Physics@FOM 2015 - Masterclass Alan Guth 

Instablaster.

You are wrong here. This has to do with years of practice. You would be as good as those scientists if you had all those years of practicing the science. You are as intelligent as anyone else.

Nice answer !!

I love how he is patient with all questions and is nice to go into further explanations. A top professor.

LOL!

I think you need to shut up.

You should check you own pronUnciation!!!

Yes, in many many fields. But the crazy thing is some fields have positive energy and some fields have negative energy, and the amount of both in the visible universe may actually be zero (its definitely very close to zero).

Observable universe may be a clearer term than visible universe.

Martin Zitter That's practically tautologous IMHO - the speed of light is the same for all electromagnetic waves, the only thing which makes the visible universe any smaller in a practical sense is red-shift.

Tim Blizzard ~ We recently began observing the universe via gravitational waves. They are neither visible or electromagnetic in nature.

Martin Zitter But they travel at the speed of light. You cant argue with Einstein.

Santhikrishnan S Everywhere or to reuse a term of Minkowski's: Everywhen. The only difference is the type of expansion has become non-inflationary in our patch of space. We do not know how big this patch is, except for a lower bound. It is likely inflation only ended for our patch and other disconnected patches but continues everywhere else.

Thank you for replying.But What does 'our patch of time mean'? and where is this 'everywhere else'?

+Santhikrishnan S "Our patch of time" doesn't mean much I don't think. By our patch of space (or space-time but the important concept here is expanding space) I think Guth is referring to the region of space, that contains us, where inflation stopped so that this region space is no longer being driven apart at a rapid rate. So our patch would be bigger than but include our observable universe. There are 2 important consequences to consider: 1. Inflation would likely stop in several patches of space, not just the one we are in. 2. the space between the patches is still inflating (growing ~exponentially) so that these patches would be separated at a great rate. So if we call our patch of space our universe then we could call the other patches other universes. None of this will ever be observable it seems. All we can do is try to find out if inflation is true in the region of space-time we can observe. If inflation did happen then we will have to take its consequence of creating many universes seriously.

Sir/Madam, Thank you for your valuable information.

But that would mean all the galaxies are flying away from a central point around which the universe is spinning, and since that we see all the galaxies moving away from us at the same rate in all directions, that would mean the entire visible universe, with hundreds of billions of galaxies, is spinning around us for some reason. How would we explain that? Also I think we would see space distortion over large distances, which we don't. The "big bang" is a very consistent theory, and anyway we can actually see the afterglow of that period in the cosmic microwave background. We literally know that the universe was once dense and hot, and that it expanded.

Because it didnt.

seog servant Please, get out and don't troll if you don't have anything of value to say. This video is about inflation, and has nothing to do with ancient myths or imaginary figures. Guth nor hardly any reputable scientist believes in the primitive, useless concept of something called "god." Human intelligence and knowledge has advanced and matured to the point that most intelligent and educated people have abandoned the absurd, ancient, unfounded, supernatural ideas of our ancestors.

AG You have no clues on what values are. Unfortunately this great country consist of a lot of uneducated people like you who have the ignorance robe on and are blind to all these signs of design in our Universe.

seog servant How the fuck would you know if I have no clue what values are? How the fuck do you know how educated I am? Blind to what signs of design? There aren't any signs of design at all. That's why most scientists and many others reject design and see how absurd it is - but yet they're uneducated and the primitive myth-believing hordes are more enlightened? OK...if it makes you feel better.

Mandingo Blax If this is your final say, I must say you need some brain.

Mandingo Blax My problems are dumb people like you. Why you choose to have no life, and somebody else does the thinking for you? I am fighting to eliminate ignorance among stupid people.