So if the universe is 46+ billion lightyears wide, does this go against the "big bang" theory?

Question

I've been seeing a few discussions about "How can the universe be this wide?", and I'd just like to take it a step further.

So everyone knows that the Big Bang, which started the expansion from a single point somewhere in the universe 13.7 billion years ago, was the "beginning" of the universe as we know it. So if that happened 14 billion years ago, meaning that the farthest light (including any form of radiation) has traveled since then is 14 billion light-years in any direction, how can something be 46.5 billion light-years away? Does this imply that that the Big Bang, in fact, didn't actually create all of the matter currently existing in our universe, and that there is more matter out there that hasn't come from that point of origin?

Say the Big Bang was indeed the beginning of the universe as we know it. That means the farthest our planet could possibly travel from that point is 13.7 billion light-years, meaning the farthest away anything we could possibly see is 14 billion

cont.

light years away.

I do believe scientists when they say that there is something 46.5 billion ligh-years away, it's just that how can this be if all matter has been spread from the point of the Big Bang. Obviously there's something missing here...

For those who are wondering about proof that the universe is at least 46 billion light-years wide, here's an informational video about the farthest galaxies ever discovered. http://www.youtube.com/watch?v=fgg2tpUVbXQ
Skip to around 5:05

And just to clarify, the question I have is "If the Big Bang is the center of the universe, and if everything has moved, at the very, very most, 13.7 billion light-years away, what's the explanation for there being matter that's 46.5 billion light-years away?"

Thanks for the answers so far. Keep them coming. I'm curious what other people think of this, and if anyone has any more ideas of what the answer to my question could be.

For all those who keep saying that 13.7 billion light-years is a radius and not a diameter, I know. In my original question I said "expanding 13.7 billion light-years in every direction." Every direction implies that I'm describing a radius, not a diameter. Just clearing that up :)

Answer 1

The universe is about 13.7 billion years old. Light reaching us from the earliest known galaxies has been travelling, therefore, for more than 13 billion years. So one might assume that the radius of the universe is 13.7 billion light-years and that the whole shebang is double that, or 27.4 billion light-years wide.

But the universe has been expanding ever since the beginning of time, when theorists believe it all sprang forth from an infinitely dense point in a Big Bang.

"All the distance covered by the light in the early universe gets increased by the expansion of the universe," explains Neil Cornish, an astrophysicist at Montana State University. "Think of it like compound interest."

(see link for continued article)

Answer 2

The 14-15 billion is a RADIUS not a DIAMETER

Multiple it by 2 and you get 28 to 30 billon.

Now, no one knows how thick the cosmic layer is plus there were bound to be initial particles that came out sooner then the primary mass explosion.

When an A-Bomb goes off there is an intial EMP which is radition and it comes out first, followed by the FISSION explosion. Same thing with H-Bomb Fusion explosion.

So you have a leading edge of fewer, lesser particles followed by a mass of radiation particles.

What we measure and see is the inner edge not the outer edge.

So we have to guess how big it might be and we can't exactly measure that inner edge directly so we go based on the furthest objects we can see (like Quasars).

Most of those furthest objects are seen by "lensing" processes using gravity wells. So there's a refraction potential there.

Don't be surprised to find scientists saying in 50 years we found an even further object and now the Universe is 20 billion years old.

We measure by the furtherst known object and then others add in factors as they see fit based on what is know of radation and light speeds.

As for the size it can be anywhere from 28 billion light years on up. Some estimates run 75 billion or more.

These are estimates.

Remember the big bang, while it may have only taken a second or two or three to really get moving, started putting out Gamma and other rays as it begins to lose it's density mass and gravity weakens.

Once that happens massless particles are free to move out at the speed of light.

What we can effectively measure is MASS particles.

Those things that formed Hydrogen which made stars.

The Cosmic particles can be sensed on a radio telescope.

YOu can't effectively lens them or triangulate them like you can for a body like a Quasar.

Answer 3

46.5 billion years is the estimated radius of the observable Universe. It's not based on any direst observations, because as you pointed out, we can only detect light from things within 13.7 billion years. The measurement is based on a series of computer models that use information about the Big Bang to get a sense of how it's moving and expanding.

Space craft like COBE (Cosmic Background Explorer) measure thermal fluctuations in the edges of our Universe. These give us ideas of how fast things were moving, and how they moved. The information is put in a supercomputer, and scientists make predictions about the size based on models, not necessarily observations.

The reason it can be so big, is that the boundaries of the known Universe expand faster than light. Although many people challenge this with Einstein's theories, they fail to realize the obvious fact that Natural laws only govern things with in nature. The Universe isn't really "inside" of anything we can map, model, or even make a good guess about. The Universe as an entity is a completely unpredictable being. So we do the best we can with what we have, and hope for the best. That's science at its finest.

Answer 4

There are two issues here. Age and size. The age of the universe is 13.7 billion years. The theory of size uses comoving distances. The light reaching our eyes from our Sun is from a point where our Sun was 8 minutes ago. Similarly, light reaching our eyes from a distant galaxy is also from where the galaxy was in the past not 'now' because of the continued expansion of the universe. Scientists using these comoving distance factors have thus estimated the size of the universe as it is 'now'. The cosmic microwave radiation that we see now was emitted 13.7 billion years ago and since that time has now, in the present time, condensed to galaxies which are now 46.47 billion light years away from us in distance. The size of the universe would be 92.94 billion light years in diameter. These measurements do not conflict with the Big Bang.

Answer 5

Ok two hiccups, first is that scientists have also said that at the beginning light traveled faster than light does now (that's a whole other argument), and second if the "big bang" was 13.7 billion years ago at current light speeds the universe would be 27.4 light years wide because 13.7 light years would be the radius of the blast not the diameter. 86.08 light years would be the circumference.

Answer 6

Our present day math and equipment falls to bits at a factor 1e(-40 3) seconds after the great bang adventure at t0. At that factor the singularity already exists, and is a million Planck length in diameter, unspeakably warm, and as dense as you may anticipate with the entire universe filled into such an unimaginably small quantity. The 4 forces (gravity, electromagnetism and the two nuclear forces) have been till now unified right into a single superforce, which would be Quantum Supergravity. we don't be attentive to adequate approximately this, so we gained't do any greater desirable calculations to get closer to t0. on the factor the place our present day math starts working returned, gravity separates from the different 3 unified forces. we ought to attend till the Superunified tension is defined till now we can pass deeper. precisely what occurred at t0 continues to be cloaked, so all it incredibly is obtainable are hypotheses in keeping with different springing up innovations in very freaky maths. Branes propose, case in point, that the Singularity that shaped the universe regarded while 2 branes intersected at a factor - the factor replaced into the Singularity. yet another attitude in this defined the Singularity as a digital particle. those debris come out and in of existence each and all the time interior the conventional international, and such an adventure on an extremely great scale could have shaped the universe. word that the 'you may no longer get something from no longer something' objection is already blown by potential of digital debris, and in spite of if this manner of extensive digital particle is probabilistically unlikely, such opportunities won't be a project in a pre-universe ecosystem of no-time/no-area. there is not any thank you to make those products plenty greater palatable. no person fairly is conscious yet, and there are basically an incredible style of cool innovations devoid of thank you to verify which, if any, is the only. you additionally can shoehorn God in there in case you ought to - nonetheless he's by no potential been everywhere regarded in till now. CD

Answer 7

Consider;put a mirror 1 light second away from you.
You step in front of the mirror and see your image 2 seconds later.
You have a mirror,you must send it 1 light second away from you,it travels at one half the speed of light [pretty fast} it takes 2 seconds to send it there.
Now when you step in front of the mirror,send it 2 light second away then wait for you image to return,you are going to have to wait for 3 seconds.
Well,what the heck!

Answer 8

I'm not sure, it seems pretty conflicting to me though!
The big bang theory seems pretty reasonable, but after all, it is a THEORY and theories get DISPROVEN all the time, so who knows!

Answer 9

I thought the Big Bang Theory pertained to our
Galaxy, not the Universe as a whole.

Answer 10

seems like a pretty sound argument to me. Maybe you should bring it up to an astronomy, physics, or science professor/teacher. I personally think it just goes to show how we really have no idea what is really going on.