What Does It Mean?

It’s worth taking a pause right now to consider where we’ve come. We started with a brief biography of physics, moving from the earth-centered view of things to a vast universe that might be just one of virtually infinite universes. This view is called the multiverse.  We’ve seen that the Big Bang Theory is currently the predominant theory on how the universe came into being. It is now almost universally (no pun intended) recognized as the accepted theory because it and it alone explains what we observe.

By running the Big Bang backwards we are led to an inescapable conclusion: that everything was all together in one place at one time. That instant in time is the Big Bang itself, the instant when immeasurable energy exploded. Both space and time began at that instant. We’ve speculated on what caused the Big Bang and we’ve run into a knotty problem that occupies physicists today. How do we reconcile General Relativity and String Theory? Is there one unifying theory? This unifying theory is given the name of the Grand Unifying Theory, inelegantly known as GUT. Too bad scientists have fallen prey to the seemingly insatiable desire to create an acronym for everything.  But science is no different than anyone else. We have reduced the Supreme Court of the United States to SCOTUS, which looks an awful lot like scrotum. But I digress.

We have seen that there are three possibilities for why the universe is the way it is. The first is that it is a random event. After the Big Bang there were almost infinite possibilities for how the universe could turn out and it turned out this way. In other words, we won the cosmic lottery; otherwise we wouldn’t be here to ask such questions. The second possibility is that of the 10500 universes that exist in the String Theory-predicted multiverse, the odds are that at least one of them would be like ours, that is, capable of sustaining life. The final possibility is that, given how exquisitely fine-tuned our universe is, it must be the product of intelligent design.

We purposely chose this last postulate because it gives us much more room to let our imaginations run wild as to what form this intelligent design takes, is this a Supreme Being in the classical sense of God, does time exist for God, what was God doing before he created the universe and what is He doing now. Along the way we rejected two other possibilities, one suggested by Isaac Asimov that this universe is the creation of a super-computer created by another civilization; and the String Theory variant of that that we are all simulations in a highly evolved Farmville game being run by a seventh-grader somewhere.

So, where we are is with the proposition that a Supreme Being, God, created this universe. The Big Bang is consistent with Genesis. What does that mean for us?

First of all, it gives real problems to the evolutionists. Evolution takes a similar tack as String Theory. Over time, given so many variants in organisms, we evolved. Evolution has no need for God, just as LaPlace had no need in his theory. But if God created this universe for us, doesn’t it make sense that He also placed animals, plants, microbes and all other forms of life here as well? If evolution is going to stand on the proposition that God isn’t necessary for life to have developed on Earth then it better explain the existence of the universe in the first place.

With the almost certainty of further offending anyone other than a physicist, I’ll close this post with one of my favorite quotations

on science. This is from Ernest Rutherford:   File:Ernest Rutherford cropped.jpg

                       All science is either physics or stamp collecting.

By this he meant that every other science is simply concerned with categorizing information.

What is Stuff Made Of?

The Standard Model starts out with this simple question: what is stuff made of?  Until about 100 years ago the answer would have been “atoms.”  The very word atom comes from a Greek word meaning “indivisible.”  Scientists thought atoms were the solid building blocks from which everything else was made.  Ernest Rutherford and others showed that atoms are mostly empty space.  There was a dense nucleus made up of protons (positive electric charge) and neutrons (neutral), surrounded by the cloud of negatively charged electrons.  For a time protons, neutrons and electrons were considered fundamental particles, indivisible any further.  Then in the 1960s “atom smashers,” machines that accelerate particles to extremely high speeds and smash them into each other, showed that protons and neutrons were composed of partially charged particles called quarks.  There was also a weightless particle called a neutrino that could pass through thousands of miles of solid iron without slowing down.  But things were still fairly simple.  There were quarks, electrons and neutrinos. Quarks are incredibly tiny.  If an atom was the size of the Earth, a proton would be a football stadium and a quark would be a tennis ball.

In the next decade, more powerful particle accelerators, capable of accelerating particles to near light speed, demonstrated hundreds of fundamental particles.  All seemed to fall into one of 12 categories of fermions, depending on their mass.  The lowest level of fermions contains normal matter:  up and down quarks, electrons and neutrinos.  The next two levels contain fermions that exist only fleetingly in particle accelerators.  Each of the 12 fermions has a corresponding antiparticle that can only be created with a sufficiently energetic collision.

English: Standard model of elementary particle...

English: Standard model of elementary particles: the 12 fundamental fermions and 4 fundamental bosons. Please note that the masses of certain particles are subject to periodic reevaluation by the scientific community. The values currently reflected in this graphic are as of 2008 and may have been adjusted since. For the latest consensus, please visit the Particle Data Group website linked below. (Photo credit: Wikipedia)

As a counterpart to fermions there are four bosons that carry all forms of energy.  Photons carry electromagnetic energy (light and all other wavelengths of electromagnetic radiation). W and Z bosons carry the weak force, which gives rise to radioactivity; and the strong force that binds atomic nuclei together.  Finally there is the hypothetical graviton that carries the force of gravity.  The graviton has never been observed.

The theoretical framework that describes the 12 fermions and four bosons is called the Standard Model. The Standard Model does for particle physics what Newtonian physics first did for the observable world (the world we live in) and General Relativity did for the cosmos. It explains what we see. The Standard Model predicts that the four fundamental forces, which vary greatly in their strength, will be unified at sufficiently high energy. This prediction was partially proven in the 1970s when the electromagnetic and weak forces were unified. Like Newtonian physics and General Relativity, the Standard Model is incomplete. It fails to explain why there are three levels of quarks and light particles. It leaves open the possibility that quarks may be further divisible. For a time scientists theorized another boson called the Higgs boson that gives all other particles their mass in order to preserve the Standard Model.  In July 2012 scientists using the Large Hadron Collider at CERN discovered the Higgs boson. This gave a huge boost to the Standard Model, which some felt had outlived its usefulness.

Why is this important to us? Let’s revisit the Big Bang. One millionth of a second after the explosion the universe is about the size of our solar system and is as dense as air. It’s 10,000 times hotter than the core of the sun. Particles and antiparticles appear, collide and annihilate each other at a staggering rate. By ten millionths of a second after the Big Bang expansion has cooled the universe to the point that particles and antiparticles can no longer form from the radiation. The number of particles and antiparticles is fixed and they begin a war of mutual extermination. By 100 microseconds, a twentieth of the time it takes a bee to flap its wings, it’s all over. All the particles and antiparticles have paired up like guys and gals at a dance. There are no wallflowers. All matter is extinguished and the universe contains only radiation.

But wait, you say. That would be the “nothing” universe and we already know there is “something” because we’re here to wonder how it all began. And you would be right. For some unknown reason the symmetry between matter and antimatter wasn’t perfect. It was off by one part in a billion. For every billion antiparticles there were a billion and one particles. When the last particle of antimatter paired with a particle of matter there were a billion photons for every particle left, and no antiparticles. The photons continued to spread out to be discovered billions of years later as cosmic microwave background radiation and the remaining particles combined under the force of gravity to become 100 billion galaxies, one of which contains a very ordinary star around which eight planets revolve, one of which we call home.

How big is one part in a billion? Imagine someone has laid out pennies over an area three miles on a side. All pennies show heads except one. That one penny showing tails is the one particle of matter left after the billion pennies showing heads were annihilated by another billion pennies showing tails.  It’s from those leftover tails that the universe is made.

The Time has Come

The metric expansion of space. The inflationar...

The metric expansion of space. The inflationary epoch is the expansion of the metric tensor at left. (Photo credit: Wikipedia)

The time has come, I tell you now, to speak of many things.

Of matter dark and giant bangs and theories made of strings.

And how the universe began and what the future brings.

Physics has settled on the theory as to how the universe came to be, which it named The Big Bang Theory.  The theory isn’t without warts.  Remember that the Big Bang predicts a universe that is younger than the planets and stars it contains.  Another unanswered question is why was it so hot right after the Big Bang?  A third question is why is the universe so uniform on a large scale?  Even with billions of stars and galaxies clumped together in local regions, on a very large scale the universe is quite uniform.  Another significant question is why is the rate of expansion so finely tuned?  If the rate of expansion of the universe had been smaller by one part in 1015 just one second after the Big Bang, gravity would have overcome expansion and the universe would have collapsed on itself by now.  Had it been about that much greater, gravity wouldn’t have had a chance to accrete matter to form into stars, galaxies and planets.

We’ve noted several times that the Big Bang Theory smacks of a creator, or intelligent design.  The last question, why is the universe so finely tuned, feeds that notion.  We live in a Goldilocks universe, not too big, not too small, but just right.  Why is that so?  What are the odds of that happening in the absence of some benevolent outside influence?

The way science has responded to these questions is interesting, to say the least.  Consider the Big Bang itself.  How did that happen?  Doesn’t the description in an earlier post of what the Big Bang looked like sound an awful lot like Genesis 1:3 in the Bible?  Can science explain what caused the Big Bang so as to eliminate an outside influence?  One explanation that has been posited is one of Alexander Friedman’s models.  Remember that Friedman said that three possibilities exist for an expanding universe.  The first is that it expands continually at a fairly steady rate.  The second is that it expands continually at an ever-decreasing rate, but never actually stops and contracts.  The third is that the universe goes through cycles of expansion and contraction.  The end of each contractive phase ends in a Big Crunch as all matter collapses in on itself.  This in turn causes another Big Bang.  It’s much like a Slinky going down an endless flight of stairs.  The Slinky expands and pulls itself over the first step then contracts as it hits the second step.  Then it bounces and expands itself over the second step.  This explanation only solves the problem for our particular expansive stage of the Slinky universe.  The question still remains, who or what pushed the Slinky off the top step?

Physics describes the universe by means of two partial theories, general relativity and quantum mechanics, neither of which can fully explain the current universe that we observe, and each of which, alone, give contradictory predictions.  General relativity breaks down as we work backwards.  With all matter squeezed into what scientists call a singularity, general relativity is inadequate for the task.  At that point we have to look at the opposite spectrum of physics, particle physics, the science of particles, the things that make up atoms .  When we enter that realm, we leave the certainty of the real world behind.  Nothing is at it seems.

Stay with us; things are about to get very weird.

Lemaitre Sheds Light and Creates Conflict

Georges Lemaitre was born in 1894.  He began studying engineering but, like Friedmann, his studies were interrupted by World War I.  In the trenches he observed first-hand the effects of German mustard gas and won the Croix de Guerre.  After the war he returned to his studies but switched to theoretical physics.  He also enrolled in the seminary and was ordained a priest in 1923.  For the remainder of his life he pursued two careers, physics and the priesthood, saying “There were two ways of arriving at the truth.  I decided to follow them both.”

Georges Lemaître is credited with proposing th...

Georges Lemaître is credited with proposing the Big Bang theory of the origin of the universe in 1927. (Photo credit: Wikipedia)

In 1923 after spending two years in Cambridge with Arthur Eddington, Lemaitre returned to Belgium and began his own cosmological quest for truth.  He adopted Einstein’s general relativity but, like Friedmann, rejected the notion of the cosmological constant.  Without knowing anything about Friedmann’s work, Lemaitre resurrected the expanding universe model.  Unlike Friedmann who was a mathematician, interested mainly in the numbers of the theory, Lemaitre wanted to understand the reality behind the numbers.  If the cosmos were expanding, Lemaitre decided to run the clock backwards.  An expanding universe implied that things were closer together yesterday, closer still 100 years ago and still closer 1 million years ago.  Run the clock backward enough and the inescapable conclusion was that everything was together at one point.

Perhaps influenced by his theological training, Lemaitre realized that general relativity implied a moment of creation.  He concluded that the universe began in a relatively small, compact region that suddenly expanded and evolved into what we observe today.  He refined his theory into what he called the primeval atom that contained all of the matter that eventually became the stars and planets.  Though a moment of creation was central to his theory, Lemaitre was interested in the evolution of the universe from the primeval atom to the stars and galaxies.

Lemaitre published his theory and was met with the same deafening silence that greeted Friedmann.  To make matters worse, Lemaitre also had a run-in with Einstein who rebuffed him, saying that his mathematics were correct but his “physics is abominable.”  Einstein had thus been offered two chances to accept an alternative to the steady state view of the universe and rejected both.  As the world authority on cosmology, Einstein’s words had the force of law.  It is ironic that, having challenged authority in his early career Einstein had now become the authority behind whom virtually all scientists fell into line.  It probably didn’t help Lemaitre that he was a priest and his theory smacked of a Creator.  Though it had been nearly four centuries since Galileo was forced to confess, the wounds science felt from religion were still tender.

The truth is, both theories were appealing and both had flaws.  The flaw in the steady state theory was the cosmological constant, which, as we have seen, is nothing but a fudge factor to make the theory conform to the accepted view of how things are.  The flaw in the nascent big bang theory (it still had not been thus named) was that there was no evidence to support the theory of a sudden explosion, other than the logic behind an expanding universe.  For that matter, though, there was no evidence to support a steady state model other than the belief that this is how things are.  The theorists needed evidence to support their various theories so they turned to the experimental physicists, the astronomers.

Friedmann’s Models of the Universe

Alexander Friedmann was a brilliant mathematician who also had a penchant for science and technology.  After enduring both the First World War and the Russian revolution in 1917, Friedmann was eventually introduced to Einstein’s Theory of General Relativity.  It may have been a combination of his delayed exposure to the theory and Russia’s relative isolation from the rest of the world that allowed Friedmann to ignore Einstein’s (and most other physicists’) view of the universe as static and formulate an entirely new and radical approach.

While Einstein started with the assumption that the universe is static and introduced the cosmological constant to counter the effect of gravity, which, under his view, would eventually lead to the collapse of the universe, Friedmann ignored the cosmological constant and then looked at general relativity to see what kind of universe it predicted.  First of all, Friedmann’s model was one of a dynamic universe, one that had started with an initial expansion (the term Big Bang wouldn’t come along for some 30 years).  This initial expansion led to three possible results:

friedmann models

friedmann models (Photo credit: Wikipedia)

First, if the initial expansion wasn’t great enough, gravity would eventually pull the universe back in on itself.  Like a ball thrown upward, the universe would at first move quickly, then slow to a complete and brief (in cosmological terms) time, and then begin to contract ever faster.  Friedmann envisioned it then expanding again, endlessly like a bouncing ball.

Secondly, if the initial expansion was great enough, the universe would continue to expand infinitely.

The third view was a middle ground in which the initial expansion was enough so that the universe would continue to expand, though slower and slower, never quite stopping.  It is like the problem of the rabbit and the lettuce.  Each second a rabbit moves one-half of the remaining distance between himself and a piece of lettuce.  For example, the rabbit starts out four feet from the lettuce.  In the first second he moves two feet closer.  The second second he moves one foot closer.  The third second he moves six inches closer and so forth.  Does he ever reach the lettuce?  The answer is, no, he never covers the remaining half-distance to the lettuce.  Similarly Friedmann’s third model never quite reaches a point where gravity overcomes expansion, though the rate of expansion continually slows until, like the rabbit, the universe is creeping forward.

Friedmann thus proposed a model of the universe based on general relativity that did not match the model proposed by the creator of the Theory of General Relativity, Albert Einstein.  Although Einstein would admit that Friedmann’s view was mathematically correct based on general relativity, he claimed it was scientifically irrelevant because the universe was static.

Friedmann was eventually proven correct, but he did not live to see himself vindicated as Einstein had done with his theory.  Friedmann died of a serious illness, probably typhoid fever, in a delirium, reportedly lecturing to an imaginary audience.  Part of Friedmann’s problem was that his notion was too radical.  He suffered the same fate as Copernicus in that the scientific world simply wasn’t ready for his view of the universe.  Another problem was that he locked horns with Einstein himself, the world’s foremost cosmologist at the time.  Finally, Friedmann, a mathematician, was not an astronomer and was therefore an outsider to the cosmological world.  Though Friedmann’s papers were published during his lifetime they received almost no notice and would not until they were rediscovered by a Belgian scientist, Georges Lemaitre.

The Cosmological Consequences of General Relativity

In 1917 Einstein published a paper entitled Cosmological Considerations of the General Theory of Relativity. The title is significant.  Unlike Galileo, Copernicus, Kepler, Brahe and Newton, Einstein was concerned with the entire universe, not just the solar system.  Calculating the orbit of Mercury to predict its movement around the sun was hard enough, but Einstein had the audacity to attempt to predict the movement of stars and galaxies.  In order to do this he had to make an assumption.  His assumption, known as the cosmological principle, is that the universe is isotropic and homogeneous.  This means that the universe looks pretty much the same in every direction, and that it looks that way from whatever vantage point in the universe you have.  This means that we do not occupy a special place in the universe.

When he applied his theory to the universe, the result was unsettling to say the least.  General relativity predicted that the universe was destined to crash in on itself as a result of gravity’s relentless pull on the stars and galaxies.  Newton’s theory had predicted the same thing.  In the early 20th Century, the view of the universe was that it was stable, that it had always existed more or less as it is today.  But Einstein’s prediction was that things would start creeping slowly toward each other.  The creep would turn into a frantic dash as stars and galaxies collided.

Anxious to make general relativity consistent with the observed and accepted notion of what the universe is, Einstein realized that if he introduced a constant, which he called the cosmological constant into general relativity, he could keep the result from being a huge crunch at some point in the future.  The cosmological constant was a sort of anti-gravity that repelled matter, offsetting the natural attraction of gravity just enough to prevent collapse.  It was, in essence, a fudge factor similar to that found by proponents of Newton’s theory of gravity who were unwilling to accept general relativity.  Even Einstein was somewhat ashamed of the need for this fudge factor, saying that it was “detrimental to the formal beauty of the theory [general relativity].”

Most scientists were content to accept the cosmological constant as a “refinement” to general relativity because it made the theory fit with their notion of the universe.  Remember we began with the adage that things are what they are and if the theory doesn’t explain them we better get a new theory.  No one wanted to jettison general relativity after having just adopted it.

No one, that is, except Alexander Friedmann, a Russian scientist born in 1888.  Friedmann would tackle orthodoxy head on and come up with a radically different view of the universe, one that would not be confirmed for decades.

Einstein’s Victory

Einstein needed to be able to predict a result that hadn’t been observed yet.  Only in this way could he definitively show the superiority of his theory over Newton’s.  Think of it this way:  Suppose you have been talking to two investment advisers, Fred and Barney.  Fred shows you his calculations that predicted yesterday what the stock market did today.  Barney shows you his calculations today that predict what the market will do tomorrow.  Tomorrow the market performs exactly as Barney predicted.  Whom do you believe?  Fred could have manipulated his theory to match today’s results because he knew the result before he gave you his prediction.  But Barney couldn’t have known what the market would do today except through his theory.

Einstein had long pondered the relationship between light and gravity.  Since the General Theory of Relativity defines gravity as a warp in the fabric of spacetime and light travels through spacetime, under Einstein’s theory light should be affected by a massive body such as the sun.  Einstein theorized that light from a star behind the sun would be bent, resulting in an apparent shift in its position.  The problem was, you can’t see any stars when the sun is shining.  Einstein realized that during a total solar eclipse stars are visible in the daytime sky so he looked for an opportunity and an astronomer (remember, Einstein was a theoretical physicist — he didn’t actually conduct experiments) to observe stars during a solar eclipse.  He found both a partner in Arthur Eddington and an opportunity in the Southern Hemisphere in 1919.  Eddington and one team went to the island of Principe off West Africa and another team went to Brazil, hoping that if clouds obscured the eclipse in one location, the other location would be clear.

Eddington's photograph of a solar eclipse, whi...

Eddington’s photograph of a solar eclipse, which confirmed Einstein’s theory that light “bends”. (Photo credit: Wikipedia)

In the end both teams were successful in observing the eclipse and taking what photographs needed to be taken.  After developing the plates, making measurements and calculating margins of error, Einstein’s predictions were within the margin of error while the results predicted by Newton’s laws were far too low.  Both Eddington and Einstein became virtual rock stars in science.  Eddington became inextricably connected to general relativity.  At one point someone said to him that he was one of three people in the world who understood the General Theory of Relativity.  Eddington was silent for several seconds and finally the person urged him not to be so modest.  “On the contrary,” Eddington replied, “I am trying to think who the third person is.”

The vindication of Einstein’s theory required a paradigm shift, a complete and sudden alteration in the way science viewed the universe.  Science usually moves incrementally, in small changes.  It isn’t often that Saul becomes Paul on the road to Damascus.  When a paradigm shift such as this occurs it usually isn’t generally accepted.  Older scientists who have devoted their professional lives to a particular view of things are reluctant to change and often it requires a dying off of the older generation before a new theory is completely accepted.  Such was the case with the General Theory of Relativity.  Yet his theories have been proven correct.  Einstein was once asked by a student how he would have felt if the universe had ultimately turned out to be different than his theory predicted.  With tongue firmly in cheek he replied, “Then I would feel sorry for the Good Lord.  The theory is correct anyway.”