The only answer to Why that does not precipitate an infinite regress and, in effect, begs the question is There Is No Why. Rather: How did the BB come about?' 'Planck era' spontaneous symmetry breaking.

Nothing is unstable. — Frank Wilczek

People in Olden Times, that being before about last week, generally believed that the Universe was animated by reason. Philosophers even went so far as to think that discerning this reason was an important part of what they did. They weren’t smart enough to know that they’re really just robotic machines whose only role is to propagate. So get over it.

Something like the conditions of the universe are such that, given a specific set of circumstances, phenomenon X happens.

For me, the only way to avoid an infinite regress into "why" questions as to causal beginnings is to think that the universe is eternal: we live in a universe of universes, which has always been and always will be, in some manner.

IF this is true, then we can't ask why anymore. If it's false, the question you raise stands. I've heard it said more than a few times that nature is essentially active, thus there is something about activity which is less taxing than nothingness.

... the universe is eternal: we live in a universe of universes, which has always been and always will be, in some manner. — Manuel

Well, I'll drink to that! :up:

Is there any hard proof that there was a Big Bang in the first place?

And if there was one, how come no one heard it? :wink:

The Wikipedia entry on Georges Lemaître is a mine of insights on this question.

I sometimes draw attention to this paragraph [comments by me]

By 1951, Pope Pius XII declared that Lemaître's theory [of the "big bang"] provided a scientific validation for Catholicism [presumably 'creation ex nihilo']. However, Lemaître objected to the Pope's declaration, stating that the theory was neutral and there was neither a connection nor a contradiction between religion and his theory. Lemaître and Daniel O'Connell, the Pope's scientific advisor, persuaded the Pope not to mention Creationism publicly, and to stop making proclamations about cosmology. Lemaître was a devout Catholic [actually a priest], but opposed mixing science with religion, although he held that the two fields were not in conflict.

-----

For me, the only way to avoid an infinite regress into "why" questions as to causal beginnings is to think that the universe is eternal: we live in a universe of universes, which has always been and always will be, in some manner. — Manuel

I'm interested in Roger Penrose's conformal cyclic cosmology model, though I can't claim to understand the details of his argument for it.

Is there any hard proof that there was a Big Bang in the first place?

No, or at least I don't know of any proof, its just that some people believe that's how the universe got started.

And if there was one, how come no one heard it? :wink:

Apparently because humanity hadn't come into existence yet, and so therefore nobody was around to hear it, according to those who believe in the Big Bang.

And besides space is a vacuum so you can't hear anything.

And besides space is a vacuum so you can't hear anything. — HardWorker

Interesting. So, if no evidence and no witnesses, then perhaps it never happened?

John Hand's, in his magisterial and quite contrarian book, Cosmosapiens, explains all candidates for the origins of the universe, which includes Penrose's. Hand's book is a for the serious layperson, not so much as say a book made by Tyson, which would be more for everybody.

Hands essentially points to issues with all models, including, what he calls, "the Hot Big Bang" model. I believe he mentions that the cyclical universe gets around the big bang issue, but it doesn't address why the universeS are built in this manner.

We won't find out, I don't think. But evidence now confirms only one universe.

Cheers.

Well even if that is the case, that still leaves the question of why there was a Big Bang in the first place. — HardWorker

If God created the big bang, you'd still be left with the question of why. You'd also be left with that question if he didn't.

Interesting. So, if no evidence and no witnesses, then perhaps it never happened?

Maybe not. Who knows? Its just a theory.

Thanks - John Hand seems another very interesting author. I recently discovered another interesting popular science author, Timothy Ferris, who covers similar territory.

(So many books, so little time!)

Call me romantic, but I think there’s a reason for it all. Not that one individual might ever know it, but we have a part to play.

I'll keep a note then. Hands' book is by far the best science book I've read, by far. But, as you say, too many books, too mucho info.

Call me romantic, but I think there’s a reason for it all. Not that one individual might ever know it, but we have a part to play. — Wayfarer

Hmm. Reason as in it happened because of X or Y, yes. Reason in some deeper sense is more problematic. We are the only creatures (so far) in the known universe to have reasons or knowledge. Quite baffling to have learned this much in the 20th century.

Through sheer dumb luck, of course.

Is there any hard proof that there was a Big Bang in the first place? — Apollodorus

Too hard, perhaps. There is indeed evidence. Does it amount to proof? That'll be down to you.

Oddly, those who need no evidence to be convinced that god created the world seek evidence here.

YOU could call them the worst birthday presents ever. At the meeting of minds convened last week to honour Stephen Hawking’s 70th birthday – loftily titled “State of the Universe” – two bold proposals posed serious threats to our existing understanding of the cosmos.

One shows that a problematic object called a naked singularity is a lot more likely to exist than previously assumed (see “Naked black-hole hearts live in the fifth dimension“). The other suggests that the universe is not eternal, resurrecting the thorny question of how to kick-start the cosmos without the hand of a supernatural creator.

While many of us may be OK with the idea of the big bang simply starting everything, physicists, including Hawking, tend to shy away from cosmic genesis. “A point of creation would be a place where science broke down. One would have to appeal to religion and the hand of God,” Hawking told the meeting, at the University of Cambridge, in a pre-recorded speech.

:scream:

Read more: https://www.newscientist.com/article/mg21328474-400-why-physicists-cant-avoid-a-creation-event/#ixzz749vWdJlV

So, there are some kinds of theories that will be resisted because they seem to imply divine creation. I think that says something interesting.

Oddly, those who need no evidence to be convinced that god created the world seek evidence here. — Banno

Actually, my position is that we should have some evidence before we take anything for fact.

However, according to @HardWorker, Big Bang is just a belief:

its just that some people believe that's how the universe got started. — HardWorker

Plus, if no one heard it and there was no sound, then it wasn't a "bang".

Unless Hoyle meant something else ....

Actually, my position is that we should have some evidence before we take anything for fact. — Apollodorus

There is voluminous evidence, but if you’d rather believe some anon poster on an internet forum then that probably won’t make any difference.

Isn't big bang a scientific religion?

There is voluminous evidence, but if you’d rather believe some anon poster on an internet forum then that probably won’t make any difference. — Wayfarer

Well, we all are anon posters on an internet forum. And I didn't say I believe anyone.

But @HardWorker may have a point in that it does involve a degree of belief. Most of us have no access to that voluminous evidence, or no time or inclination to examine it.

So, arguably, we accept the theory on faith and trust.

To learn how wrong you are, read up.

To learn how wrong you are, read up. — Wayfarer

Perhaps Corvius has it on faith that there was no big bang.

So, arguably, we accept the theory on faith and trust. — Apollodorus

It's a gross equivocation of the meaning of both. I have faith and trust in science, insofar as I accept that it is conducted by people of integrity who have both the education and access to the resources to investigate and validate these kinds of theories. I presume that, if I undertook the same training and viewed the same research, then I would probably arrive at the same conclusion. But this is not really comparable to religious faith or trust. Please read up to that paragraph I quoted about Georges LeMaitre, who first discovered the 'big bang' theory. He was a Catholic priest, who nevertheless, as a scientist, admonished the Pope not to appeal to science to validate religion. I think that is a really profound lesson. I'd like to think that if M. LeMaitre were able to drop in on this thread, that he would not read things that would insult either his science or his faith.

To learn how wrong you are, read up. — Wayfarer

If there were bing bang to create the size of the universe, then the explosion would have created immense amount of debris and dusts, which would still be floating around in your room, so you wouldn't be able to read your screen or type any texts for sure :D

If there were bing bang to create the size of the universe, then the explosion would have created immense amount of debris and dusts, — Corvus

Yeah sure Corvus, because you think that, then it undoubtedly must be so. No doubt you're an expert in all this kind of thing.

Yeah sure Corvus, because you think that, then it undoubtedly must be so. No doubt you're an expert in all this kind of thing. — Wayfarer

It is just a simple common sense WF. You don't need to consult an expert for that, I would imagine :D

I think you under estimated how large the universe is, and the power of explosion to create it, if it ever happened, I shudder to think. :chin:
I am quite certain that it wouldn't had been a bouncy castle pumping up affair for sure, if it really ever happened.

Sure. All those guys who built the Hubble are just blowing smoke. Losers.

no evidence — Apollodorus

Observation achieved with the help of complex calculation and inference is evidence. I assume ongoing evaluation of method.



Belief and trust are ordinary qualities we engage to what degree we like, all the time. Science doesn't reify. It gives us jigsaw pieces. Being finite ourselves we don't and shan't see everything.

no sound, then it wasn't a "bang" — Apollodorus

We don't know how long time is, and we don't know how much (things) "nothing" has got in it. By analogy, if we are on what might "look" like an upswing on an existence wave . . . The "big gentle lapping"?

Some people, have had a glimmer of person, and time, and light, appearing in "rapid succession" (perhaps they turned a "corner" into "sight" in our "model"). A tenable enough variant view is that "person" appeared later, with human folk.

(Light has a noticeably specific measurement.)

What scientists have always been doing is tuning in natural ears / eyes and instruments. Diagrams in books and "music of the spheres" (intuited rationally as well as remembered or even misremembered from previous investigators) are expressions of findings from all methods.

We don't know how much before before, before before was.

All "why" questions are partly "how" questions. All "how" questions are partly "what" questions. The universe is analogies, all the way down (one of my mottoes :wink: ).