----- Original Message -----

From: Chandiran Homer

To: [address removed]

Sent: Tuesday, January 31,[masked]:25 AM

Subject: RE: [Physics-61] Scientists hope to understand the Big Bang and the very early universe

Here is something to you all who have been in this dialogue on the Big Bang.  The Video is almost 2 hr long. the second link relates to the news on the theory of " conformal cyclic cosmology" 

Sir Roger Penrose, Aeons before the Big Bang (Copernicus Center Lecture 2010)

http://www.youtube.com/watch?v=4YYWUIxGdl4&feature=related 

News (Nov 2010 BBC) on Cyclic Universe as discussed in Aeons before Big bang 

http://www.bbc.co.uk/news/science-environment-11837869 

and on the Concept of "Nothing" do we really have an understanding of the concept of "That which is not every thing" or is nothing a theory that has experimental proof of similar to Big Bang theory or any other scientific theory. But that would be another dialogue altogether. 

Chandiran M.Homer-Vanniasinkam
What is unattainable speaks not of what can be pursued

---

From: [address removed]
Subject: Re: [Physics-61] Scientists hope to understand the Big Bang and the very early universe
To: [address removed]
Date: Mon, 30 Jan[masked]:31:29 -0500

Yes, Dave, you're right. There may well be something over the edge. But we'd never be able to see it. Due to the large distance, more space is being created per unit time (whatever the unit is) than light can traverse in that time.

 

In some respects, it's as if we were driving from Toronto to Waterloo at 100 km/hr, but those mini earthquakes I mentioned were adding roadway at a rate of 110 km/hr. You'd never get there!

 

===================

 

On the original matter of "what's outside the universe", here's a quote from a short Scientific American article, a mini-profile of Fontini Markopoulou Kalamara of the Perimeter Institute.

 

"Markopoulou Kalamara approached LQG's extraneous space problem by asking, Why not start with Penrose's spin networks (which are not embedded in any preexisting space), mix in some of the results of LQG, and see what comes out? The result was networks that do not live in space and are not made of matter. Rather their very architecture gives rise to space and matter."

 

For the full (short) article, see http://www.scientificamerican.com/article.cfm?id=throwing-einstein-for-a-l

----- Original Message -----

From: Dave Noel

To: [address removed]

Sent: Tuesday, January 24,[masked]:32 PM

Subject: Re: [Physics-61] Scientists hope to understand the Big Bang and the very early universe

So, does that mean the age of the "visible" universe is 13.9 billion years, and there's a possibility of a bunch of stuff over the edge of the 'waterfall' of light speed that we will never know about? And if that's the case, is it stupid to conceive the universe could be infinite in size, and by extension, age?

I understand that the big bang theory is fairly well established, but this expanding model seems like our Universe's horizon could be just an illusion if the edge represents a light speed observational barrier. Am I missing something?

Dave Noel

On[masked], at 2:08 PM, Larry Smith <[address removed]> wrote:

Oh boy, here comes another of my long emails. Let's see how short I can make it. (I'm not good at this.)

First of all, nothing can travel faster than the speed of light. Right? Well, not quite.

The Hubble constant is roughly 70 km/sec per megaparsec. (For those who aren't familiar with the term, a parsec is about 3.26 light years).

So if a galaxy is a megaparsec (which I'll write as MP) away, it's receding from us at 70 km/sec.

Something 2 MPs away is receding at 140 km/sec.

Something 10 MPs away is receding at 700 km/sec.

The speed of light is about 300,000 km/sec. Dividing that by 70 km/sec gives us just under 4286.

So a galaxy 4285 MPs away would be receding at 70 times 4285 =[masked] km/sec.

What about a galaxy 4286 MPs away? 70 times 4286 is[masked] km/sec, which is faster than the speed of light.

Huh?

The resolution of this paradox involves a clearer definition of velocity.

Let me get something out of the way first. Yes, individual stars are moving (e.g. orbiting around the center of their galaxy). And galaxies are moving (the Andromeda galaxy and the Milky Way galaxy are approaching each other, and will collide in 3-5 billion years). But these will turn out to be fairly minor corrections to what I'm about to talk about, so I'm going to ignore them.

So I'm going to make the statement that, other than what I mentioned in the previous paragraph, all the galaxies in the universe are standing still!!!

OK, at this point you want me to make up my mind. Are the galaxies receding from each other, or are they standing still?

And the answer (you're not going to like this) is *both*.

Huh???

Let's go back to what we've talked about earlier, the creation of new corpuscles of space. But let's start with a more earth-bound analogy.

Imagine that the 401 is a straight line from, say, Toronto to Waterloo., roughly 100 km. And once a week, a minor earthquake (or whatever) causes lava to spew up somewhere on the 401, pushing the asphalt aside making a mound, and adding another kilometer to the road. So after 1 week, based on the odometer readings when you drive between them, the cities are 101 km apart. After 2 weeks, they're 102 km apart. And so on.

Are the cities moving? No. But according to the odometer, they're receding from each other at the rate of 1 km/week.

The expansion of the universe is like that. Corpuscles of space seem to be popping into existence (at a rate captured by the Hubble constant of 70 km/sec per MP), increasing the distance between galaxies. And if you get far enough apart (4286 or more MP away), the remote galaxies appear to be receding faster than the speed of light. But it's not that they're moving so much as extra space is being created, confusing matters.

So it's this updated concept of velocity that allows the universe to expand at seemingly faster than the speed of light and gives the radius of the universe as 46-47 (based on the uncertainty of the exact value of Hubble's constant) billion light years.

By the way, if you multiply 3286 MP times 3.26 (to convert megaparsecs to megalightyears), you get 13,972,360,000 or 13.9 billion light years, which, when divided by the speed of light, gives you 13.9 billion years, the age of the universe. (It's a bit high because the Hubble constant is a bit higher than our 70 km/sec/MP value.)

On 1/24/2012 1:11 PM, Wayne McCracken wrote:

Actually I was wondering if someone (e.g. you) would comment on that.  I've read that before but haven't explored the reasoning.  I will this time.  I decided to ignore this in my description as I wanted to simplify things.  

And I knew it is "Inflaton".  My comment was just so that people wouldn't think that it was just misspelled.

Wayne

On Tue, Jan 24, 2012 at 12:57 PM, Larry Smith <[address removed]> wrote:

Good comments, as usual, Wayne. But you made one (quite common) mistake.

The *age* of the universe is 13.7 billion years. But due to the expansion of the universe, the distance to the edge of the observable universe (i.e. its radius) is about 46-47 billion light years away. See, for example, http://en.wikipedia.org/wiki/Observable_universe

BTW, the Inflaton field is correctly named. See, for example, http://en.wikipedia.org/wiki/Inflaton, where the final sentence reads <The process is "inflation"; the particle is the "inflaton".>

On 1/24/[masked]:39 PM, Wayne McCracken wrote:

My "simplified" cut at it . . .

The physics that we experience in our universe (i.e. matter/energy/forces, dimensions & time) is a result of the physics that was created at the Big Bang (BB) 13.7 billion years ago.  At that time a sphere centred on the point of origin of the BB started expanding at the fastest possible speed (i.e. the speed of light).  Obviously the radius of this sphere is currently 13.7 billion light-years.  Nothing that originated in the big bang can ever be outside this expanding sphere because it would have had to travel faster than the speed of light to get there.

Since our physics originated at the BB and doesn't exist outside this sphere, there is no such thing as our physics (i.e. matter/energy/forces, dimensions & time) outside the sphere.  This expanding sphere IS the Universe as we know it.  Outside our universe literally nothing exists.  No space (this would require dimensions for a co-ordinate system to measure space), no time and no forces.  No physics.  NOTHING!!!

I think that the major obstacle to understanding "what is outside our universe" is simply the inability of our minds to comprehend what nothing is.  I think that nothing in this case means a lack of existence!!!  Outside our universe nothing exists.  Not easy to get your head around !!!  You just need to accept it.  Something like a lot of quantum mechanics.  

===================

And then there is the Inflationary multi-universe theory. . .  

At least one version of which holds that there was an Inflaton field (should be called an Inflation field I think) that was expanding at a super stupendous rate.  A random fluctuation (quantum fluctuation ??) in this field allowed our physics to drop out of the Inflaton field as a non-inflating bubble immersed in the Inflaton field.  

Inflation at the beginning of our universe is a pretty well accepted fact now and pretty much replaces the classic BB theory.  The dimensions of space in our universe expanded something like 10^30 times in the first 10^-34 seconds (Check my numbers) (i.e. stupendously fast) and then settled down to expanding at mere light speed.  .

In this theory, this bubble is our universe and some physicists think that our "bubble universe" could be one of many formed by other random fluctuations in the Inflaton field.  In this case, outside our bubble is the Inflation field still expanding.

Any comments or feedback??

Wayne McCraken

On Mon, Jan 23, 2012 at 4:41 PM, Larry Smith <[address removed]> wrote:

Nobody knows for sure, but the consensus seems to be leaning towards the concept that space isn't the simple concept we've assumed all along.

Don't confuse the fact that we can mathematically describe space as a grid that goes on forever, with a possible physics "object" (space) that is finite (though enormous in human terms) in extent.

For example, we know that due to the uncertainty principle, "empty" space isn't empty at all, but is full of (evanescent) virtual particles, popping into and out of existence.

So maybe we should be thinking, very very very roughly, as our

--
Please Note: If you hit "REPLY", your message will be sent to everyone on this mailing list ([address removed])
This message was sent by Dave Noel ([address removed]) from The North York Physics Meetup (61).
To learn more about Dave Noel, visit his/her member profile
To unsubscribe or to update your mailing list settings, click here

Meetup, PO Box 4668 #37895 New York, New York[masked] | [address removed]

--
Please Note: If you hit "REPLY", your message will be sent to everyone on this mailing list ([address removed])
This message was sent by Larry Smith ([address removed]) from The North York Physics Meetup (61).
To learn more about Larry Smith, visit his/her member profile
To unsubscribe or to update your mailing list settings, click here

Meetup, PO Box 4668 #37895 New York, New York[masked] | [address removed]

--
Please Note: If you hit "REPLY", your message will be sent to everyone on this mailing list ([address removed])
This message was sent by Chandiran Homer ([address removed]) from The North York Physics Meetup (61).
To learn more about Chandiran Homer, visit his/her member profile
To unsubscribe or to update your mailing list settings, click here

Meetup, PO Box 4668 #37895 New York, New York[masked] | [address removed]