Tuesday, April 23, 2013

The Beginning (with some updates to be friendly to all)



The beginning of the universe is a great story to tell, however, the history of how physicists found the current theory of the beginning of the universe is very interesting as well. Let’s add in another spice to this. Religions in general also said something about the beginning or non-beginning of the world. Being a Buddhist, I would like to see how well does Buddhism fair in this respect in light of the current cosmology.
Too often have I seen religious people trying to use science to support their own religion. That is until a scientist criticized that the theory of science that they are using is outdated or worse: misrepresented.


I hope not to fall into their company, but to be fair to both Physics and Buddhism, I shall attempt to present each field from their own point of view and not use one to prove or disprove the other. Yet, if I slip up somewhere, I’m sorry.


First we start with Buddhism, then the description about cosmology along with the comparison.


In Buddhism, there is this Kalama Sutta (AN 3.65) in which the Buddha told the people of Kalama village that there are ten specific sources which knowledge should not be immediately viewed as truthful without further investigation to avoid fallacies:
1.       by revelations,
2.       by traditions,
3.       by rumor, gossip, hearsay,
4.       by scriptures,
5.       by logical conjecture (alone),
6.       by it is a point of view or common sense,
7.       by having considered the reasons (philosophical dogmatism),
8.       by agreement with one’s own theories,
9.       by experts,
10.    by the thought “this monk is our teacher” (authority).
but when you know for yourselves that,
•       these qualities are skillful,
•       these qualities are blameless,
•       these qualities are praised by the wise,
•       these qualities, when adopted & carried out, lead to welfare & to happiness,
then you should enter & remain in them.
In science, theories must be verified and vetted by the experimental or observational data.

So you can see that Buddhism is much more interested in teaching the avoidance of evil, the doing of good and purification of mind. This is the central teachings of Buddhism. Why so? Because there is kamma and rebirth.

Take for example a quote from this sutta (SN 15.13):
From an inconceivable beginning comes transmigration. A beginning point is not evident, though beings hindered by ignorance and fettered by craving are transmigrating & wandering on.

Because beings undergo rebirth due to ignorance and craving, the central teaching is to recognize that there is suffering in life which is to be understood. And the cause of these suffering is due to ignorance and craving which is to be abandoned. The abandoning of the cause would lead to the end of suffering which is to be attained and the way to the end of suffering, morality, mental development and wisdom is to be developed. These are the Four Noble Truths in Buddhism, the first and central teachings of the Buddha.

True to its spirit of asking us not to just believe but to investigate, the Buddha repeatedly ask his disciples to practice meditation or mental development so as to be able to see into the workings of the mind and past lives to directly verify for ourselves the truth of kamma and rebirth. Before that, it remains a working hypothesis for those with faith to start on the journey.

So questions like "Is there a beginning?" is of no importance to Buddhism as the Buddha said that one would die before those things are answered, emphasizing that he is only interested in leading people towards the end of suffering, not philosophical questions.

Thus conventional wisdom in Buddhism would itself be enough for a Buddhist to not be bothered by the development of cosmology in Physics. However, as I am both a Physicist and a Buddhist, this is of some interest to me.

Specifically the problem is: If rebirth requires a physical universe for beings to be reborn into, then Buddhism requires a beginningless model of the Universe.

Now let’s look into the cosmology picture of the beginning.

In Physics, the idea that there was a beginning came about in a hard fight in the field of cosmology. In the early days, Einstein (and most people then) believed the Universe was static, contrary to what his equation of General Relativity says, he added a term called the cosmological constant to the equation to reflect his belief. Later Einstein admitted that the universe is not static due to observational data by Hubble. He called his modification of the equations of General Relativity his greatest blunder. After that there were two main schools of thought.

First was the steady state theory which says that the universe is infinite, and that the observation that it is expanding because it has always been expanding. The idea is that not only is the universe the same overall in space, but it is also the same in time! The constant density of the universe can be explained by matter spontaneously coming into existence so that the universe is always in this state, and therefore have no beginning.

Second is the now familiar big bang theory. It says that if the universe is expanding now, then it must have been in a state of very high density. Extrapolating back in time, we get the beginning of the universe when the density goes to infinity. The universe was of zero size. Currently the estimated figure is 13.8 billion years ago. The moment of the big bang is called the singularity, the ridiculous state of the universe where most laws of physics break down.

Now if this article, or dialogue between Buddhism and Physics were to occur at that time, then Buddhists most likely bet that further observations will eventually support the steady state theory. After all, the Buddha himself said that there is no way to conceive of a beginning.

The Buddhist point of view towards the beginning is that if there is a effect, there must be a cause. Tracing back to the cause, it is an effect of another cause. Repeating this formula, how could we have a first cause without something causing it to happen? [1]

In almost the same sense, this is the physics dilemma too with the big bang theory. Once you are at the singularity, what caused it to expand in the first place? What guarantees that all the laws of physics that comes after is conducive for a life bearing universe? [2]

I for one am glad that I wasn't an active engaged physicist Buddhist at that time. Or else I would have a great punch in the face to my faith when experimental evidence supports the big bang theory and the steady state theory has died down.

This story above tells us of the danger of trying to mix up science and religion, using science to support or to disprove religion.

When the big bang theory won out, physicists have been working on the details of almost every part of the evolution of the cosmos. Even up to now, the Large Hadron Collider (LHC) at CERN would be recreating the conditions near to the big bang and exploring the new physics there (the LHC would be restarting around 2015).

The singularity is the problem. Physicists haven't solved it yet because the largest problem so far is the combination of the 2 main pillars of modern physics: General Relativity and Quantum physics near the singularity. General Relativity is used when gravity is strong or cosmological scales are considered. Quantum physics is more at home with the behavior of nature at the very small scales. Both theories are incompatible in a fundamental level. Yet, near the singularity at the region called Plank scale where gravity is strong and the size is very small we must use a theory that combines General Relativity and Quantum Physics harmoniously. This is so that we can not only predict everything that happened up to the Plank scale, but also beyond it, where physicist are confident that the singularity from General Relativity will fade away in light of a more accurate model of the universe: Quantum Gravity. [3]

There are two possible contending Quantum Gravity theories currently popular and both of them predict a different scenario to replace the singularity. They are the
·         M-Theory, the 11 dimensional form that combined 5 string theories (everything is made up of strings of Plank length). M-theory contains branes (fundamental things that are more than just one dimensional) too. It is General Relativity in the language of Quantum.
·         Loop Quantum Gravity, that spacetime is made out of quantized loops; it is Quantum theory in the language of General Relativity.

To know how the universe began, we should look at how it could end. There were proposals of how the universe will end. One of the most symmetrical way for it to end is the natural combination of the big crunch plus the big bang, producing a big bounce. It requires that the universe is dense enough so that gravity will pull everything back together again in the reverse of the big bang into a big crunch. Then by some magic of Loop Quantum Gravity, after passing through the Plank scale, a super repulsive gravity is generated, hence the cause of a big bang can be explained, and there can be no beginning to the universe, or series of multiverses, separated in time.

It's a beautiful theory that can fit right into Buddhism. And if Buddhists happen to cling on to this idea, they will soon be disappointed as well because the theory of the infinite big bounce has a theoretical flaw.

There is sacred law in physics called the second law of thermodynamics. It states that entropy, the measure of disorder, always tend to increase in a closed system. Applied to the universe as a closed system, entropy does not get reversed during the phase of the big crunch. The arrow of time is still toward disorder. Eventually, with each new universe, the entropy will increase and makes the next cycles longer and bigger. As the previous cycles are shorter, there will be a beginning. Thus the multiverse in time idea is ok, but still has a beginning. However, stronger than this flaw is the observational data.

Data from 1998 cosmological observation suggests that the universe is not showing signs that it is slowing down, but rather it is accelerating out at an increasing rate. [4] This created the need for postulating dark energy (we called it dark because we have no idea what it is) as the source of this repulsive force. Eventually our universe most probably will die by the Big Rip, where everything expands out faster than the speed of light with respect to everything else, including the subatomic particles in our body. Thus a Big Crunch is not likely to be the end of our universe.

Now I’ll present three different possible theories of beginningless universe and a closed universe with a beginning in cosmology literature.

First, the inflationary universe theory is required to explain a number of observational data in the universe. According to it, the universe expanded faster than the speed of light for a while near the beginning and then stopped and expanded at the slower than the speed of light rate. Most inflation theories allows that some parts of the universe to keep on inflating while some other parts stop to create a universe. Ours could be one of them. Thus stretching this back to the past and to the future, we get an infinite series of multiverse with no need for a beginning and no end. In fact there’s a recent paper of possible observational data for this model. [5]

Second, the Baum-Frampton model gives an application of how a model of dark energy can lead to a sudden turnaround of a small patch of universe to a small volume just before the Big Rip. That patch will have its entropy reset (by throwing out most of the stuffs in the universe) and then inflation restarts the cycle, beginning the Big Bang all over again. This also produces more universes for each cycle. If there is an infinite amount of universe, then there would be no primordial (first) universe. [6]

Third, the Steinhardt-Turok model. This model is based on M-theory and assumes that our universe lives on a 4-dimensional brane (a fundamental object of the theory) that can collide with another universe of 4 dimensional brane in a higher dimension. Each brane is infinite in volume thus allowing for the accelerated expansion of the universe. In fact the expansion would clear the universe to vacuum again (solving the entropy problem) before gravity pulls two neighboring branes to another collision, producing the Big Bang. The collision would also explain away the things that standard cosmology uses inflation to explain. Since this cycle can repeat indefinitely, there is no beginning to this type of multiverse. [7]

Finally, in the book The Grand Design, the authors said that because there is a law such as gravity, the universe can and will create itself from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist. It is not necessary to invoke God to light the blue touch paper and set the universe going. [2]

However the discussion is far from ending in cosmology, reference [8] argues that there is a beginning for eternal inflation, cyclic evolution, and the emergent universe. Reference [9] replies that for all practical purposes, the universe is past eternal. This is because of the existence of future eternal universes. Imagine that time is like a real line in mathematics that starts from zero to positive infinity. We are like the people living far on the real line, even if the universe started at time zero, and we can’t see the zero. To us, there is practically no beginning!

In conclusion, for physics, the field of cosmology is far from dead, it’s just the beginning to gather more and more accurate data for precision cosmology.

From the side of Buddhism, there is no practical need to care about these models too. The best consistent model for Buddhism would be the Baum-Frampton model for predicting that the universe expands and contracts (there are other Buddhist texts that says the world expands and contracts), yet taking the lesson from the story above, I would not put down any money to bet that this model will ultimately win out amongst others. Who knows what’s the next top model in cosmology will be?

So, for Buddhist, the conclusion is the same as always. Paraphrasing Richard Feynman, shut up and meditate.

Bibliography


[1]Dalai Lama, The Universe in a single atom, United States of America: Morgan Road Books, 2005.
[2]S. Hawking and L. Mlodinow, The Grand Design, Bantam Books: United States of America, 2010.
[3]S. Hawking and R. Penrose, "The Singularities of Gravitational Collapse and Cosmology," Proc R Soc A, vol. 314, pp. 529-548, 1970.
[4]Riess, A. G. and others, "Observational evidence from supernovae for an accelerating universe and a cosmological constant," Astron.J., vol. 116, pp. 1009-1038, 1998.
[5]S. M. Feeney, M. C. Johnson, D. J. Mortlock and H. V. Peiris, "First Observational Tests of Eternal Inflation," Phys. Rev. Lett., vol. 107, no. 7, p. 071301, 2011.
[6]L. Baum and P. H. Frampton, "Turnaround in Cyclic Cosmology," Phys. Rev. Lett., vol. 98, no. 7, p. 071301, 2007.
[7]P. J. Steinhardt and N. Turok, "Cosmic evolution in a cyclic universe," Phys. Rev. D, vol. 65, no. 12, p. 126003, 2002.
[8]a. [hep-th], "arXiv:1204.4658".
[9]a. [hep-th], "arXiv:1204.5385".