Big Bang for beginners-9: Dark energy

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

In addition to the appearance of dark matter, another interesting development arose when observers tried to determine the curvature of the universe, an important fact in determining the ultimate fate of the universe.

To understand this consider, as an analogy, a ball thrown upwards from the surface of the planet. It will slow down as it goes up due to the gravitational attraction of the planet’s mass. But will the ball eventually fall back to the ground or will it escape from the planet and go on forever? The answer depends on both the speed of the ball and the size of the planet. For a given speed of the thrown ball, if the mass of the planet is below a certain value, its gravitational pull on the ball is not sufficient to bring it back and the ball will escape and travel out in space forever.
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Big Bang for beginners-8: Star formation and dark matter

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

In the study of our universe so far, one fact becomes resoundingly clear. Humans occupy a tiny volume of the universe. All our scientific theories have been discovered using data that has been generated within that volume. What gives us the confidence that these same laws can be applied to distant regions as well? One answer is that we have no choice but to make that assumption. Another is that when do make such an extrapolation we get a reasonably satisfactory understanding of the behavior of distant stars and galaxies, thus justifying our decision.
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Big Bang for beginners-7: What lies beyond the edge of the universe?

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

The idea of an infinite space that has always existed and in which everything else just moves around seems intuitively reasonable, at least to those who are comfortable with the concept of infinity. But the idea that there is no edge or boundary to the universe is much harder to grasp.

Going back to our raisin bread analogy, asking the question “What is beyond the edge of the universe?” is akin to asking what exists outside the space occupied by the dough. The answer is that there is no space outside the dough. The dough is all the space there is. This is where the raisin bread analogy starts to be misleading because we cannot help but view the dough as expanding inside the space of the oven, and it is hard to eliminate that unwanted extra image of oven walls. (If we wish, we can envisage a small portion of the dough and speak of the boundary of that portion alone, but that is not the boundary of space as a whole. It would be like speaking of the boundary of our Solar System or the Milky Way galaxy.)
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Big Bang for beginners-6: The evidence

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

Why has the Big Bang theory become the standard model for understanding the origins of the universe? In the 15th century and earlier, most people thought that the Earth was the center of the universe and that the stars were embedded in a celestial sphere beyond the outer planets and that the size of the universe was not much larger than the Solar System. The Copernican revolution (with the publication of his book in 1543) displaced the Earth from the center of the universe. This led to suspicions that the universe could be very large, possibly even infinite, but there were at that time no good theories to explain its origins and structure.
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Big Bang for beginners-5: Some conceptual challenges

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

Although the story of the Big Bang in its essence is quite simple and straightforward, it contains many fascinating subtleties that are worth exploring further. It is good to get some conceptual hurdles and misconceptions out of the way right now.

When we use the words ‘Big Bang’ it immediately conjure up certain images. We immediately think of familiar explosions, like bombs or firecrackers going off. We envisage a big noise and the exploding pieces hurtling away from the center of the explosion and spreading out into the surrounding space at great speed. This image captures correctly the idea of a hot compressed beginning with a fixed amount of matter spreading out through space and getting cooler and more dilute with time. But there are important ways in which the image is inaccurate.
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Big Bang for beginners-4: The speed of cosmic evolution

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

What may surprise people is how rapidly the universe went from a very hot initial state to one in which it was cool enough for atoms and molecules to form. If we push our theories back as far as we dare, bearing in mind that we have stretched them to the limits and that we may well be wrong in some aspects, the earliest time that we can speak of is 10-43 seconds after the Big Bang (called the Planck time). i.e., this is 0.0000… 0001 seconds (43 zeros in all, including the one before the decimal) after the Big Bang. In other words, it is a really tiny time. It is estimated that the temperature of the universe at that time was about 1030 degrees. That is 10 followed by 30 zeros, a really huge number.
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Big Bang for beginners-3: The basic story

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

The starting point of the Big Bang story is a cosmic event that started out small and expanded rapidly (like an explosion). This event brought into being the universe we now inhabit and produced all the matter that our universe is presently composed of, though not in its present form. The time at the beginning is arbitrarily set to zero.

We do not know what happened right at the very beginning (at time zero by our convention) because our known theories are believed to not apply right at the beginning. So our story begins very shortly after the Big Bang occurred. It is believed that what existed then were quarks, gluons, electrons, and photons that were moving freely around in a hot dense gas called a plasma. (There were also a few other exotic particles that I will ignore as they are not central to a basic understanding of the evolution of the universe). As the universe expanded over time, these quarks and gluons and electrons and photons eventually became the ordinary matter that we now have. No new matter was created after the Big Bang, but the form that the matter took did change dramatically.
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Big Bang for beginners-2: The nature of energy

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

In order to understand the Big Bang theory, we also need to have an understanding of the nature of energy in addition to that of matter that was discussed yesterday. The word ‘energy’ has a technical meaning in science but has also entered into the vernacular and thus has been used to mean many things. In everyday language, it usually signifies the source of the ability to do things, such as move objects or break them up or put them together. So gasoline provides the energy to run cars, coal the energy to heat things, and so on.
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Big Bang for beginners-1: The nature of matter

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

I was recently asked by a relative to provide a simple explanation of the Big Bang theory ‘in words of one syllable’, i.e., without using jargon or esoteric scientific concepts and in a way that it could be understood by non-scientists. So here goes my attempt at fulfilling that request. In doing so I have tried to follow a paraphrase of Einstein’s dictum that says that when explaining something we should make things as simple as possible, but not simpler. In other words don’t distort in the search for simplicity. In trying to achieve this goal, I have created a multi-part series. (I promised my relative that my explanation would be simple, not short!)
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Overdependence on technology

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

I like a lot of the conveniences that modern technology provides. At the same time, there is so much new stuff that is coming out that I feel reluctant to waste my time learning things that will prove to be transient. I am also somewhat cheap and tend to wait until the dust has settled and only the truly useful is left standing before spending money on it. So an early adopter I am not. I tend to keep an eye on trends but not adopt anything new unless I think I really need it or it solves a problem that I have or it looks like something that will really improve my life.

Personal GPS navigation systems have so far not passed that threshold. Yes, I can see that it might be fun to have but so far I am not persuaded that it is a must-have.

Last Friday, someone knocked on my office door. He said that he was looking for a conference that the university was hosting. I knew that there was nothing going on in my building and asked him why he had come there. He said that this was the place that his GPS has sent him to. I asked him if he could give me the name of the building where it was to be held or the people organizing it so I might be able to help him more easily. He said no. He had simply plugged some information into his GPS device and followed its directions to the end, which happened to be my building.

It so happened that I was able, from the topic of the conference, to track down the exact location and send him on his way. But I marveled at his total dependence on technology.

He is not alone. Recently my cousin was driving to New York City from Toronto for a wedding that I also attended and depended totally on his GPS system to get him there. For some reason, the street address of the hotel was not the address that you are supposed to insert into the GPS to get accurate directions, but he overlooked that and as a result he got lost and spent several wasted hours wandering around NYC (at the end of a long drive from Toronto when everyone in the car was already tired and irritable) until he found the hotel. It had not occurred to him to carry a map with the location of the hotel on it or to use MapQuest or similar sources to gets directions as backup.

While these two cases were benign, overdependence on GPS can be potentially deadly as one Oregon couple found when they blindly followed their GPS directions into a remote forest road and became stuck in the snow for three days before they were rescued.

I myself do not use GPS because I find that I am perfectly able to get to places with just street maps or with help from MapQuest. I also dislike the idea of voices breaking into my consciousness when I am driving and telling me what to do, when most of the time I don’t need directions. Before I leave to go anywhere unfamiliar, I make sure that I have located my destination on a map and created a visual map in my head, and I take actual maps with me as a backup.

There s nothing wrong with using GPS. What surprises me is that some people are totally dependent on it and have no plan B, no backup, if the GPS goes awry.

POST SCRIPT: Wedding speeches

Over my lifetime I have attended many weddings and listened to quite a few speeches and I must say that That Mitchell and Webb Look captures their over-the-top praise nature well.