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)

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 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)

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)

Alternate View Column AV-02 Keywords: cosmology, bubble, universe, inflation Published in the September-1984 issue of Analog Science Fiction & Fact Magazine; This column was written and submitted 2/10/84 and is copyrighted ©1984, John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

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.

Alternate View Column AV-38 Keywords: special relativity, twin paradox, time dilation, starship, Einstein, Lorentz factor Published in the March-1990 issue of Analog Science Fiction & Fact Magazine; This column was written and submitted 8/20/89 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.

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.

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.

It’s perhaps natural to think that our universe should be more or less the same in all directions, once we average out the lumpiness of stars, galaxies, galactic clusters, superclusters, etc. However, there’s a growing body of evidence suggesting that this presumption is not true. There is now a strong suspicion that our universe may contain a gaping “hole” located in the constellation Eridanus. This all started several years ago with the observation that there was a pronounced “Cold Spot” in (...) the data from the Wilkinson Microwave Anisotropy Probe (WMAP) that produced space-based measurements of the cosmic microwave background (CMB) left behind about 400,000 years after the Big Bang. (shrink)

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".

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 (...) physics is the wormhole, also known as a Schwartzschild wormhole or an Einstein Rosen bridge. (shrink)

Many works of science fiction, for example those of David Brin, Larry Niven, and Poul Anderson, assume that our galaxy is populated by many intelligent alien species that we will eventually contact for cooperation, competition, or perhaps combat. Isaac Asimov, on the other hand, assumed in his Foundation Series that humanity would spread out into the empty galaxy and colonize it without encountering other intelligent species.

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)

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 (...) proton. They suggested that if lines of electric flux were threaded through such a structure, the flux would be trapped and one end would appear to be an isolated positive charge and the other end would appear to be a negative charge. Later, however, general relativity was used to calculate the masses of such “particles” and it was realized that they would be have a mass of at least a few micrograms, far heavier than the mass of an electron or proton. (shrink)

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 (...) precede its effects). (shrink)

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.

This column is about recent evidence from the Super Kamiokande detector in Japan indicating that at least one of the three known neutrino flavors, the mu-neutrino, has a non-zero rest mass. To put this result in the proper context, I'll briefly review parts of the standard model of particle physics.

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)

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)

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)

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)

unlikely name of Sanduleak -69 o202 had exploded, becoming type II supernova SN1987A. The discovery was broadcast to a data-hungry world, and the astronomy/astrophysics community has been in an uproar ever since. Sanduleak -69 o202 before exploding had a mass 15-20 times greater than that of our sun and was located in the Large Magellanic Cloud, a sort of suburb of our galaxy some 160,000 light years distant. To the despair of residents of North America, SN1987A is visible only in (...) the southern hemisphere. A friend just back from Argentina tells me that it's still quite visible there and is about as bright as the stars of the Southern Cross constellation. (shrink)

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)

Alternate View Column AV-81 Keywords: Alcubierre Warp Drive FTL spacewarp solution Einstein's equations general relativity Published in the November-1996 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 4/15/96 and is copyrighted ©1996 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

Alternate View Column AV-101 Keywords: quantum mechanics paradox Mach-Zender interferometer interaction free measurement test Published in the June-2000 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 12/19/99 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.

Alternate View Column AV-62 Keywords: quantum nonlocality entangled states recreation communication Published in the December-1993 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 5/17/93 and is copyrighted ©1993 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

Alternate View Column AV-06 Keywords: dimensions, Kaluza-Klein, compactified, string theory Published in the April-1985 issue of Analog Science Fiction & Fact Magazine; This column was written and submitted 10/1/84 and is copyrighted © 1984, John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

This page now has an access count of: Alcubierre Warp Drive (see the 11/96 issue of Analog). The Alcubierre Warp Drive is a distortion of space, a solution to the equations of general relativity that forms a sphere of flat space surrounded by a warped-space "bubble". At the front edge of the bubble, space is contracting (like a collapsing black..

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.

On of the earliest triumphs of quantum mechanics, when the theory was first formulated in the 1920s, was George Gamow's use of quantum tunneling to explain the phenomenon of alpha decay. It was well known then that certain heavy radioactive nuclei, including radium then widely used for glow-in-the-dark clock dials, would spontaneously and unpredictably spit out an energetic helium-4 nucleus (also called an alpha particle) and be transformed into a new lighter nucleus with two fewer nuclear charges. Alpha radioactivity is (...) often very improbable, and this takes the form of alpha-decay half-lives measured in thousands or even millions of years. The question was, how and why did the alpha particle escape its prison in the nucleus, where it should have been tightly and permanently bound? (shrink)

Alternate View Column AV-91 Keywords: dark matter WIMPs weakly interacting massive particles detection DNA eV energy deposition Published in the September-1998 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 02/20/98 and is copyrighted ©1998 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

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)

Alternate View Column AV-24 Keywords: cosmic string, oscillation, gravity wave, spiral galaxy Published in the January-1988 issue of Analog Science Fiction & Fact Magazine; This column was written and submitted 6/26/87 and is copyrighted © 1987, John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.

The Large Hadronic Collider (LHC), which is to be the world’s highest energy particle accelerator, is currently being constructed at the CERN laboratory in Geneva, Switzerland. The machine was designed to be high enough in energy to produce a completely new type of particle, the Higgs boson, which is considered to be the missing puzzle-piece in the Standard Model of particle interactions. According to current theoretical thinking, it is the Higgs particle that gives mass to all the other particles, quarks, (...) leptons, etc., in the current bestiary of fundamental particles. (shrink)

I'm Professor of Physics at the University of Washington in Seattle . I do basic research in ultra-relativistic heavy ion physics with the STAR experiment, using the RHIC facility at Brookhaven National Laboratory, colliding gold nuclei to produce systems that look something like the first microsecond of the Big Bang. I do not work much in cosmology and astrophysics, although I've published a paper or two in those areas, but I do write a bi-monthly science column for Analog Science Fiction/Fact (...) Magazine . One of my columns was entitled BOOMERanG and the Sound of the Big Bang " and was published in the January-2001 issue of Analog. It described the then-recent Antarctic balloon flight that mapped the small-angle temperature variations of the cosmic background radiation. Following the lead of the scientists involved in the project, I described the temperature variations they observed as, in effect, a recording of the "sound of the Big Bang" when the universe was 376 thousand years old. (shrink)

A recent breakthrough has moved the concept of a "warp drive" another step along its path from a fictional SF prop-idea to a well founded physics concept that might one day be realized. This improvement on the Alcubierre warp drive was devised by general relativity theorist Chris Van Den Broeck of the Catholic University of Leuven in Belgium. He has eliminated seemingly insurmountable problems with the Alcubierre warp-drive scheme. His improvement employs topological gymnastics to keep the interior of the warp (...) bubble large while making its external surface very small. But before describing Van Den Broeck’s work, I’ll summarize the Alcubierre warp drive concept itself, first featured in my column (#81) in the November-‘96 Analog. (shrink)

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)

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.

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)

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 (...) Ephriam 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 possible implications of Fischbach's work. (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)

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 (...) is made of is called the Dark Matter Problem. It is one of the most vexing in modern physics. (shrink)

Alternate View Column AV-108 Keywords:Bose Einstein condensate force reversal collapse bounce supernova neutron star remnant Published in the October-2001 issue of Analog Science Fiction & Fact Magazine ; This column was written and submitted 4/6/2001 and is copyrighted ©2001 by John G. Cramer. All rights reserved. No part may be reproduced in any form without the explicit permission of the author.