Talk:Timeline of the Universe
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2.1 Okay that does it |
Comments not showing up?
I saw some relevant diff's on the talk page that "disappeared" into the áether. One of the more interesting comments is the following. Can we incorporate this into the main article? I'd prefer it not to be word-for-word as it is a bit of dry factual information (from what I can tell). -- Zalasur 01:21, Apr 27, 2005 (UTC)
Comment on the web page
The hypothesis relies crucially on the type of dark energy in the universe. The key value is the equation of state w, the ratio between the dark energy pressure and its energy density. At w < -1, the universe will eventually be pulled apart. First the galaxies would be separated from each other, then gravity would be too weak to hold individual galaxies together. Approximately three months before the end, solar systems will be gravitationally unbound. In the last minutes, stars and planets will come apart, and atoms will be destroyed a fraction of a second before the end of time.
The authors of this hypothesis calculate that the end of time would be approximately 3.5×1010 years after the Big Bang, or 2.0×1010 years from now.
-- http://en.wikipedia.org/wiki/User:Kzzl
Let's get 'er done
I wanna merge the articles. Let's get 'er done. -- Zalasur 07:24, Mar 23, 2005 (UTC)
Okay that does it
Let's merge Timeline of the Big Bang to Timeline of the Universe. I took a re-review. Let's get 'er done. -- Zalasur 00:07, Mar 16, 2005 (UTC)
Hmmm
I'm beginning do have doubts about the layout I chose for the page. Too many entries in the TOC perhaps? Too many bullet points definitely.
-- Zalasur 09:31, Mar 10, 2005 (UTC)
References References References
Hm I gotta beef up the References section... soon it will be done...
Otherwise, I think I'm almost done with this one :)
Mostly done with the major edits
I don't see any reason why there needs to be any further major edits to the page. The Black Hole, Dark, and Photon Ages all need some padding out, and the References section is practically non-existant (I would like to find viable external references) but that can be done with minor edits. I think I would like to add a picture of a black hole to this article (after the picture of the asteroid but before the picture of the photons), but the only reason I haven't is because I can't find a good picture on Wikimedia's list of files, so I have to find a public domain one somewhere else or draw one myself.
I'm kind of curious about what to do with the "Timeline of cosmological eras" article... the information is highly redundant and I'm pulling most my data from there as far as when everything occurred. I think the two can be merged.
-- Zalasur 23:19, Mar 1, 2005 (UTC)
I need help
I could use references, corrections, and such. As of now I will focus on Wiki's formatting features to make this "look" better. This is my first Wikipedia article (although I may say it's a rewrite of an older article, it's really just a complete 98% rewrite).
Things I think I will fix (and play around with)...
1) formatting.. I need to learn Wiki's formatting guidelines and make this article "Feature Article" material. I need something to play around with and this is better than the Sandbox.
2) references... yeah let's make this a serious article. got any good sources? I could use 'em
3) pictures... picutres are pretty... mmmmmm donuts too
So who's with me on this one?
--Zalasur 20:45, Feb 27, 2005 (UTC)
I updated the page
I ran across this one one and kinda scratched my head... "it needs work" I thought. I pretty much updated everything and removed anything human-centric. I'm thinking that at the end of this I can write up a snap-shot (as of this day, the Universe is X old, the Milky Way is Y old, etc etc etc) or put that in another article.
Also needed (this will help me remind myself):
- more references (and more relevent ones too)
- more specific timelines... I need to look up some numbers to tack onto the events in terms of billions of years or something
- The "ultimate fate of the universe" section
- clean-up of grammar, spelling (oops), terms, and a little structural overhaul
Probably more too... whee
--Zalasur 05:14, Feb 27, 2005 (UTC)
Exponential format
I noticed the article uses "base ^ exp" format because neither "base<sup>exp</sup>" nor "<math>base^{exp}</math>" display correctly in the TOC. :( Can we make a suggestion to the MediaWiki people to allow it? It looks really bad the way it is now. :| —Mar·ka·ci:2005-03-12 11:18 Z
Bright side
At least it let me use the caret in the TOC. I don't think I would have liked to type out 10^150 by hand. :) -- Zalasur 18:05, Mar 12, 2005 (UTC)
Older comments below
Anonymous
I just changed info about formation of earth from 3.8 to 4.5 billion years ago and origin of life from 2.5 to 3.5 billion years ago.
While it is true that science currently predicts the uiverse to expand forever and not collapse back into itself, is the prediction of a googol years just someone fooling around with this article? -- Modemac 23:46 Mar 2, 2003 (UTC)
Anonymous
From the article:
- 2 billion years from now: life ceases to exist on Earth
What is the mechanism for this? Increased/decreased solar output? Cite, please.
Anonymous
- 2 billion years from now: life ceases to exist on Earth
Removed unless someone presents a justification. Also rephrased bit about future of the sun.
Comment
Moved here
- Since human observations cover a very short time interval and relatively short distance, making detailed predictions about the distant future or distant past is difficult. Humans can only observe a fraction of the total universe, and the observations cover a very short time interval. It is possible that our current understanding of physics contains errors that are only noticeable on a very large time scale or very large astronomical scale.
We can see back 13 billion years and 13 billion light years across. Yes, it's possible that our physics is wrong, but you could add that disclaimer to all science articles.
Anonymous
I don't know how this will hold up, but it seems that very recent work indicates that the universe is about 14.7 billion years old. Maybe add this as an external link for the time being? [1] (http://news.bbc.co.uk/1/hi/sci/tech/3732157.stm) --65.146.234.124 09:22, 27 May 2004 (UTC)
Humans
Shouldn't the stuff on Humans and Earth be on Timeline of Earth? It's not relevant to the evolution of the Universe itself. --Tothebarricades.tk 16:43, 20 Sep 2004 (UTC)
Wikipedia
Not that I'm doubting the significance of the Wikipedia or anything, but to have it listed here on the Timeline of the Universe? Oberiko 22:11, 26 Sep 2004 (UTC)
a bit messy
I think this article is a bit messy and needs some work. It should concentrate less on humans and even the earth; after all, earth only forms 10-30 (or something) part of the universe. Some of the more interresting events are on the Longer times page.
contradiction in wikpedia
the timeline here doesn't suit the one in the article "timeline of evolution" in some cases, like that of the appearance of molecular life is dated here for 600 BP whereas in "timeline of evolution" it is in 1,000 BP.
I really don't know a lot about it, but somebody should check it out and fix it.
Ido Hartogsohn
further contradiction
The section as follows appears to conflict with other articles, notable the Timeline of the Big Bang.
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The Reionization Epoch: 300,000 years
Light energy from the initial expansion of the Universe stretches out and weakens to the point where matter finally dominates in influence (this is the generally agreed-to end of the Big Bang era). Telescopes are not able to see this far back into the history of the Universe because the deionization of hydrogen caused "empty space" to be opaque to light in most wavelengths. Instead scientists must use particle accelerators and theoretical physics to infer what occurred indirectly. The most direct evidence scientists can measure from the Big Bang is the cosmic microwave background radiation that is uniformly pervasive throughout the Universe. It is thought this background radiation is actually a snapshot of the early Universe and provides the best evidence of the creation of matter during the early epochs.
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The other page lists 300,000 years as the DE-ionization period, which caused empty space to be transparent to light, not opaque. Can someone a bit more knowledgable clarify this?
Anonymous
At around 300,000 years, the universe became transparent to light because atoms formed from the electrons and light nuclei. Before this, the universe was opaque because the particles could abosrb and reemit any wavelength of light with a random change in direction between the absorbed and emitted photons.
- At 300,000 years the universe became cool enough for atoms to form. The electrons in the atoms can only absorb specific wavelengths. This allows most of the light to pass by, making the universe transparent in most wavelengths.
- So, it went from ions to atoms. This section also should not be named Reionization Epoch. The reionization happened later as the first stars converted atoms back to ions. Maybe reionization was confused with recombination, a word used for deionization.
- I'll fix the section and add another one for the later reionization by stars.--BrendanRyan 01:29, 8 May 2005 (UTC)
- I did the changes about deionization. I found that there was already a section that mentioned reionization by the first stars and galaxies.
No superscripts in TOC
Apparently the superscripts (exponential notation) in the headings don't show up in the Table of Contents, so you get: "The Planck Epoch: 10-43 seconds" "The Degenerate Age - 1040 years"
This is confusing. Of course nobody will be fooled for long, but it would still look better if there were something to distinguish it. Unfortunately, I can't think of any except "10^-43 seconds", which to most people would probably be even more confusing.
Any ideas?
Nickptar 01:37, 9 May 2005 (UTC)
The Big Bang and matter formation
The subsection, The Planck Epoch: 10-43 seconds, first sentence should be reworded to say: "..., and everything in it, could have possibly begun with the Big Bang...". I suggest this because it is not proven absolutely that the Big Bang is really the cause of the formation of the Universe. Note the fact that it is usually called the Big Bang Theory. Hoekenheef 21:51, 15 May 2005 (UTC)
- This whole timeline is based on the Big Bang theory. If some other theory (divine creation, Steady State, some exotic stuff I don't know about) is true, then at least the entire early part and possibly the entire latter part are invalidated. Nickptar 22:38, 15 May 2005 (UTC)
- So you're basically saying that since this is what the article is about it should be stated like that? (just clarifying) Hoekenheef 23:09, 15 May 2005 (UTC)
- Pretty much. It already says "according to prevailing scientific theory", and I've clarified that this means the Big Bang. Nickptar 23:49, 15 May 2005 (UTC)
- Okay, well then in that sense the phrase is fine so I will make no further inquiry about this. Hoekenheef 10:22, 16 May 2005 (UTC)
- Pretty much. It already says "according to prevailing scientific theory", and I've clarified that this means the Big Bang. Nickptar 23:49, 15 May 2005 (UTC)
- So you're basically saying that since this is what the article is about it should be stated like that? (just clarifying) Hoekenheef 23:09, 15 May 2005 (UTC)
related question: what was in existence during the Planck Epoch? In a theory such as string theory, is it proposed that strings existed at the earliest times? --Memenen 03:18, 8 Jun 2005 (UTC)