By definition, a tachyon would have to travel faster than light. But the problem with that is the very simple fact that it would violate the maximum speed in space-time and be instantly destroyed according to the laws of physics.

Likewise, it would be pretty hard to catch a particle comparable to an atom in space. Your best shot would be to put out a collection shield, have the particle collide with it and stop its motion with the overwhelming mass of your spacecraft.

No it’s not. But when you exceed neutron star density, you get a complete collapse of the object since it’s being held together by degenerate pressure. And that collapse is what we know as a black hole. The word “similar” referred to the energy density of the warp drive requirements, not of a neutron star. Sorry if this wasn’t clear at first.

“A Jupiter-mass black hole would be 6m across…”

Well, 5.6 m actually. But then again, we’re not calculating a Jupiter mass black hole. Instead, we’re looking at the mass represented by 10^45 J in a cubic meter, so the resulting equation will look like this:

r_s = 2G(1.11 × 10²⁸) / c² = 16.4784 m

Where G is 6.673 × 10^-11, so if we multiply the Schwatzschild radius by two, we get a diameter of 32.9568 m which we can pretty safely round up to 33 meters.

“…and [the authors] talked about putting that mass into a 10m cube, which is fine.”

The paper makes no mention of making a black hole and putting it into a 10 meter cube. If you note how they came up with the energy requirements for the warp drive, they used a spacecraft with a volume of 1,000 cubic meters and multiplied that by the energy density needed to increase the Λ value in the following manner on page 11…

V_craft = 10 m × 10 m × 10 m = 1000 m³
E_c = Λ_c × V_craft = 10⁴⁵ J

Also how is it fine to create a black hole and stuff it in a cube? And wouldn’t it make sense that warp drive makers trying to create an extremely high energy density in a small area of space might just create a black hole?

“You should have questioned your own belief that a published journal article would contain a mistake that obvious.”

Err… the post assumes that Obousy and Cleaver were correct which is why it uses the numbers and figures they provided without question. I said absolutely nothing about the paper containing any mistakes. They found the energy requirements. I tried to use their results to figure out who could meet them.

“Retract this blog post and start over.”

Sure. Any other posts that you’d like me to remove or edit to your standards? After all, it’s not like it’s my blog or anything… < /sarcasm>

The last paragraph, though, shows major errors of the underlying science, which is a very different matter than failure to share the sort of implicit technological assumptions that are being talked about.

Neutron star density is not black hole density. Period. Black hole density (not just volume) depends on the mass, and a black hole the size of the Sun would be 3 km across. A Jupiter-mass black hole would be 6m across, and Obousy and Cleaver talked about putting that mass into a 10m cube, which is fine. (And that’s a thousand cubic meters, not a cubic kilometer!)

That’s the sort of thing that Obousy and Cleaver would have noticed immediately, and the referees would have seen it if they didn’t. You should have questioned your own belief that a published journal article would contain a mistake that obvious. As it is, I’m afraid this article is very much the analogue of chiding Goddard for believing that rockets can operate in space without something to push against. The gross errors of math and science are yours, not Obousy’s and Cleaver’s.

Retract this blog post and start over.