Just...................whatever [3]

That's Dark Flow, meaning the theoretical drift of the Universe that's not accounted for by Hubble's Law Big Bang expansion, right?   I think it's still something that people are trying to measure but there's not general agreement. It would be cool if it were definitively measured because it could  give a some clues about what might be outside our visible horizon.

I'm even more excited about the recent claims to have measured Gravity Waves.  That will take a year or two of peer review before it's really meaningful, but the implications are so huge it's hard to even say what they might imply.

Halfwise knows I'm a big fan of Luminiferous Aether Drift (Michelson /Morley got it wrong IMHO  ) The methodologies and hypotheses of a century ago were naive and ignored all sorts of potential currents and counterflows in the cosmos for the sake of a simple model. These new areas of research may finally begin to set the record straight.  

wow thats wow! no one has ever found out what gravity actually looks like before, am I right? they dont know what it actually is?.   

That's exactly right.  

Just a note of caution, I never spotted anything wrong as such in that vid, but it might just be some of it is out of date- for example they say about the early computer like device ( Antikythera mechanism) that scientist are 'mystified as to how it works'.
Except they do know how it works now and there are have been variety of replicas of it made.
Its an amazing little device, a clockwork counting mechanism.

So...this may sound kinda stupid, but has anyone else realized just how big the universe is supposed to be? Mind boggling...

http://scienceblogs.com/startswithabang/2013/01/05/how-many-planets-are-in-the-universe/

http://scienceblogs.com/startswithabang/2012/09/28/the-deepest-view-of-the-universe-ever/

Go on, then – how long to get across the whole universe?
Well, we can only measure the universe as far as we can see it. With the best telescopes we have, that’s about 15 billion light years (or 90 billion trillion miles – I won’t even bother trying to write that out with zeros) in every direction. So at the speed of light, it’d take at least 30 billion years to cross it. That’s about 2 billion years longer than the age of the universe itself.

Ah. So it’s big, then?
Like I said: crazy big. And that’s just the bit we can see. Beyond that, we know it extends even further, because the light from the stuff we can see at the ‘edge’ has taken 14 billion years to reach us, and the universe has expanded quite a bit since then! It might even curve back on itself, like sea does as you sail around the globe. If that were the case, you could circle the universe and end up back where you started from.

    

malickfan wrote:

Go on, then – how long to get across the whole universe?
Well, we can only measure the universe as far as we can see it. With the best telescopes we have, that’s about 15 billion light years (or 90 billion trillion miles – I won’t even bother trying to write that out with zeros) in every direction. So at the speed of light, it’d take at least 30 billion years to cross it. That’s about 2 billion years longer than the age of the universe itself.

Ah. So it’s big, then?

I'm afraid it's a bit bigger than that. Think about it this way: If an object were to start traveling straight for us from the visible edge at this instant, it would take at least 15 billion years to get here, so as it passes us, the "far edge" will now be more than 30 billion light years away. 30 billion years later, when the object finally gets to where the "edge" was when it passed us, the edge will now be another 30 billion light years ahead of it. It can never catch the "edge" according to our current accepted physics.

It's THAT big.

This puts it all in perspective visually.

David H wrote:

malickfan wrote:

Go on, then – how long to get across the whole universe?
Well, we can only measure the universe as far as we can see it. With the best telescopes we have, that’s about 15 billion light years (or 90 billion trillion miles – I won’t even bother trying to write that out with zeros) in every direction. So at the speed of light, it’d take at least 30 billion years to cross it. That’s about 2 billion years longer than the age of the universe itself.

Ah. So it’s big, then?

I'm afraid it's a bit bigger than that.  Think about it this way: If an object were to start traveling straight for us from the visible edge at this instant, it would take at least 15 billion years to get here, so as it passes us, the "far edge" will now be more than 30 billion light years away.   30 billion years later, when the object finally gets to where the "edge" was when it passed us, the edge will now be another 30 billion light years ahead of it.  It can never catch the "edge" according to our current accepted physics.

It's THAT big.

So essentially, even if the universe isn't infinite, it's still so big we'd never be able to find out either way.

As I said CRAZY big, maths is not my strong point but that's just plain...scary...

@Chris

chris63 wrote:

Why is he watching him?...

God likes to watch?

Thinking about another son   

Pettytyrant101 wrote:Just a note of caution, I never spotted anything wrong as such in that vid, but it might just be some of it is out of date- for example they say about the early computer like device ( Antikythera mechanism) that scientist are 'mystified as to how it works'.
Except they do know how it works now and there are have been variety of replicas of it made.
Its an amazing little device, a clockwork counting mechanism.

yes but they dont know who made it or for exactly what purpose. it may count stars and stuff but why they dont know. ie is it for navigation for the sea or for land, this is the mystery.

David H wrote:

malickfan wrote:

Go on, then – how long to get across the whole universe?
Well, we can only measure the universe as far as we can see it. With the best telescopes we have, that’s about 15 billion light years (or 90 billion trillion miles – I won’t even bother trying to write that out with zeros) in every direction. So at the speed of light, it’d take at least 30 billion years to cross it. That’s about 2 billion years longer than the age of the universe itself.

Ah. So it’s big, then?

I'm afraid it's a bit bigger than that.  Think about it this way: If an object were to start traveling straight for us from the visible edge at this instant, it would take at least 15 billion years to get here, so as it passes us, the "far edge" will now be more than 30 billion light years away.   30 billion years later, when the object finally gets to where the "edge" was when it passed us, the edge will now be another 30 billion light years ahead of it.  It can never catch the "edge" according to our current accepted physics.

It's THAT big.

I dont understand   do you mean the universe has doubled in size while the object was travelling? help me no understandy.

wow there must be billions of other Earth like planets and billions of all manner of creatures, it BOGGLES the mind. Just think, at this precise moment Jar Jar Binks is somewhere out there annoying the crap out of poor defenceless aliens

Mrs Figg wrote:

David H wrote:

I'm afraid it's a bit bigger than that.  Think about it this way: If an object were to start traveling straight for us from the visible edge at this instant, it would take at least 15 billion years to get here, so as it passes us, the "far edge" will now be more than 30 billion light years away.   30 billion years later, when the object finally gets to where the "edge" was when it passed us, the edge will now be another 30 billion light years ahead of it.  It can never catch the "edge" according to our current accepted physics.

It's THAT big.

I dont understand   do you mean the universe has doubled in size while the object was travelling? help me no understandy.

I'll give it a try, but understand that these things are best understood with the artistic and poetic parts of your mind. It's like a simple, beautiful song with a couple easy harmony parts, and if I try to hum it for you and the beauty doesn't come across, it's neither your fault nor mine.

OK, with that out of the way, here's the basic melody.

Close your eyes and imagine you're walking on a calm, foggy night with your collar turned up, and it's the most normal thing in the world. You're enjoying the walk, and you're not in any hurry to get anywhere. About 150 yards ahead of you, you can just barely make out the glow of the next streetlight, and when you look behind you, you can just make out another one at the same distance . A funny thought passes across your mind, "At this exact moment, my World is no bigger than what lies between those two lampposts. Everything else is a fantasy."

Now imagine that as you're musing on this curious thought, a shadow passes in front of the light ahead, and you realize there's another pedestrian out enjoying the foggy evening. "I wonder what his World looks like?" you ponder. "Our worlds include each other, but there are things in my World that are too far behind me for him to see, and maybe there are things behind him in his world that are too far for me to see..."

As you both walk towards each other, you slowly come into clear focus for each other. You wish each other a good evening as you pass, your Worlds are identical for one brief instant, and then you each walk off into the fog and out of each others Worlds.

OK, that's all there is to the basic melody. Try not to attempt to apply it to any concept bigger than a foggy evening until you feel completely comfortable with it. Let it sink in, and if you're still interested tomorrow I'll try to add a little more to the tune.

Nice and poetic.   

Mrs Figg wrote:wow there must be billions of other Earth like planets and billions of all manner of creatures, it BOGGLES the mind. Just think, at this precise moment Jar Jar Binks is somewhere out there annoying the crap out of poor defenceless aliens

No, natural selection would have dealt with that.

Eldorion wrote:This puts it all in perspective visually.

This is why I sometimes wonder if it's all just a big joke and I'm walking around believing the people around me are real. I try not to think about the vastness of the universe, it's depressing to me

Close your eyes and imagine you're walking on a calm, foggy night with your collar turned up, and it's the most normal thing in the world.- David

Yes, but am I drunk? - I feel this may be important information for later, especially if quantum becomes involved.   

Petty, your'e as pissed as a fart & Im as sober as a judge, who's the most drunk ??   
And Dave, that was such a lovely way of getting over something as mind blowing as the enormity of "space"   Flowed gently like a meandering stream. If only my archaic teachers at school put across subjects as you have, I might have learnt more & stopped truanting !

Speaking of meandering....

http://theweek.com/article/index/260417/speedreads-bear-gets-head-stuck-in-jar-walks-down-street-in-canada

Im glad that Bear is ok !   Did look funny with that thing on its head !

Pettytyrant101 wrote:Close your eyes and imagine you're walking on a calm, foggy night with your collar turned up, and it's the most normal thing in the world.- David

Yes, but am I drunk?

That depends. Can you touch your nose with your index finger?

That's the beauty of this exercise. It's both an illustration of a basic astrophysical principle and a sobriety test at the same time!