[#19]  Teaching Reality: Starting with Gravity

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[#19] Teaching Reality: Starting with Gravity

In high school, students are taught 19th century physics, two centuries out of date.  Mechanics and gravitation appear as it was known in the late 17th century, and electricity and magnetism as it was known in the early 19th century.  This is a shame: it would be like teaching pre-Darwinian biology!

By Piet Hut

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[#18]  Singularities as Hints, Unrelated to Reality

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[#18] Singularities as Hints, Unrelated to Reality

Predictions of technological singularities are as wrong as predictions of singularities in physics, which have always been the harbingers of new physics.  When any prediction leads to division by zero, we can be sure that new laws or regularities will set in.  What singularities are good for is . . .

By Piet Hut

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Synopsis of Li Zhaoping's YHouse Luncheon Talk 11/9/2017

On Thursdays at noon Yhouse holds a lunch meeting at the Institute of Advanced Study, in Princeton. The format is a 15 minute informal talk by a speaker followed by a longer open-ended discussion among the participants, triggered by, but not necessarily confined to, the topic of the talk.  In order to share I am posting a synopsis of the weekly meetings.

Synopsis of Li Zhaoping’s Yhouse Luncheon talk 11/9/17

Presenter: Zhaoping Li (University College London)

Title: Looking And Seeing In Visual Functions Of The Brain

Abstract: "Vision is a window to the brain, and I will give a short introduction and demonstrate that it can be seen as mainly a problem of "looking and seeing", which are two separable processes in the brain.  Understanding vision requires both experimental and theoretical approaches, and to study the brain using our own brains have its peculiar difficulties."

Present: Piet Hut, Olaf Witkowski, Yuko Ishihara, Arpita Tripathi, Li Zhaoping, Michael Solomon

We made introductions. Arpita is new to the group and reported she worked in public health in India before recently moving to Princeton. Li Zhaoping studied physics in China before getting her PhD in Brain Science at Cal Tech and coming to the IAS 27 years ago as a post doc working then on the olfactory system. She currently works at University College London on vision, with an emphasis on computer science and on artificial and natural intelligence.

She began with the statement that “The Eyes are the window to the Brain.” Although the visual information pathway begins with the eye, in the monkey one half of the volume of the brain is for vision.  In humans one third of the brain is for vision. Piet asked, “How sure are we that these areas are not involved with other functions such as memory or thinking?”  If we place an electrode in an area of the brain and find that neuron responds to visual and not to auditory or other stimuli, then we attribute that area to vision. Higher animals devote more of the brain to vision.  Lower animals devote more to smell. Moving from the retina to the optic nerves from each eye, to the optic chiasma, we arrive at the subcortical center called V1 (visual one).  Signals then travel to the superior colliculus, the occipital cortex in the posterior part of the brain, and then the frontal lobes become involved.

     There have been some surprises in the study of vision.  In the 1960s at MIT Gerald Sussman (now a professor at MIT and someone Piet knows well) spent a summer project trying to learn how, with input of a picture of, e.g., a glass and a dinner plate, you could construct a computer algorithm that outputs “plate and glass”.  This is simple for humans to do, but not for computers.  The computer “sees” pixels and numbers, not a plate and glass.

    She showed two pictures of people boarding an airplane and asked us to tell what was different between the two.  Most identified that the plane engine was missing in one picture, but it took some time to identify that, contrary to our impression that we see all details of the picture with our first glance.  We are often blind to gross details.  In 1953 Stephen Kuffler showed that in the retina neurons see features of a center distinct from the immediate surroundings (like a target) and send these neural signals to V1.  If we put electrodes in the brain of an animal we can measure small activation potentials, in the order of 10 millivolts, when the animal is viewing an image on a screen. In the 1960s Hubel and Weisel studied V1 and found the neurons were not responding to image features – centers distinct from surround – that activate retinal neurons, but to small bars in the visual field.  Some of the neurons responded to vertical bars, some to horizontal, some to moving bars, some to color, etc. They received the Nobel Prize for their work.  In monkeys V1 is 12% of the neocortical volume.  Since that work, however, experimental   progress in understanding how V2, V3, or V4 work has not been as impressive. So, theorists are now looking at what happens in V1 and after. Somehow we gain object recognition and that recognition is rotationally invariant, i.e. we identify objects even when they are rotated in space.

     She showed a display of oblique lines in four rows, with one line the mirror image of all the rest (////\//).  It is relatively easy to pick out the different line.  When she showed a similar display of X shaped lines with one X different (⌿⌿⍀⌿⌿), it was more difficult to find the different one.  When she showed a display with 22 rows and 30 columns, it was much more difficult to find the different X.  In an early experiment, she followed the eye movement of subjects viewing the displays.  For most in their initial trials, the gaze travelled around the target within two seconds, then abandoned the target, and then returned.  She described this as “Looking” and “Seeing”. 

     In her model of vision, we begin with Input and then move -> to Encoding, then -> to Selection, and then to -> (and from <-) Decoding.  The Selection phase is Looking; the Decoding is Seeing.  Looking is Attention selection; Seeing is Recognition.  She drew the Chinese pictograms for Looking and Seeing and said these two characters mostly occur together in colloquial speaking. (See below at end of discussion.)  Piet pointed out that the pictogram for look has the hand in it.  The pictogram in Chinese for Look is the symbol for hand over the symbol for eye, as in hand palm down over eye for looking.  The pictogram for seeing is the symbol for eye over the symbol for son (or man), as in son of the eye.

     The human eye moves 3 times per second. The input from the retina is on the order of 20 frames per second, or about 20 megabytes/sec.  This is much too much to interpret.  Our attention bottleneck is about 40 bits/second, much less.  If 20 megabytes is about one large book, then 40 bits is about two sentences.  So, the brain chooses which 40 bits (two sentences) to focus on and deletes the rest.  Traditional wisdom assumes that this selection occurs in the frontal part of the human brain (Koch & Ullman 1985, and Treisman 1980s).  If the different bar is colored red, you see it right away.  In humans, the frontal lobes are about 29% of the brain, in monkeys 17%, and in dogs 12.5%.  For non-mammals, there is no frontal cortex.  She showed a video of a frog confronted with moving pictures of bugs.  The frog jumps at anything moving.  The frog has no V1 or V2. 

     According to her Saliency Hypothesis, V1 creates a bottom-up saliency map to guide looking or gaze shifts.  Hence, V2’s role should be seen in light of what V1 has done.  The frog has a superior colliculus but no neocortex.  In higher animals, the neocortex takes on the function of the superior colliculus and the superior colliculus shrinks dramatically.  In her theory, the primary visual cortex, i.e. V1, of primates, creates the saliency map and sends it to the superior colliculus which executes the map by shifting gaze to the most salient location.  She thinks that in lower animals the superior colliculus does both the saliency map creation and gaze shift execution. Piet asked if she was familiar with Rodney Brooks’ robots.  These are cockroach like robots with layers of computer inputs, where each layer focuses on a single aspect of the visual field, and the robot navigates without constructing a map of the field.  So, to see you must choose what to pay attention to.  Even though we move our eyes three times per second, we are only aware of a tiny fraction of that input, about 10 times/minute, and our brain deletes the data input not selected by attention (which shifts by gaze shifts).

     Piet noted that a similar model of focused attention is important in embodied cognition that Olaf is working on.  Perhaps they could collaborate on a paper on this topic.  Such interaction of different disciplines is just what Yhouse intends to promote.

     In V1 nearby neurons activated by similar features (e.g. vertical, horizontal, red, moving right, etc.) tend to suppress each other.  Hence a neuron responding to a vertical bar can have its response suppressed when there are other vertical bars nearby.  Piet quoted, “Neurons that wire together, fire together.”  Like-to-Like suppression occurs for vertical, horizontal, moving, or color reactive neurons.  We can measure this by measuring the firing rate for specific neurons in V1.  A map of this firing rates is sent to the superior colliculus, which shifts gaze to the location with the highest firing rate.  A surprising prediction that helps to prove this theory is that invisible features attract attention. She showed an example to illustrate this.  When different images are shown to the left and right eye, the brain combines them to provide a fused perception.  If you start with an image of a grid of lines that has all forward slash lines and one backwards slash line (/////\/////), and you create one image that is a copy of this image except for one forward slash missing (// //\/////) and show it to the left eye, and you create another image that contains only the missing forward slash (  /        ) and show it to the right eye,  then the fused perception is the summation of the left eye and right eye images and hence is the original image (/////\/////).  But when most people view this pair of images, their gaze moves first to the location of the forward slash in the right eye, even though they cannot tell the difference between this forward slash in the right eye from the other forward slashes in the left eye.  The invisible feature – which eye is the origin of the visual input - draws attention. That was one of her first published experiments and has since been replicated by other groups.  One of her present research projects involves measuring saccades, the series of small jerky movements of the eyes when changing focus from one point to another, to pop out targets in monkeys while measuring V1 neural responses.

     Olaf said he was surprised to find that neurons in vision behave like swarms of animals, like ants or honeybees.  He would not have expected similar algorithms to be at work for neurons for sight.  Specifically, the process is bottom-up.  An example is how birds flying in formation in a flock respond to avoid a predator.  There is no top-down communication from a lead bird indicating all turn this way.  That would be too slow, Instead, each bird moves in relation to a neighboring bird in the formation rapidly changing course to avoid the predator.  Zhauping asked if these birds have Like-to-Like suppressors? Olaf responded that he had not looked at that.  Each bird reacts to its neighbor just as each neuron reacts to its neighbor.

      Regarding top-down control, Michael asked if she was familiar with Anton Syndrome (also called Anton Babinski Syndrome).  This is a rare medical condition in which people who have suffered injuries resulting in loss of both the right and left occipital (visual) cortex, and are therefore blind, dramatically deny their blindness.  They will bump into objects in the environment, but still not recognize that they cannot see.  This is attributed to the Hetero-Modal cortex (also called the association cortex), two areas in the frontal cortex and posteriorly in the confluence of the temporal, occipital, and parietal lobes.  These areas receive input from multiple unimodal sensory and motor areas and create an integrated and coherent model of the environment.  In Anton’s syndrome, the hetero-modal cortex maintains this integrated model even though there is no visual input. 

We ended our discussion here.

Here are the two Chinese pictograms described above:

看 = look The symbol for hand over the symbol for eye.
Unknown copy.png

 

Screenshot 2017-11-15 16.05.14.png

見       In its unsimplified form the upper part is a symbol of eye, while the lower part symbolises a man, thus forming the meaning "to see"

Respectfully,
Michael J. Solomon, MD 

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[#17]  First Mist in the Universe

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[#17] First Mist in the Universe

When the Universe was ten microseconds old, mist started to form in the Universe.  By the time the Universe reached the age of a hundred microseconds, the mist was complete: the Universe was drenched in tiny quark-gluon droplets that would become the protons and neutrons in the nuclei of the atoms that our bodies are built out of.

By Piet Hut

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Synopsis of Michael Solomon’s YHouse Lunch talk 10/26/17 Cancer As A Metabolic Disease

TITLE:  Is cancer a metabolic disease caused by mitochondrial dysfunction?

ABSTRACT:  For the past 40 years we have thought of cancer as the result of somatic mutations in nuclear DNA that either block tumor suppressor genes or unblock oncogenes resulting in malignant transformation.  But our success in understanding or in treating cancer has been sadly limited. Thomas Seyfried and others have made a strong case that, in fact, cancer results from the loss of the cell’s ability to obtain energy (ATP) via oxidative phosphorylation, resulting in the cancer cell’s reverting to more primitive metabolic pathways and fermenting glucose (and the amino acid glutamine) even in the presence of adequate oxygen (aerobic glycolysis).  This theory was originally suggested by Otto Warburg in the 1940’s, the so-called Warburg effect.  I will offer evidence supporting the possibility that malignant transformation in all cancer is a metabolic disease resulting from mitochondrial dysfunction and is not a genetic disease caused by nuclear DNA changes which occur secondarily.  This leads to alternative management strategies for cancer without toxic radiation or chemotherapy.....

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Synopsis of Olaf Witkowski’s Consciousness Club Talk 10/25/2017

Abstract:  Information is found all across the domain of physics, seemingly retaining all its properties regardless of the media in which it is instantiated. Substrate-independence and interoperability made possible symbolic representations such as the genetic code, allowing for life to develop upon it. The next transition closed the loop by producing organisms increasingly aware of their environment. This eventually led to human life, capable of learning the underlying principles that created it, with the invention of language and science.
      I focus my research on collective cognition, which one can see as the informational software to life's physical hardware......

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[#16]  Evolution of Parts and Wholes in Life-Like Entities

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[#16] Evolution of Parts and Wholes in Life-Like Entities

In nature, culture, and technology, surprising novelty has appeared as products of ongoing evolution.  Many new forms  of organization are themselves remarkably life-like.  A key aspect is that their building blocks evolve together with  their structures and processes -- and so do we, as building blocks of many overlapping societal systems.

By Piet Hut

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Synopsis of 9/30/17 YHouse Lunch talk by Ohad Nachtomy

Title: The Psycho-Physical Lab

Ohad is working on a book with this title about the Mind/Body problem in philosophy and links to the practice of Yoga.  This book is not intended as an academic contribution to research but for a broader audience.  His coauthor, Eyal  Shifroni, Has been a yoga teacher for years.  He argues that reflective yoga practice goes beyond health, but offers a way to engage body and mind to train each other.  We use our physical abilities and limitations to train our mental capacities, and vice versa, to improve each.  Reflective practice is essential to development.  He emphasizes practice with less effort and more attention.  This does involve posture and breathing exercises, but to what purpose?  We cannot make sense of mental states without referring to our physical bodies.  Body and Mind are interconnected.  We train the body through reflective processes and improve the whole being......

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SYNOPSIS OF LIAT LAVI'S IAS LUNCHEON TALK ON SEPT. 28, 2017

In my talk I will present the account of understanding I am developing under the title of 'expectationalism'. The account draws heavily on Jamesian Pragmatism and the thought of Heidegger and Merleau-Ponty. Its central premises are: 1. That the meaning of something is its consequences, and to understand something is to grasp its consequences. and 2. That expectations are not some internal content, but are rather actualized by our bodies. I will link this account with contemporary approaches in cognitive science and philosophy of mind, and suggest that if the account is correct this implies that strong AI is possible and that limited instances of it already exist......

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[#15]  Computer Simulations as Dynamical Metaphors

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[#15] Computer Simulations as Dynamical Metaphors

To point out something really new, we can use a quick metaphor or we can take our time to tell a story that is richer in details.  A computer simulation can do both: pointing out a few salient characteristics of a situation as a kind of metaphor, and then letting it run to dynamically produce its own narrative.

By Piet Hut

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Synopsis of Randall Beer’s YHouse Luncheon talk 10/19/17

Abstract: "I will briefly describe two intertwined research programs. The first concerns issues of embodiment, situatedness and dynamics in understanding how an animal's behavior arises from the interaction between its nervous system, its body and its environment. Specifically, we use genetic algorithms to evolve model brain-body-environment systems and then analyze their operation using the tools of dynamical systems theory and information theory. This approach has been applied to a wide variety of behaviors, including locomotion, action-switching, learning, categorization, selective attention, and referential communication. The second concerns the organization of minimal living systems and its consequences. Specifically, we analyze  persistent spatiotemporal entities in cellular automata models from the perspective of autopoiesis and enaction. We identify the local processes that underlie

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Synopsis of Consciousness Club talk Oct. 11, 2017 by Yuko Ishihara

Speaker:  Yuko Ishihara
Title:  Consciousness: not a “thing” but a “place”.
We Work, 110 E 28th Street NYC, NY.

Abstract:  Modern western thought has given consciousness a special place in the understanding of human beings. According to Descartes, it is the fact that we are "thinking things" that sets us apart from unconscious things like a desk or a pen. While scientists and philosophers today disagree with Descartes on what constitutes the nature of the thinking thing, most people agree on the basic Cartesian assumption: that consciousness is a kind of "thing."
But can we not question this assumption? Putting aside all theories, our direct experience teaches us that consciousness does not primarily appear as a thing. Rather, it appears more as a ground or "place" wherein our experience occurs. Drawing on insights from twentieth-century philosophers like Martin Heidegger and Nishida Kitaro who developed a philosophy of place, let us think together about what it really means to understand consciousness not as a "thing" but as a "place." Perhaps such ideas can open doors towards a better understanding on the nature of consciousness.
    

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[#14]  Kindred Spirits: Meeting Carl Pabo

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[#14] Kindred Spirits: Meeting Carl Pabo

This weekend I flew out to San Francisco, to meet Carl Pabo.  We have only met a few times since we first met 12 years ago, but we are clearly kindred spirits.  We both want to radically change the way our society deals with knowledge, and after a few decades of exploration, we each are in the process of building up an organization that aims at doing just that.  The difference is . . . 

By Piet Hut

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[#13]  Experiencing Theory: The Gate To Understanding

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[#13] Experiencing Theory: The Gate To Understanding

Science is based on theory and experiment.  But to understand theory, we need to experience theory.  Unless we fall into an experience of mathematics, we cannot know what theory means, and we cannot compare theory and experiment.  In experiencing theory, I have encountered three very different levels of insight.

By Piet Hut

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Synopsis of YHOUSE CONSCIOUSNESS CLUB TALK by PIET HUT SEPTEMBER 13, 2017

Synopsis of YHouse Consciousness Club Talk September 13, 2017
Speaker:  Piet Hut
Location:  WeWork 110 E. 28th St. NYC
Title:  The Nature Of Reality

Following introductions of YHouse by Sean Sakamoto and of Piet by Ed Turner, 
      Piet began noting that his topic included everything in the Universe, but he would focus on the Nature of Consciousness and Cognition.  Although he is a scientist he would be influenced by his reading of both Western and Eastern Philosophy, areas he has been deeply involved in for decades.
     Forty or fifty years from now.....

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[#11]  Pioneering Years in AI in Astrophysics

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[#11] Pioneering Years in AI in Astrophysics

This week, exactly thirty years ago, Scientific American published a special issue on advanced computing.  My computer scientist friend, Gerald Sussman, and I received the honor of being asked to write the article on Advanced Computing for Science.  All of science!  That was a daunting task.
By Piet Hut

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[#10]  The Nature of Reality: Matter, Experience, Appearance, Presence

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[#10] The Nature of Reality: Matter, Experience, Appearance, Presence

A few days ago I gave a short talk, followed by a much longer discussion, in the Consciousness Club series at YHouse.  The topic was the nature of reality, with the full title "Matter, Experience, and Reality".  Actually, I wound up talking about two more aspects of reality that we consciously partake in: what I like to call appearance and presence.
By Piet Hut

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[#9]  Mind and Magnetic Monopoles: Matter, Mind and Magic

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[#9] Mind and Magnetic Monopoles: Matter, Mind and Magic

Breakthroughs in science are often triggered by a realization that one or more of our assumptions were wrong.  In the rapid growth of experimental and theoretical insights in neuroscience, which of the underlying assumptions could be candidates for revision, potentially inducing a big shift in understanding?
By Piet Hut

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