Wednesday, December 7, 2011

fabricating reality

when science, reality and the mind fall apart...
This is the 5-minute talk I gave at Ingnite Zurich.

(Here you can find a written version of the ideas considered here: On Certainty...)

slide 1

Russell's complete quote:
One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision.

Similar sentiment from Daniel Kahneman, Thinking Fast and Slow, 2011, pg. 201:
Our comforting conviction that the world makes sense rests on a secure foundation: our almost unlimited ability to ignore our ignorance.

slide 2

Crazy technology:
Watch Juan Enriquez' TED talk: Tech evolution will eclipse the financial crisis

You get the idea;-)

slide 4

The Standard Model of particle physics and General Relativity are the two most accurately tested theories around.

For more information on the diagram, see Appendix A.2.2 here.

slide 5

String theory, i.e., the collection of the five known superstring theories, had its heyday around 1995, when Edward Witten unified the framework and introduced M-theory. It posits that the fundamental building-blocks of reality are extended entities: strings or membranes. For the mathematics to work, reality has to be 11 dimensional, that is, 10 spacial dimensions plus time. It also requires a new symmetry of nature, called supersymmetry.

In the last decade however, there has arguably not been a lot of excitement in the field. The biggest problem being the missing experimental predictability of the theory. This perhaps explains why Witten recently was on sabbatical at CERN, where the LHC is hoped to give glimpses of supersymmetry or extended dimensions.

An other effort to unify quantum mechanics with general relativity is Loop Quantum Gravity, which does not need a higher-dimensional reality with supersymmetry.

slide 6

Here a list of all the fundamental questions I can think of;-)
A Few Questions... 
And: What Can We Know?

The Higgs particle was needed for a peculiar reason. All the equations of the Standard Model don't work if terms for the mass of particles are introduced. Technically, the SU(3)xSU(2)xU(1) invariant Lagrangian, describing massless particles, can incorporate mass terms via, what is known as, the Higgs mechanism.

Although being a mathematical trick, it is associated with a physical particle. It is a cornerstone of the Standard Model, however, there is no real sign of it at the LHC.

Personally, I do not believe that the particle exists, as I have my personal crackpot theory. Here in a nutshell and here in detail;-)
Edit: on the 4th of July 2012 a Higgs-like boson was found in CERN's LHC particle accelerator (both CMS and ATLAS detectors) around 125-126 GeV (5 sigma level). However, they stress "the results presented today are labelled preliminary" and "positive identification of the new particle’s characteristics will take considerable time and data.". More on the coming challenges here.

slide 7

For more information on the diagram, see Appendix A.2.1 here.

Gödels's life ended tragically, as he drifted off into insanity. Watch BBC Four's documentary Dangerous Knowledge. Or watch this.

slide 8

For more on the philosophy of science, see Appendix A and A.1 here. And more in What are Laws of Nature? and A Philosophy of Science Primer.

What the Tortoise Said to Achilles, written by Lewis Carroll, is a brief dialogue about the problematic foundations of logic.

A very interesting book on this is Zen and the Art of Motorcycle Maintenance by Robert Pirsig.

Finally, What is a "Law of Physics", Anyway? And look it up in the Stanford Encyclopedia of Philosophy: Laws of Nature.

slide 9

Einstein's complete quote:
The supreme task of the physicist is to arrive at those universal elementary laws from which the cosmos can be built up by pure deduction. There is no logical path to these laws; only intuition, resting on sympathetic understanding of experience, can reach them.

Eugene Wigner, in his essay The Unreasonable Effectiveness of Mathematics in the Natural Sciences,says:
  • […] the enormous usefulness of mathematics in the natural sciences is something bordering on the mysterious and […] there is no rational explanation for it
  • […] it is not at all natural that “laws of nature” exist, much less that man is able to discover them
  • […] the two miracles of the existence of laws of nature and of the human mind’s capacity to divine them
  • […] fundamentally, we do not know why our theories work so well

More Einstein:
The most incomprehensible thing about the world is that it is comprehensible.  
The fact that it is comprehensible is a miracle.

slide 10

Thomas Kuhn's influential work on the history of science and its many paradigm shifts and revolutions prompted Max Planck to say:
A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

Steven Weinberg's full quote in this context:
If the transition from one paradigm to another cannot be judged by any external standard, then perhaps it is culture rather than nature that dictates the content of scientific theories.

The influential philosopher of science, Paul Feyerabend, claimed that there is no such thing as scientific method. "Anything goes!", he said.

The term postmodernism is hard to define briefly. It has been around for a hundred years or so. In a historical context, Richard Tarnas' book The Passion of the Western Mind, summarizes the last 3000 years (or so) as:

The Greek world view → the Christian world view → the transformation of the medieval era → the modern world view (Renaissance, Reformation, Scientific Revolution) → the transformation of the modern era (the crisis of modern science, existentialism and nihilism).

Finally, the last chapter: the Postmodern Mind reads:
There is an appreciation of the plasticity and constant change of reality and knowledge, a stress on the priority of concrete experience over fixed abstract principles, and a conviction that no single a priori thought system should govern belief or investigation. It is recognized that human knowledge is subjectively determined by a multitude of factors; that objective essences, or things-in-themselves, are neither accessible nor possible; and that the value of all truths and assumptions must be continually subjected to direct testing. The critical search for truth is constrained to be tolerant of ambiguity and pluralism, and its outcome will necessarily be knowledge that is relative and fallible rather than absolute or certain.

Postmodernism in real life: Sarah Kay's TED talk If I should have a daughter is about making a list of 10 things you know to be true and comparing it with enough other people's list, and finding that:
  • someone has the exact same, or very similar, thing as something on your list (affirmation)
  • someone has the complete and total opposite to something you know is true (dissonance)
  • someone has something you have never even heard of before (novel thoughts)
  • someone has something you thought you knew everything about, but they are  introducing a new angle to look at it (limited scope)
Aldous Huxley once answered an interview question about who should try LSD with:
Well I think the people who would benefit most of all are professors. I think it would be extremely good for almost anybody with fixed ideas and with a great certainty about what's what to take this thing and to realize the world he's constructed is by no means the only world. That there are these extraordinary other types of universe.

slide 12

Richard Feynman once said about quantum mechanics:
For those who are not shocked when they first come across quantum theory cannot possibly have understood it. 
I think I can safely say that nobody understands quantum mechanics. 
And to quote Niels Bohr:
If quantum mechanics hasn't profoundly shocked you, you haven't understood it yet.
And there is some more craziness: Quantum probability, the measurement problem, tunneling, vacuum fluctuations, Wheeler's delayed choice experiment, quantum teleportation, the no-cloning theorem and on and on...

Recently, a triple-slit experiment was done. And note that things like entanglement and wave-particle duality have been measured for objects as big as a buckyball.

Most alarming are experiments apparently violating causality: delayed-choice entanglement swapping, or the experiment discussed at the end of the next section.

The many-worlds interpretation of quantum mechanics says there are an infinite amount of parallel realities. Everything that could possibly have happened in our past, but did not, has occurred in the past of some other universe or universes.  (From Wikipedia.)

See also David Deutsch's Fabric of Reality. Or watch his TED talk: What is our place in the cosmos?

slide 13

Special Relativity comes from the fact that light has a constant speed. One of the consequences, next to time dilation, is Einstein's famous equation stating the equivalence of mass and energy.

Current estimates are that the universe is 70% dark energy, 25% dark matter, and only 5% of it is visible matter or normal energy. Unfortunately, we have no real idea what 95% of the universe is actually made up of. The 2011 physics Nobel prize was awarded for the observation that the expansion of the universe since the big bang is accelerating. This is thought to be due to dark energy, which basically is an energy content of the vacuum.

Regarding the fine-tuning of the universe, the anthropic principle argues that observations of the physical universe must be compatible with the conscious life that observes it. The idea of a multiverse, for instance the many worlds interpretation of quantum theory or coming from M-theory, easily explains fine-tuning: Of the many parallel universes we obviously live in the one where the fundamental constants have the values we measure.

And there is more:
  • Arrow of time: Why was the universe initially in such an ordered (low entropy) state?
  • What is the nature of time? There is no theory explaining it.
  • Is the universe finite or infinite?
Watch Sean Caroll's TED talk: Distant time and the hint of a multiverse

Get a feeling of the involved scales of the universe. And the time spans: David Christian's TED talk, Big history, which brings you from the Big Bang to the Internet, in 18 minutes.

However, things get truly bizarre when the quantum theory is merged with relativity: experiments have shown that causality falls apart. It's impossible to tell what is the affecter and what is being affected. Concepts of before and after make no sens. There is no real time in the quantum world. And is time an illusion?

slide 14

 The limits of physics:
  • Closed-form solutions to analytical equations are mostly only attainable if non-linear effects (e.g., friction) are ignored; most physical systems in nature are non-linear
  • Not too many interacting entities can be considered (e.g., the three body problem: the equations describing three gravitating bodies cannot be solved - there are an estimated 100 billion galaxies in the universe)
The paradigms of complex systems:
  • Every complex system is reduced to a set of objects and a set of functions between the objects 
  • Macroscopic complexity is the result of simple rules of interaction at the micro level
The first paradigm says that networks are ideal representations of complex systems. The second one is mysterious: complexity comes from simple rules of interaction. This allows complex systems to be easily simulated in a computer, e.g., agent-based simulations. Or Stephen Wolfram's cellular automaton rule 110, which results in a pattern that is neither completely random nor completely repetitive. And John Conway's Game of Life. Fractals, like the Mandelbrot set, are defined by a very simple iterative equation, however, yielding a visualization that can be zoomed into endlessly, revealing an amazing amount of complexity and miniature versions of the original set (self-similarity). Finally, multi-scale Turing patterns are reminiscent of biological structures.

Wolfram also noted:
[The] results [that simple rules give rise to complex behavior] were so surprising and dramatic that as I gradually came to understand them, they forced me to change my whole view of science […].

It took me more than a decade to come to terms with this result, and to realize just how fundamental and far-reaching its consequences are.

Watch Wolfram's TED talk: Computing a theory of everything.

Complex systems in a nutshell: Chapter 1 here. Scaling laws are relevant when it comes to regularities in complex systems.

In closing: science, an overview, and in a nutshell

slide 15

David Eagleman on perception:

You're not perceiving what's out there. You're perceiving whatever your brain tells you.

We do not see with our eyes but rather with our brains.

Waking perception is something like dreaming with a little more commitment to what's in front of you.

What we call normal perception does not really differ from hallucinations, except that the latter are not anchored by external input.

You're perceptual world always lags behind the real world.

What you are able to experience is completely limited by your biology.

Our brains sample just a small bit of the surrounding physical world.

This is all why we would never "stop to think that there is more beyond what we can sense."

Instead of reality being passively recorded by the brain, it is actively constructed by it.

There are thoughts you cannot think.

The exact levels of dozens of neurotransmitters are critical for who you believe yourself to be.
From here.

And consider things like selective attention, synaesthesia and the McGurk effect.

slide 16

David Eagleman on  the "conscious me":
Our brain runs mostly on autopilot, and the conscious mind has little access to the giant and mysterious factory that runs below it.

The conscious mind is not at the center of the action in the brain; instead it is far out on a distant edge, hearing but whispers of the activity.

The unexpected part of the news is that the conscious you is the smallest bit-player in the brain.

Almost all of our actions are run by alien subroutines, also known as zombie systems.

We are constantly fabricating and telling stories about the alien processes running under the hood.

Fabrication of stories is one of the key businesses in which our brain engages.

Consciousness seems to be about setting goals for what should be burned into the circuitry, and it does little beyond that.

Again from here.

People have been suggesting that the self is constructed and doesn't really exist. For instance Tomas Metzinger. Or watch Henry Markram's TED talk, Supercomputing the brain's secrets:
This theory [of the brain] is that the brain creates, builds, a version of the universe and projects this version of the universe like a bubble all around us.

Experiments have been showing, that the ongoing experience of being located inside our bodies can be modified: If I Were You: Perceptual Illusion of Body Swapping. This started with the classic experiment Rubber hands "feel" touch that eyes see, from 1998.

And what about life anyway? And, for that matter, death? For instance on death and dying.

slide 17

Behavioral economics:
More on happiness from Dan Gilbert (here and here) and Matthieu Ricard.

Tasting the same wine three times, but experiencing more pleasure if you thought it was expensive: Marketing actions can modulate neural representations of experienced pleasantness.

Feeling pain depends on what your beliefs are about the current experience: Paul Bloom's TED talk: The origins of pleasure.

Molly Crockett's TED talk: Drugs and morals and Paul Zak's: Trust, morality - and oxytocin.

And on and on:
Recently someone posted a sign, reading: Don't believe everything you think.

slide 18

The outlook, that no matter how strongly I believe something, no matter how fiercely I am willing to defend my belief, it still simply could be wrong, gives me the incentive to be open. Open-minded and open towards other people. I believe that the world is currently seriously lacking this attitude.

On being wrong:
Alan Alexander Milne in Winnie-The-Pooh. The House at Pooh Corner:
"Rabbit's clever," said Pooh thoughtfully.
"Yes," said Piglet, "Rabbit's clever."
"And he has Brain."
"Yes," said Piglet, "Rabbit has Brain."
There was a long silence.
"I suppose," said Pooh, "that's why he never understands anything."

Personally I try not to exclude much about the workings of reality. Even taboo subjects relating to psi phenomenon: Rupert Sheldrake and Dean Radin.

slide 19

Rolf Landauer's erasure principle.

Seth Lloyd's original quote from his book Programming the Universe:
[It can be shown] that quantum computers can simulate any system that obeys the known laws of physics in a straightforward and efficient way. In fact, the universe is indistinguishable from a quantum computer.

And see more in Charles Seife's book, Decoding the Universe. Information theory, especially quantum information, appears to be the most fundamental aspect of reality. Relativity is essentially about the transmission of information. Quantum theory is at heart about extracting information from reality: the information you receive depends on how you gather that information.

Information is weird:
Digital physics is a collection of theoretical perspectives based on the premise that the universe is, at heart, describable by information, and is therefore computable. Therefore, the universe can be conceived as either the output of a computer program or as a vast, digital computation device (or, at least, mathematically isomorphic to such a device). (From Wikipedia.)

slide 20

The most relevant book I've read in a while: The Passion of the Western Mind by Richard Tarnas. See also the participatory theory. Or the subject-object problem.

Can consciousness fabricate reality? Could this be part of the key: If my life were a book and I were the author, how would I want the story to go?

Seriously, contemplating all of the above, I really cannot exclude anything about the nature of reality...


jbg said...

Mahzarin Banaji: Beyond Belief 2006

Implicit association (measuring unconscious biases):

jbg said...

more random stuff:

Dopamine levels in brain 'influence decision making'

Stanford Researchers Complete 1st Complete Computer Model of an Organism

jbg said...

Wired: Jellyfish Made From Rat Cells Swims Like the Real Thing

jbg said...

Ramesh Raskar: Imaging at a trillion frames per second