A Stardrive Interview with
Dr. Eric Davis

by
Kim Burrafato


Eric Davis did his undergraduate work at Phoenix College, Phoenix, AZ (A.A. in Liberal Arts, 1981) and the University of Arizona in Tucson (B.Sc. Physics major, Mathematics minor, 1983). He received his Ph.D. in Physics (multidisciplinary research in planetary science and astrophysics of gaseous nebulae, doctoral minor in cosmology/relativity theory) from the University of Arizona in 1991. Eric began his graduate work as a mission support and research assistant with the Infrared Astronomical Satellite group at the Steward Observatory in Tucson, AZ. He later joined the Voyager Ultraviolet Spectrometer Experiment group at the Lunar and Planetary Laboratory in Tucson where he conducted research on Jupiter's magnetosphere (dissertation on the Io Plasma Torus), the Uranus and Neptune planetary encounters, and participated on the Voyager 1 & 2 space flight operations. Eric also dabbled in work sponsored by the Air Force and Hughes Missile Systems Company on antimatter rocket propulsion research, design and testing with collaborations at the University of Arizona Nuclear Engineering Department and the Jet Propulsion Laboratory.

In 1992, Eric became an associate faculty member at Pima College in Tucson which included a term as interim director of the Arizona Astronomy Education Center. Summer professorships at Embry-Riddle Aeronautical University in Prescott, AZ and the NSF Summer Science Program at The Thacher School in Ojai, CA. followed. He was also a member of the ASUSat 1 critical design reviews at the Arizona State University Aerospace Engineering Department's NASA Space Grant Project. In 1995, Eric became Lecturer (physical and computer sciences, mathematics and space flight engineering) at the University of Maryland Asian Division. He was stationed at the USAF 8th Fighter Wing in Kunsan, South Korea and also worked at other USAF bases and Army camps in the region. In addition, Eric provided consulting and training services on classified combat theater space reconnaissance operations for US Forces Korea.

He later returned to the U.S. and accepted a job offer from the National Institute for Discovery Science in Las Vegas, NV. He is currently employed there as Director of Research, Aerospace Physics. In this capacity, Eric has participated in the NASA Breakthrough Propulsion Physics effort as an expert on traversable wormholes. Eric's technical interests also extend to Alcubierre and Krasnikov warp drive metrics, FTL anomalies in physics and zero-point energies. He has given several popular and technical talks and papers on the subject of traversable wormholes.

Eric is a Fellow of the British Interplanetary Society, senior member of the American Institute of Aeronautics and Astronautics, and member of the American Astronomical Society. He has served in the capacity of Chief Executive Officer and Chairman, as well as board director, for these and other professional engineering organizations and chapters. Eric has consulted for the U.S. Air Force and U.S. Forces Korea in South Korea, State of Arizona and City of Tucson agencies involved with aerospace defense industry. He has won national aerospace public policy awards from the American Institute of Aeronautics and Astronautics as well as awards of proclamation from the Governor of Arizona in annual celebrations of the Apollo XI landing on the Moon.

He recently attended the the Space Technology Applications International Forum(STAIF-98, in Albuquerque,NM (January 25-29, 1998). At STAIF, Eric presented a paper entitled "Interstellar Travel By Means Of Wormhole Induction Propulsion (WHIP)." In this paper, he proposed that it may be possible to create a small scale change in the space-time curvature in a laboratory setting. Davis believes this could be done using the ultra-high magnetic fields generated in a nuclear explosion. If such small scale curvature could actually be created and measured in a lab, it would be proof that space-time curvature can be engineered. That, in turn, would eventually lead to the creation of wormholes and warp drive type space propulsion.

(Eric Davis -- ED; Kim Burrafato -- KB)

KB: First on my list, is the question of time dilation. Please correct me whenever I'm wrong, but do Alcubierre type warp drives permit arbitrarily fast shipboard flight times?

ED: No! It is arbitrarily large spacecraft speeds - in the frame of stationary observers, that is.

KB: As far as I know, traversible wormholes do not get around the time dilation problem, unless one devises very complicated schemes of enginering exotic wormholes that have rapidly accelerating mouths that can effectively whip back and forth in time, while maintaining throat stability.

ED: Also incorrect!

KB: I'm not doing too well so far.

ED: Wormholes have no time dilation problem and they don't work the same as Alcubierre metric. In wormhole metrics, proper time for moving observers going through the throat and coming out the other side is the same proper time as for stationary observers outside the wormhole. No dilation is needed or is involved whatsoever.

The reason it is said is that accelerating wormhole mouths through space is just for backward time travel effects only. And then accelerating them is incorrect statement too. What one needs to do to undergo backwards time travel by going through a wormhole throat is the following: 1) Enter the wormhole mouth that has been produced closest to you, 2) Technicians on the other side must now move the mouth at their end up to the speed of light, 3) When you emerge from that end, you have emerged in the past.

Throat stability is independent of any of this activity.

KB: One can, in principle, get back to where one started, but no further back than that.

ED: Supposedly correct, but there is no proof that this is real physics. Paul Nahin, in his book, has pointed out that no physics prevents time travel (and violate causality) backwards to points earlier than when you left on your trip. Wormhole researchers don't like this point because it upsets their preconceived notions of reality and sanity in the universe. They have no physics to substantiate their fears.

KB: Of more important concern to me is the overall logical and chronological evolution of these ideas. Can it be said that the original Levi-Cevita magnetic gravity solutions to general relativity first legitimized the idea of artificially manipulating spacetime curvature?

ED: Yes!

KB: Did Thorne, Morris, Novikov, et al, then come along and extend the Levi-Cevita solution to include the possible creation of exotic matter-based traversible wormholes?

ED: No! They found, like I did, that Levi-Civita's magnetic or electric metric was NOT a wormhole solution. Morris et. al. went to another more general metric (exact) solution technique for the GR field equations. Levi-Civita's metric describes (see my paper) a position-dependent gravitational potential on a 3-space hypercylinder which can be induced by axisymmetric homogeneous magnetic or electric fields. There's no wormhole here.

KB: Years pass. Alcubierre arrives on the scene. Now things get blurred (no pun intended). Was his warp drive solution an outgrowth of the original Levi-Cevita solution, or was he extending the Thorne-Morris solutions?

ED: None of the above - no relation to wormholes. Alcubierre was strictly looking for a moving localized metric warp around a spacecraft in the spirit of Star Trek.

KB: Along comes Maccone, who shows that one can manipulate spacetime curvature with sufficiently strong static, homogeneous electro-magnetic fields--eliminating the difficult requirement of having to create exotic matter for constructing and stabilizing the wormhole (as it turns out, exotic matter may be a natural consequence of generating such ultra-high strength magnetic fields).

ED: Yes, partly. But no, in general. He came along and proposed a linear accelerator to create the magnetic field, and they produce an average of 10 Tesla only - not ultrahigh fields of 10^15 Tesla like I said. I then said, to correct him, that ultrahigh B-fields would be necessary according to the equations for generating a NON-wormhole spacetime curvature as a near-term lab experiment for NASA Breakthrough Physics Propulsion program - as a first step experiment towards manipulating spacetime in the lab. We need this small step before we can get to the step of creating a (speculative at this time) enough exotic energy in a lab to really induce a wormhole.

Maccone's analysis was wrong - there is no wormhole. My correct interpretation of Levi-Civita showed only that we have the possibility of manipulating spacetime curvature in the lab by creating a hypercylinder with position-dependent gravity field (curvature, of course) that is induced by ultrahigh B or E fields.

KB: So, Eric Davis follows by showing that current nuclear explosives technology can produce magetic fields of sufficiently high strength to produce a measurable change in spacetime curvature. In this particular case, it would be slowing down a beam of light passing through it in a laboratory setting (albeit it a rather large setting one would think). Am I close?

ED: Yes!

KB: And now for the stupid questions. Have there been any serious challenges to the Levi-Cevita solutions?

ED: Yes, mine. I wrote the challenge in my STAIF and NASA papers after consulting with Matt Visser on the issue. After reading a copy of my NASA paper, Claudio Maccone e-mailed and thanked me for correcting the mistakes in his JBIS paper and for improving and expanding on his idea of using magnetic fields in proposed laboratory experiments.

KB: What exactly is a hypercylinder?

ED: A 4-dimensional spacetime has a surface, which is induced and shaped by whatever matter-energy fields are arranged locally in that spacetime. This surface is 3-dimensional and is called, in the parlance of Riemannian geometry, a hypersurface. A 3-space hypercylinder is just the (magnetic or electric field induced) cylindrical surface created in this spacetime.

KB: Can you give a brief lay description of magnetic induction, in the sense it's being used here?

ED: Yes. Magnetic induction as performed by a wire solenoid. Just imagine a very long solenoid of length L (radius is not important), with wire wrapped (coiled) around its surface. When you put a current through the wire, you generate a magnetic induction or field per Ampere's Law.

KB: Is the recently observed "frame drag" an example of spacetime curvature in action?

ED: Yes, in a way. It's an example of spacetime being dragged around a massive body as if it were a substance (as opposed to a vacuum of nothing).

KB: I'm trying to visualize what all this would look like. We have the ship with its hypercylindrical "skin" -- I presume this hypercylinder is equivalent to a surrounding gravitational well of sorts?

ED: Yes. The gravity well is position dependent along the symmetry axis of the solenoidal B-field. You actually cannot visualize this thing because the hypercylinder is a 3-dimensional surface of the surrounding spacetime. Hard to visualize since our minds perceive 3-dimensional solids with 2-dimensional surfaces. We cannot perceive the time dimension in its entirety and independently of the other space dimensions.

KB: Where things become unclear - in TWs created either by exotic matter or ultra-high magnetic fields - is what happens at the exact moment the wormhole mouth is opened/created. I believe you're talking about a sudden 90-degree phase shift, where the hypercylinder transforms into a radial plate-like field? And how does one know when to open the mouth?

ED: Actually, what is going to happen on someone's command, is that the B-field generator is going to start stressing the cylindrical symmetry (configuration) of B-field into a radial (spherical) symmetry (configuration). This will then put the B-field tension infinitesimally larger than the energy density, thus creating the "exotic energy violation" necessary to open the wormhole.

No ideas yet on when one knows the wormhole is created. Possibly a ship navigator will look for clues in the background stars - they become suddenly blanked out around a spherical region because the wormhole is blocking the paths of background starlight. Or maybe there will be some slight repulsive gravitational stresses that could be measured for using Bob Forward's ring-laser gyros. Maybe one will need to look for strange scenary (lights, stars, etc.) coming into focus where the wormhole would be and displacing the "known background scenary" cataloged by astronomers for the location of the starship - this would be the light from "the other side" travelling thru wormhole throat and coming into our side of the universe. Thus one will see normal background stars with a spherical region of light or stars which are out of place with respect to what was orignally cataloged to be visible at the location of the wormhole. A paper to this effect has all ready been published.

As I recall, the paper "Natural wormholes as gravitational lenses" by Cramer, et. al., shows that wormholes would deflect starlight coming from behind them (not through them!) into an umbra region of zero intensity with light rays accumulating at the edges creating a rainbowlike caustic and enhanced light intensity. This would be an excellent way of looking for wormholes.

KB: What happens when we enter the mouth? While inside a wormhole, how does one navigate in the ordinary 3D sense?

ED: Navigating is not an issue! Visser (see my paper in Technical Issues section) showed that for generic traversable wormholes the symmetry conditions, flared-out mouths and asymptotic spacetime can all be thrown out. The only condition necessary to characterize ANY wormhole is the geometry at the throat. Presumably, the starship U.S.S. Sarfatti would just go through the throat from one side (of universe) and re-appear "elsewhere" on the other side, while the distance through the throat is only nanometers or angstroms. There's nothing to navigate through since you go through and come out the other side rather suddenly!

KB: What are the forces like near the wormhole mouth?

ED: Again, mouths are not necessary anymore - not a consideration for the physics at hand.

KB: Are there strong attractive tidal forces, like those near the event horizon of a black hole?

ED: Tidal forces are repulsive since it's negative energy density (rho*c^2 < tau - energy density less than stress energy) generating the gravitational spacetime curvature effect needed to open the throat. They are not strong at all since the design criteria for sending passengers through the throat without crushing them restricts the tidal forces to <= 1 gee (see, Morris and Thorne's Am. J. Phys. paper referenced in my paper). By the way, tidal forces on black hole horizons can be ZERO with NO associated spacetime curvature, e.g. flat space on horizon. They are only noticeable inside the horizon as one gets closer to the singularity.

KB: What is the relationship between wormhole length, width, and the effective distance covered after exiting?

ED: None yet. This hasn't been explored. The wormhole still could attach to another universe altogether as far as our physics knows, without experiments to guide us.

KB: If the TW isn't an already existing "primordial macroscopic wormhole," but rather engineered, how do we "aim" it in the direction we want to exit from?

ED: Good question! We don't know the answer yet.

KB: When we travel through a TW, are we going to a different place and time in THIS universe?

ED: Different place, same time!

KB: Or, are we going to a different place and time in a DIFFERENT universe?

ED: Different place in a different universe, yes as I said a bit earlier. But time flow is still the same since generic wormholes don't alter proper time or distance.

KB: In other words, does TW travel neccessitate branching in a multiverse scenario?

ED: Possibly! But this will require further theoretical development and experiments to be sure.

KB: Assuming we're using TWs as spacetime shortcuts, then there shouldn't be any problems with time travel paradoxes, and having to engineer exotic wormholes with things like rapidly accelerating mouths etc. We're simply leaving in the here and now, to go somewhere else when. When we come back, it will be a different when, but it will be the same where we left. Obviously, it would be desirable to as closely match your actual shipboard time elapsed as possible to that of those back home. Again, we're back to the time dilation problem.

ED: You have this incorrect. As I've said above and in my answers given to some of your earlier questions, wormhole metrics (generic and specific) are shown to NOT alter proper time between moving and stationary observers - there is no time dilation problem in wormhole physics.

Only in wormholes which have one mouth accelerated up to the speed of light, will there be a (backwards) time paradox, and no special relativistic foward time paradox. However, this is no longer clear since Visser showed that generic wormholes do not need or even have mouths.

KB: I think that's enough for now. Oh, one other thing. I was discussing with Jack Sarfatti the idea of a universe riddled with hitherto unseen primordial macroscopic wormholes (PMWs). He thinks such a scenario would go a long way in explaining the missing mass. If there were such a thing, wouldn't there be some kind of subtle, anomalous gravitational lensing effects that we might be able to detect?

ED: Yes! As I said earlier about when one determines a wormhole is in front of them, I alluded to a paper published on light rays propagating through a wormhole: "Natural wormholes as gravitational lenses", John Cramer, Robert Forward, M. Morris, Matt Visser, G. Benford and G. Landis, Phys. Rev. D, vol. 51, #6, 15 March 1995, pp. 3117-3120.

And: "Observable effects from spacetime tunneling", P. F. Gonzalez-Diaz, LANL Abstract gr-qc/9708044, 19 Aug. 1997.

As yet we have no solid evidence for naturally occurring wormholes, so they shouldn't be counted in the universal mass problem until they are discovered. And I should further elaborate that matter flowing in one side of the throat makes that side appear to have negative energy density, while matter flowing out the other side makes it appear to have positive energy density. With matter flowing in and out through the throats, the thin-shell formalism shows an overall net gain of zero in either negative or positive mass contribution to universe. So there's a net mass balance overall.

It's my belief that wormholes will NOT solve the missing mass problem since they represent creatures contributing negative energy density. And recent astronomical data presented in conferences and published papers last month/this month have shown that there is not enough mass to close universe, it is ever-expanding. So it is an open universe.

Bye for now.

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Copyright (c) 1995 by Kim Burrafato and Jack Sarfatti. All rights reserved.