Is the Universe Infinite?

The shape of the universe is determined by a struggle between the momentum of expansion and the pull of gravity. The rate of expansion is expressed by the Hubble Constant, Ho, while the strength of gravity depends on the density and pressure of the matter in the universe.

If the pressure of the matter is low, as is the case with most forms of matter we know of, then the fate of the universe is governed by the density. If the density of the universe is less than the “critical density” which is proportional to the square of the Hubble constant, then the universe will expand forever. If the density of the universe is greater than the “critical density”, then gravity will eventually win and the universe will collapse back on itself, the so called “Big Crunch”.

However, the results of the WMAP mission and observations of distant supernova have suggested that the expansion of the universe is actually accelerating which implies the existence of a form of matter with a strong negative pressure, such as the cosmological constant. This strange form of matter is also sometimes referred to as the “dark energy”.

If dark energy in fact plays a significant role in the evolution of the universe, then in all likelihood the universe will continue to expand forever.

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  1. A very Interesting doco… well presented ..a must watch , a good intro to try and understand the near impossible concept to grasp!!!! don’t bother with the idiotic comments below !!!

  2. So does this mean that somewhere out there, in the infinite reaches of the the universe, G-Nuts did in fact watch this documentary, and Trollslayer liked that, and somewhere even more out there Angela is suitably ashamed, and somewhere else peanutaxis abbreviates “you are” correctly, and even further afield Ziggy discovers that God’s parents were completely cool with His life choices, and Ziggy comes here and tells everyone that He is so happy that He is throwing a slamming party to celebrate, and we all say “Yay, good for you God, good for you. He is such a great guy, and such a great dancer too. This party is going to be fantastic. Hooray.”?

    • Wait! Peanutaxis’ grammar was fine… it was Troll slayer with the dodgy abbreviation! Does this mean the universe is a hologram? Therefore, am I real, or is this just a simulation? Must I still drink this cup of tea, or will I be splitting off an entire new parallel universe if I don’t?… Because, quite frankly, it’s cold and tastes kind of bad. I would prefer to tip it out, even though when it’s warm it is actually a very nice cuppa. But is there a place where it isn’t?… Food for thought, food for thought.

  3. Recent data from the Large Hadron Collider at CERN show promising evidence that God is a homosexual. One more point for the science guys.

  4. Angela, are you refering to the god that brings children into the world and gives them terminal cancer?

    Maybe you can tell me who buride the millions of rotting bodies after the Noahs flood?

  5. That was painstakingly, braniac awesome… Love it!

  6. G-nuts

    Your an idiot.

    Thanks for taking the time to let us know your not going to watch the documentary.

  7. What do they have to support their “theory”? Nothing! God created the heavens and earth! If the Earth was created in a big bang, everything would be spinning the same way. (a law called the angular momentum) If a spinning object breaks apart while spinning. Everything that broke off will be spinning the same way…. Well, there are galaxies and moons spinning in both directions! This is impossible if the big bang theory is true! Nope, I am sorry people. There is a God and he created this universe and all of space!

    • @Angela FIrst of all, the big bang theory can be proven in a number of ways. While it is flawed and some can argue that the theory of dark matter is an ad-hoc-solution it is still lightyears ahead of any religious “solution”. Still, that´s the beauty of the scientific method: There are no sacred truths and if a theory does not longer hold against given facts it is no longer a viable theory.
      And no. You are thinking of Big Bang as a an explosion. Big Bang was an expansion of everything and is built on the hard evidence that can be seen by everyone: The distances between the galaxies are expanding. And the expansion is accelerating. If you know about the doppler effect, this is a theory which is kinda hard to break down. Ergo: Big Bang theory has lot´s of evidence, something that cannot be said about your god. If you wanna believe in an immaterial tyrant that rules everything and everyone that´s fine. But don´t use non-dogmatic terms like “evidence” to claim that scientific theories are wrong, you will only be a target for trolls.

    • You are unashamedly uneducated. Which is predictable, given your beliefs.

    • You are unashamedly uneducated. Which is predictable, given your beliefs.

    • THERE IS NO GOD…..

  8. You can watch this doc forever

  9. I just read the description and feel like I don’t have to watch the documentary…

    • I see what you mean, but that was just a weird description. The End Of The Universe part didn’t even start until about two-thirds of the way through.
      Pretty interesting in a fairly entertaining way!