Starship Asterisk*

Hello Qev

Your right in what you say.

I'm just wanting to know the extent if any.

I just cannot see the extent and being responsible for if any of the expansion of the visible universe.

Even the redshift and the hubble constant is in question.

Hi Harry,

The existance of the Casimir effect implies that even so-called empty space has a certain energy density. This ties in well with certain dark energy theories that also require space to have a non-zero energy density. I'm not exactly familiar with the details of these theories though... a bit over my head.

Hello All

Hello Martin
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http://antwrp.gsfc.nasa.gov/apod/ap040801.html
http://physicsweb.org/articles/world/15/9/6
The attractive force between two surfaces in a vacuum - first predicted by Hendrik Casimir over 50 years ago - could affect everything from micromachines to unified theories of nature.


The above APOD link
states
This tiny ball provides evidence that the universe will expand forever. Measuring slightly over one tenth of a millimeter, the ball moves toward a smooth plate in response to energy fluctuations in the vacuum of empty space.
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Sometimes when I read APOD comments I wander who writes them.
I cannot see the evidence for an expanding universe.

Here Harry -a relative APOD.

http://antwrp.gsfc.nasa.gov/apod/ap040801.html

Hello Qev

Your right its not a new theory.

Its been around for over 50 years or so.
But! in the last ten or so years it has become an important theory.

For many years I spoke only of the Big Bang until I found the negatives with the BBT.

That's actually not a new theory at all; it's one of the new versions of the ekpyrotic theory: the cyclic universe theory if I'm not mistaken. I have no idea why the media is suddenly picking up on this now, since it made its first run through the news back in 2002.

Hello ta152h0

I have been hammering that idea for the last 35 years.

But! that idea has aslo been hammered by many cosmologists.

That artical in the paper was presented to me.

The professor Turok from Cambridge University is no small fry.

Its ok to be suspicious and question it till the cows come home. We all do that. But! never become emotional over any idea.

We all want a theory that will stand on its own two feet and not be supported by fantacy and make up ideas.

harry,
very suspicious this article suddenly appears in your home town newspaper on a subject you have been hammering for as long as I have been privileged to read your posts.

Hello All

News flash. Sydney Morning Herald.
quote:
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"London: The universe we live in may not be the only one but just the latest in a line of repeating big bangs stretching back through time, according to the latest theory from cosmologists.
Instead of being formed from a single big bang about 14 billion years ago destined to expand and eventually peter out to the cold, dead remains of stars, the universe may be an endless loop of explosions and contractions stretching forever.
The latest theory has been postulated to account for what Einstein described as his biggest Blunder"", the cosmological constant, a number linking energy and space, which he proposed to account for the galaxies being driven apart."
Physcists have since than measured the number as too small.
The constant is a mathematical representaion of the nergy of empty space, known as dark energy, which exerts a kind of anti-gravity, pushing galaxies apart at an accelerating rate. It hapens to be a googol(1 followed by 100 zeros) times smaller than would be expected if the universe was created in a single big bang.
According to the new theory, published yesterday in the journal Science, the discrepancy can be explained if the universe itself is billions of years older and fashioned from cyclical big bangs.
people have infered that time began then, but there really wasn't a reason for that infrernce, said Neil Turok, a theoretical physcist at Cambridge University in Britain. " what we are proposing is very radical. Its saying there was time before the Big Bang".
There doesn't have to be a beginning of time, Professor Turok said. According to our theory, the universe may be infinitely old and infinetly large".
If this theory is right, how long have we got until the next big bang?
Professor Turok said " We can't predict when it will happen with any precision- all we can say is it won't be within the next 10 billion years".
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I just read it and thought to post it.

The Big Bang.

Hello All

Can someone give me strong evidence for the Big Bang and strong evidence that the whole universe is exapnding

Hi Pete
that is funny

Hello All

At the start of this thread some questioned the recycling process of the universe.

One questiion was where did the matter come from to start it off.

In my opinion and in the opinion of many cosmologists today is that it has always being here in one form or another.

With that same logic, life in the universe has always being here. Life having the abilty to start and evolve under the right conditions. What evidence have we got. Planet earth.

Now if you think along the lines of the BBT than it came from nothing 14 billion years ago in some magical way having an explosive power from nothing to expanded faster than the speed of light to spread everything out into nothing.

Nothing gets nothing
Something gets something.

Harry - I agree and there are a variety of examples in DAPOD.

Pete - Its been a couple days since I laughed like that -Thanks!

Hello All

Martin your right knowledge is relative.

Sometimes what we think entraps us and stops us from looking beyond.

ta152h0 wrote:everything radiates from our eyeballs

Well, sorry, Mr. Summers, but my eyes can't do that.

<<<6th we think that we are at the center of the observable universe. >>>

simple geometry, we are observing from a point, everything radiates from our eyeballs. word engineering can do strange things to thinking Pass the ice cold one around again.

Ok let’s rewind and replay an order of knowledge….

1st we thought the entire world was solely composed of the land we inhabited.

2nd we thought that the Earth was flat.

3rd we thought that the Earth was at the center of the universe.

4th we thought that our galaxy was the total universe.

5th we think that the total universe is solely composed of our observable universe.

6th we think that we are at the center of the observable universe.


What can one learn from this….Knowledge is relative!

Hello All

The observable universe is actually about 9 huge bubbles of super clusters of galaxies.

The question is this.
This cluster of super clusters: Is there more in the group that we cannot see.? Do clusters form in a similar way far far away.


In ten years or so the hubble will be repalced by a very large telescope.
I cannot wait for the info.

astroton wrote:Qev

Quantum particle behavior is interesting phenomena. Physical laws stand on very limited observations (A snapshot in a life of universe). Years gone by, the gravity may well be defined differently. Big Bang, if it really did happen, may turn out to be only a small bang in a very large picture, obscured today behind our limited understanding and our belief that we know it all.

It's a possibility that beyond the regions we observe, different physics might hold sway, and that there could be different regions undergoing different rates of expansion, and so forth. These are often referred to as 'domains', IIRC. But to the limits of our current knowledge, we have no evidence of such things. So I'll never say that it's impossible that there may be 'multiple' big bangs, the existence of such isn't required by our current theories.

Qev

Quantum particle behavior is interesting phenomena. Physical laws stand on very limited observations (A snapshot in a life of universe). Years gone by, the gravity may well be defined differently. Big Bang, if it really did happen, may turn out to be only a small bang in a very large picture, obscured today behind our limited understanding and our belief that we know it all.

Till then we need to keep an open mind.

Ta

Pass the ice cold one.

there is the " Observable Universe " thru the lens of newtonian physics and there is the non-observable universe thru the lens of quantum physics...........and they co-exist

Martin wrote:Qev, Come on.

Your explination falls short of reality. If you think about it you will see your error. Your misleading others to think there is nothing beyond what we can observe. The bubble is an expansion of matter and energy contained within THE TOTAL UNIVERSE. It sounds like your in agreement but your not making the connection and your tripping over your own words.

Think bubble>>>>>Total universe>>>>>>>bubble>>>>>>Total Universe======not the same!!!

Of course they're not the same thing. You'll note that I referred to this as the observable universe, which is that part of the universe that we are currently capable of observing. The 'local bubble', as you refer to it, isn't a bubble at all; it's simply the sphere defined by the maximum distance we are currently capable of seeing into the distant (and past) universe. According to the BBT, local spacetime isn't expanding into the surrounding universe; ALL of the universe is expanding, everywhere, equally.

According to our current understanding of physics, we see no reason why other parts of the universe, even parts too far away from us to be observed, should be behaving any differently than our local region of spacetime.

Martin wrote:Of course it’s an expansion of matter and energy. When you think about the BB, think about an observable super heated bubble of matter and energy exploding and expanding outwardly. Now ask yourself what is this bubble (i.e. observable universe) contained in -it's called the TOTAL universe. The bubble itself is not the TOTAL universe.

This point of view really misses the point of Big Bang theory, which is summed up in the Big Bang Wikipedia article under "Theoretical Underpinnings":

Wikipedia contributors wrote:the Big Bang is not an explosion of matter moving outward to fill an empty universe; what is expanding is spacetime itself. It is this expansion that causes the physical distance between any two fixed points in our universe to increase.

Basically, space expanded (and is still doing so), pulling matter along with it.

Martin wrote:Qev, Come on.

Your explination falls short of reality. If you think about it you will see your error. Your misleading others to think there is nothing beyond what we can observe. The bubble is an expansion of matter and energy contained within THE TOTAL UNIVERSE. It sounds like your in agreement but your not making the connection and your tripping over your own words.

Think bubble>>>>>Total universe>>>>>>>bubble>>>>>>Total Universe======not the same!!!

As Qev wrote, the "bubble" is in fact the entire observable universe, according to BBT. Your addition of this "total universe" adds an extra layer of complexity to the universal model without resolving any of the questions: if the Big Bang was just an explosion of matter and energy into the pre-existing "total universe", what lies outside this total universe?

Qev, Come on.

Your explination falls short of reality. If you think about it you will see your error. Your misleading others to think there is nothing beyond what we can observe. The bubble is an expansion of matter and energy contained within THE TOTAL UNIVERSE. It sounds like your in agreement but your not making the connection and your tripping over your own words.

Think bubble>>>>>Total universe>>>>>>>bubble>>>>>>Total Universe======not the same!!!