Was the formation of our galaxy inevitable

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Discussion Overview

The discussion centers on whether the formation of our galaxy was an inevitable outcome following the Big Bang (BB) or if alternative scenarios could have emerged. Participants explore implications of pre-BB conditions, the nature of physical laws, and the potential for different cosmic outcomes, engaging in both theoretical and speculative reasoning.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Theoretical speculation

Main Points Raised

  • Some participants suggest that the laws of the universe were established at the moment of the BB, leading to the inevitability of galaxy formation, while others propose that randomness played a role.
  • One viewpoint posits that the universe undergoes a cycle of expansion and contraction, implying that each incarnation may yield different outcomes due to inherent randomness.
  • Concerns are raised about the concept of pre-BB existence and the implications of time and physical laws being undefined before the BB.
  • Some participants argue that the current understanding of cosmic expansion challenges the viability of the Big Crunch model, while others maintain that it could still be a possibility.
  • There is a discussion about the nature of acceleration in the universe, with some asserting that current evidence suggests ongoing acceleration, while others question the permanence of this trend.
  • Participants express differing views on the interpretation of cosmological data, including the role of dark energy and the implications of entropy in understanding the universe's lifecycle.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether galaxy formation was inevitable or if alternative outcomes were possible. Multiple competing views are presented regarding the nature of the universe, the Big Crunch, and the implications of current cosmological observations.

Contextual Notes

Participants highlight limitations in understanding the pre-BB state and the definitions of physical laws, as well as the unresolved nature of certain mathematical and theoretical aspects of cosmology.

wolram
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hi,was the formation of our galaxy inevitable after the BB or could there have been a different outcome, if the former is true then that implies that information or rules were stored pre BB, if the later is true what other outcome could arise.
wolram.
 
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It is generally thought that the laws of universe were created at the exact moment of the BB. They arose of random chance. But once then, galaxies were pretty much inevitable.

Of course, some other theories Eg. a certain theory involving changing values of c imply the idea that the laws of the universe change as time went on. But these are not quite accepted, at least yet.
 
The Inevitable Universe?

I believe that the Universe is a living, conscious Entity whose "life cycle" goes from one "Big Bang" through the next "Big Crunch" to the next "Big Bang" etc.

I believe that there are natural forces of this Entity that carries over from one incarnation to the next, giving rise to similar "things" but that each incarnation creates a different "experience" via the inherent factor of randomness within the Entity's system.

The Entity that is the Universe, however, can only BE the Entity that is the Universe. What else would It be?
 


Greetings !

Welcome to PF wolram !
Originally posted by wolram
hi,
was the formation of our galaxy inevitable after the BB or could there have been a different outcome, if the former is true then that implies that information or rules were stored pre BB, if the later is true what other outcome could arise.
wolram.
I'm afraid your question is somewhat problematic.
To make it slightly clearer, I could for example
ask: "I threw a coin and I got one particular side,
was it inevitable that this would happen ?"

It depends on how you view the laws of the Universe.
Are they deterministic or not. In the first case
the answer is yes and in the second case it is no.

Either way, why should it imply anything special ?
What makes this particular result special and
requiring "programming", while the other results
are all "unspacial" ?

Live long and prosper.
 
it seems that it is accepted that there had to be some sort of stored information pre BB for our universe to exist, given that energy was the precursor to the formation of our universe can anyone come up with an equation that would give the resultant effects
i live in hope thankfully yours wolram
 
Isn't there a bit of a logical problem with something existing pre the creation of time itself?

Personal theory: I would think that without a BB, the laws of physics would be undefined. Our current laws - conservation of mass/energy etc would not apply and literally any can happen, including the spontaneous uncaused appearance of the big bang.
 
There may be a way of determining which "cycle" of universe we are in, by measuring the entropy it embodies. Stephen Hawking proved that a Big Crunch does not reverse time (i. e., entropy), but laws of physics may vanish (or rearrange completely) at a singularity.

Galaxies are thought to be part of a cosmological fine-tuning at the Big Bang which requires certain initial parameters to differ by no more than one part in 1050 to obtain our current "exactly" flat macroscopic spacetime. (So a small change at the Origin might mean a tremendous change in the structure of the cosmos.) Inflationary theory attempts to address this and other anomalies of universal expansion.
 
The Pre-Time Universe?

If you can -- for one moment -- think of the Universe as a living Entity that expands from a so-called Big Bang into a very expansive Everything That Is, Has Been and Will Be...then, through natural forces, contracts (again) into a singularity which, in turn, bursts forth into a new incarnation...

...you might then see that even when Everything That Is is momentarily a singularity, it is still "only" Everything That Is.

The Universe (in my view) is an Eternal Entity of Energy whose "life cycle" is described (in brief) above.

If "Time" does exist, it exists from incarnation to incarnation of the Universe...not just in the one we're IN.
 
Hmm... Isn't the big crunch model out of favour after the red shift evidence suggesting the expansion of the universe is actually speeding up?
 
  • #10
Out of Favor?

I favor it.
 
  • #11
The Big Crunch has been quashed.
 
  • #12
Science is Transient

It'll be back.
 
  • #14
FZ+

Please don't use the word "conclusive"...and I think you know why.

Meanwhile...

Haven't OTHER "things" accellerated and then slowed down?

Haven't OTHER "things" expanded and then contracted?


...and so might the Universe...especially if there is "something" relentless and irresistable pulling it back.

I've got my ideas about what that something might be...but I have NO CONCLUSIONS.

Nor, I believe, does the Universe have a "conclusion"... not if It's the Eternal Entity of Energy -- which expands and contracts in each "lifetime" -- that I THINK it is.
 
  • #15
I suppose it's legal when I use the qualifier "seems" is it not?

Other things have accelerated and then slowed down. But other things have also accelerated and kept on accelerating... I don't think you can apply that kinda of equivalence here. All we know clearly is that the universe is accelerating right now, and there is no indication that it will stop. Hence it is probable as an idea that the universe would never come to a big crunch, until we see evidence otherwise.

The most likely scenario based on evidence we can see is that the big crunch will not happen. We may yet make another discovery yet, but that's what it looks like at present.
 
  • #16
Perpetual Notion

Actually, are you SURE that there are "things" that kept on accellerating? Name one, please.
 
  • #17


Originally posted by M. Gaspar
Actually, are you SURE that there are "things" that kept on accellerating? Name one, please.
Planets in orbit are in a constant state of acceleration. Also remember that an acceleration and a deceleration are mathematically the same thing.

M. Gaspar, you seem to have a decent picture of how you WANT the universe to be, but the evidence currently suggests otherwise. Could our theories be flawed? Certainly. But the evidence doesn't lend itself to theories that are radically different from the existing ones.

Have you read Stephen Hawkings' "A Brief History of Time"? Its a good starting point for understanding many of the concepts we are discussing here. I highly recommend it and I think you would enjoy it.
 
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  • #18
There is an outward cosmological acceleration - attributed to an Einstein-like cosmological constant or "quintessence" (themselves dependent on a "scalar field") - confirmed partially by standard-candle supernovae measurements. The scalar field (of constant, or "scalar" value over spacetime) is theorized to rest upon the energy of the omnipresent virtual vacuum. Certain supernovae, by virtue of their unique luminosity profile, provide "standard candles" for observing high-redshift accelerative deviations from the linear "Hubble law." At this time cosmologists conclude that the universe will continue to increasingly quicken beyond its current radius.
 
  • #19
Thanks for the lead...

Are you saying that the Earth is orbitting around the sun FASTER now than it did, say, a billion years ago? And how fast will it be going just before the sun blows up? Of course, AFTER the sun blows up there will be no Earth, hence, no acceleration. My point? It's always something!

Meanwhile, as was pointed out to me earlier, I have "speculations"-- not "theories" -- which seem plausable to me whether or not they fly in the face of CURRENT "evidence."

I am simply taking the case that the Universe is a living, conscious Entity and seeing how far I can get -- conversationally -- before smacking my head into the brick wall of mechanistic thinking.

Ouch. That hurt.

P.S. I will read the book to see why I am so fundamentally WRONG. But feel free to tell me in specifics, if you wish.
 
  • #20
With all due respect...

...and I mean that sincerely,

Scientists have changed their minds before. Like I said, 'Its always something" and I guess I like to believe that they will discover a something that will cause the Universe to eventually collapse.

And WHY do I "like to believe" this? Because I like to believe that the Universe is a living, conscious Eternal Entity of Energy that has infinite incarnations from "Big Bang" through "Big Crunch" to next "Big Bang".

Maybe it's not so. But if, at some point in your lifetime, "evidence" suggests to your colleagues that the Universe WILL "implode", please remember that there was someone who got there first.

Meanwhile, I believe there is a way you can "IGNORE" me.
 
  • #21


Originally posted by M. Gaspar
Are you saying that the Earth is orbitting around the sun FASTER now than it did, say, a billion years ago?

No, he's saying that gravity is an acceleration force (meters per second PER SECOND). Gravity is accelerating the Earth toward the sun, but this is counter-balanced by the Earth's tangential velocity. The result is a stable orbit.

And how fast will it be going just before the sun blows up?

aside: The sun is not going to blow up like a supernova...but it will go into a "red giant" phase.

Of course, AFTER the sun blows up there will be no Earth, hence, no acceleration. My point? It's always something!

Point taken. Energy within spacetime winds down. But what about spacetime itself? Current observation is that its expansion is accelerating and there does not seem to be anything capable of slowing it down. Maybe there is, but we don't see it yet.

Meanwhile, as was pointed out to me earlier, I have "speculations"-- not "theories" -- which seem plausable to me whether or not they fly in the face of CURRENT "evidence."

Fine. But why the contempt for current evidence?

I am simply taking the case that the Universe is a living, conscious Entity and seeing how far I can get -- conversationally -- before smacking my head into the brick wall of mechanistic thinking.

Ouch. That hurt.

P.S. I will read the book to see why I am so fundamentally WRONG. But feel free to tell me in specifics, if you wish.

No book out there will prove that the universe is not a living, conscious entity. But, by the same token, no book can prove that is true either. It's a nice idea, but what evidence is there that it's reality?
 
  • #22


Originally posted by M. Gaspar
Scientists have changed their minds before. Like I said, 'Its always something" and I guess I like to believe that they will discover a something that will cause the Universe to eventually collapse.

And WHY do I "like to believe" this? Because I like to believe that the Universe is a living, conscious Eternal Entity of Energy that has infinite incarnations from "Big Bang" through "Big Crunch" to next "Big Bang".

Maybe it's not so. But if, at some point in your lifetime, "evidence" suggests to your colleagues that the Universe WILL "implode", please remember that there was someone who got there first.

Again, ok, scientific theories can change when new evidence is obtained. Cosmology in particular is an aspect of science with a lot of uncertainty. I encourage you to study cosmology, find the evidence, and develop the explanatory model. The Big Crunch and the Cyclic Universe ideas are not off the scientific table completely at this point. We're just pointing out that the current evidence better supports a different idea (eternal expansion). The Eternal Entity of Energy idea is not part of any scientific model though (more of a religious belief).

Meanwhile, I believe there is a way you can "IGNORE" me.

As far as I can tell, this conversation is still polite. No need to take any offense. If you're not open to discussing your ideas, then don't post them.
 
  • #23
re expansion

the big crunch is i think a theory for eternalists, the thing that bothers me about continuous expansion is that it is a total loss system. the theory is that space was created by the bb, dosent that mean that a second bb cannot occuer in our pre existing space?
regards wolram.
 
  • #24


Originally posted by M. Gaspar
Scientists have changed their minds before. Like I said, 'Its always something" and I guess I like to believe that they will discover a something that will cause the Universe to eventually collapse.
Scientists don't change their mind without evidence. If they find reproducable evidence that their theory is flawed, they try to change it so that it matches all reproducable observations. They don't change their mind because something "sounds good" or because they "would like to believe".

Current evidence suggests that the universe will continue to expand indefinitely, but that is by no means a "fact" yet. There is still room for more debate and experimentation.
 
  • #25
Don't know where to begin...

I never said scientists change their minds without evidence.

I never said I don't respect scientists. In fact, I revere them.

My inviting Loren Booda to ignore me was for HER benefit, not mine. I was NOT feeling "offended" but hopelessly OUTCLASSED (as perhaps I am by MOST of you...left-brain-wise).

A "red giant" could be called an explosion in slow motion.

Noone has yet offered an example of increasing accelleration that NEVER STOPS. And, PHOBOS, it's the counter-balancing I'm "counting on" with regard to a "pulsating" Universe.

And I'll be doing some reading to shore-up or alter my views.
 

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