Talk:Age of the universe

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Age in years?[edit]

It is not at all clear whether we are using the year as the common today's calendar year. What happens to time when we move close to the singularity or near the edge? Can we define time in another consistent fashion?

The article is not for experts: they do not need it. It is for common people who are simply curious. You need to be both simple and accurate. Whole system is relativistic and the concepts of space-time-mass-energy are all mixed up, right?

In the begining, there was no earth and hence the definition of year is invalid. After the earth disappers, the definition loses reference. I am confused in the same manner about mass and energy. chami 19:37, 2 November 2013 (UTC) — Preceding unsigned comment added by Ck.mitra (talkcontribs)

It uses "year" to have its common meaning (3.16 × 107 seconds, or today's calendar year). Is that confusing? It would never occur to me that year meant anything else. The parenthetical statement with the age of the universe in seconds removes any ambiguity for those who are confused. I think introducing any other meaning of year would be unnecessarily complicated (and a complication that the professional literature never gets into). —Alex (ASHill | talk | contribs) 22:30, 2 November 2013 (UTC)
Sorry that I was not clear enough. In the relativisitc sense, there is something called time dilation and 1s is not 1s all the time and everywhere. If I understand correctly, 1s is different for different people and at different times. We have to mention the observer (and I do not know what else) and the time will be different for different people. Is it correct? Or, all these time dilations and space curvatures do not affect the age? Let me put it another way. Suppose I was present during the birth and today I am somewhat near the middle of the universe (whatever that may be) and the age by my clock will be same for all? Even if I am close the edge or on earth? I need to look up the twin paradox but can you be more clear.-- chami 17:07, 4 November 2013 (UTC) — Preceding unsigned comment added by Ck.mitra (talkcontribs)
Like every reference I'm aware of, the age of the universe is expressed in this article in the present-day reference frame of the Earth (or, equivalently, the Sun, the Milky Way, the Local Group, or the Local Supercluster). The differences between what observers anywhere outside very local phenomena like black holes anywhere will observe are many orders of magnitude smaller than the uncertainty in the measurement of the age of the universe. —Alex (ASHill | talk | contribs) 19:54, 4 November 2013 (UTC)

The age and size of the universe[edit]

How is it possible to detect stars from 100 billion light years away if the Universe is only 13 billion years old? How can anything out there in the Universe be beyond where light traveling since the Big Bang has yet to reach? Is it possible for two objects to be become separated in space by more than the distance light could have traveled? 71.212.228.6 (talk) 20:50, 6 February 2014 (UTC)

I think the opening section of Observable universe is a good discussion of this. ErikHaugen (talk | contribs) 20:56, 6 February 2014 (UTC)
It's not so much that anyone can detect objects that far away, cause they can't. They cant detect anything beyond our horizon of 13 billion some odd lightyears. What they instead do is try to make it sound like the observable universe is much bigger by pretending to know an equation for very distant objects. Something like "space has expanded since the light of the distant object has reached us", so the "true" distance of the object is far greater than the observed distance. Fact of the matter is, there is no literal equation to figure the true distance because the light we're receiving is so ancient it may as well be useless to begin with. We can't even know the true location of any stellar object over 100 lightyears away because people haven't been recording these facets of cosmology long enough to make predictions. In short, it's just a bunch of humbug - don't worry. 24.176.180.116 (talk) 22:14, 18 February 2014 (UTC)
Yep. It's that space is expanding, not that the objects are traveling. Anyway, per WP:NOTFORUM, you're best off asking at the reference desk next time. This page is for discussing improvements to the article. Thanks.   — Jess· Δ 21:58, 6 February 2014 (UTC)

Age of the universe is truly unknown.[edit]

if interstellar objects are moving away from each other at an increasinly faster rate, and some even move faster than the speed of light, then that does not excplicitly or implicitly give anyone the ability to actually measure the age of the universe.

There is an extreme logical fallacy in thinking that "light hasn't existed long enough to reach us" beyond the 13 billion someodd lightyear horizon, when taking into consideration that those distant objects are racing away even faster, therefore implying that more distant light will never ever reach us - and that we can see will in fact only grow dimmer and fade out of view over time.

That is an extremely obscene leap of faith to assume the light will ever reach us with the existence of redshift measurements.

The speed of light is not tied to the age of the universe, for the speed of light was accurately measured far before the age of the universe, which solely uses the speed of light model itself. — Preceding unsigned comment added by 24.176.180.116 (talk) 07:37, 18 February 2014 (UTC)

Where is gravitational time dilation discussed in the "age of the universe"[edit]

Gravitational time dilation has been proven over and over, so if you have a change in the rate of time between the base of Empire State building and the top of the Empire State building, is the age of the universe different for the top of the Empire State Building then it is for the base of the Empire State building? I myself and not qualified to clarify this, nor do I know the answer. When we set the rate of the second, where is that rate set; sea level? Once you set the rate of the second then you get an age of the universe. Maybe the discussion of the rate of time doesn't need to be discussed on this page, but links should be created.

Katacomb (talk) 20:05, 7 June 2014 (UTC)

Oldest thing in universe[edit]

It is not correct that "the universe must be at least as old as the oldest thing in it". There could be things older than the universe which have entered the universe after its creation.Royalcourtier (talk) 19:56, 14 August 2014 (UTC)

  • Well that depends, doesn't it, on whether we're defining "Universe" to mean "everything which exists"? If so then whatever the older thing was was PA of our Universe before the rest of our Universe came about, and so simply pushes that oldest thingness back to its birthday. DeistCosmos (talk) 05:35, 27 October 2014 (UTC)

its all wrong[edit]

Sabbathart (talk) 13:30, 26 October 2014 (UTC)it is wrong to say that the universe is only 13.8 billion years old if it is true then the speed of light is not constant or was there ever a big bang its all wrong

  • Can you elucidate upon the proposition that the asserted age of our Universe requires some inconstancy of the Speed of Light? Blessings!! DeistCosmos (talk) 05:42, 27 October 2014 (UTC)

Possible mistake?[edit]

The method used to calculate the age of the universe has all fixed numbers except for the Hubbert Constant, which has been determined as 67.8±0.77 in the latest studies (December 2013). However when I calculate with H0=67.80, it gives me 14.422010323923x109 years as the age of the universe (4.5511468753554x1017 s). Let me elaborate:

1 pc (parsec) = 648,000 x AU / π
1 AU = 149,597,870.7 km
Therefore
1 pc = 3.085677581491 x 1013 km (approximately 31,000 billion km)
1 mpc = 106 pc = 3.085677581491 x 1019 km

This helps us find the coefficient of the expansion of the universe per second:
1/mpc = 3.2407792894448 x 10-20

Let's multiply by the Hubbert Constant:
3.2407792894448 x 10-20 x H0 = 3.2407792894448 x 10-20 x 67.8 = 2.1972483582436 x 10-18
1 / 2.1972483582436 x 10-18 = 4.5511468753554x1017 s This is the age of the universe in seconds.
1 year = 365.2425 days x 24 hours x 60 minutes x 60 seconds = 31,556,952 seconds
4.5511468753554x1017 / 31556952 = 14.422010323923x109 years .

So, either there's something wrong in these calculations (if so, please show me what), or the age of the universe is wrong on it's main page. Thank you :) --Universal Life (talk) 16:54, 1 November 2014 (UTC)

The expansion velocity of the universe isn't constant in time; it changes during expansion (slowing during the eras of radiation domination and matter domination, and speeding up during our current era of dark energy domination). So the naive calculation isn't exactly right, you need to properly integrate it backwards. WilyD 13:46, 7 January 2015 (UTC)

Capitalization of universe[edit]

There is currently a discussion about the capitalization of Universe at Wikipedia talk:Manual of Style/Capital letters § Capitalization of universe. Please feel free to comment there. sroc 💬 13:15, 19 January 2015 (UTC)

Discussion of capitalization of universe[edit]

There is a request for comment about capitalization of the word universe at Wikipedia talk:Manual of Style/Capital letters#Capitalization of universe - request for comment. Please participate. SchreiberBike talk 00:28, 4 February 2015 (UTC)

NASA seems to be the authority to me. "Capitalize the names of planets (e.g. Earth, Mars, Jupiter). Capitalize moon when referring to Earth's Moon, otherwise lowercase moon (e.g. the Moon orbits the Earth, Jupiter's moons). Do not capitalize solar system and universe." http://history.nasa.gov/printFriendly/styleguide.html CanadianLinuxUser (talk) 10:06, 5 February 2015 (UTC)
@CanadianLinuxUser: What you said has been discussed in SchreiberBike's link already. Words like universe and solar system already have been capitalized in many if not most of the Astronomy-related articles. Tetra quark (talk) 15:29, 5 February 2015 (UTC)
@CanadianLinuxUser: If you want your thoughts to count in the decision, please express your preference at Wikipedia talk:Manual of Style/Capital letters#Capitalization of universe - request for comment. SchreiberBike talk 22:20, 5 February 2015 (UTC)
It's unclear why NASA would be particularly authoritative. Monthly Notices, for instance, capitalises "Universe" to mean "this universe", and "Galaxy" to mean "this galaxy", but not to mean "a universe" or "a galaxy"; which is pretty reasonable. The proper name of our universe is "The Universe", so you caps it like any other proper name. (same as a moon vs. The Moon). WilyD 22:32, 5 February 2015 (UTC)

Notification of request for comment[edit]

An RfC has been commenced at MOSCAPS Request for comment - Capitalise universe.

Cinderella157 (talk) 03:23, 22 March 2015 (UTC)