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13.7Billion Year Old Universe, Im Confused!


Harriss

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Hi guys im new here but have a question that i would like answering if possible.

 

So i just read an article on http://www.space.com/17755-farthest-universe-view-hubble-space-telescope.html it says Hubble has managed to look the furthest into the past than ever before, a resounding 13.2billion light years away, with a sequel to the original "Hubble Ultra Deep Field," the "eXtreme Deep Field" or XDF .

 

Now they say the Universe is 13.7billion years old, meaning another .5billion light years more and we see the beginning! if i'm understanding this correctly of course. Now what i'm saying is why doesn't Hubble just turn the telescope around exactly 180 degrees to look a mere .5billion light years away as that would make up the 13.7 billion years, as I am assuming the big bang didn't start exactly where earth is.

 

but then that leads me to think well if Hubble can see 13.2 billion light years away then surly they can see 13.2billion light years away in the 180 degree opposite, which then would mean the Universe would not be 13.7billion years old but 26.4billion years old and counting.

 

if im wrong in my thoughts could someone explain to me where im going wrong :) as i cant get my head round this one.

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Hi guys im new here but have a question that i would like answering if possible.

 

So i just read an article on http://www.space.com/17755-farthest-universe-view-hubble-space-telescope.html it says Hubble has managed to look the furthest into the past than ever before, a resounding 13.2billion light years away, with a sequel to the original "Hubble Ultra Deep Field," the "eXtreme Deep Field" or XDF .

 

Now they say the Universe is 13.7billion years old, meaning another .5billion light years more and we see the beginning! if i'm understanding this correctly of course. Now what i'm saying is why doesn't Hubble just turn the telescope around exactly 180 degrees to look a mere .5billion light years away as that would make up the 13.7 billion years, as I am assuming the big bang didn't start exactly where earth is.

 

but then that leads me to think well if Hubble can see 13.2 billion light years away then surly they can see 13.2billion light years away in the 180 degree opposite, which then would mean the Universe would not be 13.7billion years old but 26.4billion years old and counting.

 

if im wrong in my thoughts could someone explain to me where im going wrong :) as i cant get my head round this one.

 

 

While the Big Bang is thought to have occurred around 13.7 billion years ago that does not mean the furthest object would be 13.7 billion light years away. At some point very early in the life of the universe it is thought to have undergone an expansion that has the effect of the universe being much bigger than 13.7 billion light years across.

 

http://en.wikipedia.org/wiki/Universe

 

http://en.wikipedia.org/wiki/Observable_universe

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Now they say the Universe is 13.7billion years old, meaning another .5billion light years more and we see the beginning! if i'm understanding this correctly of course. Now what i'm saying is why doesn't Hubble just turn the telescope around exactly 180 degrees to look a mere .5billion light years away as that would make up the 13.7 billion years, as I am assuming the big bang didn't start exactly where earth is.

Hi, HubbleHarriss.

 

You ask a very common question in a very unique and insightful way.

 

The Big Bang is consistent with what they call the cosmological principle which holds that the universe is isotropic and homogeneous on large scales. This just means that every direction we look in the sky is pretty much the same as any other direction as far as the density, age, and other basic properties. Here wikipedia talks about it:

 

The universe is now described as having a history, starting with the Big Bang and proceeding through distinct epochs of stellar and galaxy formation. Because this history is currently described (after the first fraction of a second after the origin) almost entirely in terms of known physical processes and particle physics, the cosmological principle is extended to assert the homogeneity of cosmological evolution across the anisotropy of time:

 

...all points in space ought to experience the same physical development, correlated in time in such a way that all points at a certain distance from an observer appear to be at the same stage of development. In that sense, all spatial conditions in the Universe must appear to be homogeneous and isotropic to an observer at all times in the future and in the past.[10]

 

 

That is, earlier times are identical to the "distance from the observer" in spacetime, which is assessed as the redshift of the light arriving from the observed celestial object: the cosmological principle is preserved because the same sequence of evolution is observed in all directions from earth, and is inferred to be identical to the sequence that would be observed from any other location in the universe.

 

If the big bang were an ongoing explosion of matter into space like you're picturing then you'd be absolutely correct—things would appear youngest in the direction of the explosion. But, the big bang is proposed to have happened everywhere at once and everything has been expanding away from everything else since then.

 

The most common way of picturing this is to draw a bunch of dots on a balloon that represent galaxies. When you blow up the balloon every dot gets further from all of the other dots if you measure along the surface of the balloon.

 

It's a fascinating subject that you inquire about in a very unique way so I'm curious if the explanation makes sense to you.

 

~modest

Edited by modest
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i like the infinate universe concept

 

like if we see an galaxy to far away, it appears as cosmic radiation

 

or something similar

 

 

i like to question why

 

why is there a universe

 

why is there matter in the universe

 

why is there time

 

why is there energy

 

 

the thing about the starting date, we may not be taking enough into account

 

big bang, big crunch

 

or

 

multiple universes, bleeding into oneanother

 

but this is the type of question you would ask if you were able to travel the stars in a timely manner

 

you would seek answers to different questions as new data presents itself

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cheers for your replys guys,

 

I don't know if i will ever really understand the workings of the Universe lol.

 

@Modest, your reply with the dots on the balloon made sense to a degree with me, i can understand now that the Bigbang isn't how i first thought but this new knowledge is making my head hurt.

 

A Balloon will pop when it expands to much, so is it the universe that is expanding or is it the stuff inside the universe that is expanding? for people to say the universe is expanding, wouldn't they need to know how big the Universe is(not was), i read that everything everywhere started of at a finite spot and just expanded (faster than i could explain right now), and the universe is expanding not just expanding, but accelerating faster and faster and faster, but whats it expanding to? lets say if i blow up a balloon that will never pop, the four walls in my lounge would stop said balloon expanding passed them , also the balloon is surrounded by space, so surly there should be something surrounding our universe for it to expand into? maybe its expanding inside another universe which is also expanding, that way it would be an infinite cycle , that would make sense to me lol.

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cheers for your replys guys,

 

I don't know if i will ever really understand the workings of the Universe lol.

 

@Modest, your reply with the dots on the balloon made sense to a degree with me, i can understand now that the Bigbang isn't how i first thought but this new knowledge is making my head hurt.

 

A Balloon will pop when it expands to much, so is it the universe that is expanding or is it the stuff inside the universe that is expanding? for people to say the universe is expanding, wouldn't they need to know how big the Universe is(not was), i read that everything everywhere started of at a finite spot and just expanded (faster than i could explain right now), and the universe is expanding not just expanding, but accelerating faster and faster and faster, but whats it expanding to? lets say if i blow up a balloon that will never pop, the four walls in my lounge would stop said balloon expanding passed them , also the balloon is surrounded by space, so surly there should be something surrounding our universe for it to expand into? maybe its expanding inside another universe which is also expanding, that way it would be an infinite cycle , that would make sense to me lol.

Let's hope it doesn't pop :D

 

The balloon thing is just an analogy—helpful, but problematic when taken too literal. The problem is that the universe is 3 dimensional and the surface of a balloon is 2 dimensional. That is to say, you can make a 3D model in the universe but only draw a 2D picture on the surface of a balloon. We're supposed to imagine that we are 2D creatures living on the surface of a balloon and from there we would see all the other dots on the surface get further away over time even though the 2D surface doesn't have a center from which everything is expanding.

 

As for what we're expanding into, some people say nobody knows and some people say the expansion is intrinsic and we're not expanding into anything at all. We know the universe is expanding on cosmic scales because far away galaxies are moving away from us. The further away a galaxy is the faster it's receding (just like the dots on the balloon). It isn't that we see the whole universe getting bigger, it's just that everything we see is getting further from everything else.

 

In the very distant future there should be no other galaxies around at all. They will have all receded pretty much out of sight. Terribly lonely it will be for future civilizations :(

 

~modest

Edited by modest
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A Balloon will pop when it expands to much, so is it the universe that is expanding or is it the stuff inside the universe that is expanding? for people to say the universe is expanding, wouldn't they need to know how big the Universe is(not was), i read that everything everywhere started of at a finite spot and just expanded (faster than i could explain right now), and the universe is expanding not just expanding, but accelerating faster and faster and faster, but whats it expanding to? lets say if i blow up a balloon that will never pop, the four walls in my lounge would stop said balloon expanding passed them , also the balloon is surrounded by space, so surly there should be something surrounding our universe for it to expand into? maybe its expanding inside another universe which is also expanding, that way it would be an infinite cycle , that would make sense to me lol.

Yes, as Modest has said, the balloon is only an analogy. Yet one well enough to visually describe the situation that this is often used in teaching college Astronomy courses. One does not have to worry either about the balloon that is in your imagination from popping. ;-) As in most topology settings the rubber sheet in which you can deform is allowed to "stretch" infinitely without worry.

 

In the case of observing the furthest out via Hubble being 13.2 Billion Years is fine. What is important to note is that it should always be less than the estimated age of the universe since the Big Bang event. How you get an estimate of 13.7 Billion is from now your in simulated fashion run the "movie" of creation from now backwards to an event where it all started. This difference in time is the value (best estimate of 13.7 BY). I know you are going to ask... Why you can not determine where this center of creation is relative to where we are now is from that same balloon analogy. On the surface of the balloon. There is no special place more important than another. It all looks homogenous (same). So from what we see, we can not tell where it was.

 

To further complicate matters is that now a faction of Cosmologists are considering that a "before" the BB event may make sense. I know that sounds weird. Yet there it is! :interesting:

 

maddog

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Welcome to hypography, HubbleHarris! :) Please feel free to start a topic in the introductions forum to tell us something about yourself.

A Balloon will pop when it expands to much, so is it the universe that is expanding or is it the stuff inside the universe that is expanding?

The idea that, as its expansion continues without limit to increase, the universe will “pop”, is actually a serious cosmological hypothesis, known as the Big Rip.

 

As you may by now have gathered, what’s expanding due to the “metric expansion of space”, as cosmologists like to call it, isn’t any actual substance, but the distance between things, in a way that can’t be accounted for using ordinary physics. That is, all the bodies in the universe weren’t simply given an initial outward velocity by an explosion, after which they’ve been gradually slowing due to their mutual gravitational attraction, rather something is effectively pushing them. There’s no compelling theory of what is actually doing this (or even it it’s really happening, rather than everybody somehow misunderstanding something very fundamental about the universe), but it’s possible to calculate, based on observing the universe, how much physical work it’s doing, so it’s called dark energy. In physicist speak, “dark” refers to undetectable, while “energy” is a beautifully well-defined term for the potential to perform physical work that goes back to Isaac Newton’s days around the turn of the 18th century.

 

for people to say the universe is expanding, wouldn't they need to know how big the Universe is(not was),

Its’ complicated, but no – if you can see distant objects, you can figure out if the universe is expanding without having to take measure it, wait a very long time, an measure it again. A simple before-after measuring should work, but we humans have a dislike of experiment with “then wait a very long time” steps in them

 

lets say if i blow up a balloon that will never pop, the four walls in my lounge would stop said balloon expanding passed them , also the balloon is surrounded by space, so surly there should be something surrounding our universe for it to expand into? maybe its expanding inside another universe which is also expanding, that way it would be an infinite cycle , that would make sense to me lol.

Maybe – until those walls or other balloons are close enough that light (visible or other kinds) from them can reach us, there’s simply no way to tell.

 

Astronomers have looked carefully for evidence of such things, but to date (and more mind-bending stuff, such as our universe bending back around on itself like a 4-dimensional globe), but not yet found any.

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This is all a good read guys, i'm glad i found this place, think i will stick around for a bit. :)

 

 

Astronomers have looked carefully for evidence of such things, but to date (and more mind-bending stuff, such as our universe bending back around on itself like a 4-dimensional globe), but not yet found any.

 

This is something i have thought about but couldn't get the words to explain my thoughts, in my mind the 4d globe would look like a doughnut, not expanding but simple going round and round,

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A Balloon will pop when it expands to much, so is it the universe that is expanding or is it the stuff inside the universe that is expanding? for people to say the universe is expanding, wouldn't they need to know how big the Universe is(not was), i read that everything everywhere started of at a finite spot and just expanded (faster than i could explain right now), and the universe is expanding not just expanding, but accelerating faster and faster and faster, but whats it expanding to? lets say if i blow up a balloon that will never pop, the four walls in my lounge would stop said balloon expanding passed them , also the balloon is surrounded by space, so surly there should be something surrounding our universe for it to expand into? maybe its expanding inside another universe which is also expanding, that way it would be an infinite cycle , that would make sense to me lol.

HH,

 

I think maybe you take this analogy a bit too far. Your first question, actually is a great question "what is expanding?", the answer to which is not yet really well known. The breakdown occurs because we in science do not have a good understanding of what space-time (I hyphenate it to show I'm using the Einsteinian way of think about space and time) really is or how it works. Without that you can not easily describe what is expanding. It is clearly not just content (stuff in the universe). But what else is it? This is also where the linkage between General Relativity (Einstein) and Quantum Mechanics (Bohr, Schroedinger, Heisenberg, et al) also breaks down. These two branches of physics do not work well together. So in the case of a balloon in your room expanding would not get constricted by the room because the room would expand also (along with the balloon). It is still a mystery why the expansion of the universe is accelerating forward in time. The "stuff" labeled "Dark Energy" is what has been attributed to why this expansion is accelerating, yet no one know what this Dark Energy is or is made of or why it drives the accelerating expansion.

 

I hope I haven't exploded your mind yet, though I do think it is the mind that in the end be the Only item that keep up with this accelerating expansion of the Universe. B)

 

maddog

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HH,

 

I think maybe you take this analogy a bit too far. Your first question, actually is a great question "what is expanding?", the answer to which is not yet really well known. The breakdown occurs because we in science do not have a good understanding of what space-time (I hyphenate it to show I'm using the Einsteinian way of think about space and time) really is or how it works. Without that you can not easily describe what is expanding. It is clearly not just content (stuff in the universe). But what else is it? This is also where the linkage between General Relativity (Einstein) and Quantum Mechanics (Bohr, Schroedinger, Heisenberg, et al) also breaks down. These two branches of physics do not work well together. So in the case of a balloon in your room expanding would not get constricted by the room because the room would expand also (along with the balloon). It is still a mystery why the expansion of the universe is accelerating forward in time. The "stuff" labeled "Dark Energy" is what has been attributed to why this expansion is accelerating, yet no one know what this Dark Energy is or is made of or why it drives the accelerating expansion.

 

I hope I haven't exploded your mind yet, though I do think it is the mind that in the end be the Only item that keep up with this accelerating expansion of the Universe. B)

 

maddog

 

yes i understand now that i took that analogy to far , to literally, I'm a Noobie when it comes to astronomy and cosmology and wish i had taken a career in the field when i was a bit younger, but now will have to get as much info of you guys and try( used very loosely) to put things into perspective in my mind and maybe one day will be able to share my knowledge with someone who wants to know :)

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yes i understand now that i took that analogy to far , to literally, I'm a Noobie when it comes to astronomy and cosmology and wish i had taken a career in the field when i was a bit younger, but now will have to get as much info of you guys and try( used very loosely) to put things into perspective in my mind and maybe one day will be able to share my knowledge with someone who wants to know :)

HH - np. What gave me the interest was Black Holes was a new and breaking story while I was in High School. It was that excitement and interest that propelled me into science and college. I didn't make it all the way to a professorship at a university and pure research. I instead changed careers to an engineering profession to make more $$. However, my interest has never waned. I will answer when/where I can. Everybody started as a "newbie" sometime in their life. :D

 

maddog

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  • 5 months later...

Hi guys im new here but have a question that i would like answering if possible.

 

So i just read an article on http://www.space.com/17755-farthest-universe-view-hubble-space-telescope.html it says Hubble has managed to look the furthest into the past than ever before, a resounding 13.2billion light years away, with a sequel to the original "Hubble Ultra Deep Field," the "eXtreme Deep Field" or XDF .

 

Now they say the Universe is 13.7billion years old, meaning another .5billion light years more and we see the beginning! if i'm understanding this correctly of course. Now what i'm saying is why doesn't Hubble just turn the telescope around exactly 180 degrees to look a mere .5billion light years away as that would make up the 13.7 billion years, as I am assuming the big bang didn't start exactly where earth is.

 

but then that leads me to think well if Hubble can see 13.2 billion light years away then surly they can see 13.2billion light years away in the 180 degree opposite, which then would mean the Universe would not be 13.7billion years old but 26.4billion years old and counting.

 

if im wrong in my thoughts could someone explain to me where im going wrong :) as i cant get my head round this one.

I would like to protest the move of my reply to the "strange claim forum". My assertion is MUCH more observational evidence of the facts than any other claim to the contrary.

Just as 2 + 2 = 4... if you can observe light coming from galaxies 13 billion light years away in one direction and can also see light coming from another galaxy 13 billion light years away in the opposite direction then mathematics requires 13 + 13 to equal 26 billion light years. Especially because of the fact that those galaxies are BOTH moving away from the observer.

Just because someone "in charge" thinks that to go against something they have "learned" in the cloistered halls of conventional physics dogma is forbidden, doesn't mean that their opinion might not be wrong. Especially when those conventional theories are based on NO scientific evidence. Nor does it automatically mean that every other opinion or statement is wrong. And to say that unproven theories like The Theory Of Expansion are correct without any observational evidence to prove the theory is much more of a "Strange Claim" than one that uses strictly simple observational EVIDENCE to make a counter claim.

Who ever decided to move my reply there should be ashamed of themselves for trying to censor any opinion but their own. That type of censorship should be left in the realm of religion.

:angry:

But to be fair I will allow you to produce your scientific (observational) evidence that would show that my assertion is incorrect.

Edited by Natural
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Your post was moved to the strange claims forum because it is, indeed, a strange claim. Your premise is false; there is no mathematical reason to add the times taken for light to arrive here from opposing areas of the sky in order to arrive at the age of the universe. Rather than being supported by observed evidence, I think your premise is indicative of a misunderstanding of modern cosmology basics. May I recommend reading Ned Wright's Cosmology FAQ, specifically this question. For more of an overview of modern cosmology, try his broader Cosmology tutorial.

Edited by JMJones0424
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