.
    Science fiction writers, to avoid undue delays in the story's plot line, need a way of beating the speed of light speed limit of the universe. Most readers of this magazine are familiar with the gimmicks that have been used for faster than light travel: warp drives, detours through hyperspace, matter to tachyon conversion, trans spatial jumps, and dives past the singularity of a rotating black hole. But perhaps the faster than light mechanism which has the best credentials in orthodox (...)
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