I have started this thread after having some tooing and froing, mingled with plenty of trolling by one of the forum's fanatical creationists, who has a habit of denying factual evidence and accepted scientific facts like Darwinism and the theory of evolution of life.
As this was being debated in the religious threads, it was rightly pointed out by James as being off topic.
Here is what I believe the BB entails and the relevant facts according to accepted mainstream cosmology today....any errors, alterations and/or modifications welcomed if needed.
Growing up in the fifties and being vaguely interested in cosmology, space etc, there were three competing theories....
The Steady State as pushed by Hoyle, Bondi, and Gold.
This was discarded after the universe was found to be expanding which effectively meant that new matter needed to be created to maintain the density as predicted by Steady State. It also predicted an ifinite universe.
The Oscillating theory: This was a theor that predicted that the universe was undergoing continious collapse and expansion cycles. This was proposed by Friedman. This was discarded because of the second law of thermodynamics, which tells us that entropy always increases within an isolated system, and never in an opposite way. Also from memory because of the fact that we never see distant galaxies blue shifted.
The Big Bang theory: This was first proposed by a Belgian Jesuit pries, Father George LaMaitre. With the serendipitous discovery of the CMBR by Penzias and Wilson, the BB theory gained in popularity, while the others fell by the wayside.
The BB has four main pillars of cosmology supporting it.
[1] The Observed expansion, which can be mentally traced backwards to a singularity.
[2]The abundance of the lighter elements.
[3] The constant relic left over heat that we know of as the Cosmic Background Radiation at 2.7K
[4] The galactic formation structure, and the very tiny variations in the CMBR where this structure took place.
Another less recognised fact is that the BB fits with our overwhelmingly supported theory of gravity called General Relativity.
The BB is often mistakenly called the beginning of the universe and an even bigger mistake of being called an explosion, which obviously conjurs up pictures of what we see as conventional explosions. It wasn't. The BB is the description of the evolution of space and time from a very hot, very dense state, at t+10-43 seconds. Before that our laws of physics and GR fail us, and a QGT is needed.
While the BB describes a beginning to the observable universe, a fact that creationists jump on to insert there "god of the gaps" to explain that beginning, the scientific facts are that as yet we do not know anything before that first Planck instant at t+10-43 seconds.
In actual fact this is a credit to cosmologists over the years that they have instead stuck with the scientific evidence no matter what the criticism.
Most probably knowing that temperatures and pressures were extreme, it is thought that conditions were such that the four known forces were all combined into what is called the superforce.
Such similar facts are verified in today's particle accelerators and colliders.
As temperatures and pressures dropped with expansion, this superforce started to decouple and created conditions called false vacuums and phase transitions, where due to excesses of energy, our very first fundamentals were created...quarks, electrons etc. At 3 minutes conditions were such that quarks started to combine forming protons and neutrons. At 380,000 years temperatures were such that electrons were able to couple with those atomic nuclei.
Another important fact that many misinterpret, is that the BB was not an explosion of matter, hurling outwards, but an expansion of the space between the galaxies.
Yet another fact that confuses people, is that we do not see that expansion over smaller scales of stellar systems, galactic systems, and even cluster of galaxies, rather it only operates over the large scale, with gravity taking effect and decoupling space expansion over the smaller scales.
People some with obvious agendas, then ask, what was before the first Plank instant? what made the BB bang? Why did it bang? The correct answer is we don't know, but again this then enables the fanatics to jump in with all manners of god/s.
But there is also educated speculation on that unknown era, some of that already described with the superforce.
While the BB is overwhelmingly accepted, it still had some nagging problems.
these were explained by a process called Inflation, of which there are variations and which I am not that familiar with.
More detailed information can be got in the following links.....
https://en.wikipedia.org/wiki/Big_Bang#Expansion_of_space
http://www.astronomy.ohio-state.edu/~thompson/1101/lecture_first_3_minutes.html
https://www.cfa.harvard.edu/~ejchaisson/cosmic_evolution/docs/fr_1/fr_1_part5.html
As this was being debated in the religious threads, it was rightly pointed out by James as being off topic.
Here is what I believe the BB entails and the relevant facts according to accepted mainstream cosmology today....any errors, alterations and/or modifications welcomed if needed.
Growing up in the fifties and being vaguely interested in cosmology, space etc, there were three competing theories....
The Steady State as pushed by Hoyle, Bondi, and Gold.
This was discarded after the universe was found to be expanding which effectively meant that new matter needed to be created to maintain the density as predicted by Steady State. It also predicted an ifinite universe.
The Oscillating theory: This was a theor that predicted that the universe was undergoing continious collapse and expansion cycles. This was proposed by Friedman. This was discarded because of the second law of thermodynamics, which tells us that entropy always increases within an isolated system, and never in an opposite way. Also from memory because of the fact that we never see distant galaxies blue shifted.
The Big Bang theory: This was first proposed by a Belgian Jesuit pries, Father George LaMaitre. With the serendipitous discovery of the CMBR by Penzias and Wilson, the BB theory gained in popularity, while the others fell by the wayside.
The BB has four main pillars of cosmology supporting it.
[1] The Observed expansion, which can be mentally traced backwards to a singularity.
[2]The abundance of the lighter elements.
[3] The constant relic left over heat that we know of as the Cosmic Background Radiation at 2.7K
[4] The galactic formation structure, and the very tiny variations in the CMBR where this structure took place.
Another less recognised fact is that the BB fits with our overwhelmingly supported theory of gravity called General Relativity.
The BB is often mistakenly called the beginning of the universe and an even bigger mistake of being called an explosion, which obviously conjurs up pictures of what we see as conventional explosions. It wasn't. The BB is the description of the evolution of space and time from a very hot, very dense state, at t+10-43 seconds. Before that our laws of physics and GR fail us, and a QGT is needed.
While the BB describes a beginning to the observable universe, a fact that creationists jump on to insert there "god of the gaps" to explain that beginning, the scientific facts are that as yet we do not know anything before that first Planck instant at t+10-43 seconds.
In actual fact this is a credit to cosmologists over the years that they have instead stuck with the scientific evidence no matter what the criticism.
Most probably knowing that temperatures and pressures were extreme, it is thought that conditions were such that the four known forces were all combined into what is called the superforce.
Such similar facts are verified in today's particle accelerators and colliders.
As temperatures and pressures dropped with expansion, this superforce started to decouple and created conditions called false vacuums and phase transitions, where due to excesses of energy, our very first fundamentals were created...quarks, electrons etc. At 3 minutes conditions were such that quarks started to combine forming protons and neutrons. At 380,000 years temperatures were such that electrons were able to couple with those atomic nuclei.
Another important fact that many misinterpret, is that the BB was not an explosion of matter, hurling outwards, but an expansion of the space between the galaxies.
Yet another fact that confuses people, is that we do not see that expansion over smaller scales of stellar systems, galactic systems, and even cluster of galaxies, rather it only operates over the large scale, with gravity taking effect and decoupling space expansion over the smaller scales.
People some with obvious agendas, then ask, what was before the first Plank instant? what made the BB bang? Why did it bang? The correct answer is we don't know, but again this then enables the fanatics to jump in with all manners of god/s.
But there is also educated speculation on that unknown era, some of that already described with the superforce.
While the BB is overwhelmingly accepted, it still had some nagging problems.
these were explained by a process called Inflation, of which there are variations and which I am not that familiar with.
More detailed information can be got in the following links.....
https://en.wikipedia.org/wiki/Big_Bang#Expansion_of_space
http://www.astronomy.ohio-state.edu/~thompson/1101/lecture_first_3_minutes.html
https://www.cfa.harvard.edu/~ejchaisson/cosmic_evolution/docs/fr_1/fr_1_part5.html