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How Big is the Universe?

S. Mithra
S. Mithra

The current, observable universe has been determined to have a width of 156 billion light years, with an error of less than 1%, by the latest deep-space telescope WMAP. At first, it might seem impossible that scientists are so sure of this astronomical measurement, but this figure has been narrowed by years of research and determined by several paths of inquiry. Also, the size of the universe is intimately dependent on its shape, age, acceleration, and total mass, so we are very confident in this figure.

In 2003, the Wilkinson Microwave Anisotropy Probe sent back enough data for scientists to publish extremely dependable studies that established two previously unknown facts. They determined that the universe is flat, which means standard Euclidean geometry is valid on the largest scale. This can be understood by saying a straight line more or less stays a straight line for as long as it extends. They also established that it is accelerating at an ever-increasing rate, which means that all mass is flying away from each other at faster and faster speeds. The WMAP data measured the temperature, called the cosmic microwave background radiation, of our observable universe with an unprecedented accuracy, to within a 5% error. From these facts, we can deduce figures such as its radius.

Deep-space probes collect data while in orbit to help determine the size of the universe.
Deep-space probes collect data while in orbit to help determine the size of the universe.

Remember that the size of the universe is not a constant value, nor is it the size of an object as we traditionally understand it. It is actually the size of space itself, and as space expands, so does the space between planets, stars, and galaxies. At the beginning of the universe, the Big Bang created space and time as we know them. From that moment, space has been expanding, so we find its size by measuring how far light could have traveled since the Big Bang, along with how much space itself stretched.

Large observatory telescopes can see the universe's "horizon".
Large observatory telescopes can see the universe's "horizon".

We can only possibly look or communicate up to the edge, or "horizon," of where light has traveled since the beginning of the universe. The size of the universe means the space in which we can interact with anything. We will never ever know what is "beyond" this boundary, because there is no way to know anything about it, so it's illogical to consider the realm "outside" of our universe, or to wonder what we are expanding "into."

Outer space.
Outer space.

An independent measure of the size of our universe can be given by studying the oldest stars. The oldest stars we have found are probably somewhere between 11 and 14 billion light years old. If we had stars older than the largest distance light could have traveled, then we'd know there was something wrong with our calculations; there would not be enough time for them to evolve.

Discussion Comments


These are always big questions in my mind. These are:-

1. Why the universe is infinite and having unlimited boundary?

2. Why does it have no ending point?

3. Why are the earth and other planets in rotation/spinning around?

4. Why is the earth magnetic?

5. Why is life only on the earth?

6. Why is there good and bad around us?

7. Why is there every necessary materials/commodities for the living creatures’ right from water, air to everything? How and why are there gravitational forces?

There are thousands of questions driving in every human mind. Let’s discuss on point No.-1.

Till today, through continuous tireless working, scientists hardly claimed that they have determined the observable universe covering156 billion light years only. Space scientists are quoting that it is with an error of less than 1% that the observable universe was was created 14 billion years ago. Then what is beyond this 1% of our knowledge?

Till today no scientists claimed that human being has already reached out beyond the solar system, whereas there are billions of solar systems and galaxy existing in the universe as per information gained by the space science. It’s like an octogenarian set out on foot to cover 200 countries. Carry on discovery through gathering wisdom, knowledge, research etc. but do not disregard the words of God. In fact, the graceful rotation of the earth makes our planet to friendly to life, allowing most parts of earth to stay a nice, comfortable temperature as they are bathed in sunlight during the day and darkness at night for taking rest.

The world and the life (there is no life except the world around created by God as per available reports) is such a beautiful creation that cannot fully explained by the human words/thinking is only next to heaven. Though human wants are unlimited, nothing is lacking for human beings in this world. The only reason for nothingness/poor in the world is because of selfishness/envy/communal and other characters of the evil forces. Lastly still is the question of why the universe is infinite? I want satisfactory answers and to fill the gap of knowledge.


Like I've always been saying, the steady state theory is more realistic. With respect to space, right on. What you see is what you get, and as long as space is excluded as a real quantity, physicists will never put it together.


Space was never created; it already existed, Scientists should try to unlock the question of how space is created and when they say space was created by big bang, I have an obvious question - where did big bang came from or whatever constituted big bang, either the protons or atoms, where did those come from?


We are not at the center of the universe. We are only at the center of our visible portion of the universe. If our galaxy were in a different locale, I suspect the picture would be very similar. Who cares if the universe has a skin? If it does, we obviously can't see it yet.

I have studied gravity, em energy, mass and the universe for some time now, and apparently my thinking is outside the box, because I believe the universe is not expanding. Also much of my understanding of these things varies significantly from the main stream.

No matter where we are in the universe, the visible limit is with us. I know the universe is much larger than we can see and I know what is required to see it. Does anyone out there understand what I am saying?


Stop trying to encapsulate the universe. Scientists must have boundaries to calculate things. Think outside the box. There is no boundary to space, the known universe is infinite; beyond the horizon is infinite space expanding.

Have you ever walked down the street on a late summers day, the sun behind you, and stretched before you is your shadow? Have you ever tried walking faster, then running in attempt to catch the shadow? That shadow is our universe.


The Universe is an estimated 76 Quintillion miles.

This number looks like this. 76,000,000,000,000,000,000.


What puzzles me (and I welcome any explanation) is our (i.e. our Solar System's) position in the Universe. Scientists estimate the size of the universe by looking in to deep space and calculating the distance of the furthest star or galaxy. So in how many directions have they looked?

If they have looked in many directions and the answer is the same that would place us at the center of the universe which I feel is unlikely considering our position within our galaxy.

Even more puzzling would be the shape of the universe if these measurements give different values. Any thoughts anyone? anon15029 are you still about?


by searching we can't find out God for we human beings are nothing -- far more than nothing in the eyes of our Creator -- the one who assembled this universe together. let us appreciate the fact that the universe is too big for us to find out and in fear and reverence worship Him who made the universe and holds it together and that is God.


but the recent comment questions me as i am a computer engineer that what mi8 the program space outside this recursive universe function is: infinite volume or are we living in a virtual universe like a kaleidoscope? anyone obsessed with this stuff and tries to explain in their arts of study is certainly a wise geek. hey I'm not being a hypocrite here.


this is interesting but a maddening stuff, but it looks like the universe is recursive in both space and time. Well, can't overrule the parallel universe concept or nerd paradox thing.


the universe has always existed and always will exist. bottom line!


there's no way to figure it out. it makes my mind spin to even try and grasp it. sure we can figure out the "observable universe, but come on, the whole thing?


Some important things to note in this article. 1) the size is not a constant value and the universe is expanding at an increasing rate. So glava and others, that's how we get 156 billion light years: space is expanding, not simply light is 'traveling' or pushing out 'boundaries' of the universe (as yet a nonsensical concept).

2) For everyone trying to say something about god, and especially those saying hints like he could snap his fingers and do X: do you truly think the being you are positing as the Instigator and Sovereign of the Multiverse is a male humanoid of a bisexual, earthbound species with ten fingers and a badly designed lower back and eyes? (even octopus have better eyes than humans).

As one who accepts scientific method is important, I cannot reject the hypothesis that our universe of 14ish billion years old was created by an entity that created itself without evidence, but I can reject much of the tosh spouted by religion, be it ancient Egyptian, ancient Israelite or modern evangelical Christians.

Foremost that the Creator is a humanoid, whether with a jackal head or human lower back. And that god is simultaneously omniscient and omnipotent. A god that knows all means one that knows the vector of every subatomic particle and every decision by every life form from the first picosecond of existence to the last - which means a being that has no power to change anything, because it is doing naught but running through a set pattern.

Science is a method, a manner if examining your ideas against reality to see if thy hold water. It is not a belief system, it is not a theory. It is a manner of testing your beliefs and theories.


@anon135079 you said God needed no other light to light the universe because "God is light". Well if that is the case then when God said let there be light He created himself. or maybe just one aspect of himself?


i think it is impossible to measure the universe because it is infinite. after some years they will conclude that 156 is wrong and come up with a new number. i personally feel our universe is inside another universe and that inside another. This goes on infinitly!


anon86394: You ask, "The Bible says that God created day and night on the first day, but the sun and moon weren't created until the fifth day. What did God light the Earth with on days one through four if we had no sun until day five?"

The Bible also says that "...God is light...", ergo, He needed no other light to 'light the Earth'. If you are going to base a position upon your perspective of what scripture says, please be kind enough, and intelligent enough to have read the book you are arguing against first.

Whether one believes or dismisses the 'factuality' of scripture, it is foolish to do so without having read it.


There is no presentation of evidence to 'prove' either the big bang theory or the intelligent design theory. By definition, science can neither demonstrate nor prove the age of the earth. The scientific process demands repetition and verification to have any 'actual' value in this discussion. It is theory, people. Nothing more.

So believe what you will. The only stupid position in this argument is to believe that one can prove any position in this argument.


@amypollick : you are more than welcome. Anytime.


@GreaseMonkey: Again, thank you for your comments. I do appreciate you airing your views. Take care.


@amypollick: Actually yes, if you believe any word in the Bible to represent the truth and come here to defend it, then I believe you to be completely incapable of profound, intelligent thought. This is not a forum on faith, this is one about the nature of the universe and your response -- somehow trying to justify why the crap in the bible is scientifically foolproof -- is out of place.

Yes, we have opposing views on the Bible and i most certainly do not have to respect yours. As a matter of fact, no one should have respect ignorance. Like I said, if you are here to defend your little book of anecdotes, go to the appropriate forum with the appropriate audience.


@GreaseMonkey: Thank you for your comments. It is indeed a privilege to be able to disagree with each other civilly and with respect.

The only reply I will offer is that you and I both know I meant "each scientific development in detail" when I used the term "scientific minutiae."

Also, I think you might be quite surprised at my ability to consider weighty subjects. I did not show any disrespect to the poster I replied to. I would appreciate you not making the assumption that, because I read the Bible, I am incapable of serious thinking. If you notice, I have certainly not been disrespectful to you, either, even though we disagree.

We have opposing views on the Bible. So be it. Peace and blessings to you.


@amypollick: The minutiae of scientific development? The bible is hogwash. Those minutiae you refer to have been more successful in answering questions about our existence than the bible which is based on myth, anecdotes and metaphors to explain existence and being. If I were you, I wouldn't over-exert my mind with such deep thoughts. Go back to reading your bible.


So to follow up on what another user said "what is beyond the boundary of the universe?" Where does it "end"? What are we expanding into? I wonder if those are questions that go beyond our level of comprehension or if they can even be asked.

After all, we can only study, measure, comprehend and see up to what the parameters are that make our universe, our existence, as we know it, possible. (i.e. where light can travel and can be measured, where space as we know it goes). The anthropic principle applies here. We cannot possibly know what is beyond what existence is (and as of now, existence means an area where light can travel to and where space-time exist as we know it).

Maybe the laws of the universe, the constants, change as we move into this realm.

The curiosity remains though, which is what is after the great beyond? Where does the universe end? What is at it's edge? This requires us to ask the question of "What is existence?" (if we define existence with the narrow parameters with which we know existence to be).

If we assume the weak anthropic principle (i.e. values of physical constants are given) then the universe must be contained in something.

Maybe it doesn't have to be. We as humans think in terms of space and boundaries, but these are incredibly narrow views or what some call observational biases.

Maybe at its boundaries, space and time and physical constants as we know cease to exist and other constants become the reality. Beyond here be dragons. I think we are venturing into a realm that we cannot possibly comprehend or even if we do comprehend, we will never be able to prove or see as we are limited by virtue of our nature.

We will not know - not with this corporeal condition form and way of existence.


A bit of negative talk, but on metaphysical note I really think the whole "meaning of life" is a distraction filled mainly with thoughts of money, fame and power (over other humans) when the real proper question of our existence and the meaning of the universe lies beyond this mortal life.

Perhaps we are sent here on a discovery journey like a science experiment, given this life form and infinite outcome variables to study existence in this corner of the universe. I do honestly think truth and freedom lies on the other side of the grave.


So the universe is expanding. Would every scientist feel better if it were standing still? The big bang is a theory built on bad science. The galaxies 156 billion light years away may not even exist anymore. If it takes 156 billion years for us to receive light from them, who can say what is actually happening now.

The gamma ray burst that will wipe out this little planet may already be on the way, since the nearest star to earth is Alpha Centauri which is 4.37 light years away. And even if the sun were to explode we wouldn't know it for at least eight minutes.

The universe is, was, and always will exist. man won't, but the universe will. And the universe isn't really expanding. If it were galaxies wouldn't be colliding, they would be moving away from each other. Check your science. There's a huge galaxy going to collide with the Milky Way in the distant future, so how is it all expanding?


When I was a child, I asked my father: "How big is the universe? Does it has a boundary? Even it is an ever expanding boundary?" My father answered: "Then what do you think is outside this boundary?"


I have a few points of confusion on this whole universe size thing. The way I understood it, Einstein's life's work was all about defining objects from specific points of observation. Are we to believe that the size of the universe can be derived from any point of observation? Or are we asserting the weaker localized version?


@Anon86394: Not to get into a dispute about the existence of God, but just to correct a common misconception. Those who wrote the Bible had no thoughts that the earth was flat. That's a concept that didn't come along until the Dark Ages, when scholarship nearly died out in the Western Hemisphere. There are passages in the Bible that speak of the earth as being round. Isaiah 40:22 says, "He sits enthroned above the circle of the earth..." The Hebrew word translated "circle" literally means a globe or sphere, in a three-dimensional sense.

Also, the authors of the Bible were not much concerned with whether the sun or the earth was the center of the universe. However, such notable astronomers as Ptolemy and Aristotle theorized the earth was the center of the universe. Even the Mesopotamians, a fairly advanced people, believed it.

So saying the Bible is false because some of the writers may have believed in a geocentric universe is a little disingenuous at best. The Bible recounts the actions of God in the history of man, not the minutiae of the development of scientific thought.


The Bible says that God created day and night on the first day, but the sun and moon weren't created until the fifth day. What did God light the Earth with on days one through four if we had no sun until day five? The Bible isn't the word of God. It is man's feeble attempt to explain a planet and a universe they didn't understand.

Remember that the same people who wrote the Bible also believe that the Earth was flat and the center of the universe.


Some say it is a matter of faith, that evolution is based on a theory or belief that man descended from some primordial life form (translation: a monkey) and generally progressed in intelligence and ability over billions of years. However, science reveals that our closest relative is, in fact, the chicken.

Creation is also a faith, a faith in an omnipotent, omniscient God who created the world in six days, and the Bible says " The evening and the morning were the first day" and so on.

If I were given a choice to choose between a man who is not perfect and an all powerful being that is, the answer is logical, I'd choose God.


In the big bang, what exploded? No one can tell me, because no one was there eons ago, except God.


i don't know what I'm talking about but my theories are that the mighty god sacrificed him self as we know and it's the big bang from that the created the universe.

from the big bang it created stars and planets and every stars and planets have their own god. the mighty god created all other gods.

like mother earth is a god and she created all and like forms on earth and the sun have their own god too. well everything has their own god.

i don't know but thank you for reading.


The big bang theory is just that -- a theory. It cannot be proven. It's just an idea based off of the current knowledge today. They were convinced the world was flat until they got more data.

Then they were convinced earth was the center of the universe, and again we got more data.

Theories are theories because it's the most educated answer we have. We may never know what started the universe, or if it ever did start in the first place.

The idea of arguing between science and religion will always be at a standstill. There is no hard evidence on either side to prove one's point. For the fellow science guys out there, remember we are scientists and science is never fact. We are in the business of constant learning.

Don't think just because we have a little bit of data that it automatically means we completely know what we are talking about. Human error is prevalent, calculations can and will be wrong.

To those of the religions, stop closing your minds to all possibilities other than your one true gods. Just like science, all your beliefs are theories. This can be seen in that there are multiple religions with multiple gods which all claim to be the one true god.

None of us can be certain of anything and to act like we are certain makes us just as dumb as the people who once said "the earth is flat."


Nowhere in the bible does it say the earth is just 6000 years old. However, from the evidence, the human race is approximately 6000 years old. The earth, stars, and universe was here long before man was created.


To all you bible bashers: According to your fairytale, the earth is about 6,000 years old. However, through scientific research and physical evidence, we have discovered that it is actually around 13,700,000,000 (13.7 billion) years old. Our universe and ourselves are here and yes I agree something did create that.

However, your book's version of events is wrong! We don't know what or who or why and we probably never will but what we do know is that your book was a story created by mere men who used it and 'God' to create fear in people so as to have control over them.

That's the reason behind any religion: control. He who has control has power. I think all religions should be banned and we should work together instead of our little groups (mainly controlled by religion) thinking that they each own the piece of earth they're on and the resources that are in it. As residents of earth, we all 'own' the oil. We all own the gold. We all 'own' the land. None of us asked to be here and not one of us has the right to say that another can't have something that is in this earth of ours. The sooner we all realize this, the better off we'll be.


Why can't you believe in science and believe in God? Why do people argue that they are right? Everyone is entitled to their own beliefs? If you put your trust in science, great. If you put your trust in God, that's great also.

Commonly, we have bigger issues to deal with. If I believe in God or if I believe in the big bang. It doesn't change anything.

A man can believe in God, fear God and still do unthinkable horrors to his neighbor in the name of God. The same could be said about a man of science. Just because someone someone is smart doesn't mean they are incapable of doing great harm. Let us not forget that E=MC^2 was developed by einstein and was the basis for Hiroshima.


Who ever says that if we don't believe in god we will go to hell is wrong because god loves us all no matter how we are. whether we believe or not he still loves us and he is all forgiving so he won't let us go to hell! god isn't suppose to punish!


For those of them who believe in God, I've one simple question.If God Created human beings then who created God?

Science has been able to provide infinite evidence to show that how evolution has happened over years to get to this stage of earth. If God created earth, they why did he create a world with only a limited number of resources? If he does good only, then what happens when all resources are exhausted?!

Think practical. There is not a bit of single evidence of God in the past two centuries and you want to just believe in him?


I think you have been misinformed JayJayWuv - the Bible was not bestowed upon prophets. It is a collection of stories written by various people at different times, which were finally assembled into a single book in the 4th or 5th century AD. There were a lot of stories floating around at the time and the process of deciding which of them should be included in the book, and which should be discarded, was made by a group of men. These men picked the ones that most closely conformed with their particular beliefs at the time, and the others were simply declared to be false.

Believing that this book represents anything other than a collection of fairy tales hand-picked by men with a clear vested interest is doing yourself a disservice. You don't have to believe in invisible magicians just because someone told you to. Educate yourself and shake off this ignorant, superstitious nonsense that is bringing such heartache to the world.


Space, time & all is true... See you all after the next ''big bang'' ... They happen all the time. All the space and all will be true...again always has..always will.


Those people who don't believe in God and question Him will go to Hell. We must never question Him. In Moslem school we learned He has no begginning and no end. The Bible and Quraan is true. It was bestowed upon our prophets. Believe in God. Without Him we'd be non-existent. People this is coming form a 12 year old. To all the people who don't believe in God just believe. it'll do you good.


the problem here is that everyone thinks with a mind that deals with everything having a beginning and an end. It's the way our minds work, but I really think that there was no beginning of the universe as it always was, that is, without a beginning and without an end. that is the only way it can be.


you guys are fun..."i'm right!"..."no! i'm right!"'re all saying the same things but with different words and perspectives.!


Isaac Newton wrote that he believed God occasionally intervened miraculously to set the planets right in their orbits, i.e., to correct cases of minor perturbations.

Today, astronomers no longer invoke "God" to restore orbital perturbations. Neither do they invoke "God" to explain how the elements continue to rise out of fusing hydrogen atoms.

"God" is the biggest intellectual cop out ever conceived and it explains exactly nothing. Every time in history we reach the limits of our understanding, some morons pipe up that God did it and that we will never understand so we shouldn't even try.

Time and again they have been proven wrong as science and progress press forward without invoking miracles or God's magic wand. Please stop spouting your inane, ignorant non-answers.


Just because the big bang coincides with parts of Genesis doesn't mean the Bible must be true. Never underestimate the intelligence of humans two millenniums ago. The only thing that has changed in 2,000 years is the passing down of lessons gained through all of humanities lives and experiences, and the advancement of technology, also the product of experiences passed down, mainly trial and error and evolution. But the overall capacity for IQ has not grown very much. Even as much as it has expanded, the Bible is one of the greatest works of art of all time, hence it's effectiveness. If you think the success of the production car, the light bulb, or Titanic the movie represents the pinnacle of human existence, I beg that you reconsider the Bible. And religion in general.

I don't rule out that God exists. But I guarantee...he doesn't seem like the type of entity who would create man in his own image and likeness, and then his perfect creation consequently betray his maker. And then his maker punish his own creation. And then send his son through a virgin to die to save all of us. All the while denying all other religions from being the true one. Oh and then make man write a book, which is his word. Because you know, he couldn't write it himself, he had to get a man to do it. If you've never watched George Carlin's "Religion is Bull****" video on Youtube, I strongly encourage you to do so.


Some people are so gullible. They'd rather believe in the Bible written thousands of years ago by who-knows-who than believing in science which is based on careful research and self-correcting mechanisms. There is a place for faith and religion in the human culture because that's who we are. And God may even exist. But how likely is it that this God is the one described in the Bible? How about the other religions who worship their own Creators. Obviously, they can't all be right. So has it occurred to these people that they could all be wrong and that God does not exist?


How small are we !!!!


anon14946: We will never see more than this planet because we will destroy ourselves way before we ever get far enough into space to even matter.

Me: No, we'll never get there because we won't be human by the time we -could- get there, according to current understanding of science. Nothing travels faster than light. Unless we can find a way to move the way the Universe does (which is faster but isn't involving the actual movement of matter so it may not be possible) it would take us 80,000 years to reach just the far side of our galaxy (our galaxy is 100,000 light years across, but we're only 30,000 cy from the center of our galaxy so its closer). It'd take millions of years to get elsewhere. Whatever we are, we won't be what we are now by then. Also, if you're referring to all the things that we're doing that threaten to wipe us out (nuclear weapons, global warming, etc), actually we'll likely survive it... well, 1% of us anyway.

anon14721: big bang would lead you to expect expansion in all directions Simultaneously, all particles expanding outwardly spherically. So how can the universe be flat?

Me: The 'Bang' is an easily misunderstood idea. It's not an explosion in the conventional sense (which would leave us with an ever-expanding sphere of matter around a core of nothing). Instead it refers to when matter started spreading out, fast. As for the 'flatness', what that means is that, for the most part, if you travel in a straight line you'll just keep -going- in a straight line without that line being altered. It's not describing every part of the universe, mostly just the huge empty gaps between stars/galaxies where there isn't anything to pull on you.

anon8411: I have been always thinking about the survival of light created by big bang to travel 14 billion years without losing its momentum and force?

Me: Momentum and force are aspects that only get altered by other things. In empty space if you throw a ball it'll go in a straight line and never slow or lose force because there's nothing to slow it down. On earth if you do the same thing there's all this inconvenient air in the way and then gravity pulls it to the ground where there's friction and other objects to get in the way. Light traveling 14 billion cy to get here never had to put up with that.

glava2005: if the universe was created 14 billion years ago the farthest any matter could travel is 14 billion light years in each direction which adds to 28 billion light years across...? so how did we get to 156 billion?

Me: The problem here is one of expansion versus travel. Matter/Energy cannot move faster than the speed of light. However the reason the universe is expanding has nothing to do with moving matter. Space is stretching (for lack of a better word). It's actually, as I understand it, largely like the Warp Drive of Star Trek and similar. The idea there is that you make a bubble of space and sit your ship inside. Then you move the section of space. Since space isn't matter or energy there's no limit to how fast such a pocket could move. Here, the space between bits of matter (like galaxies) is expanding, getting wide, and there's no limit on how fast it can do that. The interesting thing, though, is that it seems to be stretching like a rubber sheet. That is, the further away from us something is, the faster away from us it's traveling. So to get 156 light years, start 14 billion light years away and send a beam of light. Have it travel for 100 years, and it'll have moved 100 cy closer to us, but the space behind it, and therefore the space between the light and the object that created it, has expanded in the mean time and is therefore more than 100 cy. Do this for 14 billion years, add up all the expansion as we think it's happening, and you get 156 billion light years.

anon11306: If the big bang theory, and it's just a theory i might add

Me: This is ignorance of science and the word theory. The problem is that people use it the wrong way (so no fault to the poster, it's the language that is to blame). A 'theory' is not just some idea that someone came up with. It's something that people thought about, did tests to confirm, and has survived the attempts of every other scientist in the field to shoot it down. Just think about it: Einstein is world famous because he came up with his theories that describe gravity. But someone already did that. Sir Isaac Newton. Einstein's equations work better, they are more accurate (although not completely, which is why Science is currently getting into Dark Matter and Dark Energy, both of which are really weird stuff). When most people say 'I have a theory' what they mean is 'I have a hypothesis'. A guess. An idea. It takes years and years of study, debate, modification, and so on to turn a hypothesis into a Theory. Does this mean the Big Bang Theory is right? No. All it means is that, so far, no one, with thousands of people who could make their career and be famous in the scientific community for centuries, has yet been able to come up with observations or tests that show the Big Bang Theory is wrong. These next bits deal with God. My apologies to those I will insult by disagreeing with and by being an atheist.

anon8682: Why do some people refuse to believe the universe was created? Since we live in the universe we cannot even begin to explain what if anything was here prior to the start. The only logical answer is God.

Me: Well, some people refuse to believe that GOD created the universe, not that the universe was created. Current scientific thinking says the Big Bang created the universe, and that this Big Bang wasn't an intelligent being but just a consequence of the laws of its own existence. However I find your last statement to be truly insulting. Since we can't figure out what came before, and likely never will be able to, the only logical answer is God? How about this: We can never figure out what came before, so the only logical answer is that we were created by a kid in science class from a universe of which we are a sub-set? Or we were created by the Easter Bunny? There's no 'logic' there, you're just saying that your answer has to be right because science doesn't have an answer for you. Unless you are saying God is 'all those things which we as a species do not understand'. In which case God ceases to be an entity with intelligence, motives, plans, and whims and is relegated to the status of 'stuff we don't know'. A mystery to be solved and nothing more. Appeals to God of any sort are not logical. They are belief based and nothing more. I accept that God _could_ exist, but I have found no reason to suggest that he/she/it _must_ exist. And, as someone else pointed out, using 'God' as the initial cause of everything does you no good. Before the universe existed, there was God. Well... what came before God? Who created God? And if you believe God always existed, why not believe that the initial compressed dot that was the universe always existed?

anon5172: If the so called "edge" of what we conclude to be the beginning of "time" or the start of the so-called "big-bang" is only as far back as we can see due to light being way tooooo dim to see in the first place then how can anyone make an assumption as to the age in the first place? God created the heavens and the universe.

Me: The 'edge' is the 'causal edge', that is the furthest point away from us that anything could possibly be and still have some sort of effect upon the earth (such as a light in the sky). The problem with objects that far away isn't that the light is too dim. We can see them just fine (all right, we can see whole galaxies at that distance, and they show up as dots of light like stars but still). The problem is there hasn't been enough time for the light of anything further away to have reached us yet. Since no matter or energy from further than that can reach us, it doesn't much matter if it's there. It'll never affect us.


156 billion light years is just how long it took that light to get here, maybe there are stars farther out the light just hasn't gotten here yet. truthfully this is all stupid. I don't care how big it is. We will never see more than this planet because we will destroy ourselves way before we ever get far enough into space to even matter.


big bang would lead you to expect expansion in all directions Simultaneously, all particles expanding outwardly spherically. So how can the universe be flat?


I think it has to do with the 4 forces of nature (Strong Nuclear force, Weak Nuclear force, Electromagnetism and Gravity) as one in the beginning... Then somehow Gravity broke off, thus expanding the universe faster than the speed of light... Gravity holds everything together and without it the forces of nature are free to move infinity...


That's 58,106,862,400,000,000,000,000,000,000 inches.


Choosing to believe something just because the Bible says it with no other evidence is stupid.

Refusing to accept the possibility that God exists is stupid.

Balance, people. Science and religion don't have to be at either end of the spectrum.


If you consider that looking at the universe is looking into the past because of the elapsed time that occurs during the trip across space to within the distance where our telescopes can detect light, would you subtract that distance from the age of the star?


we as humans think only with a finite mind. we can't even begin to understand beyond our limited senses. of time, space, it would take man over hundred years to just get out of our solar system with a spacecraft! let alone out of our galaxy! If the big bang theory, and it's just a theory i might add. happened in the way we finite humans see it, then what a chance the universe started! there has to be more! if GOD exists, he could snap his fingers, the big bang happened, bible says And GOD said "let there be light" just a thought, mike


I think using the big bang as evidence for Genesis is absolutely pathetic.


I've seen the 156 billion light years estimate in several places - so it is probably pretty accurate. The comment about 28 billion light years being the max size the universe could be assumes c was the limit during the big bang/inflation - and that turns out to be untrue - based on current estimates, the universe expanded insanely fast during the initial bang, while all the rules of physics were being generated - perhaps 150 billion light years of expansion during that time (75 billion in every direction) - and the remaining 6 billion have occurred in the last 14 billion years - that's still allowing for galaxies to move at (3/14) c - which is pretty darn fast (40,000 miles per second!). I don't recall how fast the farthest observable galaxies are thought to travel, but those are only 12-13 billion light years away - and then some guessing goes on to estimate how fast the ones that are 78 billion light years away are moving. But please, for the love of, uh, science, stop mentioning superstitions on a fact based website like this one.


What does God answer? What created God?

What stinks about this whole debate is that, either way, we have to accept that something just 'was'. Bugs the heck out of me.


Why do some people refuse to believe the universe was created? The Bible tells us the first thing God did was create light. "let there be light, and there was" this matches exactly with the "big bang" theory. As far as the 6 day period, we do not have a way of knowing what a day meant to God. When the Bible was written no one would have had anyway to relate to what is being said now. Also we do not even know if those 6 days are complete. God is NOW. Time did not even start until creation or the big bang as it is called now. Since we live in the universe we cannot even begin to explain what if anything was here prior to the start. The only logical answer is God.


I have just logged in and am very happy to join you all folks. I am starting from zero.

I have been always thinking about the survival of light

created by big bang to travel 14 billion years without

losing its momentum and force?


the universe's size is measured in the movement of force not matter.


If you do a google search for how big universe 156 and choose the space com link there is a good article that explains why the universe is bigger than 18 billion light years.


If the so called "edge" of what we conclude to be the beginning of "time" or the start of the so-called "big-bang" is only as far back as we can see due to light being way tooooo dim to see in the first place then how can anyone make an assumption as to the age in the first place? God created the heavens and the universe.


hey i don`t get something... how can we know that the universe is big as you have said "The current, observable universe has been determined to have a width of 156 billion light years, with an error of less than 1%" when if the universe was created 14 billion years ago the farthest any matter could travel is 14 billion light years in each direction which adds to 28 billion light years across...?

so how did we get to 156 billion?

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