Non-ballistic big bang and expansion not from a center

Cosmo Novice

This is complete rubbish and does not fit with ANY current observations. It would require mass that was not part of our Universe and I am not sure how this is "common sense"


As phinds has stated this would completely disgree with the cosmological principle of homogeneity. In fact the whole idea of "matter thats is not part of our Universe" is ridiculous. The Universe = the totality of everything, a unified spacetime in which all bosons/fermions exist and I think talking about "outside" is pointless.

pmghss

One of the points I was trying to make is that "outside" is infinite, and what we call "universe" may just be a blob of matter floating around other blobs of matter.
I am not meaning a multi-verse, in which each "universe" is separate and travel to and from each one is impossible.

Oh, and apparently I am not the only one who has these so called "rubbish" theories. Have a look at the episode of "The Universe: God and the Universe", and start around 09:50.

phinds

Which is exactly what is nonsensical, by definition. "Universe" is by definition, all there is. There IS no outside.

Uh ... dude, if you plan on learning physics from sensationalized popularizations of fanciful theories, then I can only say good luck with that.

pmghss

Then quit using the term "Universe". Call it Gobbledeegook, Blather, Blob-o-muk. Make something up. You seem to be stuck on the definition of a word. I'm calling everything we can see or detect a "Blob of Matter". Or how about - The Big Blob.

As I stated before, outside does not stop.


That episode was released weeks after my previous posts. My opinions are not based on "sensationalized popularizations of fanciful theories" as you call them. I was merely pointing out that some others in the world have similar theories. And in fact, I do not agree with some of the mainstream theories suggested on that show.

Drakkith

You're saying that everything we can see, aka the Observable Universe, is a blob of matter floating around with other blobs elsewhere? We already have a word describing your blob of matter; The Observable Universe. The Universe as a whole is defined to be everything, everywhere, no matter what. You are 100% free to imagine something else outside of the "Universe", however if you are going to post here then you are must stick to the rules of the forum which do not allow for personal theories.

Such as? The current mainstream model is based off of observations of the observable universe. They are not simply made up. Feel free to disagree, but you really don't have a good reason to other than you just don't want to believe it's true.

pmghss

Ok, then nobody should be allowed to post any theories about The Big Bang. That is exactly what it is - personal theories! There is no 100% proof of evidence the Big Bang even happened! It sounds like all you want is YOUR safe standard model theories that everyone learns in school and REPEATS it over and over again until you think it's FACT. My theories are just as valid as any of this magical-universe-was-created-from-a-single-point-of-infinite-density so-called-theory.

Everything we have witnessed in the universe "so far" has obeyed the laws of physics. And yet when it comes to the (so called beginning of the) universe itself, the realm of supernatural and fantasy seem to invade thought. Anyone can believe what they want and repeat what they have heard.
Some try to find real solutions.

To answer your question - What we see as the observable "universe" may only be because our technology can only see that far. If there are blobs of matter that are 100s of billions or even trillions of light years away, we may not be able to see them........... yet.



No, it's about conclusions taken to the extreme. The clues we have, CBR, point to "some" kind of event that happened to spread the cosmic background radiation throuout the universe. Hubble's Law points to "some" event that led to objects speeding away from one another. For some reason, these points were taken to the extreme to invent the Big Bang theory and everything starting from a dot. pfft!

phinds

The term "big bang" really has two meanings. The first is the "singularity" which is a term we use for the "start" of it all, or "t=0", and pretty much means "we don't know"

The second refers to everthing this that happened starting at one Plank Time AFTER the singularity. If you contend that that is not at all well understood and is personal therories, you will need to find another forum on which to have that discussion since that point of view will be looked at hear as what I think would be called something like low level crackpottery. It's not a bad a promoting perpetual motion, but it is not mainstream physics.


Nonsense. See above regarding the second concept.

Fuzzy Logic

He doesn't mean outside the universe, he means beyond the observable universe.

Am I wrong in saying that based on the standard model, there is no evidence to suggest there is anything different that what we already observe but BBT says nothing about what is beyond the observable universe? It's possible that there could be larger cosmological structures than galaxies, but the standard model doesn't predict them.

twofish-quant

The "standard model 2012" says nothing about whether there are universes outside of the observable universe. There are people that are working on these sorts of things, but right now its in the "we are guessing" stage.

see http://arxiv.org/abs/1107.2593 for one weird idea

Also what the "standard model" refers to, changes from year to year. In 2012, the "standard model of cosmology" is that the expansion of the universe is accelerating, which contradicts the "standard model of cosmology 1995."

If one of these weird ideas gets observations support, then they'll be part of "standard model 2025."

They do. One of the "standard model 2012" is that there are large cosmological structures, and that galaxies formed "top down". Which is to say that the largest structures in the universe were formed around the time of the BB, and that galaxies formed in these filaments. The alternative model was that there were no large structures, and galaxies formed bottom up.

The "top down model" of galaxy formation was added to the "standard model" around 1990. It wasn't part of "Standard Model '85" but was part of "Standard Model '95"

twofish-quant

There's what I consider 99.9% evidence in that we can see the big bang. Trying to argue that the big bang didn't happen to most astrophysicists is like trying to argue that the sun and moon don't exist. I see this big glowing thing in the sky, and I see the this big round thing at night.

Similarly, I see this big glowing thing in microwaves that in all directions.

There is a reason for that. If you extrapolate to t=0, then the "laws of physics" don't work, so you have to make up something weird.

We can't see them at all. If you look at 13 billion light years, you see the big bang. You can't see any further back than the big bang. We know the universe is finite in time, because we can see the end of the universe so to speak.

It's also not a technology issue. If you do galaxy counts, you'll find that the number of galaxies start going down well, well before the detection limits.

Well no.....

The current models don't say what happens at t=0. The backward guess ends at about t=10^(-52) seconds.

twofish-quant

There is a large class of speculative models called "eternal inflation" that are based on that idea. The hard part as with any speculative models is to figure out how go connect them with observational evidence, and people are pretty hard at work with that. One thing that layman don't quite realize is that there is a ton of data from observations and very little of cosmology is "pure thought."

We know from CMB measurements that the universe is isotropic and homogenous out to some limit that is larger than the directly observable universe. It's quite possible that then next round of WMAP measurements will show that there is some ultra-large scale anisotropic or inhomogenity.


It actually is. The universe is lumpy but its lumpy in the same way in all directions as far as we can tell. What people are looking for in order to figure out if we are in some even bigger bubble is evidence that the universe is lumpy in different ways in different directions.

Also a lot of the pictures you see are set up to "magnify" the lumpiness. The actual density difference between the thick parts and the thin parts of the universe is in fact extremely tiny.

People have looked and haven't found anything.

A lot of modern cosmology involves "measuring lumpiness"

http://www.astro.caltech.edu/~george...aa-powspec.pdf

One thing that people have found is that at large scales the power spectrum goes down (i.e. there aren't any hyper large walls).

There are also pretty impressive plots of the "lumpiness" of the CMB

http://backreaction.blogspot.com/200...-spectrum.html

One thing that's really impressive is that there is "extra lumpiness" at some wavelengths, and we can get them by having dark matter slosh back and forth.

Yes. They are called acoustic peaks because they result from sound waves in the early universe. Not only can you *see* the big bang, but you can *hear* the big bang. One reason that we think that there is dark matter is that it sounds different.

twofish-quant

In fact, what happens at Planck's time is extremely poorly understood and there is a ton of different ideas about what happened. The hard part isn't coming up with a new idea. The really hard part is to show that an idea is *wrong*.

Saying, I have this new idea on what happened at t=0 is not very interesting. What people are interested in is to come up with ways that you can show that a certain idea about what happened at t=0 won't work. Also there are about a dozen different proposals for what happened before the BB, and it helps to know what they are so that you don't end up reinventing the wheel.

As you move away from t=0, then things become more and more well understood. If you want to make up wild new models for what happened at Planck's time, you can do that without much trouble. Personally, I find thinking about what happened at t=300,000 years to be more interesting because you *can't* make up anything. At t=300,000, the temperature of the universe is about 3000 kelvin, and I run into things that are 3000 kelvin every day.

Mainstream physics isn't mainstream physics. Part of what makes physics interesting is that it changes surprisingly quickly. There are some basic things that I learned about cosmology in 1991 that are now known to be very wrong.

The big mistake that people make about cosmology is to assume that it's philosophy, when in fact it's quite observational. We know about the coast of Norway because we can map the coast of Norway, and we know about the big bang because we can see and map it.

Chronos

I agree with TQ, our observational data is very extensive and sophisticated. Scientists work very hard to eliminate systematic [measurement] errors, so, our data is highly reliable and well vetted. The interpretation of that data is a different matter. Despite the best efforts of the best scientists representing a number of specialties [math, particle physics, cosmology, etc.] it is still difficult to reach a consensus on what the data is telling us. We build and tear down different models on a daily basis. The one we have now [LCDM] is very strong, but, still imperfect. There is no disagreement on that point. That's why we continue to explore, measure, calculate and imagine.

Drakkith

No, the standard model for cosmology, which is the Big Bang model, is not a "personal" theory. It has been developed by thousands of people all over the world from the best observations we are capable of making with the most advanced equipment ever built by mankind for this task. It is anything but a "personal theory".

There isn't 100% proof that I even exist. If you are looking for 100% proof of anything, then science is not for you. I suggest you read up on PF rules about the purpose of this site. It may surprise you that the main purpose is to teach people about mainstream science, not banter back and forth about personal theories.

We don't know about the beginning. It isn't even possible at the moment. It may not ever be possible. We can only extrapolate backwards using our current knowledge, which is almost guaranteed to be incorrect at the energy levels of the very early universe.

The limit on how far we can see is NOT based on our technology, it is based on the finite speed of light. No amount of technology is going to overcome that unless it turns out that we could somehow work around the speed of light being the maximum speed limit. And that falls into the realm of science fiction, not science.

You have some misconceptions about this subject. The Big Bang theory says almost exactly what you just said. It does NOT say that the universe started from a singularity.

nihilnemo

Anyone here ever read Flatland by Edwin Abbott? Beings of a 2 dimensional reality could not comprehend a 3 dimentional visitor. Hmmmm, wonder what we don't comprehend?

chaszz

Sorry, but for one thing, I don't even comprehend these 2 dimensional beings or their 2 dimensional world. Even if they are only one atom thick these beings are in the third dimension. If not, how do they live, eat, grow, excrete, reproduce, die, think about the third dimension, or anything? They are just as inconceivable to me as the five, six or eleven dimensional places I also cannot comprehend.

DaveC426913

No, they are not one atom thick. They have zero thickness.


Not quite. We can understand lower dimensions. I can easily comprehend manipulating lower-dimensional objects, such as taking a 0D point and sweeping it one inch to create a 1D line, then sweeping the line one inch to create a 2D square then sweeping the square one inch to create a 3D cube.

But it becomes challenging to comprehend sweeping a cube one inch to create a 4D tesseract...