How Old is the Universe

[neutralino]

although i answerd less than 13.7 billion but the more i think about it the more confused i become

you see we as a the human race created the definition of time itself without some form of clock or timer we would just know day and night therfore surely time began when WE created the means to tell it

can we really measure such huge timescales or is it all just clever guess work?
this may sound a stupid comment but the idea of time 'existing' is something that has puzzled me for years
im only 24 and ive had no college or uni experience so pls excuse my somewhat simple thoughts but id really love to hear others ideas on this subject

Scientifically speaking, time can exist even when we are not around to measure it. Yes, we invented the scale in which we measure time, but we can assume that this measure extends into the past as far as the beginning of the universe just as we assume it can extend into the future.

As for how we measure it: we use the standard model of cosmology, the big bang theory, and measure the recession of other galaxies from ourselves which gives us Hubble's law (or something close to it, with higher order corrections for the period of "inflation"). From this, we can then determine, roughly, how long the universe has been in existence. Of course, it'll not be exact, but we reckon it's something around 15 billion years.

[TheSolsticeParadox]

You have to look at this question from two different points of view to answer it, although no one really can.

technically, the universe has always existed if you believe in an ever-existing intelligent designer, because the universe existed before it was created in the mind of its creator.

If you don't believe that, then at some point it had to come into existence and therefore you can put an age on the universe. How? Nobody can give an accurate answer, they can just assume.

[austintorn@aol.com]

It has been 37 billion years and two days since the energy appeared, wherever and however, although it had not yet built into forms yet.

It turns out that the energy's fundamental substance was so small and so slow moving, compared to the size of a nucleon, that it took way longer than was thought to make a neutron, the FS having to slowly wind as a whirlpool until the density was such that it couldn't be compressed any further. (from Fluid Energy Theory)

[Hucknallite]

As the only person who has clicked the 8,000 years answer I feel that I should attempt to justify my position. The argument is too long to fit in here, so I will approach the answer through an analogy.

Consider you have just spent the past day experimenting with your cat in a re-run of Schroedingers experiment. You open the box, look at the cat and see that the cat is dead. How long has the cat been dead?

1) He died at some point before you looked in the box?

2) He died when you opened the box and had a look in?

The reason for the Schroedinger cat experiment is to make the point that the cat is in neither a living or dead state until the experimental observer takes a look in the box. Therefore it is the case that the cat dies when you open the box.

In a similar vein, when did the universe begin existing? If we assume the universe is a giant quantum system then until an observation is made the universe doesn't exist. Therefore the universe exists only at, and after, the moment that humans have evolved.

I figure this may well have been nearer 80,000 years ago rather than 8,000 years but it was the nearest option. Perhaps you could add 80,000 to the list of options?

[austintorn@aol.com]

'Everything' happened all at once, but only in a superposition of possibility in the timeless-formless state. Many paths went nowhere or not too far, but some achieved consciousness, like ours, which then made the possible become real-ized, through observation. A real slow-motion replay then occurred and is still happening.