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Author Topic: Why is the expansion of the universe speeding up.  (Read 6215 times)

Offline ukmicky

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This aint a new theory , i was just wondering. (it happens occasionally :)

Is this  the reason for the effect that the expansion of space is speeding up the further you look.

.

Two  galaxies A AND B are 1 light year apart
Now letís say 1 light year of space expands by 1 light year every month.

After a month the distance between A&B will have expanded by 1 Light year so A&B will now be 2 light years apart.

But as A & B are now 2 light year apart and As 1 light year of space expands by 1 light year every month you would now see the expansion between A & B accelerating as A & B are now separating by the speed of 2 light year a month

After another month a & b will b 4 light years apart and so if you to measure the speed that A & B were moving away from each other it would be 4 light year  a month and so on and so on.

GO EASY ON ME. ;D



« Last Edit: 26/06/2007 23:35:15 by ukmicky »


 

Offline DoctorBeaver

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Re: Why is the expansion of the universe speeding up.
« Reply #1 on: 26/06/2007 00:01:53 »
Mathematically that would appear to work
 

Offline ukmicky

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Re: Why is the expansion of the universe speeding up.
« Reply #2 on: 26/06/2007 00:06:39 »
Doc Please

Their has got to be something wrong with it as i thought it up. :)

« Last Edit: 26/06/2007 00:14:43 by ukmicky »
 

Offline DoctorBeaver

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Why is the expansion of the universe speeding up.
« Reply #3 on: 26/06/2007 22:30:54 »
I've given this a lot of thought today & I can't find fault with your theory.
« Last Edit: 26/06/2007 22:33:45 by DoctorBeaver »
 

Offline ukmicky

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Why is the expansion of the universe speeding up.
« Reply #4 on: 26/06/2007 23:27:56 »
Cheers Doc
I cant find nothing wrong with it either but my track record is littered with things that i thought were fine that turned out to be a load of crap.

But it makes sense to me ,

Im waiting for Ian to blow holes in it.  ;D

« Last Edit: 29/06/2007 20:35:41 by ukmicky »
 

Offline DoctorBeaver

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Why is the expansion of the universe speeding up.
« Reply #5 on: 26/06/2007 23:36:53 »
Ah, wait a minute. Red shift.

If each lightyear of space that was expanding was doing so uniformly, that would mean that as much of it would be expanding towards us as away from us. Wouldn't that mean that the red shift from distant objects would only be half of what we see? Then again, we use the red shift to estimate how far away those objects are so it would mean that our estimates would be incorrect; the objects would be further away than we thought - wouldn't they?  ???

I've confused myself again  [:I]
 

Offline ukmicky

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Why is the expansion of the universe speeding up.
« Reply #6 on: 27/06/2007 00:08:54 »
Quote
If each lightyear of space that was expanding was doing so uniformly, that would mean that as much of it would be expanding towards us as away from us

No two distant stars in two distant galaxies will always be moving away from each other just like two points on a balloon due to all the space in between stretching.You would still get redshift because the distance between A & B would always be increasing.

Quote
Wouldn't that mean that the red shift from distant objects would only be half of what we see? Then again, we use the red shift to estimate how far away those objects are so it would mean that our estimates would be incorrect; the objects would be further away than we thought - wouldn't they?
  Dont know it is confusing :), but yes it would mean some of their calculations of distance determined by redshift would be wrong.

Looks like i've just rewritten the science books.  Ps dont quote me on that.   [:0];D;D
.


« Last Edit: 27/06/2007 00:11:56 by ukmicky »
 

Offline DoctorBeaver

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Why is the expansion of the universe speeding up.
« Reply #7 on: 27/06/2007 00:50:01 »
*starts writing a Wiki entry for Micky*
 

Offline ukmicky

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Why is the expansion of the universe speeding up.
« Reply #8 on: 29/06/2007 20:34:32 »
Hows my article coming Doc:)
 

Offline DoctorBeaver

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Why is the expansion of the universe speeding up.
« Reply #9 on: 29/06/2007 22:35:15 »
I've got stuck after "This well-meaning but misguided..."
 

Offline Soul Surfer

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Why is the expansion of the universe speeding up.
« Reply #10 on: 29/06/2007 23:08:45 »
Agree with your thinking ukmicky but not your example numbers, They just don't work because they don't fit with any sort of common sense because the separations are many orders of magnitude too small and the expansion rates many orders of magnitude too great.  The Hubble constant is 77 kilometers per second per megaparsec so to put it in your terms the separation of the galaxies is is 30 million light years v the expansion speed is 77 km/sec  or about .00025 of a light year a year.  That is about 250 light years or approximately one ten thousandth of the separation in a million years.
A distance of 30 million light years corresponds approximately to the distance from our galaxy to the nearest supercluster of galaxies in the constellation of Virgo i.e. reasonably local on the scale of the visible universe which is around one hundred times bigger than this.

It is important to get things like this in their true scale perspective.

The bench mark is a uniform expansion with time and distance i.e. the Hubble constant is constant.  Acceleration means that it is going faster as time passes deceleration (which is what you would expect for a conventional explosion because the self gravity of a finite universe would be expected to slow down the expansion) is going slower with time.
« Last Edit: 29/06/2007 23:19:07 by Soul Surfer »
 

Offline ukmicky

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Why is the expansion of the universe speeding up.
« Reply #11 on: 29/06/2007 23:20:10 »
Hi Ian

I'm glad idea makes a bit of sense :) it was just something i was toying with and wondered what other people thought .


Quote
It is important to get things like this in their true scale perspective.

I agree but unfortuanatly, i'm not that clever ;D

The numbers in my example  mean nothing and were just used in the example to explain what i was getting at. I havent got a clue as to what would be correct number wise or how to calculate it. 
« Last Edit: 29/06/2007 23:25:12 by ukmicky »
 

Offline Soul Surfer

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Why is the expansion of the universe speeding up.
« Reply #12 on: 29/06/2007 23:25:18 »
It isn't very difficult it all comes directly from the hubble constant and some simple arithmetic to change the units that it is expressed in and look how things change with time.  The problem is if you don't use reasonably realistic numbers you can get completely the wrong impression of how things fit together.
 

Offline m.levert

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Why is the expansion of the universe speeding up.
« Reply #13 on: 11/09/2007 23:44:40 »
may i humbly submit that the universe could be far,far bigger and older than hitherto imagined?

(big bang theory is a bit cobbled together and cannot predict fundamental constants very well)

the microwave background is only just being resolved, (13 to 15 billion light years equivalent distance) but this is only as far as we can actually see - so there`s either a heck of a lot out there after that, or the universe is finite but unbounded.like a donut ring. mmmm.......

 [?]
 

Offline Soul Surfer

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Why is the expansion of the universe speeding up.
« Reply #14 on: 13/09/2007 23:57:29 »
If initial inflationary cosmologies are correct it is almost cerainly at least tens or hundreds of orders of magnitude bigger than the limits of our visible universe.  A totally unimaginably large size
 

Offline m.levert

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Why is the expansion of the universe speeding up.
« Reply #15 on: 17/09/2007 01:41:30 »
that`s another thing that makes no sense to me- inflation. it just looks like a total fudge, something thrown in to make the figures add up,just like a lot of the other parameters in the theory.

how is it reasonable to propose the universe expanded at such a rate, seemingly many times the speed of light, exponential acceleration, etc.. there would have to have been no trace of matter at all, only energy/electromagnetic fields present - otherwise,the whole expansion front would be dilated out of existence.

one dead giveaway regarding the unreliability of the big bang model is it`s prediction of the cosmological constant to be 100 orders of magnitude different to reality. are we barking up the wrong tree?

i am obviously prepared to face the fact i have totally misaprehended all this, but i think the big bang, far from being the start of everything, was just a (very mysterious) occurence in a much vaster history.

 





 

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Why is the expansion of the universe speeding up.
« Reply #15 on: 17/09/2007 01:41:30 »

 

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