If an FTL spacecraft entered Earth orbit, how long would it take for humans to build a FTL spacecraft?

It's just another average day in the life of modern day earth. Suddenly a transmission from orbit washes over the planet! Oh no! An alien race, calling themselves the "Thull", has suddenly arrived in their spaceship and declares war on our race, threatening genocide! They are undoubtedly real, as anyone with a moderately powerful telescope can see their ship in orbit, and there was an obvious effect as their ship "slowed down" or "transferred from hyperspace" or method it used to travel.

Acting quickly and perhaps rashly, one of the governments of the world sends a nuke up. It has surprisingly good aim, and actually collides with the spaceship before detonating. To everyone's surprise it obliterates the Thull spaceship and every one on-board. This is probably because the most advanced war-fighting technology the Thull had were steak knives and tinfoil shielding. North Korea claims responsibility.

Assuming that:

1. By and large, it is accepted that the Thull were real
2. And that their spaceship was real,used FTL, and didn't sneak close to the planet
3. All physical traces of alien technology are now useless bits of scrap
4. Their method of ftl drive/travel doesn't use handwavium or unobtainium (it can be built by things the people on the planet have available). Recovery of the scrap shows no traces of anything unobtainable.
5. Humanity doesn't self-destruct TOO MUCH at the reveal of other intelligent life out there.

What's a realistic expectation for the collective of humanity for the length of time to determine the ftl method and build their own ftl ship/probe/test-bed?

Keep in mind, all they really have is the blatant demonstration that it's possible and some of the outward observable effects, they have to work out "˜how' on their own, with only the knowledge that its possible and within grasp (demonstrated by the general (lack of)advancement of the Thull).

Edit

Everyone, Thanks for the responses so far!

Most of what people are saying is that it's not possible to determine, and if that's the consensus then I can accept that, but I keep thinking back to an idea;

During World War 2, suddenly someone had a nuke and without question demonstrated it was possible to create that device. Where before places and nations only had theories, now they had proof, and within a relatively short period of time other places created their own nuclear devices. In-fact, most other places that had access to the brain power and materials figured it out.

Isn't this sort of example usually the case? It takes forever to make/invent the first one, but once people "know x is a thing," shortly everyone has it. Coming up with a working idea in the first place is hard for humans, but recreating it is "less hard". Or is this off base?

Edit2

Its seems the general consensus is "not enough information" which is fair. It leaves me a little freedom to work with the timeline, but for my use-case, ultimately what I'm hearing is I will have to decide on what timeline works best for the story, but probably a minimum time of a few years. If I could I would +1 everyone that contributed,but I feel Serban Tanasa provided the most useful answer because he elaborated out the different degrees of technological differences that could exist in a simple way.

posted about 8 years ago

Marky‭

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