If Time Is Infinite Where Did Matter Come From In The First Place

Recent update on age of the universe: 13.7 +/- 0.2 Gy (based on cosmological modelling [reference? - http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v422/n6928/full/422108a_r.html&filetype=&dynoptions= (might require a subscription) ]).

If the universe is really only 16 billion years old, and if our galaxy takes 250 million years to rotate once, how could it have rotated enough times to form a spiral shape?

A BIG assumption is that the spiral pattern results from the stars trailing as the galaxy rotates. This isn't what prevalent thinking is, for actually the inverse reason of the above: in that amount of time, spiral patterns would have destroyed themselves through over-winding. Spiral arms only wrap around at most one-and-a-bit times, you know. They probably result from density waves: small blotches of gas being driven together.

If the galactic density wave causes stars to ignite then how long can those stars burn? If they burn too long then the high pressure area wouldn't look any different from the low pressure area. And wouldn't a galaxy be bigger when it was young?

The thing is that the brightest stars are exceedingly short lived - maybe something on the order of a million years. Stars like the sun are scattered all across the galactic disk, but don't contribute anywhere near as much to the glow, so brightness is a pretty good tracer of star formation regions. The density wave model is fairly well supported by the evidence. I'm not quite sure what you mean about young galaxies being bigger, though.

If the universe is really only 16 billion years old, and if our sun is 5 billion years old and is expected to last 10 billion more, and if our system is made of dust from the supernovas that destroyed former systems (we have gold and uranium in them thar hills), how could we have had time before this solar system was created to create and destroy other ones?

Our sun is not the kind of star that will make elements heavier than iron; actually, the sun is unlikely to make any elements heavier than helium. The Sun will end its days as a white dwarf which will then just cool down. For heavy elements to be released, the star must actually explode in a a supernova. This requires a star at with at least 10 times more mass than the Sun. However, a star's lifetime decreases very rapidly with increasing stellar mass - those stars that will produce heavier elements in supernovae explosions last nowhere near the sun's expected 10 billion year lifespan but rather will have 'main sequence' lifespans measured only in tens or hundreds of millions of years.

"16 billion" comes from this statement: The farthest visible things are primitive proto-galaxies called Quasars. They are 15 billion years old. Therefore they formed in 1 billion years, and the universe began before that.

Now what gaps appear in this reasoning? It couples the idea "size of the visible universe" with "age of the visible universe", under the idea that the universe could only have been seen for the amount of time it takes light to arrive so we can view it. Is this a solid argument?

[That's solid, but it doesn't demonstrate that the universe is not much older than <age of the quasars> + <light-distance to the quasars>, only that it's at least that.]

The issue with quasars is a bit more complex than just saying 'they are 15 billion years old'. In fact, the age of quasars is conjectural. The actual parameter that is measured is the quasar's recessional velocity as measured by the degree to which light from the quasar is RedShifted. It was first observed (by EdwinHubble) that the recessional velocity of very distant objects is proportional to their distance. This is a consequence of the ExpansionOfTheUniverse. If you know the HubbleConstant? (current estimates are pretty good) then from measuring the RedShift of the quasar you can calculate its distance. Since light travels with finite velocity, if you know the object you are looking at is 15 billion light-years away, it follows that the light you are observing from that object is 15 billion years old. However, it all hinges upon the value of the HubbleConstant? and its relation to universal expansion. Although the observational parameter of the quasar (the RedShift) does not change, the interpretation of what that shift means in terms of distance, and hence the inferred age of the quasar, is subject to reinterpretation. -- AndyPierce

Putting aside for a moment the physicists who tell us that time did not exist prior to the big bang, it strikes me that perhaps the only reason that we human beings tend to handle 'infinity forward' better than 'infinity backward' is the fact that we are surrounded by things that appear to have beginnings.. including ourselves. -- MichaelFeathers

Just for fun, I tried asking the title of this page on google. Many of the resulting links were useless, but a few interesting ones were:

[As a kid, I learned, hydrogen star -> Helium star -> Carbon star -> Lead and collapse. And there are many more reaction chains!]

From the "Ask The Space Scientist" page: For a very massive star, the core temperature become relentlessly higher as the core collapses and gravitational potential energy is converted into thermal, kinetic energy. Here are the approximate reactions and their temperatures: 

  Hydrogen-burning to helium ................ 100 million  (degrees)
  Helium+Helium+helium to carbon ................ 200 million
  Carbon+Carbon to magnesium.............. 500 million
  Helium+magnesium to silicon................ 800 million
  Silicon + carbon to argon.................. 1 billion
  Argon + carbon to iron................... 2 billion
  Iron + iron   death..................... 3 billion+
...also, in response to a question "When did the elements for forming planets first form after the Big Bang?", the answer was:

Within 1 billion years or less. As astronomers continue to observe more distant galaxies, they are discovering that galaxies with 'solar abundances' seem to be still detectable even at redshifts near the limit of what they can spectroscopically study. Evidently, the first generation of massive stars to form a few tens of millions of years after the Big Bang, were able to enrich the interstellar medium to nearly solar abundances very quickly. It would then have been possible to form the first planets within a few hundred million years after the Big Bang!

Other pages stated that lithium was the heaviest element created in the Big Bang, and that elements heavier than iron were created in supernovas. Lithium only in very low abundance and very sensitive to the initial conditions in the 'big-bang'. Explaining the lithium abundance is actually a very stern test of cosmological big-bang theories.

"Science says, 'Just give us one free miracle, and we can explain everything else.'" -- TerenceMcKenna on the "Big Bang" Theory

Please note that time and matter are inseparable. Time is change in matter; if matter did not exist (or existed but did not change), time is meaningless.

The wording "result of" is inappropriate - it suggests causation. If matter-energy is conserved, one would expect time to be unbounded, with no causal relationship between matter-energy and time.

Care to explain the reasoning behind the first part of that last sentence?

Conservation of matter-energy suggests no true beginning or end of the universe, hence no associated beginning or end of time. Even a true beginning (i.e., nothing before the big bang) wouldn't justify saying that time was caused.

Except that this is not true. Conservation of energy only suggests that the total energy of the universe is zero. Which is the case. Gravitational potential energy is negative and negates all other forms of energy.

The total value of the universe across all of its conserved quantities must be precisely zero so that the universe is literally equivalent to nothing. If it were ever to be found off from zero, even by so much as a single electron, this would be proof that our universe spawned from another universe.

What is true is that spacetime isn't caused by matter. That's because causality is much too weak a relationship to describe what matter does to spacetime. Matter logically implies spacetime.

Time is not thought to be infinite. It was created with the big bang. ALSO conservation of energy and matter only applies when the curvature of the universe in constant. During the big bang, this was not true.

"[Time] was created with the big bang." How long did this take? <-- as long as it had to. You're missing the point

See also: TheEarthIsFlatButSpaceIsCurved, WereAllTravellingAtTheSpeedOfLight, WatchingTheStarsChangesTheWayTheyShine, SteadyStateCosmology

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