What evidence leads you to the conclusion that nobody knows for sure? What level of rigor do you apply to the evidence that leads you to this conclusion?
Are you applying the same level of rigor to the following statement?
What evidence leads you to this conclusion?
Let me suggest an alternative: you could say:
“I don’t know, for sure. I don’t think I have enough evidence to figure out what theory is correct. But hell, for all I know, you’ve seen more evidence than I have, and therefore you might have a far better sense than I do which theory is correct, or at least which theory is more likely to be correct.”
If we we get to count all the permutations of the values of the parameters of the Big Bang model that fall within the known observational constraints, I think the Big Bang starts to win.
Sure it does. Honest 18th Century creationists, noting that the geological record refuted the obvious predictions you can make from the Biblical account (evidence of the Flood, no evidence of the old earth, only fossils of existing animals) decided that Creationism was falsified, and rejected it.
The dishonest 20th century creationists have, as a policy, that it is true no matter what. But don’t confuse their religous belief with a real creation hypothesis.
Just to quibble, the Big Bang theory was one of the ways that the observation that the galaxies were receding from each other could be explained. The Steady State hypothesis explained this also. What the Big Bang did predict was that looking in the past as we observed older and older galaxies we’d see something different, and that there should be a detectable residue from the Big Bang. That’s why the discovery of CBR was so important - it shouldn’t have been there if Steady State was right.
Maybe if you let him reply, you’ll find out. At least SlowMindThinking kindly pointed out my misunderstanding of the scientific use of the ‘theory’. So I’ll get to that now:
the·o·ry Audio pronunciation of “theory” ( P ) Pronunciation Key (th-r, thîr)
n. pl. the·o·ries
A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena.
The branch of a science or art consisting of its explanatory statements, accepted principles, and methods of analysis, as opposed to practice: a fine musician who had never studied theory.
A set of theorems that constitute a systematic view of a branch of mathematics.
Abstract reasoning; speculation: a decision based on experience rather than theory.
A belief or principle that guides action or assists comprehension or judgment: staked out the house on the theory that criminals usually return to the scene of the crime.
An assumption based on limited information or knowledge; a conjecture.
My response to Yumblie is in reference to #6 of the meaning of ‘theory’. So yeah, I messed that up. But still, is the collective popular view of scientists of the Big Bang accurate and correct?
Voyager, to the best of my knowledge the Steady State model did not predict receding galaxies. The very reason Einstein put the cosmological constant into GR was that was the only way to create a universe that was not expanding or collapsing within the framework of GR. Steady State was later modified by adding pairwise particle production as galaxies recede from each other, thus producing enough matter to create a dynamic equilibrium in the amount of visible matter. (This seems to imply an infinite source of energy, but I’ve never looked at the details.)
ParentalAdvisory, some form of the Big Bang has been the commonly accepted theory for decades. Inflation, dark energy and dark matter have been added, with different levels of acceptance and plausibility, but they are additions, not alternatives. I personally feel that GR requires some modification on cosmological scales, vice the invoking dark energy, but in the end there may be little difference. (Back in the day when I thought for a living, GR was my speciality.) In fact, the level of acceptance of the Big Bang theory is so high that I think it has caused the claims that scientists treat it as “dogma” in an attempt to convince the layman that creationism is unfairly shunted aside. (BTW, most physicists believe that some sort of quantum phenomona removes the singularity at the Bang itself. It is my thought that the Bang occurred when the three spatial dimensions we can see suddenly unraveled from a the minature scales of the other spatial dimensions required by string theory. Or that could all be hooey. It’s not like I’ve developed a mathematical model.)
Basically, the Big Bang requires only a few tenets for its occurance to have been a certainty: the laws of physics evolve in a predictable manner over time and space, a theory of gravity that at the classical level looks something like GR, and … I can’t think of anything else.
My point was that the recession of galaxies was known before the Steady State (or Big Bang) model was formulated, so you can’t really say that either predicted them - explained them yes. I’d certainly agree that the explanation from the Big Bang model was far more elegant. But you shouldn’t get brownie points when your model explains something already known. (And if it can’t it probably won’t make it close enough to a journal to be rejected. )
Hmmm, it might depend on your reading of history. The “Steady State” theory wasn’t named until well after the expansion of the galaxies was known. And, it is still being reformulated by it’s few champions, so when you went to say it came into existence is problematic.
I read history this way. Newton realized that his theory required an outside force to prevent a “big crunch”. Einstein realized that GR predicted something like a big crunch or a big bang, since there were no outside forces, unless he put in an ad hoc term, so he did. Actual, closed form analytic solutions to GR equations are few and far between even now, but eventually (1920’s) we had a Friedman universe with the Robertson-Walker metric (proven only solution for homogeneous isotropic universe in 1935) as a model of the universe. The Hubble expansion [constant] paper was published in 1929.
I would argue that at least a form of the steady state model was around before 1929, and a form of the big bang was around with the Friedman solutions (1922). So, both existed prior to Hubble’s paper. I don’t know. Maybe the steady state models are only considered to have come into existence in the 30’s with an attempt to explain galaxy recession in the context of GR and the Friedman solution, which clearly predicts a big bang like event. IIRC, the “big bangness” of the Friedman solutions was rejected because it couldn’t be, i.e., for philosophical reasons, than anything else.
There were a few proposals that can retrospectively be labelled as anticipations of the Steady State theory - for example, some different suggestions by William MacMillan, Millikan and Nernst in the 1920s and 30s. Millikan’s speculations in particular gained some wider prominence because of his extremely high public profile at the time and also had some influence in pre-war cosmic ray circles. However, it wasn’t a detailed steady-state cosmological model in the way that was to follow.
Thus the origin of the Stready State theory is usually dated to the joint papers by Bondi and Gold and by Hoyle in 1948. They did propose detailed models and also introduced the name - it’s in the title of the first Bondi and Gold paper.
Pre-Hubble models where there’s no expansion are normally referred to as static rather steady-state models.
Newton? Not Isaac Newton, surely. The universe was small back then, and definitely steady ste (though with a Biblical creation event.)
I was referring to the Hoyle model. Strictly speaking the other models could be called steady state, and they do not predict recession. However cosmology was in such a turmoil at the time, that any accurate predictions would be more luck than anything.
Yes, Isaac Newton. He realized that unless something held mass back, everything would crunch down. The only way out of it, was an infinite universe, which he knew to be an unstable solution.
I would like to premise this with the fact that I really don’t know very much about creation, evolution or the big bang so if I say something that is technically incorrect you know why.
It was interesting. I could only stay for the first 30 mintutes because I had an intramural basketball game. He seemed like a really intelligent guy, but I think his whole premise was wrong. The premise of his lecture was that evolutionist=atheist=big banger and evolutionist!=creationist. He referred to those who believe in the Big Bang as “Big Bangers.” For some reason that seemed to bother me.
I could tell that he held these beliefs as I showed up a little early and one of the first things I heard him say to the people who got their early was something along the lines of “Evolution is just a fad for atheists. They will soon find something else.” You don’t have to be an atheist to believe in evolution so I thought that was wrong right off the bat.
Now I am going from memory, but some of the things he discussed was the fact that in order for the stars to be maintaining their places and not flying out like water drops on a propeller would be because of some really strong gravity. He said there isn’t enough mass in the universe for this to be true so big bangers “made up” something called anti-matter that we can’t see to account for the other 97%.
He discredited the big bang by saying that some Dr. (Richard maybe?) Humphreys accurately predicted the magnetic field surrounding two planets. I believe Venus and Mercury. He used this to explain how Dr. Humphrey’s model was better than the big bang because it could accurately predict the magnetic field while the big bang requires people to make up numbers. He referred several times that the big bang’s number just don’t work out. I wish we could have asked questions during the lecture or stayed until after because I would have loved to ask him specifically what numbers he was talking about, but I couldn’t
Other things he mentioned was that our galaxy should be shaped like a disk if it was as old as the big bang would have you believe. Apparently after 10 rotations the galaxy should have flattened out more like a disk than the spiral it is now. Our galaxy makes a rotation once every 100k or 250k years therefore the big bang couldn’t be correct because the big bang claims that the universe is much older than this.
He also mentioned that light that reaches the end of the universe would take 4 earth days to reach the ends of our universe. Then he compared this to something that happened on the fourth day in the bible…? I can’t remember what it was now.
There was also something about the universe expanding and he laughed at the big bang’s theory for why that is happening and said that the bible says this can be explained as god pulling the universe like a set of curtains. At this point I left and went to play basketball.
Sorry if this seems kind of vague, but I am going strictly from memory.
Uh… what? I think this would be true of dark matter, but I don’t see the connection between dark matter and gravity in this comment. Space is expanding, but relatively small individual parts of it, like our solar system, are not, and gravity is the explanation.
Don’t worry about it, it sounds like pure gibberish.
I’m glad you decided to stimulate your intellect after listening to this.
That is pure gibberish. Antimatter was “made up” for completely different reasons, it does not have “antigravity”. The bit about the galaxy is also crap. I have no idea what he was talking about with the rest. Basketball sounds like a better deal.
I remember asking a similar question on this board and being told that the galaxy is fairly “flat” for exactly this reason. That’s what happens when something spins around enough times.
This is presumably the claim by Russell Humphreys that he’d successfully predicted the magnetic fields of Uranus and Neptune in this 1984 paper.
The immediate point is that, of course, the Big Bang theory is not a model of planetary formation and has never been intended to be. The very rough agreement between the prediction by Humphreys and the two observed values can be seen to support his theory, but it can’t discredit a theory that explicitly is intended to explain something else entirely and so says nothing about planets. This isn’t an either-or situation. Jackson claiming that this somehow disproves the Big Bang is a bit like saying that it also disproves that the plays of Shakespeare were written by a bloke from Stratford-upon-Avon. It’s just an unrelated issue.
There’s a more detailed examination of the prediction in this Talk.Origins page, though it’s mainly about Thomas Barnes and you’ll have to scroll down to find the section on Humphreys. Bottomline: the predictions weren’t that impressive in the first place.
Definitely not. I’m pretty sure you’re thinking of Einstein and the Cosmological Constant.
In Newton’s day there was still a vigorous debate about whether the stars were imbedded on the inner surface of a hollow “celestial sphere” that surrounded the solar system.
They didn’t even sort out that the Universe was bigger than the Milky Way until the 1920’s!
