Answer: Will we be able to live in another galaxy?

David Gross, Nobel Laureate in Physics 2004, has answered a selection of your video and text questions from YouTube and Facebook, including his explanation of how we detect neutrinos, his thoughts about the LHC and information about what books influenced his career choices.
Thanks to everyone for your participation.

[DinoAgent]

"Only" 10 billion galaxies in the visible universe???
I've always heard hundreds of billions.

[damienboyle]

I'm confused. If time slows down around anything that travels at the speed of light, doesn't that mean any persons travelling at light speed experience a shorter journey. Am I wrong in thinking that if someone travelled to the nearest star at light speed we would have seen them gone for 5 years, but for the traveller it would have felt merely seconds.

[Territomauvais]

@Theophagous The distance between stars and galaxies though is SO dramatically different.

4 light years to the nearest Star could be negligible to our descendants, but 2 and a half MILLION light years to the Andromeda Galaxy? That can't be a negligible amount of time if the species is awake at all, lol.

[Territomauvais]

It's a sad reality I've always accepted....we'll be able to colonize our own Galaxy but the Universe is [probably] just too big for one sentient species.

[Ideophagous]

@Territomauvais Considering that we may be able to expand our lives very long, or even become practically immortal perhaps, with genetic manipulations and such, the time it would take to travel between galaxies may become very negligible to us (or rather to our descendants).. not to mention that we are probably barely scratching the surface of what there's to know, so there may be some kind of shortcut that we have yet to discover..

[Agamemnus]

The universe that we can currently see and detect only reveals "10 billion". The OBSERVABLE universe is everything that could theoretically be observed if our technology allowed it, must consist of hundreds of billions of galaxies. Some simulations say up to 500 billion. Then there is the unobservable universe, which may or may not contain more.

[einherz]

we are living in other galaxy right now, befor we was just atoms of hidrogenium carbon nitrogen etc and lives in our own galaxy, but befor we does, we lived out of galaxy and was clean energy now we calling this energy god, nature and primary condition of universe, so actualy we are live in all universe in same time, question is will another galaxy be able to back to us, relate space-time is same, but if we will got again speed close to c, so better talking about space-time come through us, not we through it, as relict things have no speed and constant relate all other things what hapens before, now, and will after