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https://futurism.com/the-byte/elon-musk-...ed-rockets

EXCERPTS: . . . if a new tweet means anything, SpaceX CEO Elon Musk already has his eyes set on a much higher-tech rocket fuel: antimatter. [...] Physicists have never succeeded in producing very much, but if they could, many believe it could be an incredibly potent fuel. In 2006, for instance, NASA estimated that just a few milligrams of antimatter could push a spacecraft all the way to Mars. And more recently, some physicists have speculated that antimatter propulsion could be practical within ten years. But as to whether SpaceX is secretly working on antimatter propulsion? We’ll probably just have to wait to find out... (MORE - details)

(Mar 9, 2021 08:37 AM)C C Wrote: [ -> ]EXCERPTS: . . .  if a new tweet means anything, SpaceX CEO Elon Musk already has his eyes set on a much higher-tech rocket fuel: antimatter.

That's an awful lot of meaning being extracted from a single word of a two-word post. (Elon's tweets are like semantic antimatter!)

A twitter page writes, "Term of the day: antimatter rocket"

And Elon replies, "Ultimately, yes"

(OMG!!! HE SAID YES!!! Let's all go berserk!)

Quote:Physicists have never succeeded in producing very much, but if they could, many believe it could be an incredibly potent fuel. In 2006, for instance, NASA estimated that just a few milligrams of antimatter could push a spacecraft all the way to Mars. And more recently, some physicists have speculated that antimatter propulsion could be practical within ten years.

Well, antimatter does possess the highest theoretical energy density. Hence it would be the most efficient way to store energy in terms of energy/kg of fuel. How much of that energy would be usable energy might be a different question. But it's certainly out there as kind of a holy grail of future rocket science.

A relatively small tank of antimatter (how would you contain it?) could theoretically serve as fuel for light-speed interstellar starships at some point. Accelerate halfway to a destination star, attain 99+% of the speed of light relative to Earth, then decelerate for the second half of the journey. Time dilation might even make it practical for the ship's occupants. (Who could never return to the Earth they left. The journey would be time as well as space travel.)

Quote:But as to whether SpaceX is secretly working on antimatter propulsion? We’ll probably just have to wait to find out...

I expect that the "yes" in Elon's two-word answer was just him acknowledging the theoretical potential that antimatter holds as the ultimate rocket fuel. He's just acknowledging that the possibility is out there.

But pay careful attention to the word "ultimately". In relativistic Elon Time, if one of his organizations is working on something, Elon expects it to be completed in a reasonable amount of time, from few months to a few years. In the Earth reference frame that we call "real life", it might take considerably longer than Elon estimates it will take.

You have to factor in time dilation in Elon's Reality Distortion Field.

So when Elon uses the word "ultimately", he means indefinitely in the future, as kind of the ultimate theoretical destination of engineering progress. So "ultimately" in Elon-time could mean 'centuries to never' in our much more mundane reference frame.

So I read his use of the word "ultimately" as telling us that they are not working on anti-matter propulsion. At least not yet.

Is the reality distortion field a thing?