[latebind (OP)]

Which of these discoveries would have the biggest impact on the world , science and life?

1)Discovery of basic life elsewhere in the milky way.
2)Contact by intelligent lifeforms(friendly).
3)Time travel.
4)Faster than light speed (IE: wormholes)

[graham.d]

I think (3) time travel. The paradoxes that result would be immense, which is why it is probably not possible (except forward in time of course, which is easy in principle).

Then (2)Contact by intelligent lifeforms(friendly). This gives us (1) anyway and could potentially give us (4).

Then (4) as this opens up the universe to exploration so we could find out about (1) quickly.

Then (1)

Of course any would be remarkable right now.

[lightarrow]

Which of these discoveries would have the biggest impact on the world , science and life?

1)Discovery of basic life elsewhere in the milky way.
2)Contact by intelligent lifeforms(friendly).
3)Time travel.
4)Faster than light speed (IE: wormholes)

[ironic mode on]The first one, since it would be the first time that ANY form of intelligence would be discovered in the universe [][ironic mode off]

I think time travel, even in the case in which there would be no paradoxes (example: we meet in the past a line of universe which from that moment goes in another direction, so we would find another ourself, the one who travelled the first line).

The other discoveries could be important but could also be non important at all: the discovery of basic life or even contact with friendly intelligent lifeforms woudn't mean they would tell us something about their technology or that we would have the possibility to make very new things; faster than light speed: it depends on how much faster []

[LeeE]

Given the probability that intelligent life exists elsewhere in the universe, then FTL travel will lead to contact with [other] intelligent [it's debatable whether rationality is a part of intelligence, and by that standard, whether we qualify] life forms.  In turn, intelligent life depends upon there being basic life, so the order of three of the choices are interlinked: 4, 2, 1.

I don't think that Time travel (as in going back in time, for everyone goes forward in time anyway) is ever going to happen, at least not without a parallel-universe solution, because of the causality issues.