ilovephysics.com :: free online physics help, tutorials, forums, classes, misconceptions in / Primordial Density Perturbations at Stellar Scales

jaypee · 2007-07-15 09:26:57

I need some help with two questions. In the standard paradigm, the formation and evolution of structure in the Universe originates in the scale-invariant quantum fluctuations that grow by gravitational amplification following cosmic inflation to produce all structure we observe today. This leads to a heirarchal bottom-up feature, i.e. smaller bodies merge to form larger bodies. The distribution of galaxies and clusters of galaxies (SDSS) are correlated to the power spectrum of these primordial pertrubations. However, structure formation arguably starts at much smaller scales, i.e at the stellar level with stars forming (with planets around them), and then organizing into galaxies. First question is: Can the primordial density perturbations survive in protoplanetary disks and perhaps influence the formation of planetary systems ?
2nd Question: Can the contraction of a molecular gas cloud preserve these residual primordial perturbations left over in the pristine gas following the Dark Ages? (if yes, can the same be preserved in an enriched (Pop I) gas cloud ?). Thanks.

Last edited by jaypee (2007-07-15 09:28:40)

steve · 2007-09-20 06:12:18

I do not have an immediate answer for you untill I find out from you your general idea of what was before the Big Bang.

Steve

jaypee · 2007-09-20 06:19:14

Not quite sure how is that relevant to my question. I am mainly interested in knowing whether the primordial density perturbations (CDM or baryonic) might influence stellar clouds protoplanetayr discs and the emerging panetary systems. From numerical simulations, we know that CDM subgalactic haloes could survive to teh present time, is it possible then that they might shape up stellar systems and how?

steve · 2007-09-21 05:24:01

You have asked quite a question, In simple terms, what do you want to know? What is it that you are trying to figure out?

Steve

jaypee · 2007-09-23 07:28:45

The question is simple: Can the primordial density perturbations survive until the present time as subgalactic haloes and influence the formation of planetary systems?

steve · 2007-09-23 09:59:37

What difference would it make? What is a yes or no answer going to do for you? After all my answer would just be my opinion, and not a fact. I am curious why you would care to know about this. I can guess from your question that you believe that the universe started with a bang. Right?

Steve

jaypee · 2007-09-23 10:01:24

yes. right

steve · 2007-09-23 21:50:57

With regards to the big bang, are you not curious about how this singularity, this primeval atom came into being? It is said that the Big Bang created matter,energy, space, and time. If none of this existed before the bang, then what was this thing that blew up made of? Where was it existing or floating if there was no space? Don't you think that it was existing for some time before it "decided" to explode? Maybe you are a religious person, and God created the Big Bang. All of science is concerned with what happened after the Big Bang, but no real concern for how or what really happened. Maybe man is happy with this answer and does not really want to tear apart his safe cozy theory. Too many unanswered questions regarding this "magical" occurance to take it seriously.

Steve

jaypee · 2007-09-24 06:15:35

Your questions are truly valuable. But science progress n small steps. The first step is to understand thw big bang itself and what happenend after, cause we have access to observations that can prove and disprove this theory. Once we know how it happened, we can then ask what was before it.

steve · 2007-09-29 04:18:33

Don’t you find it odd that science says that there was a bang but cannot say for certain what went bang, or how it happened. Don’t you think that they are trying to reverse engineer the creation of the universe by going back in time until they reach the answer.

Problem is that they are ignoring the fact that the universe cannot just appear out of nothing. They just want to overlook this huge mystery, it gets in the way of their theory. Seems like they do not want anything to question their authority.

How are we going to find out how it happened when the cosmologist are only concerned about the after effects of this supernatural bang. If you look for the information on what happened before or how it happened you will find many answers that say we don’t know or this atom out of nowhere exploded. They tell us that it definitely happened, but we have no idea how, science just can not explain it. Really, how convenient. Lets just ignore this creation of the big bang, and watch all the debris moving through space and say that proves the big bang is the only logical theory.

Steve

jaypee · 2007-09-30 06:38:46

Well, the only other alternative is that the Universe existed ever since forever. or teh steady state theory but evidence is against it. But how can we explain the expansion other than an explosion? how can u explain the CMB radiation? The evidence supporting the big bang are tremendous. The question of what was before it, cannot be answered now but I am sure we will find it one day.

steve · 2007-09-30 09:59:58

Nobody was around to witness the big bang, so we just assume that from what we can observe, that something must have exploded or expanded to cause all of this. A lot of something out of nothing. Matter and energy just seemed to come from nowhere. The problem is that these “experts” say that there was no time or space before the big bang. This means that not only did something appear out of nowhere and then explode, but this thing had to exist in space for a time before it worked its magic creation of the universe. Sure it all makes sense except what caused it, where this thing came from, and why it decided to explode all by itself. It sounds more like this type of “supernatural thinking” belongs in a religious book. There is just too much missing data to make a stable foundation for this theory. We may not know what the right answers are, but we can spot incorrect, or inconsistent answers. The first step in finding the truth is to weed out all of the data that does not fit, or goes against reason. We use logic and reason to get us to the idea of the big bang. We can time the occurrence of the big bang down to less than a second yet cannot explain what happened right before that. The “experts” will tell you that the laws of physics break down right before the bang, so they cannot explain it. How convenient. Don’t you think that what they mean is their theory breaks down at this point. If the theory doesn’t work, fine stop trying to make a square peg fit in a round hole. Look, the universe is here for all to see and there is a logical explanation for it all. We will never find the answers if we refuse to let go of unworkable theories. Sure there might have been some explosion, but it might have nothing to do with how the universe was created.

Steve

Announcement

#1 2007-07-15 09:26:57

Primordial Density Perturbations at Stellar Scales

#2 2007-09-20 06:12:18

Re: Primordial Density Perturbations at Stellar Scales

#3 2007-09-20 06:19:14

Re: Primordial Density Perturbations at Stellar Scales

#4 2007-09-21 05:24:01

Re: Primordial Density Perturbations at Stellar Scales

#5 2007-09-23 07:28:45

Re: Primordial Density Perturbations at Stellar Scales

#6 2007-09-23 09:59:37

Re: Primordial Density Perturbations at Stellar Scales

#7 2007-09-23 10:01:24

Re: Primordial Density Perturbations at Stellar Scales

#8 2007-09-23 21:50:57

Re: Primordial Density Perturbations at Stellar Scales

#9 2007-09-24 06:15:35

Re: Primordial Density Perturbations at Stellar Scales

#10 2007-09-29 04:18:33

Re: Primordial Density Perturbations at Stellar Scales

#11 2007-09-30 06:38:46

Re: Primordial Density Perturbations at Stellar Scales

#12 2007-09-30 09:59:58

Re: Primordial Density Perturbations at Stellar Scales

Board footer