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Salam to Young

Salam
Abdus Salam


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'D' wing of R&D





brain activity



All chemical binding is electromagnetic in origin,
and so are all phenomena of nerve impulses. ~Salam


 

  

schrodinger
Erwin Schrödinger


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If you ask a physicist what is his idea of yellow light, he will tell you that it is transversal electromagnetic waves of wavelength in the neighborhood of 590 millimicrons. If you ask him: But where does yellow come in? he will say: In my picture not at all, but these kinds of vibrations, when they hit the retina of a healthy eye, give the person whose eye it is the sensation of yellow.


Schrödinger

laser


What this something is cannot be said; by calling it matter or field or whatnot, we just give it a name. The relevant point is that it is not supposed to have any other properties but geometrical configuration, changing in time according to certain "laws of nature." It is not in itself yellow or green, sweet or cold. If parts of it appear to us so, there is no hard, indubitable fact to make this judgment true or false.

This view is strongly supported by our analysis of actual experimental procedure, and it is attractively simple. It carries us comfortably a long way, indeed so long, that we may have forgotten its artificiality, when we meet the obstacles that it renders unsurmountable. So it is better to ask the naive but very pertinent question right away: how do red and yellow, sweet and hot come in at all? Once we have removed them from our "objective reality," we are at a desperate loss to restore them. We cannot remove them entirely, because they are there, we cannot argue them away. So we have to give them a living space, and we invent a new realm for them, the mind, saying that this is where they are, and forgetting the earlier part of the storyall that we have been talking about till nowis also in the mind and nowhere else. But deeming it to be something elseobjective realitywe run against the unanswerable question: how does matter act on mind, to produce in it the sensory qualitiesand also how does mind act on matter, to move it at will? These questions cannot, so I believe, be answered in this form, and they owe their embarrassing form precisely to our having posited an objective reality which is a pure geometrical scheme of thought and deprived of everything real given by experience.

Schrödinger


John Searle
John Searle




The question we wanted to ask is this: 'Can a digital computer, as defined, think?' That is to say, 'Is instantiating or implementing the right computer program with the right inputs and outputs, sufficient for, or constitutive of, thinking?' And to this question, unlike its predecessors, the answer is clearly 'no.' And it is 'no' for the reason that we have spelled out, namely, the computer is defined purely syntactically. But thinking is more than just a matter of manipulating meaningless symbols, it involves meaningful semantic contents. These semantic contents are just what we mean by 'meaning.'

Searle

Henry Stapp
Henry Stapp


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All of these materialistic-type theories are now known to be false: they provide no adequate basis for understanding the structure of our experience.

Quantum theory is the newest contender. It accomodates all of the empirical evidence accepted by the scientific community.

It differs from the materialistic theories in three essential respects.

First, it is not designed to be a description of a reality that exists independently of human observers. Rather it is designed to be a computational procedure that allows us to form expectations about our future experiences — as we describe them to ourselves and to our colleagues in a suitable language — on the on the basis of knowledge gleaned from previous similarly described experiences.

Second, it is an incomplete description, in the sense that there is a random element whose origin and mode of acting is not specified.

Third, the ontological character of the "object" described by the theory is, on the basis of how it behaves, more like "knowledge" than like the matter of the materialistic theories: it makes sudden "jumps"that extend over all of space when an increment in knowledge occurs. Thus the theory is not about matter, as matter was conceived of in, say, the classical physical theory stemming from the works of Newton and Maxwell.


§

The fundamental logical structure of quantum theory expresses the information that describes the actual state of any system S large or small, in terms of the plus one or zero eigenvalues of a set of projection operators in the Hilbert Space associated with that system S! These projection operators must be orthogonal (Pi Pj = Pi   δij) and sum to unity: (i.e., be a decomposition of unity.) For any such set there is basis in the Hilbert space such that each of the projectors in this set is represented by a matrix that is filled with zeros and ones, with all the ones located only on the diagonal. Different choices of basis allow different “mutually consistent” sets of P’s to be defined. But the key point is that only sets of P’s that are all mutually orthogonal give allowed “mutually consistent” sets of Yes/No bits of information. Two projection operators that cannot be expressed in terms of a set of ones lying on the diagonal in some one common basis are not mutually compatible: no actual state can be specified by giving, simultaneously, their eigenvalues.

projection

Projection

Gerard 't Hooft

Gerard 't Hooft

'D' wing of R&D




A theory that yields "maybe" as an answer should be recognized as an inaccurate theory.

§

A field is simply a quantity defined at every point throughout some region of space and time.

color sphere

It is easy to imagine a global color symmetry. The quark colors, like the isotopic- spin states of hadrons, might be indicated by the orientation of an arrow in some imaginary internal space.
't Hooft




Turing
Alan Turing



 
I


I propose to consider the question, 'Can machines think?' This should begin with definitions of the meaning of the terms 'machine' and 'think.'


Turing machine


I do not wish to give the impression that I think there is no mystery about consciousness. There is, for instance, something of a paradox connected with any attempt to localise it.

Turing





John von Neumann
John von Neumann


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First, it is inherently entirely correct that the measurement  or the related process of the subjective perception is a new entity relative to the physical environment and is not reducible to the latter. Indeed, subjective perception leads us into the intellectual inner life of the individual, which is extra-observational by its very nature (since it is taken for granted by any conceivable observation or experiment). Nevertheless, it is a fundamental requirement of the scientific viewpointthe so-called principle of the psycho-physical parallelismthat it must be possible to describe the extra-physical process of the subjective perception as if it were in reality in the physical worldi.e., to assign to the parts equivalent physical processes in the objective environment, in ordinary space.

§

A new, essentially logical, theory is called for in order to understand high-complication automata and, in particular, the central nervous system. It may be, however, that in this process logic will have to undergo a pseudo- morphosis to neurology to a much greater extent than the reverse.


Von Neumann

Herman Weyl
Hermann Weyl


'D' wing of R&D

The processes on the retina produce excitations which are conducted to the brain in the optic nerves, maybe in the form of electric currents. Even here we are still in the real sphere. But between the physical processes which are released in the terminal organ of the nervous conductors in the central brain and the image which thereupon appears to the perceiving subject, there gapes a hiatus, an abyss which no realistic conception of the world can span. It is the transition from the world of being to the world of appearing image or of consciousness.






Epistemologically it is not without interest that in addition to ordinary space there exists quite another domain of intuitively given entities, namely the colors, which forms a continuum capable of geometric treatment.

§

The characteristic of an n-dimensional manifold is that each of the elements composing it (in our examples, single points, conditions of a gas, colors, tones) may be specified by the giving of n quantities, the "co-ordinates," which are continuous functions within the manifold.

wave superposition


Thus the colors with their various qualities and intensities fulfill the axioms of vector geometry if addition is interpreted as mixing; consequently, projective geometry applies to the color qualities.

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color superposition


Weyl

Whitehead
Alfred North Whitehead



The sense-object is the simplest permanence which we trace as self-identical in external events. It is some definite sense-datum, such as the color red of a definite shade. We see redness here and the same redness there, redness then and the same redness now. In other words, we perceive redness in the same relation to various definite events, and it is the same redness which we perceive. Tastes, colors, sounds, and every variety of sensation are objects of this sort.

Whitehead

Thus "this is red," "this is earlier than that," are atomic propositions.

Russell & Whitehead

redness of red redness of red redness of red

A = B & B = C > A = C

  

Wigner
Eugene Wigner


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Since matter clearly influences the content of our consciousness, it is natural to assume that the opposite influence also exists, thus demanding the modification of the presently accepted laws of nature which disregard this influence.

Wigner 

Hidden symmetry

R L Ingraham summarised some of the many contributions made by Wigner. These include his:... epoch-making work on how symmetry is implemented in quantum mechanics, the determination of all the irreducible unitary representations of the Poincaré group, and his work with Bargmann on realizing those irreducible unitary representations as the Hilbert spaces of solutions of relativistic wave equations, ... discrete symmetries and superselection rules in quantum mechanics, symmetry implications for atomic and molecular spectra, natural line-width theory, contrast of microscopic and macroscopic physics and of general relativity and quantum mechanics, explanation of why symmetry yields more information for quantum than for classical mechanics, philosophical questions such as what nature laws should be, limits on causality, and whether quantum mechanics could in principle explain life.



Ludwig Wittgenstein
Ludwig Wittgenstein


'D' wing of R&D

The feeling of an unbridgeable gulf between consciousness and brain-process:wordassociation how does it come about that this does not come into the considerations of our ordinary life? This idea of a difference in kind is accompanied by slight giddiness — which occurs when we are performing a piece of logical sleight-of-hand. (The same giddiness attacks us when we think of certain theorems in set theory.) When does this feeling occur in the present case? It is when I, for example, turn my attention in a particular way on to my own consciousness, and, astonished, say to myself: THIS is supposed to be produced by a process in the brain!

§

The aspects of things that are most important for us are hidden because of their simplicity and familiarity.

§

Is there such a thing as a 'natural history of colors' and to what extent is it analogous to a natural history of plants? Isn't the latter temporal, the former non-temporal?

§

A speck in the visual field, though it need not be red must have some color; it is, so to speak, surrounded by color-space. Notes must have some pitch, objects of the sense of touch some degree of hardness, and so on.

§

When we're asked "What do 'red', 'blue', 'black', 'white' mean?" we can, of course, immediately point to things which have these colors — but that's all we can do: our ability to explain their meaning goes no further.

Wittgenstein

Yau
Shing Tung Yau


projective geometry


String theory has provided a very rich background to study geometry of Ricci flat metrics. Duality concepts have provided very powerful tools. The construction of SYZ needs to be explored much further, both in terms of construction of special Lagrangian cycles and the perturbation of semi-flat Ricci flat metrics to Ricci flat metrics in terms of holomorphic disks. The fundamental questions in complex geometry are

(1) To find a topological condition so that an almost complex manifold admits an integrable complex structure.

(2) To find a way to determine which integrable complex structure admits Kahler metrics, or weaker form of Kahler metrics, e.g., balanced metrics. There are Hermitian metrics omega Hermitian metric

(3) To find a way to deform a Kahler manifold to a projective manifold.

(4) To characterize those projective manifolds in terms of algebraic geometric data that can be defined over Q

(5) Study algebraic cycles and algebraic vector bundles (or more generally, derived

(6) To understand moduli space of algebraic structures and the above algebraic objects.
so that category of algebraic manifolds).

Yau




Thomas Young
Thomas Young

Polymaths have always posed a problem in academia. How do they relate to specialization and interdisciplinarity, genius and dilettantism, inspiration and perspiration? Robert Hooke, Benjamin Franklin and Alexander von Humboldt were among those who were too academically wide-ranging for posterity to cope with, and their scientific reputations suffered as a consequence. Individual curiosity is the driving force of science, but when insatiable, can it hamper the intellectual? The life and work of the polymath Thomas Young (1773-1829) illuminates the issue perhaps more acutely than that of any other scientist. Today, views of Young span the spectrum from near-universal genius to dabbling dilettante.

ScienceWeek  


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RGB superposition

Color and Stereoscopic Vision

Color vision is based on the ability to discriminate between the various wavelengths that constitute the spectrum. The Young-Helmholtz theory, developed in 1802 by Thomas Young and H. L. F. Helmholtz, is based on the assumption that there are three fundamental color sensations—red, green, and blue—and that there are three different groups of cones in the retina, each group particularly sensitive to one of these three colors. Light from a red object, for example, stimulates the cones that are more sensitive to red than the other cones. Other colors (besides red, green, and blue) are seen when the cone cells are stimulated in different combinations. Only in recent years has conclusive evidence shown that the Young-Helmholtz theory is, indeed, accurate. The sensation of white is produced by the combination of the three primary colors, and black results from the absence of stimulation.


RGB sensitivities


field fx