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Inertial Mass Separate From Gravitational Mass?
CPerdue writes with this excerpt from the MIT arXiv blog:
"The equivalence principle is one of the more fascinating ideas in modern science. It asserts that gravitational mass and inertial mass are identical. Einstein put it like this: the gravitational force we experience on Earth is identical to the force we would experience were we sitting in a spaceship accelerating at 1g. Newton might have said that the m in F=ma is the same as the ms in F=Gm1m2/r^2. ... All that changes today with the extraordinary work of Endre Kajari at the University of Ulm in Germany and a few buddies. They show how it is possible to create situations in the quantum world in which the effects of inertial and gravitational mass must be different. In fact, they show that these differences can be arbitrarily large."
General relativity is known to be incompatible with quantum mechanics. People are still trying to come up with a theory that reconciles the two.
This is similar to the way we knew:
* the constant speed of light (regardless of reference frame) was incompatible with the classical laws of momentum and energy [resolved by Special Relativity]
* the equations for low energy blackbody radiation and high energy blackbody radiation were incompatible with one another [resolved by quantum mechanics]
I haven't RTFA, but if they have something testable, I would think this means we have a basis for making quantitative measurements of what happens where GR and QM collide. (And hence a basis for coming up with a unifying theory.)
In a gravity well, this explains why we need so much fuel to get out. But that assumes that inertial mass acts like gravitional mass. If we change that, then suddenly we use HIGH inertial mass but low gravitational mass as rocket exhaust, tremendously reducing the mass of the rocket's fuel, which has exponential gains in increasing the potential payload.
excitingthingstodo.blogspot.com
... if you can lower the inertial mass of your spaceship can't you accelerate at ridiculous rates?
See E. E. Smith's _Lensman_ series for an exploration of that.
My own take: All bets are off since the principles are currently unknown. But assuming that things like energy conservation and action/reaction remain valid, an "inertial damper" seems likely to function as a way to transfer thrust evenly from the engines to the matter of the ship, crew, cargo, etc. (Or deliberately unevenly to achieve a convenient artificial gravity without spinning the ship.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
From Princeton's WordNet on the definition of "dampen":
# S: (v) dampen, damp, soften, weaken, break (lessen in force or effect) "soften a shock"; "break a fall"
A damper is either a movable iron plate to control the draft in a furnace, a device that decreases the amplitude of oscillations, or a depressing (as in emotional) restraint. Inertia is not a furnace, an oscillation, nor an emotion.
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"Professor" Aquino is widely known as a total nut. For Newton's sake, his theory "includes not only force particles and matter particles, not only general relativity and Quantum Gravity, but also a theory of consciousness"!! He can't publish his papers at the "Journal of New Energy"! Heck, one of his abstracts starts with "The existence of imaginary mass associated to the neutrino is already well-known" (and as a particle physicist, I've never seen any theory or experiment that even suggests an imaginary mass). He was worked at INPE (which is a very respected research institution) in a data-taking-monkey position; then got a job at the Maranhão state university (where there is NO research at all). He is listed at UEMA as having only a masters' degree (no PhD, so he can't have a research position). Please, don't mention him on an article about science. It's just like mentioning a 1940 VW Beetle when discussing today's F1 cars.