Posted on 04/24/2018 10:57:04 AM PDT by ETL
At 13.8 billion years ago, our entire observable universe was the size of a peach and had a temperature of over a trillion degrees.
That's a pretty simple, but very bold statement to make, and it's not a statement that's made lightly or easily. Indeed, even a hundred years ago, it would've sounded downright preposterous, but here we are, saying it like it's no big deal. But as with anything in science, simple statements like this are built from mountains of multiple independent lines of evidence that all point toward the same conclusion in this case, the Big Bang, our model of the history of our universe.
But, as they say, don't take my word for it. Here are five pieces of evidence for the Big Bang:
#1: The night sky is dark
Imagine for a moment that we lived in a perfectly infinite universe, both in time and space. The glittering collections of stars go on forever in every direction, and the universe simply always has been and always will be. That would mean wherever you looked in the sky just pick a random direction and stare you'd be bound to find a star out there, somewhere, at some distance. That's the inevitable result of an infinite universe.
And if that same universe has been around forever, then there's been plenty of time for light from that star, crawling through the cosmos at a relatively sluggish speed of c, to reach your eyeballs. Even the presence of any intervening dust wouldn't diminish the accumulated light from an infinity of stars spread out over an infinitely large cosmos.
Ergo, the sky should be ablaze with the combined light of a multitude of stars. Instead, it's mostly darkness. Emptiness. Void. Blackness. You know, space.
The German physicist Heinrich Olbers may not have been the first person to note this apparent paradox, but his name stuck to the idea: It's known as Olbers' paradox. The simple resolution? Either the universe is not infinite in size or it's not infinite in time. Or maybe it's neither.
#2: Quasars exist
As soon as researchers developed sensitive radio telescopes, in the 1950s and '60s, they noticed weirdly loud radio sources in the sky. Through significant astronomical sleuthing, the scientists determined that these quasi-stellar radio sources, or "quasars," were very distant but uncommonly bright, active galaxies.
What's most important for this discussion is the"very distant" part of that conclusion.
Because light takes time to travel from one place to another, we don't see stars and galaxies as they are now, but as they were thousands, millions or billions of years ago. That means that looking deeper into the universe is also looking deeper into the past. We see a lot of quasars in the distant cosmos, which means these objects were very common billions of years ago. But there are hardly any quasars in our local, up-to-date neighborhood. And theyre common enough in the far-away (that is, young) universe that we should see a lot more in our vicinity.
The simple conclusion: The universe was different in its past than it is today.
#3: It's getting bigger
We live in an expanding universe. On average, galaxies are getting farther away from all other galaxies. Sure, some small local collisions happen from leftover gravitational interactions, like how the Milky Way is going to collide with Andromeda in a few billion years. But at large scales, this simple, expansionary relationship holds true. This is what astronomer Edwin Hubble discovered in the early 20th century, soon after finding that "galaxies" were actually a thing.
In an expanding universe, the rules are simple. Every galaxy is receding from (almost) every other galaxy. Light from distant galaxies will get redshifted the wavelengths of light they're releasing will get longer, and thus redder, from the perspective of other galaxies. You might be tempted to think that this is due to the motion of individual galaxies speeding around the universe, but the math doesnt add up.
The amount of redshift for a specific galaxy is related to how far away it is. Closer galaxies will get a certain amount of redshifting. A galaxy twice as far away will get twice that redshift. Four times the distance? That's right, four times the redshift. To explain this with just galaxies zipping around, there has to be a really odd conspiracy where all the galactic citizens of the universe agree to move in this very specific pattern.
Instead, there's a far simpler explanation: The motion of galaxies is due to the stretching of space between those galaxies.
We live in a dynamic, evolving universe. It was smaller in the past and will be bigger in the future.
#4: The relic radiation
Let's play a game. Assume the universe was smaller in the past. That means it would have been both denser and hotter, right? Right all the content of the cosmos would've been bundled up in a smaller space, and higher densities mean higher temperatures.
At some point, when the universe was, say, a million times smaller than it is now, everything would have been so smashed together that it would be a plasma. In that state, electrons would be unbound from their nuclear hosts and free to swim, all of that matter bathed in intense, high-energy radiation.
But as that infant universe expanded, it would've cooled to a point where, suddenly, electrons could settle comfortably around nuclei, making the first complete atoms of hydrogen and helium. At that moment, the crazy-intense radiation would roam unhindered through the newly thin and transparent universe. And as that universe expanded, light that started out literally white-hot would've cooled, cooled, cooled to a bare few degrees above absolute zero, putting the wavelengths firmly in the microwave range.
#5: It's elemental
Push the clock back even further than the formation of the cosmic microwave background, and at some point, things are so intense, so crazy that not even protons and neutrons exist. It's just a soup of their fundamental parts, the quarks and gluons. But again, as the universe expanded and cooled from the frenetic first few minutes of its existence, the lightest nuclei, like hydrogen and helium, congealed and formed.
We have a pretty decent handle on nuclear physics nowadays, and we can use that knowledge to predict the relative amount of the lightest elements in our universe. The prediction: That congealing soup should have spawned roughly three-fourths hydrogen, one-fourth helium and a smattering of "other."
The challenge then goes to the astronomers, and what do they find? A universe composed of, roughly, three-fourths hydrogen, one-fourth helium and a smaller percentage of "other." Bingo.
There's more evidence, too, of course. But this is just the starting point for our modern Big Bang picture of the cosmos. Multiple independent lines of evidence all point to the same conclusion: Our universe is around 13.8 billion years old, and at one time, it was the size of a peach and had a temperature of over a trillion degrees.
What is a year?
If it’s expanding, what’s it expanding into? Absolute nothingness? The whole idea is horseshit.
i find much of the BB model very interesting. It could be correct. HOWEVER, 1/ the Inflation theory is not credible imho, no matter if the rest of the model might be 100 percent accurate...... and 2/ “something from nothing” is still unexplained by Science... even if God used the BB Model, the initial creation of something from nothing remains in His department (since Science can’t yet provide an alternate explanation). In short, I personally find the BBM a fascinating theory ... and if anything it helps “prove” the existence of the Creator God
My problem with the Big Bang is this: If all the matter in our universe were brought into a very small volume of space, then it would collapse in on itself and form the black hole of all black holes. Nothing can escape from a black hole, especially one so big as to contain everything. Therefore, there could not have been a Big Bang.
I saw a Unicorn ! Just can’t prove it except by story telling....
Well, there are black holes in the centers of galaxies including our own Now then, we know that matter can fall
Into black holes. But perhaps, by some mechanism yet to be elaborated, black holes are / were also sources of matter? ??
That was flat out fascinating, as difficult as it was for me to try to understand it.
OK, at time T=0, there is a big bang from a dense ball of matter.
So my question is, at time T=-1, did the matter create itself from nothing, or was the matter everlasting for an infinite amount of time before T=0?
If the matter created itself from nothing, how does big bang theory explain this instantaneous creation of matter from the empty vacuum of nothingness?
If the matter is everlasting, what suddenly caused a ball of dense matter going on for an almost infinite amount of time to suddenly explode and radiate outward?
I have never heard big bang theory address these paradoxes. I am sure they do, in incomprehensible language designed so
Scientists consider the Universe to be 14 billion years old.
Scientists believe the Universe to be 156 billion light years wide.
Assuming a relatively constant rate of travel, the outlying mass of galaxies took 14 billion years to travel 78 billion light years. So those galaxies traveled over 5 light years through space each earth year of time.
So the matter was traveling 5 times the speed of light.
And none of the big bang believing scientists see a problem with this? Really?
The BBT only addresses what happened afterwards. Other theories attempt to explain what happened prior. One such theory is called vacuum genesis. It is based on the fact that space actually is not empty, but rather filled with quantum energy and weird short lived particles that appear spontaneously out of the so-called "nothingess" of spoce.
“Vacuum genesis (zero-energy universe) is a scientific hypothesis about the Big Bang that questions whether the universe began as a single particle arising from an absolute vacuum, similar to how virtual particles come into existence and then fall back into non-existence.[1]
The concept of vacuum genesis was first proposed in 1969 during a seminar being conducted by cosmologist Dennis Sciama. Edward Tryon, in the audience, was seized by an idea and blurted “Maybe the universe is a vacuum fluctuation.”
This was treated as a joke at the time, but Tryon had not been joking. In a 1984 interview, Tryon recalled that three years later, sitting at home, he had a further revelation; “I visualized the universe erupting out of nothing as a quantum fluctuation and I realized that it was possible that it explained the critical density of the universe.”[2]
The critical density of the universe is dependent upon the rate at which the universe is still expanding. The universe is expanding at an accelerated rate, but was originally thought to be slowing down.
Furthermore, the rate at which this is changing gives the overall mass density of the universe which is denoted by the Greek letter omega. If omega is less than one, the mass density would be insufficient to stop the universe’s expansion and it would go on expanding forever.
If omega is more than one, the universe will eventually stop expanding and will thus collapse in on itself to again form another fireball not unlike the one from which it came. If omega is exactly 1, the universe’s expansion will continuously slow, but never quite halt.
Tryon’s theory requires that omega be equal to or less than one. Through calculations it has been found that omega is 1 as far as instruments are able to determine. However, the universe could be so vast that its curvature is undetectable.
The universe’s rate of expansion is accelerating and is projected to continue accelerating due to dark energy, thus omega must be lower than 1.”
https://en.m.wikipedia.org/wiki/Vacuum_genesis
Ummmmm - maybe the author didn't see the story where they pointed Hubble at an "empty" part of the sky and ended up detecting galaxies upon galaxies......
My problem with the Big Bang is this: If all the matter in our universe were brought into a very small volume of space, then it would collapse in on itself and form the black hole of all black holes. Nothing can escape from a black hole, especially one so big as to contain everything. Therefore, there could not have been a Big Bang.
It could be, I suppose, that when a big enough black hole collapses, that it turns inside out and forms a gusher of matter/energy into a different space/time. We don’t notice that happening with “ordinary” black holes in our universe. Although we can’t see them directly, we can detect their enormous masses by the effects they have on nearby matter that we can see. But maybe a big enough black hole would do the inside-out trick, and the black hole’s mass would disappear from our universe. There is no evidence for this inside-out stuff, but it does solve the problem of how we got out of the biggest of black holes.
Another speculation some have resorted to is the idea that our universe is inside a black hole, so nothing actually got out in the Big Bang.
It is a bit hard to believe that it would blow up.
It is also a bit hard to believe any reason that it would have existed in the first place.
When I was a heathen I believed it all.
How is the distance of background radiation determined?
Exactly, though some theoretical physicist can probably show you an equation that "proves" that it would blow up at a certain mass.
LOL!
Consider the growing latent energy of the expanding Universe. HINT: think stretching a rubber band.
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