Holes in Big Bang

[DeiRenDopa]

I think most readers will have some familiarity with the CMB (cosmic microwave background), WMAP (Wilkinson Microwave Anisotropy Probe), SN (or SNe, supernovae), but perhaps considerably less familiarity with BAO (Baryon Acoustic Oscillations).

If you've done a year or so of physics and/or math at university (YMMV), you may find this concise overview of BAO both interesting and helpful.

 

[Badly Shaved Monkey]

Incidentally I think the indicated position for the cold spot is about 180 degrees out in galactic latitude. The cold spot is on the bottom right - it's that blue/black region.

I am glad someone has said that. I thought I was just being stupid.

 

[DeiRenDopa]

The universe that can be seen is smaller thna the universe that possibly exists?

The determination of the age of the universe is made rather accurately, the Hubble constant gets narrowed every year. But it is based upon the Hubble constant.

This is kind of interesting:
http://hubblesite.org/newscenter/archive/releases/2009/08/

The "Related Links" part of that page has a link "Science Paper By: A. Riess et al. (PDF document)"; however, when I clicked on it I got gibberish.

Here is arXiv abstract version of that paper.

In a nutshell, Riess et al. embarked on a programme to reduce the estimated uncertainty in an estimate of H₀ from ~11%, obtained in the Hubble Key Project (Freedman et al. 2001), to <5%. The paper reports the results, and success; the key to success may be summarised as reducing the uncertainties in the four largest sources of systematic error identified by Freedman et al.

 

[Michael Mozina]

Good thing, then, that no results in cosmology depend on B), nor is B) a prediction or claim of the theory.

But we've discussed that more times than I can recall and it hasn't stopped you from posting exactly the same thing again and again, so I'm not going to bother.

I fail to understand why you believe that I am somehow obligated to agree with you only because we've discussed the idea before. The fact of the matter is that none of us have any idea how compact the universe may have been at some point in the distant past.

 

[Perpetual Student]

A Gyr? Such a large change in the estimated age, derived from cosmological models, would seem unlikely; naively, that'd be ~8 sigma, which is as close to "impossible" as never mind.

I can only answer the above by saying the obvious:
We don't know what we don't know. That's why estimates of the age of the universe have been modified again and again over the years. Stay tuned!

 

[Zeuzzz]

I can only answer the above by saying the obvious:
We don't know what we don't know. That's why estimates of the age of the universe have been modified again and again over the years. Stay tuned!

Precisely. Period.

 

[sol invictus]

I fail to understand why you believe that I am somehow obligated to agree with you only because we've discussed the idea before.

Well, some people learn from having something explained to them. Pardon me for thinking that you might be one of them.

You made an assertion "Of course that particular measurement is based upon two primary assumptions:...
B) Everything (all matter and energy) was once condensed to a point" which is false (for multiple reasons, actually). Of course you've failed to back up that assertion (because it's false), and to make matters worse you ought to know it's false (because we've discussed it sickeningly many times already).

Does that sound like intellectually honest behavior, Michael?

I can only answer the above by saying the obvious:
We don't know what we don't know. That's why estimates of the age of the universe have been modified again and again over the years. Stay tuned!

That's not the issue. Sure, the age was revised many times as the data improved, as is the case with just about every quantity in the history of science. The question, though, is whether it was ever revised to something that fell significantly outside the error bars of the previous estimate, say by 4 sigma (let alone 8!).

I doubt it, but I don't know for sure - perhaps DRD can comment.

 

[Perpetual Student]

That's not the issue. Sure, the age was revised many times as the data improved, as is the case with just about every quantity in the history of science. The question, though, is whether it was ever revised to something that fell significantly outside the error bars of the previous estimate, say by 4 sigma (let alone 8!).

I doubt it, but I don't know for sure - perhaps DRD can comment.

It was not that many years ago that the number 20 billion years was thrown around.

 

[Perpetual Student]

It was not that many years ago that the number 20 billion years was thrown around.

Some years later it was 15 to 20 billion years.

 

[Michael Mozina]

Well, some people learn from having something explained to them. Pardon me for thinking that you might be one of them.

Pardon me for not agreeing with you "just because".

You made an assertion "Of course that particular measurement is based upon two primary assumptions:...
B) Everything (all matter and energy) was once condensed to a point" which is false (for multiple reasons, actually). Of course you've failed to back up that assertion (because it's false), and to make matters worse you ought to know it's false (because we've discussed it sickeningly many times already).

Um you seem to be under the illusion that A) you speak for everyone on this topic (your beliefs are all that matter) and B) I'm obligated to agree with you only because we've discussed it before. Neither assumption is true.

Does that sound like intellectually honest behavior, Michael?

What is not 'intellectually honest behavior" is your belief that your statements are "gospel" and no one is allowed to disagree with you once you have spoken with them about it.

That's not the issue. Sure, the age was revised many times as the data improved,

But somehow you've convinced yourself that won't happen again in the future?

 

[Michael Mozina]

http://en.wikipedia.org/wiki/Big_Bang

In 1931 Lemaître went further and suggested that the evident expansion in forward time required that the universe contracted backwards in time, and would continue to do so until it could contract no further, bringing all the mass of the universe into a single point, a "primeval atom", at a point in time before which time and space did not exist. As such, at this point, the fabric of time and space had not yet come into existence.[13]

Timeline of the Big Bang
See also: Timeline of the Big Bang
Extrapolation of the expansion of the universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past.[26] This singularity signals the breakdown of general relativity. How closely we can extrapolate towards the singularity is debated—certainly not earlier than the Planck epoch.

Whom shall I believe sol, you or Wiki?

 

[Michael Mozina]

http://en.wikipedia.org/wiki/Planck_epoch

Theoretical ideas

As there presently exists no widely accepted framework for how to combine quantum mechanics with relativistic gravity, science is not currently able to make predictions about events occurring over intervals shorter than the Planck time or distances shorter than one Planck length, the distance light travels in one Planck time—about 1.616 × 10-35 meters.

http://en.wikipedia.org/wiki/Planck_length

In physics, the Planck length, denoted \scriptstyle\ell_P \ , is a unit of length, equal to 1.616252(81)×10−35 meters. It is a base unit in the system of Planck units.

Sure sounds like a "point" from where I sit. Would the term "smaller than a breadbox" be more to your personal liking?

 

[Reality Check]

Some years later it was 15 to 20 billion years.

Some years later than that it was 16 to 19 billion years.
Some years later is was ~14 billion years.
Currently it is ~13.7 billion years.
I am not aware of what your point is. This is how all measurements in science are refined as new data is collected.

 

[sol invictus]

It was not that many years ago that the number 20 billion years was thrown around.

Some years later it was 15 to 20 billion years.

Question: do you know what an "error bar" is?

What is not 'intellectually honest behavior" is your belief that your statements are "gospel" and no one is allowed to disagree with you once you have spoken with them about it.

My statements about what the theory is and whether that assumption was necessary for that measurement were absolutely correct. Yours were wrong, as your own references below confirm. That's the same thing that happened last time - you were wrong, I was right, and all the references confirmed that. But you then went ahead and repeated the same intellectually dishonest statements.

http://en.wikipedia.org/wiki/Big_Bang

What Lemaître suggested in 1931 is now magically a "primary assumption" on which a contemporary measurement was "based"? On what planet do you spend most of your time, Michael?

Whom shall I believe sol, you or Wiki?

Since wiki agrees with me and disagrees with you, it doesn't matter. "How closely we can extrapolate towards the singularity is debated—certainly not earlier than the Planck epoch. "
And yet you said "Everything (all matter and energy) was once condensed to a point." That's dead wrong, Michael.

http://en.wikipedia.org/wiki/Planck_epoch

http://en.wikipedia.org/wiki/Planck_length

Sure sounds like a "point" from where I sit.

A length sounds like a point to you, Michael? Really?

Would the term "smaller than a breadbox" be more to your personal liking?

You tell me just what it is you think was smaller than a breadbox, and I'll answer that. If you respond "the volume of the universe", then your statement will be just as wrong.

 

[sol invictus]

But somehow you've convinced yourself that won't happen again in the future?

Did I say anything like that, Michael? Did I even imply it? No I didn't, did I? So why did you ask? Is that an intellectually honest tactic?

Question for you or PS: what does this http://www.ucolick.org/~bolte/papers/BolteHogan1995.pdf article tell you about the question I asked earlier ("The question, though, is whether it was ever revised to something that fell significantly outside the error bars of the previous estimate, say by 4 sigma (let alone 8!).")? http://www.ucolick.org/~bolte/papers/BolteHogan1995.pdf

 

[DeiRenDopa]

I can only answer the above by saying the obvious:
We don't know what we don't know. That's why estimates of the age of the universe have been modified again and again over the years. Stay tuned!

At one extreme, we cannot know the age of the universe ... unless and until there is a totally satisfactory solution to the problem of induction (there is no guarrantee that the implicit or explicit solution employed in science, or part of it, will be satisfactory to you, even only once).

At the other extreme, the estimated age of the universe IS 13.69 +/- 0.13 and 13.72 +/- 0.12 Gyr (it's a particular estimate, arrived at using a method described in the paper in which it is published).

In my earlier post, I wrote about what the stated estimates of uncertainty mean, and how the age estimate itself is model-dependent (change the values of the parameters in the model, and the estimate will change; change the model itself, and you will have a different estimate).

Your post (which I'm quoting) seems to be about something in between; still science-based, but beyond even classes of models (and methods).

It's an interesting space! I'd like to explore it more, but I don't think this thread is the place to do so, and in any case, I doubt I'll have enough time and opportunity to do justice to it today (i.e. stay tuned!).

 

[DeiRenDopa]

It was not that many years ago that the number 20 billion years was thrown around.

Some years later it was 15 to 20 billion years.

I wonder if someone has collected the various estimates and written them up, much like Huchra has done for the Hubble constant?

I recall, vaguely, that there were some interesting results a decade or three ago, concerning the estimated ages of various globular clusters (GCs); IIRC, the estimates were based on various models of stellar evolution, and CMDs (colour-magnitude diagrams), which summarise hundreds (or thousands) of individual observations. The GCs, or some of them, had estimated ages greater than the (then) estimated age of the universe¹!

Might this be what you are referring to?

¹ No prize for guessing how this apparent inconsistency is, or was, resolved ...

 

[Michael Mozina]

My statements about what the theory is and whether that assumption was necessary for that measurement were absolutely correct.

Oh for crying out loud. No "assumption" is "necessary" evidently, and none of you even agree on what is necessary. DRD doesn't even seem to think inflation theory is "necessary", but that is in fact the present "dogma". The notion that everything was collected together into one physically connected 'thing' (whatever you want to call it) is not something you could ever hope to demonstrate. It's an "act of blind faith". Period.

Yours were wrong, as your own references below confirm. That's the same thing that happened last time - you were wrong, I was right, and all the references confirmed that. But you then went ahead and repeated the same intellectually dishonest statements.

Baloney. You just went off on the word "point".

What Lemaître suggested in 1931 is now magically a "primary assumption" on which a contemporary measurement was "based"? On what planet do you spend most of your time, Michael?

It's still listed on Wiki as part of the 'dogma' sol. Why is that?

Since wiki agrees with me and disagrees with you, it doesn't matter. "How closely we can extrapolate towards the singularity is debated—certainly not earlier than the Planck epoch. "
And yet you said "Everything (all matter and energy) was once condensed to a point." That's dead wrong, Michael.

Does "singular mass body smaller than an atom" work for you?

A length sounds like a point to you, Michael? Really?

It really sounds to me like you're attempting to avoid the *POINT* of my statement and fixate on trivia.

You tell me just what it is you think was smaller than a breadbox, and I'll answer that. If you respond "the volume of the universe", then your statement will be just as wrong.

It seems to me that you aren't even going to deal with the point of my statements, you are intent on fixating on unimportant trivia (the term 'point') and you're engaging in hair splitting (atom size splitting as it were).

The point of my statement is that there is no way we can be sure how far back we can "wind the clock". There is no way to know that all mass and energy were collected together to anything smaller than say 5-10 percent of it's current size. There is no way to know that is was smaller than a breadbox, smaller than atom, or anywhere even *REMOTELY* close to a planks length. You go right ahead though and ignore the point entirely and smugly pat yourself on the back for fixating on trivia and avoiding the point of my post, but is that really "intellectually honest' of you sol?

 

[Michael Mozina]

Some years later than that it was 16 to 19 billion years.
Some years later is was ~14 billion years.
Currently it is ~13.7 billion years.
I am not aware of what your point is. This is how all measurements in science are refined as new data is collected.

So what makes you think new data won't radically alter than number again?

 

[sol invictus]

No "assumption" is "necessary" evidently, and none of you even agree on what is necessary.

So you admit you were wrong when you asserted "Of course that particular measurement is based upon two primary assumptions"?

Baloney. You just went off on the word "point".

Pardon me for taking your words seriously.

It's still listed on Wiki as part of the 'dogma' sol. Why is that?

Evidence? It's not in the part you quoted.

Does "singular mass body smaller than an atom" work for you?

Nope. What precisely is smaller? Do you mean, "the volume of the universe was smaller than the volume of an atom"? If so, that's just as wrong.

The point of my statement is that there is no way we can be sure how far back we can "wind the clock". There is no way to know that all mass and energy were collected together to anything smaller than say 5-10 percent of it's current size.

How did you arrive at the figure of 5-10%?

There is no way to know that is was smaller than a breadbox, smaller than atom, or anywhere even *REMOTELY* close to a planks length.

What was smaller?