I agree relative simultaneity suggests 13.6 Billion light years but from the time light started towards us the Universe was supposed to be expanding at the speed of light and increasing. If that were the case in reality the Universe is now at least 27 billion light years distance from us. Can this be true?
Inflation is your short answer. The very early universe expanded at superluminal rate.
Perhaps a good source, for which gives a conservative lower bound, is the official NASA print of 5th year WMAP data in Jan 2009. A number of the world's top cosmologists signed off on this (eg David Spergel, Joanna Dunkley, Ned Wright, Eiichiro Komatsu... etc). WMAP is aknown premier project, and they also factored in the other two main bodies of other data (the galaxy count surveys and supernova data if tou care), to give a "WMAP + BAO + SN" result in a separate column of their table. Refer for Komatsu et al.
But the short answer is that the present radius of the observable, if you could freeze expansion so, as to measure it in today's distance terms, is 45 billion light years.
Perhaps a good source, for which gives a conservative lower bound, is the official NASA print of 5th year WMAP data in Jan 2009. A number of the world's top cosmologists signed off on this (eg David Spergel, Joanna Dunkley, Ned Wright, Eiichiro Komatsu... etc). WMAP is aknown premier project, and they also factored in the other two main bodies of other data (the galaxy count surveys and supernova data if tou care), to give a "WMAP + BAO + SN" result in a separate column of their table. Refer for Komatsu et al.
But the short answer is that the present radius of the observable, if you could freeze expansion so, as to measure it in today's distance terms, is 45 billion light years.
dakfe09,
So the relative size is based on the finite speed of light so as to be an illusion like the Lorentz contraction?
So the relative size is based on the finite speed of light so as to be an illusion like the Lorentz contraction?
Any answer that I could give you would be no more than speculation.
Size of the observable universe is based only on the distance measurements from the redshift of very distant objects - which is ultimately the doppler effect.
dakfe09
Yes, thanks.
Yes, thanks.
QUOTE (4Dguy+Oct 2 2009, 12:02 PM)
I agree relative simultaneity suggests 13.6 Billion light years but from the time light started towards us the Universe was supposed to be expanding at the speed of light and increasing. If that were the case in reality the Universe is now at least 27 billion light years distance from us. Can this be true?
Read here. Not that it will help.
Read here. Not that it will help.
The size of the universe only depends on what you consider the universe to be. If you consider the universe to be every thing then its size must include every thing. When humanity wakes up for the new time and realizes how amazing this world really is I think part of that will be realizing the world isnt as small or big as they think it is. You can fit our universe inside my shoe my actual shoe. And yet at the same time its bigger then a breadbox.
QUOTE (magpies+Oct 2 2009, 03:00 PM)
You can fit our universe inside my shoe my actual shoe.
What!, ....your shoe is not part of the universe?!
Are you a God, and if so why do you wear shoes?
What!, ....your shoe is not part of the universe?!
Are you a God, and if so why do you wear shoes?
Yes my shoe is part of the universe but I was not talking about the shoe instead the space it takes up.
[Moderator: Suspended 30 days for lying and for claiming he himself does not belong on this forum.]
[Moderator: Suspended 30 days for lying and for claiming he himself does not belong on this forum.]
The universe is as big as it needs to be. Nothing more. Nothing less.
That said, I do believe there is a case for it being much smaller than we think. I know ... I know ... redshift measurements say otherwise. But just because I have a ruler that say's it's 100 centimeters long doesn't mean that it can't actually be 20 centimeters long.
In other words, if the Standard Model's interpretation of Hubble's data (and WMAP for that matter) are in error by just a small amount then the size of the universe is possibly dramatically different that we believe.
Note: My argument for this assertion is weak and lacks virtually ANY substantive evidence. So far ...
That said, I do believe there is a case for it being much smaller than we think. I know ... I know ... redshift measurements say otherwise. But just because I have a ruler that say's it's 100 centimeters long doesn't mean that it can't actually be 20 centimeters long.
In other words, if the Standard Model's interpretation of Hubble's data (and WMAP for that matter) are in error by just a small amount then the size of the universe is possibly dramatically different that we believe.
Note: My argument for this assertion is weak and lacks virtually ANY substantive evidence. So far ...
If volume is a function of energy verses attractive-forces and nothing else, then does "the universe" refer to the sum total of all matter and energy, or is it supposed to also refer space-time as some kind of container-substance?
Also, if the universe is defined as the sum total of everything, including matter, energy, and space-time, then its volume would not be measurable because it would exist relative to no other volume. You cannot measure something without anything with different amounts of the same properties to measure it against.
Is the expansion of the universe supposed to be a general progression of space-time dilation, which exists as entropy of gravity everywhere? If that is the case, then could black holes be primordial "clumps" of space-time that will eventually "blossom" into normal stars when the universal dilation has reached a certain level? Maybe dark matter is an even more primordial state of space-time that exists as the medium from which black holes are eventually born.
This would ensure the birth of fresh, sufficiently undilated matter-energy after existing stars and other objects have dilated into disintegrated clouds.
But if the universe never reaches the limits of expansion-energy and begins to collapse back on itself, what would cause such a small dense object to form as would have been present at the moment before the big bang?
Was the big bang just one instance of an emergent black hole among many "blossoming" out of its Schwarzschild radius as a result of space-time dilation entropy?
Also, if the universe is defined as the sum total of everything, including matter, energy, and space-time, then its volume would not be measurable because it would exist relative to no other volume. You cannot measure something without anything with different amounts of the same properties to measure it against.
Is the expansion of the universe supposed to be a general progression of space-time dilation, which exists as entropy of gravity everywhere? If that is the case, then could black holes be primordial "clumps" of space-time that will eventually "blossom" into normal stars when the universal dilation has reached a certain level? Maybe dark matter is an even more primordial state of space-time that exists as the medium from which black holes are eventually born.
This would ensure the birth of fresh, sufficiently undilated matter-energy after existing stars and other objects have dilated into disintegrated clouds.
But if the universe never reaches the limits of expansion-energy and begins to collapse back on itself, what would cause such a small dense object to form as would have been present at the moment before the big bang?
Was the big bang just one instance of an emergent black hole among many "blossoming" out of its Schwarzschild radius as a result of space-time dilation entropy?
How big is the Universe?
Fact
The detected mass of the Matter in Universe is so small
(the average density of all substance in Universe
is approximately p=10^-30 g /sm^3) that it cannot
‘close’ Universe in sphere and therefore our Universe
( as whole ) is ‘ open’, Eternal and Infinite Vacuum
( an Absolute Reference Frame )
Thinking to ‘ close’ It astrophysicists say 99% mass
in Universe is ‘dark mass’
Nobody knows what it is
Question
How can 99% of ‘dark mass’ create 1% of visual mass ?
Israel Sadovnik Socratus
http://www.worldnpa.org/php2/index.php?tab...Display&id=1372
===================== . .
[Moderator: Suspended 10 days for linking to crackpot site as if it were a good reference, cutting and pasting preformatted text with line endings, confusing philosophical criticism of a scientific theory with discrediting it, self-promotion and reposting of material from other websites.]
Fact
The detected mass of the Matter in Universe is so small
(the average density of all substance in Universe
is approximately p=10^-30 g /sm^3) that it cannot
‘close’ Universe in sphere and therefore our Universe
( as whole ) is ‘ open’, Eternal and Infinite Vacuum
( an Absolute Reference Frame )
Thinking to ‘ close’ It astrophysicists say 99% mass
in Universe is ‘dark mass’
Nobody knows what it is
Question
How can 99% of ‘dark mass’ create 1% of visual mass ?
Israel Sadovnik Socratus
http://www.worldnpa.org/php2/index.php?tab...Display&id=1372
===================== . .
[Moderator: Suspended 10 days for linking to crackpot site as if it were a good reference, cutting and pasting preformatted text with line endings, confusing philosophical criticism of a scientific theory with discrediting it, self-promotion and reposting of material from other websites.]
QUOTE
Fact
The detected mass of the Matter in Universe is so small
(the average density of all substance in Universe
is approximately p=10^-30 g /sm^3) that it cannot
‘close’ Universe in sphere and therefore our Universe
( as whole ) is ‘ open’,
The detected mass of the Matter in Universe is so small
(the average density of all substance in Universe
is approximately p=10^-30 g /sm^3) that it cannot
‘close’ Universe in sphere and therefore our Universe
( as whole ) is ‘ open’,
as far as my understanding goes, this is not a 'fact' but an area still open for debate.
10^-29 g/cm^3 is an order of magnitude estimate of the critical density required to close the universe assuming basic GR cosmology. 3H^2/8πG, but the estimates of actual density of the universe based on telescopic examination (whether you include inferred dark matter or not) are smaller than this.
That is only true if you believe that God didn't make everything. 
Given any interval at all without a discreet beginning, it's easy enough to construct an 'idealized' point to serve as its real beginning. Similarly for endings.
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