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. (...) A detailed comparison of the transactional and Copenhagen interpretations is made in the context of well-known quantum-mechanical Gedankenexperimenre and "paradoxes." The transactional interpretation permits quantum-mechanical wave functions to be interpreted as real waves physically present in space rather than as "mathematical representations of knowledge" as in the Copenhagen interpretation. The transactional interpretation is shown to provide insight into the complex character of the quantum-mechanical state vector and the mechanism associated with its "collapse." It also leads in a natural way to justification of the Heisenberg uncertainty principle and the Born probability law (P = ii iij*), basic elements of the Copenhagen interpretation. (shrink)

This book shines bright light into the dim recesses of quantum theory, where the mysteries of entanglement, nonlocality, and wave collapse have motivated some to conjure up multiple universes, and others to adopt a "shut up and calculate" mentality. After an extensive and accessible introduction to quantum mechanics and its history, the author turns attention to his transactional model. Using a quantum handshake between normal and time-reversed waves, this model provides a clear visual picture explaining the baffling experimental results that (...) flow daily from the quantum physics laboratories of the world. To demonstrate its powerful simplicity, the transactional model is applied to a collection of counter-intuitive experiments and conceptual problems. (shrink)

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 (...) of very weakly absorbed radiation such as neutrinos. (shrink)

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 (...) and to examine the degree to which these are meaningful concepts from various physical viewpoints. We will show by example in the present work that the plane of the present is a pivotal concept that offers considerable power in differentiating between various views of the nature of time. The concept of time within the main stream of physics thinking has followed a rather convoluted path over the past three millennia. Anticipating the modern motion picture, Zeno of Elea (c.490-c.430 B.C) questioned whether time should appropriately be viewed as a continuously flowing river, or should more properly be considered as a rapid sequence of stop-motion ‘freeze-frames’, in effect rendering geometrical each instant as a separate infinitesimal point on the line of time. Adopting this view, he asked how physical motion could occur. He argued paradoxically that motion is not possible, since it appears to happen only between the frozen frames of time instants.1 From the viewpoint of Zeno, the plane of the present would be simply the last and most recent in this sequence of freeze-frames. It would be that frozen instant, spanning the universe, which changes progressively as the instant we call ‘now’ becomes the frozen past and future possibility freezes into the ‘now’ of present reality. We note that the plane of the present as a concept does not resolve the arrow paradox that Zeno raised. It only provides a way of thinking about it. (shrink)

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.

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.

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.

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.

This column is about a new alternative to standard Big Bang cosmology that reaches back in time to the era before the Big Bang in an effort to remove some of the arbitrary assumptions from the model. It's in part the work of Gabriele Veneziano, a theorist at CERN, and it is called pre-Big-Bang cosmology. We'll begin by reviewing the standard scenario of the origin of the universe.

This column is about experimental tests of the various interpretations of quantum mechanics. The question at issue is whether we can perform experiments that can show whether there is an "observer-created reality" as suggested by the Copenhagen Interpretation, or a peacock’s tail of rapidly branching alternate universes, as suggested by the Many-Worlds Interpretation, or forward-backward in time handshakes, as suggested by the Transactional Interpretation? Until recently, I would have said that this was an impossible task, but a new experiment has (...) changed my view, and I now believe that the Copenhagen and Many-Worlds Interpretations (at least as they are usually presented) have been falsified by experiment. (shrink)

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.

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" (...) and "grav sleds" have abounded as techno-props in science fiction stories for many years. (shrink)

Alternate View Column AV-97 Keywords: super-lasers space molecules atom lasers 4-wave mixers direct CP violation matter-antimatter asymmetry K0 mesons Published in the October-1999 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 03/28/99 and is copyrighted ©1999 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

My interest in the physics of space station gravity developed because last year Vonda McIntyre was writing a book with a space station setting, and she asked my advice. The book, Barbary, is about a teenager who leaves Earth to live in a space station with spin-generated gravity. I helped Vonda in a very minor way by identifying the physical effects that the heroine would experience in that environment. What's it like to ride an elevator in a space station? How (...) would a ball game look if it were played there? If you woke up in a strange location, what simple tests would tell if you were in a rotating space station rather than at rest on the ground? And so on ... I found that there are some interesting side-effects of artificial gravity, perhaps well known to NASA experts but obscure to the rest of us. And I was surprised to find that some recent SF hasn't been too accurate in describing the space habitat environment. (shrink)

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.

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 (...) behavior of "strange" K-mesons (kaons) had been explained by a new theory proposing a "hypercharge" force, a new fifth force of nature which is gravity-like but which repels rather than attracting nearby masses. This new antigravity force is the subject of this AV column. (shrink)

Keywords: geology instrument probe Earth interior crust magma core crack underground nuclear explosion molten iron China Syndrome melting rock Published in the December-2003 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 06/22/2003 and is copyrighted ©2003 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

This Alternate View column is about two new reports of possible antigravity breakthroughs. Perhaps, like the Dean Drive, they will prove to be bogus. But the subject continues to have interesting SF implications, and the payoff, if an antigravity route out of Earth's gravity well could be found, would be enormous.

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 (...) appear to be linked to closer galaxies. Perhaps relativity is wrong, and it’s the speed of light that is different in different parts of the universe or changing with time. Perhaps quasars are the tailpipes of nearby alien spaceships, and they have such large red shifts because we only see them when they are moving away from us. And so on…. (shrink)

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 (...) the Sound from Seattle to Bremerton. I caught up with it just as it approached the Bremerton dock and was able to watch the docking operation from a perch on the roof of the bridge. Then I flew back across the Sound and peered down into the Kingdome, looking in vain for a winning team. Finally, I pointed my magic glove across the Sound to the Olympic Peninsula, flew there, and examined a group of towering snow-capped peaks from all angles. I did all of this without leaving a small building on the campus of the University of Washington. (shrink)

Yet normal particle interactions produce matter and antimatter in equal amounts. If matter and antimatter in the early universe had been in perfect balance, they would long since have been annihilated out of existence, leaving behind a universe of photons and a few electrons. We would not be here to study such a universe, since our very existence depends on the gross excess of matter over antimatter now present. Where did the matter come from? What happened in the early stages (...) of the Big Bang that produced the contemporary dominance of matter? (shrink)

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 (...) its space is maximally flat. The term “flat” as used here means that the space of our universe is neither positively curved like a ball or negatively curved like a potato chip. It appears that in our universe, the tendencies of space toward positive curvature from gravitational attraction and towards negative curvature from expansion kinetic energy are precisely in balance, leaving space on the average completely free of curvature. (shrink)

The "groupie" tendency of bosons has recently been demonstrated in a breakthrough experiment by Carl Wieman of the University of Colorado and Eric Cornell of the National Institute for Standards and Technology and their group. They were able to cool a gas of rubidium-87 atoms to a temperature so low that thousands of atoms coalesced into the same quantum state, forming a new state of matter called a Bose-Einstein condensate (BEC). This column is about that work.

The physics behind the limerick is that within Einstein’s special theory of relativity there is a subtle connection between faster-than-light and backwards-in-time travel. If you could do one, then in principle you could also do the other. But relativity is carefully contrived to prevent superluminal and back-in-time travel and communication.

So far this has been a lonely and unrewarding quest. New experiments occasionally come along which point to a breakdown of the Standard Model, but up to now they have invariably been proved wrong by more careful analysis or subsequent experiments with better data. A case in point is the energetic jet data from the CDF experiment at FermiLab which suggested possible substructure of the quark. (See my AV column "Inside the Quark" in the September-1996 issue of Analog.) The CDF (...) group found an unexpected excess of "jets" (clumps of energetic particles moving in the same direction) with energies above 200 GeV in their data. They found that they could not explain this excess of high energy jets using the Standard Model, as interpreted by standard theoretical procedures, and they pointed out that the data might represent new physics, possibly an indication that the quark is a composite object made of even more fundamental particles. (shrink)

Nevertheless, the problem of nuclear waste disposal is not insoluble. Good technical solutions have existed for at least 20 years, but for political reasons none has ever been implemented. This could be changing. New accelerator-based technical solutions are perhaps more politically acceptable. This column is about this emerging technology.

In this column, however, I'm not going to talk about my own experiment here, but about CERN's fast-track plans for building a new and more powerful particle accelerator, the Large Hadronic Collider or LHC. The LHC is to come into operation around 1999. It is the principal competition for the SSC, the huge U. S. accelerator presently under construction in and around Waxahachie, Texas. [See my AV column "The Coming of the SSC", Analog March, 1988 for a description of that (...) project.]. (shrink)

What perhaps you did not know is that centrifugal force is, strictly speaking, not a force at all. It is a pseudo-force. It is, in a sense, an illusion produced by changing coordinate systems. This is a slippery idea which will require some explanation. So to understand why centrifugal force is not a true physical force, let's start by considering what the true forces of nature are.

Alternate View Column AV-36 Keywords: cold fusion, deuterium, electrolysis, heavy water, Pons and Fleischmann Published in the December-1989 issue of Analog Science Fiction & Fact Magazine; This column was written and submitted 5/5/89 and is copyrighted © 1989, John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

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 (...) because Standard International Units depend on some rather arbitrary choices on the size of units. What about fundamental particles? (shrink)

to energies of 160 GeV/nucleon, a total energy of 33.3 TeV 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.

In the remote deserts of Utah, at a location selected for clear air and remoteness from the lights of civilization is the Fly's Eye, a group of "compound eye" light detectors with photomultipliers for facets. It watches the night sky for the light made by the most energetic cosmic rays as they enter the upper atmosphere. Physicists using the Fly's Eye have found an exciting new result, the upper energy limit of cosmic rays. And they have also observed something else, (...) something entering the atmosphere from the direction of the Swan. (shrink)

Last Thursday, a front page headline in the New York Times announced Astronomers' New Data Jolt Vital Part of Big Bang Theory ". Newly analyzed data from the Infrared Astronomical Satellite, the Times reported, show conclusively that these vast structures are not isolated oddities. Instead, the structures are normal features of our universe which has an intrinsic lumpiness that is far larger and more uneven than can be reconciled with the best current theories about when and how our universe formed.

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.

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 (...) classic flying dinosaurs of magazine illustrations, had a maximum wingspan of about 33 feet. (shrink)

In this AV column we will have a look at the DUMAND project, a new $10 million detector funded by the US Department of Energy for the detection of ultra-high energy neutrinos. DUMAND stands for Deep Underwater Muon And Neutrino Detector. It is now under construction in Hawaii and will come into operation in 1993-94. It is to be placed almost 3 miles deep on a level stretch of Pacific Ocean bottom about 18 miles west of Keahole Point on the (...) Island of Hawaii. Floats anchored to the ocean bottom about 40 meters apart and arranged in an octagon around a central junction point will support nine long vertical strings of sensitive light detectors. DUMAND will be connected to its land-based laboratory by bundles of fiber optics cables. AT&T will lay the cables to shore, and the US Navy's manned deep submersible DSV Sea Cliff will be used to connect, service, and repair the parts of the detector. (shrink)

Freeman Dyson has a well-deserved reputation as a truly original thinker. He helped to conceive Project Orion, a hydrogen-bomb-powered starship concept, and his name is associated with the Dyson sphere, the ultimate solar-energy based civilization. Whenever there are two conflicting opinions on a controversial technical subject, be it disarmament, nuclear power, or construction of big accelerators, Dyson can be depended upon to propose a strikingly original third opinion, always logical and well-considered, which bears little resemblance to either of the other (...) two. In the case of the space program his views stand in striking contrast to those of both the "Get humans into space at whatever cost" camp and the "Dump manned spaceflight and do space science with machines" advocates. (shrink)

For three days in April, 2005, I was a speaker and panelist at the NASA-sponsored “Physics for the rd Millennium II Conference” in Huntsville, Alabama, where twelve of us, including two Nobel Laureates, were invited to give 50-minute lectures about cutting-edge physics to an audience of NASA engineers, teachers, students, parents, and other interested attendees. In this column, I want to tell you about the work described in one of the talks, given by Dr. George Chapline of the Lawrence Livermore (...) Laboratory. (shrink)

emerging field of nanotechnology. Nanotechnology gets its name from the nanometer, a distance of 10 -9 meters or roughly the diameter of a molecule, and the term refers to the technology for structuring matter with precise control at the nanometer scale, atom-by-atom or molecule-by-molecule, to form a pre-specified pattern. In other words, nanotechnology is the general ability to build large or small structures to complex atomic specifications.

Last June I was an invited speaker at the symposium “Frontiers of Time: Reverse Causation—Experiment and Theory,” part of a meeting of the American Association for the Advancement of Science (AAAS) held on the beautiful campus of the University of San Diego. (Here, reverse causation means a violation of that most mysterious law of physics, the Principle of Causality, which requires that any cause must precede its effects in all reference frames.) I had originally intended to just talk about my (...) work on the transactional interpretation of quantum mechanics and its somewhat retrocausal aspects (i.e., back-in-time handshakes of quantum waves, etc.). However, a new idea involving signaling with nonlocal quantum processes had come my way, and I decided to present it as a retrocausal quantum paradox at the symposium. It made a big splash there, but none of the experts present could identify any problem with the proposed thought experiment or resolve the paradox. In this column I want to tell you about this causality-violating communications scheme and its possible consequences. (shrink)

Keywords: extrasolar planets Hubble telescope occulter apodization life oxygen Published in the March-2007 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 10/17/2006 and is copyrighted ©2006 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

Einstein's "spookiness" is now called nonlocality, the mysterious ability of Nature to enforce correlations between separated but entangled parts of a quantum system that are out of speed-of-light contact, to reach faster-than-light across vast spatial distances or even across time itself to ensure that the parts of a quantum system are made to match. This column is about nonlocality, and how, through Bell's theorem, the nonlocality implicit in nature has been demonstrated in the laboratory.

Alternate View Column AV-105 Keywords: superluminal faster-than-light laser pulses phase front velocity negative group velocity reshaping Published in the March-2001 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 08/19/2000 and is copyrighted ©2000 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

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"] (...) and [Analog-5-90, "Wormholes II: Getting There in No Time"]. Two others discussed the possible use the faster-than-light nonlocal handshaking implicit in quantum mechanics for FTL messages and travel. See [Analog-11-86, "The Quantum Handshake"] and [Analog-9-88, "Paradoxes and FTL Communication"]. Both of those methods, however, are beyond our present technology, and the latter is probably impossible. (shrink)

There are a number of geophysical and astrophysical problems with Burroughs' s setting. Perhaps it is pointless to complain, 75 years too late, about the "hardness" of such science fantasies, for the strong suit of Burroughs' writings always lay in their imaginative sweep, never their scientific accuracy. In the case of Pellucidar, however, Burroughs committed a blunder that sets the teeth of every physicist on edge: he assumed that gravity would pull toward the inner surface of a hollow sphere.

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, (...) was quoted (out of context) as saying, “The chances of life on the planet are 100%.†Now that some of the dust has settled concerning this reported discovery, I’d like to have a look at the work behind the announcement and consider its present status. (shrink)

This column is a milestone. It's the 100 th Alternate View column that I've written for Analog over a period of 16 years beginning in 1983. I was on a sabbatical in Berlin when Stan recruited me to write the column after Jerry Pournelle, my predecessor as AV columnist, decided to step down. The AV columns are a soapbox that was too attractive to pass up, and I've used them to promote an interst in science and to feed cutting-edge science (...) ideas, primarily in the areas of physics and astrophysics, to the readers and writers of science fiction. (shrink)

Our galaxy contains a remarkable "faster-than-light" object discovered only a few months ago by radio astronomers. The object, a blob of hot radio-emitting matter thrown off from gamma ray source GRS1915+105, was observed to separate from its larger parent object at an apparent speed of 1.25 times the velocity of light. The operant word here is "apparent". The faster-than-light separation speed (separation distance divided by time) is believed to be a consequence of the same relativistic illusion previously observed for radio (...) objects ejected by quasars. We will start with some facts about quasars. (shrink)

Curiously, in some ways gravity is also the strongest force in the universe. It always adds, never subtracts, and can build up until it overwhelms all other forces.. In normal stars gravity is balanced by heat energy from fusion reactions in the star's core. Eventually, however, the hydrogen and heavier elements fueling these reactions are used up, gravity takes over, and the star collapses in on itself. The result is a supernova explosion, which converts a sizable fraction of the star's (...) mass-energy to light, neutrinos, and gravity waves. (shrink)

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 (...) as a species are really deficient. We think that “winning streaks†are real, that slot machines are “overdue†for a jackpot, that the past pattern of random events somehow influences the odds for the next event. (shrink)