Beginning and End of the Universe

  • Universe History
  • The diagram below outlines the major Eras of the Universe according to the Big Bang Theory.
  • PLANCK ERA: this is the time just before the Planck time (1/10^43 seconds). In this era, random energy fluctuations were so large that we cannot explain the physics at these high energies. Energy and mass are equivalent and so energy fluctuations cause changes in space and time. These fluctuations arise naturally out of the Heisenberg Uncertainty Principle. These early rapid fluctuations are large enough to destroy our theories. Explaining the Planck Era is one of the goals of String Theory (the theory of everything). So far, we do not know what happens during this time.
  • GUT ERA: GUT stands for grand unified theories. This is a theory that unites three of the four known forces. The four forces are gravity, electromagnetism, the weak force, and the strong force. GUT combine the strong force with the electroweak force (the combination of weak and electromagnetic force). We have learned that the forces are seperate but under high temperatures they come together. So the GUT era is when gravity and GUT force controlled the Universe.
  • During the GUT Era is when we think INFLATION happened: that point were the Universe underwent a dramatic expansion. When the strong force froze out of the the GUT force (like ice crystals forming on water), that may have caused an enormous energy release. Inflation is an important aspect of the Big Bang since it explains many problems: the structure problem, the smoothness problem, and the fact that we are at the critical density.
  • ELECTROWEAK ERA: this era is when the electromagnetic and weak forces were still united. Conditions of this era were actually achieved in a particle accelerator in 1983 (which one a Nobel prize), and it was predicted early (which gave rise to a Noble prize in 1979 to Weinberg). Thus, we have direct evidence of the electroweak era from experiments. We have not been able to go much beyond these energies.
  • PARTICLE ERA: during this era the Universe was just the right temperature for particles to be created and destroyed continuously. What happens is the photons have the right energy to come together and annihilate each other to form matter and antimatter. And then the matter and antimatter smash together and form gamma-rays. This continues until the Universe cools enough such that the particles do not have enough energy anymore to annihilate each other, and we are then stuck with whatever was left at that point.
  • At the end of the particle era, there were slightly more protons than antiprotons. For every billion antiprotons there were a billion and one protons. Another way to look at it is one billion protons were annihilated with one billion antiprotons to make a billion photons, which would result in leaving one proton in the end. It is this slight excess that makes up most of the matter in the Universe.
  • NUCLEOSYNTHESIS ERA: during this era, protons and neutrons would come together for a short while before interactions broke them up again. Essentially, the Universe was a big continuous fusion reaction. This era ended when the Universe was 3 minutes old. The diagram below shows which elements the Universe could form (this is mainly based on our understanding of nuclear reactions). It was at the end of this era that set the chemical composition of the Universe.
  • ERA of NUCLEI: during this time, protons and neutrons were together in nuclei. Electrons would form an atom with this nucleus but would soon be ionized as a photon hit it. Thus, neither an atom could form nor could a photon travel very far. At the end of this era the Universe was cool enough that photons did not instantly destroy atoms and very quickly the electrons found the nuclei, and the photons were free to travel around. This is what makes the cosmic background radiation and it happened at a temperature of 3000 Kelvin (about the temperature on the surface of red giant stars).
  • ERA of ATOMS: this era is marked by the first structures beginning to form and it blends in with the ERA of GALAXIES. This is about the time when astronomers take over from physicists in terms of trying to explain the Universe.
  • The era of atoms lasts for a long time and is sometimes referred to as the DARK AGES: that point were we have essentially no information on what was going on. Galaxies had not formed yet and so we don’t see bright objects. However, gamma-ray bursts may allow us to penetrate into this era. It is during this era that maybe black holes played a key role in terms of galaxy formation. Also, dark matter is crucial to understand as well.
  • Our most distant object (a galaxy) is at a redshift of 6.4, or when the Universe was about 1 billion years old. There have been some speculative claims of more distant objects. The cosmic microwave background is at a redshift around 1100, so we still have quite a ways to go to meet with that.
  • There are a few missions planned to observe the dark ages. Because it is at such a high redshift, the important features are shifted out of the normal wavelengths that we like to observe in (i.e., the optical). Thus, we need to use infrared obsrevations to gain any info about this era. Also, the since it is the era of atoms, the Universe maybe filled with gas and so it may be difficult to see anything in the optical region. Europe has a mission called Herschel Space Observatory , which was launched in 2009. The US is planning a follow-up to HST called NGST. Both of these mission concentrate in the infrared since the optical region is so heavily obscurred.
  • One important question is what was the first structure to form after the era of atoms. There are arguments that suggest both small and large galaxies. Some say that black holes would be the first and then they seeded galaxy formation (this would logically lead to a connection between galaxies and black holes so it is enticing). We don’t know the answers yet.
  • One important point is that since everything that we learn about the Universe comes from light (photons), if there are no photons there is no information. Thus, before the end of the era of nuclei, we have no information since the photons were trapped. We will never see this era of the Universe with photons, but maybe gravity waves (?).
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Astronomy Picture of the Day | The Dark Tower in Scorpius

Image Credit & Copyright: Thomas V. Davis

This object is an obscure cometary globule in Scorpius. I think the name came from John Gleason who imaged it in h-alpha. Actually only a few images of it exist, all I believe taken in h-alpha except for David Malin’s color film version. Its a cool target and seems to be the southern hemisphere’s equivalent to Vdb 142 (IC1396A). I hope you enjoy it.

Bright rimmed globules and their more evolved cousin the cometary globule represent fascinating dynamic structures formed by the interplay of cold molecular clouds and hot ionizing stars. Typically the head of the globule faces a hot O-type star. Intense radiation from the star boils away lower density gas from the head. The evaporated rim of gas becomes ionized by the stars ultraviolet flux forming a bright glowing rim we associate with many of these globules including CG4. Intense stellar winds from the ionizing star evaporate gas and dust away from the head forming the “tail” and completing the cometary shape. The globules are known to be the birthplace of low mass stars. Stars form within the globules by the mechanism known as “radiation driven implosion”. This process occurs when ultraviolet flux from a hot star compresses surviving clumps of cold molecular gas eventually causing collapse and core formation within the dense compact clouds. Lower and intermediate mass stars ultimately form from the compact gas and dust within the globules.

In silhouette against a crowded star field toward the constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across the gorgeous telescopic view. Known as a cometary globule, the swept-back cloud, extending from the lower left to the head (top of the tower) right and above center, is shaped by intense ultraviolet radiation from the OB association of very hot stars in NGC 6231, off the right edge of the scene. That energetic ultraviolet light also powers the globule’s bordering reddish glow of hydrogen gas. Hot stars embedded in the dust can be seen as bluish reflection nebulae. This dark tower, NGC 6231, and associated nebulae are about 5,000 light-years away.

Paying by Prayer

Original ad: 

Help me! I’m in desperate need of a Blu-ray player. I don’t have a lot of money so if you want to give me one for free, that would be great. In return I will say many prayers for you! Please e-mail me @ ***********@verizon.net

From Me to ***********@verizon.net:

Hey there,

I have an old Blu-Ray player I don’t use anymore. Are you interested?

Mike

From Cathy ******** to Me:

Yes I am very much interested! What brand is the player and is it free?

From Me to Cathy ********:

Cathy,

It is a Samsung player, and whether it is free or not depends on you…how many prayers are we talking about here?

Mike

From Cathy ******** to Me:

I will say many prayers for you!

From Me to Cathy ********:

Yeah, I got that. Specifically, how many prayers? This Blu-Ray player wasn’t cheap. I’m thinking, 50 Our Fathers and 50 Hail Marys every day for a year. Does that sound good?

Mike

From Cathy ******** to Me:

Mike, the quantity of prayers is not important – it is the sincerity and power of the prayer that matters. I will be genuinely thankful and show this through my prayers!

From Me to Cathy ********:

Sorry, but I’m not settling for anything less than 50 Our Fathers and 50 Hail Marys per day. The last guy I gave my plasma TV to gave me that “sincere prayer” crap but I don’t it worked at all. My wife’s breasts still aren’t bigger and my lottery tickets still aren’t winning. The only thing that matters is the amount of prayers that you say. It is your choice; 100 prayers a day or no blu-ray player.

Mike

From Cathy ******** to Me:

I think you are misunderstanding the purpose of prayer. Surely you can’t expect me to say that many prayers – it would take all day!

From Me to Cathy ********:

I’m willing to cut you a deal, Cathy. I’ll only ask for 50 prayers a day, but in return, you have to come say grace whenever I eat dinner. I’ll accept you saying grace for me over the phone if I happen to be eating at a drive-thru fast food place.

I’ll also throw in my copy of “Drag Me to Hell” on Blu-Ray.

Mike

From Cathy ******** to Me:

Please stop. You are being preposterous.

From Me to Cathy ********:

Cathy,

My apologies. I guess you are right, I am asking for a bit too much. Here’s what I’ll do. I’ll go by what my priest made me do the last time I confessed to stealing a Blu-Ray player. He made me say 20 Hail Marys and 10 Our Fathers, but I think the Our Fathers were because I pistol-whipped a guy while I was stealing it. Since I didn’t have to pistol-whip anyone this time, I’ll give it to you for only 20 Hail Marys. How does this sound? This is practically face value in prayer.

Mike

From Cathy ******** to Me:

Oh my lord, you have lost your mind! I will get a bluray player elsewhere.

via dontevenreply.com

Curse of the Ninth

Anton Bruckner died after writing his ninth symphony. So did Beethoven, Schubert, and Dvořák. In the 19th century, a superstition arose that a quick death awaited anyone who wrote nine symphonies.

Arnold Schoenberg wrote: “It seems that the ninth is a limit. He who wants to go beyond it must pass away. It seems as if something might be imparted to us in the Tenth which we ought not yet to know, for which we are not ready. Those who have written a Ninth stood too close to the hereafter.”

Mahler figured he could escape the curse with a decoy: When he finished his ninth, he retitled it “The Song of the Earth” and wrote a second “ninth” symphony. When nothing happened, he told his wife “the danger is past,” started a new work — and died.