Page 8 chapter 3rd paragraph down"The notion has gotten abroad since the advent of general relativity that inertia - the property of the massive objects that makes them resist acceleration by external forces - does not involve force."

Jim gives no reference in the literature back up this statement which to me seems totally bizarre red herring no one actually says anything like that.

He then goes on to make some obscure unintelligible remark about inertial forces.

In fact Einstein's general relativity says nothing at all about the origin of inertia where by the word "inertia" we mean resistance to external force.

That Einstein may have initially thought there was a connection is irrelevant because his final equations showed that there was no such connection after all.

Indeed, the role of the gravitational field is to provide force-free motions - the geodesics.

**measured locally with an accelerometer clamped to the test particle.**

**torsionless**Levi-Civita-Christoffel

**metric**connection which includes ALL inertial forces.

**Therefore, in Cartesian coordinates (inertial frame):**

**F^u is a real force (primarily electromagnetic)**

**All fictitious "inertial" pseudo-forces (centrifugal, Coriolis ....) are zero.**

**D^2r/ds^2 = d^2r/ds^2 + 2r(d@/ds)^2 + 2rsin^2@(d&/ds)^2**

**D^2@/ds^2 = d^2@/ds^2 - (2/r)(dr/ds)(d@/ds) + 2sin@cos@(d&/ds)^2**

**D^2&/ds^2 = d^2&/ds^2 - 2(1/r)(dr/ds)(d&/ds) - 2cot@(d@/ds)(d&/ds)**

**What is the meaning of these fictitious force terms that only appear in the spacelike components of the proper acceleration?**

**The local frame in spherical coordinates is not inertial. The unit radial vector er is always pointed at the test particle's retarded position (as shown by a light signal).**

**If the test particle has constant "inertia" m then Newton's 2nd law becomes Newton's first law when the real force F^u = 0**

**The geodesic equations are then**

**0 = d^2r/ds^2 + 2r(d@/ds)^2 + 2rsin^2@(d&/ds)^2**

**0 = d^2@/ds^2 - (2/r)(dr/ds)(d@/ds) + 2sin@cos@(d&/ds)^2**

**0 = d^2&/ds^2 - 2(1/r)(dr/ds)(d&/ds) - 2cot@(d@/ds)(d&/ds)**

**0 = d^2t/ds^2**

**Where the test particle geodesic orbit is r(t), @(t), &(t).**

**There is no Newton's third law here as yet. That requires additional physical assumptions.**

**In Newton's 2nd law F is the unbalanced net force on the test particle - no assumption about back-reaction on the source of F need be made yet.**

**What PURE general relativity does is to provide the global G^uvw fields for a given class of observers for the GEODESIC real force-free F = 0 test particle orbits.**

**inertia m of the test particles is nowhere to be seen at this classical level of pure gravity.**

**If we only had gravity all motions would be geodesics. However, we could not have stable sources Tuv with pure gravity.**

The inertia of test particles canceled out of the geodesic equation of motion. Therefore by elementary logic gravity cannot explain the origin of the inertia of test particles.

The only exception would be Wheeler's wormhole geons mass without mass etc., but that also needs non-gravity quantum physics.

Sent from my iPad speaking to Siri

Folks,

I wouldn't have spent my time writing the book if I didn't think that there is a reasonable chance we will eventually be able to build starships and stargates. And, truth be told, leaving the details of the enabling physics aside, it seems to me obvious that the only way to create a Jupiter mass of exotic matter in a structure with the dimensions of meters is to find a way to transform normal matter into the exotic matter needed in situ. As I say in the book, I do not claim that the ADM electron model is a substitute for the standard model of RQFT. But it sure has a lot of desirable features to recommend it -- like includng gravity without having to assume that gravity at short range miraculously becomes decades of orders of magnitude stronger than it is at all other scales. And I really like Asim Barut's lepton quantization scheme.

Best,

Jim

My Review of James F. Woodward’s book “Making Starships and Stargates” Springer 2013 V2

Jack Sarfatti

John G. Cramer, proponent of the transactional interpretation of orthodox quantum theory based on the Wheeler-Feynman back-from-the-future advanced potential of classical electromagnetism, endorses Woodward’s theory in the “Foreword”[i] I will play Devil’s Advocate usually assigned to Wolfgang Pauli. I pretty much agree with most of Woodward’s “Preface” except for his short shrift for the reality of flying saucers operated by an advanced intelligence. I mean, “advanced” in two senses including the back-from-the-future meaning. So I will home in on what I think are Woodward’s mistakes in his theory. I have nothing intelligent to say about his experiments except that scientists at Oak Ridge National Laboratory seemingly refuted them about fourteen years ago and that Woodward has not succeeded in getting a small model to fly under its own power in those fourteen years. Neither have any of his competitors in the fringe physics propellantless propulsion world.

Of course, we Pirates of Penzance are all on the same side against the establishment pundits of physics who, in Cramer’s words:

“Erect a ‘picket fence’ around those solutions of Einstein’s equations … to place stable traversable wormholes, faster-than-light warp drives, and time machines in the forbidden area outside the fence … it is presumed that nature does not allow such disreputable objects to exist.”

Woodward professes that “both inertial reaction forces and mass itself” have a “gravitational origin.” (p.xviii) He hedges on whether his approach will allow us to manufacture practical stargates (i.e., traversable wormholes without event horizons that do not pinch off killing the traveler and destroying any message in a signal) but is more optimistic that “at least a means of propellant-free propulsion can be created using Mach effects.”(p.xix) Using orthodox theory assuming Newton’s G requires an impossible Jupiter mass of exotic negative mass matter to make a stargate of few tens of meters across. Woodward invokes the classical 1960 ADM model. Curiously, I was a graduate student in physics at Brandeis in 1960 when Deser was there creating that model. Woodward does not seem to realize that he needs David Bohm’s hidden variable picture of classical particles piloted by a quantum information field in order for the ADM model to make sense. Niels Bohr’s “Copenhagen interpretation” with its magical collapse of the state does not even allow such a picture as ADM suggest. Since I am partial to Bohm’s picture, this is not a bad thing. Woodward alleges that the ADM model “when fixed” shows that there is a lot of negative energy matter locked inside ordinary matter like the electron. Of course, we now know since 1998 that about 68% of our observable universe’s stuff is exotic “dark energy” exactly what we need. However, its energy density 6.7 x 10

^{-10}Joules/meter^{3}is way too small for our purpose unless we can amplify it by many powers of ten. Perhaps, the advanced intelligences in the flying saucers are doing just that? Woodward claims that the negative exotic matter creating universally repelling antigravity is screened at a distance by distant matter by. This is definitely not mainstream textbook physics taught in the top universities. He proposes a kind of catalytic avalanche effect, like the straw that broke the camel’s back, or the butterfly wing flapping creating a super storm across the world, a pistol shot causing an avalanche. [ii] What is disturbing, however, is Woodward’s Frankenstein Monster supposing he were on the right track, fortunately my bet is that he is not, but I could be wrong. Woodward intends to expose a Jupiter mass of exotic matter as his end product, and to concentrate it in a region a few meters across. If this isn’t madness I don’t what is. ;-)

[i]“Woodward extended the work of Sciama in investigating the origins of inertia in the framework of general relativity by consideration of time-dependent effects that occur when energy is in flow while an object is being accelerated. … It predicts large time-dependent variations in inertia, the tendency of matter to resist acceleration. … The inertial transient effects … have G in the denominator, and dividing by a small number produces a large effect. … he has been able to demonstrate tens of micronewton-level thrusts … they represent convincing evidence that Woodward-Sciama inertial transients are a real physical phenomenon and that the underlying calculations behind them should be taken seriously … Personal flying cars and reactionless heavy-lift Earth-to-orbit space vehicles cannot be ruled out … The … inertial transient … second term, which is always negative and can in principle drive the inertial mass to zero or negative values … could … be used to provide the ‘exotic mass’ needed to stabilize wormholes and produce superluminal warp drives. ” P.ix

[ii] “Exotic matter is available in everyday matter, normally screened by the gravitational interaction with chiefly distant matter in the universe. … exposure can be achieved by cancelling the gravitational effect of the chiefly distant matter with nearby exotic, negative rest mass matter. The amount … needed to trigger this is miniscule in comparison with the Jupiter mass that results from exposure. Mach effects … produce the exotic matter required … for exposure.” P.xix