The US military is considering testing the principle behind a type of
space drive which holds the promise of reaching Mars in just three
hours.

The problem is, it’s entirely theoretical and many physicists admit they don’t understand the science behind it.

Nonetheless, the so-called "hyperdrive" concept won last year’s
American Institute of Aeronautics & Astronautics award for the best
nuclear and future flight paper. Among its defenders is aerospace
engineer Pavlos Mikellides, from the Arizona State University in Tempe.
Mikellides, who reviewed the winning paper, said: "Even though such
features have been explored before, this particular approach is quite
unique."

The basic concept is this: according to the paper’s authors – Jochem
Häuser, a physicist and professor of computer science at the University
of Applied Sciences in Salzgitter and Walter Dröscher, a retired
Austrian patent officer – if you put a huge rotating ring above a
superconducting coil and pump enough current through the coil, the
resulting large magnetic field will "reduce the gravitational pull on
the ring to the point where it floats free".

The origins of this "repulsive anti-gravity force" and the
hyperdrive it might power lie in the work of German scientist Burkhard
Heim, who – as part of his attempts to reconcile quantum mechanics and
Einstein’s general theory of relativity – formulated a theoretical
six-dimensioned universe by bolting on two new sub-dimensions to
Einstein’s generally-accepted four (three space, one time).

As New Scientist explains, Heim’s two extra dimensions
allowed him to couple together gravity and electromagnetism, and
permits conversion of electromagnetic energy into gravitational and
vice-versa – something not possible according to Einstein’s four
dimensions, because "you cannot change the strength of gravity simply
by cranking up the electromagnetic field".

Heim, then, proposed that "a rotating magnetic field could reduce
the influence of gravity on a spacecraft enough for it to take off" –
an idea which caught the eye of Wernher von Braun when it was first
proposed in 1959 and the rocket scientist was working on the US’s
Saturn launch vehicle.

After the initial excitement died down, however, Heim moved on to
other projects and his hyperdrive theory slowly gathered dust until the
arrival of Walter Dröscher in 1980. Dröscher expanded on Heim’s work,
in the process reactivating two further dimensions the latter had
originally discarded. Thus "Heim-Dröscher space" was born – an
eight-dimensional concept of which Dröscher says: "If Heim’s picture is
to make sense, we are forced to postulate two more fundamental forces."

The said extra forces are: "A repulsive anti-gravity similar to the
dark energy that appears to be causing the universe’s expansion to
accelerate"; and a second resulting from the "interaction of Heim’s
fifth and sixth dimensions and the extra dimensions that Dröscher
introduced". Crucially, it "produces pairs of ‘gravitophotons’ –
particles that mediate the interconversion of electromagnetic and
gravitational energy".

The groundwork done, Dröscher then teamed up with Häuser to produce
the award-winning "Guidelines For a Space Propulsion Device Based on
Heim’s Quantum Theory."

So far so good – in theory. However, as NS notes: "The majority of
physicists have never heard of Heim theory, and most said they couldn’t make sense of Dröscher and Häuser’s description of the theory behind their proposed experiment."

Furthermore, Dröscher and Häuser’s proposed practical experiment to
prove their theory requires "a magnetic coil several metres in diameter
capable of sustaining an enormous current density" – something which
the majority of engineers say is "not feasible with existing materials
and technology".*

So, Mars in three hours? As NS puts it: "Dröscher is hazy about the
details", but "suggests that a spacecraft fitted with a coil and ring
could be propelled into a multidimensional hyperspace" where "the
constants of nature could be different, and even the speed of light
could be several times faster than we experience". Then, he says, a
quick three-hour jaunt to Mars would indeed be on the cards.

More here.