Reply To: T-shirt designers unite and take over

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Lerner wrote: See The Emperor’s New Clothes. ..It will be on our website http://www.cosmology.info very soon.

I had wanted to interact with Eric Lerner, author of BBNH, ever since I read the book the first time. I wanted to interact with Taleb after reading “The Black Swan” but that didn’t work out. Someone named “Lerner” posted the response I quoted above. I’ll behave as if that is the real Eric Lerner, because I still would like to engage in a back and forth discussion.

Note about a year ago I sent an email to Eric offering my services as a programmer in the focus fusion effort. I suggested using video graphics boards, say by NVIDIA, as computational resources. The focus fusion effort would perhaps be helped by doing complex simulations. While I don’t know enough math to assist, I had thought I could contribute programming services. I was also fired up to invest in the focus fusion effort.

Then the economy tanked. My portfolio fell by 50% and so I was no longer in a mood to invest, and put money at risk. I was scheduled to call Eric on a Monday, but I chickened out and never made the call. This is just by way of background. The concepts in BBNH come back to me upon occasion, and since I recently reread the book I’ve been thinking about related matters again. Sorry I’m so long winded…

There is a recurring theme which appears in BBNH regarding why is time only moving forward. Meaning since the laws of physics appear to function equally well forward or backward, why is there a direction of time. Eric you devote a lot of time to this question, and I’ve never understood why there is such a mystery. You cite the example of balls bouncing around on a billiard table, running a film backwards is just as believable as forwards, once the balls are in motion.

This is a convenient example that illustrates the problem of why time is one directional. But the example is a tiny subset of physical interactions that take place. Consider a box up on a shelf that tips over and falls to the ground. It is now in a lower energy state. This scenario is certainly not reversable. The box on the ground can no longer summon enough energy up to vault itself back up to the shelf. Things fall into lower energy states and are more stable. Things cannot enter higher energy states without some external source of energy.

Consider the lens of the human eye. The lens is made up of some transparent protein that can be deformed easily, so it can change its focus. The lens is formed in the womb along with the rest of the infant’s body. Upon entering the outside world, the lens is now subject to ultra violet radiation. Sometimes a UV light hits the lens in just the right way as to cause cross linking, or perhaps some damage to the lens protein itself. I’m unsure of the details. But suppose it is cross linking between two sulfur atoms in different protein layers of the lens. Suddenly this cross link exists and it’s a strong bond. Those layers can no longer slide relative to each other. The lens is no longer as pliable as it once was. The individual experiences trouble focusing the eye as well. And this is a typical manifestation of aging.

There is no mystery in this case why time proceeds in one direction only. The lens started out in a perfect, pristine state, then little by little acquired cross links and they persist. Once the sulfer atoms form their chemical bonds, they persist. They’re more stable than non-linked sulfur. QED. It’s like a lock snapping into place.

Or atomic nuclei bonding to form more stable nuclei, leading up to iron. Certainly each fusion is not reversable! At least without some external source of energy to break the bond.

Anyway I’ve never really understood why so much attention is placed on the question of why time is one direction only. Oh well.

Another point I wanted to make concerns the question of predictability. An argument is made that it is impossible to predict the future because space is infinitely divisible. One can never know exactly where all the particles are in order to model a system, because it would take infinite precision to even record the position of a single particle. And without knowing the exact positions, the errors will accumulate until the simulation will diverge from reality, inexorably, in increasing amount.

Why is it even a question? It feels like a sop to the religiously minded. They want the future to be uncertain. Free Will and all. Claiming that the universe can be deterministic in its principles, yet “we” can’t ever predict its outcome because we can’t ever get an accurate enough model of its current state — it sounds like a lame attempt to pacify religious people who wish that We Can Never Know The Mind of God. That is, writing out the physical laws of this universe would imply predictability and as such would imply that god himself is predictable, and as such is heresy. So in order to get past this obstacle (religious zealots that will sabotage efforts at achieving understanding) basically the assertion is, “Don’t worry — even if we do figure out the underying laws, we won’t be able to predict the future because we can’t know the current state accurately enough. You have nothing to fear!”

The truth is you don’t need space to be infinitely divisible in order to make it impossible to run the simulation into the future. Space could be quantized, it could take a finite amount of information to describe a particle’s position. Yet because we’re in the universe and every particle of the universe is interacting with every other particle, we can never be able to model the universe perfectly. CONT