Our Universe -- Observable verses Unobservable Part
How big is our actual universe compared to the part we can see (including all
the astronomical instruments)?
Present Cosmology suggests that the size of our universe is about 1050 times (at least) that of the observable part of our Universe.
The size possibilities vary up to 10110 times the observable part of the Universe.
Let's use the smallest value of 1050.
Some numbers to show how immense this is:
(1) What is the diameter of the observable part in meters?
The radius of the observable part of our universe is 13.7 billion light years plus or minus 1%.
The diameter must be two times the radius or 27.4 billion light years.
How far is that in meters?
Each light year is the distance light travels in 1 year at a speed of 3 x 108 meter / second.
So 1 light year distance = 1 y x 365 days/y x 3600 seconds/hour x 24 hour/day x 3 x 108 meter/second
This equals 9.5 x 1015 meter (m will stand for a meter) that light travels in one year.
For 27.4 billion light year: 27.4 x 109 light year x
9.5 x 1015 m/light year
it is 2.6 x 1026 m
So the diameter size of the observable size of our Universe is 2.6 x 1026 m -- very large, but almost nothing compared to the size of the whole universe!
(2) The size of a nucleus in an atom:
The diameter of the nucleus of an atom (the part that consists of the protons and neutrons) is in the order of 10 -14 m.
Compare that to the diameter of an atom that contains the nucleus, --> in the order of 10 -10 m.
So 10 billion atoms can be lined up side by side to cover the distance of 1 meter.
Or 10 million atoms can be lined up side by side to cover the distance of 1 millimeter.
An atom is really, really small, and the nucleus is ten thousand times smaller.
(3) How many times larger is the observable
part of our Universe compared to the nucleus of an atom?
This is equal to the diameter of the observable part of our universe divided by the size of a nucleus
So 2.6 x 1026 m / 1 x 10 -14 m.
Dividing you get: 2.6 x 1040.
This means that the size of the observable part of our Universe is 2.6 x 1040 times as large as a nucleus of an atom.
(4) Compare the size of the observable
universe with that of the whole universe:
Since the total universe is at least 1050 times that of the observable part of our Universe the number 2.6 x 1040 is about 10 billion times smaller than that number.
If you imagine the size of the observable universe of 13.7 billion light
years to be that of one nucleus of an atom and compare that with the size of the
observable universe, then the total universe is 10 billion times larger than the
size of the observable universe compared to a nucleus of an atom.
Basically what this means is that the part of the universe we can observe (with the best telescopes and the farthest it is possible to see) is almost nothing compared to the immensity that can't be seen.
The unobservable part of our universe is approaching infinity times the observable part.
An addition: This is just our universe that started with a Big Bang 13.7 billion years ago. Modern Cosmology strongly suggest that there are always (even now) new Big Bangs, therefore new universes happening all the time and have been from the infinite past. Ours is just one universe in a multiverse. The other universes could by chance have other basic universal constants than ours.
Mind boggling, eh?
There is even more:
Also check the article by Max Tarmark called Parallel Universes. Click:
An Excerpt from page 4 [my comments in square brackets]:
[Our universe extends indefinitely in all directions -- this means that there is very high probability of our local bubble of 100 light years is repeated exactly, many times a great distance from us - you included with the exact same experiences as you have. Also many more repetitions of a solar system exactly like ours with a very slight variation of what it is right now our solar system, including you. The following is only our universe, and is not even considering parallel universes.]
"A crude estimate suggests that the closest identical copy of you is about 101029m away [a 1 with 1029 zeros after it -- that is 1 with 29 zeros after it, just for the exponent -- that is multiply 10 times 10, 1 with 29 zeros after it times]. About 101091 m away, there should be a sphere of radius 100 light-years identical to the one centered here, so all perceptions that we have during the next century will be identical to those of our counterparts over there [light will take a century to travel 100 light years]. About 1010115 m away, there should be an entire Hubble volume identical to ours [by Hubble volume is meant our whole observable universe of radius 13.7 light years]."
"This is an extremely conservative estimate, simply counting all possible quantum states that a Hubble volume can have that are no hotter than 108 K [ours is 2.7 degrees K]. 10115 is roughly the number of protons that the Pauli exclusion principle would allow you to pack into a Hubble volume at this temperature (our own Hubble volume contains only about 1080 protons). Each of these 10115 slots can be either occupied or unoccupied, giving N = 210115 to 1010115 possibilities, so the expected distance to the nearest identical Hubble volume is N1/3 about 1010115 Hubble radii of about 1010115 meters. Your nearest copy is likely to be much closer than 101029 meters, since the planet formation and evolutionary processes that have tipped the odds in your favor are at work everywhere. There are probably at least 1020 habitable planets in our own Hubble volume alone." [This continues with a discussion of the repercussions]
[A comment on the powers of 10 used in the above
some simple examples:
(a) 10101 means 1010 or 1 with 10 zeros after it or 10,000,000,000
(b) 10102 means 10100 or 1 with 100 zeros after it or 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.
(c) 10103 means 101000 or 1 with 1000 zeros after it or ... you type out 1 with 1000 zeros.
(d) 10104 means 1010000 or 1 with 10,000 zeros after it.
These numbers are stupendously large!!! BUT the numbers used above are much, much larger!
Now: try 101029 or 1010115 .]
What a time to live and discover!
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