1. Albert Einstein & the Question of Reality
600
million
mph
Dennis Blejer
October 21, 2006

2. Tagore on Einstein Einstein is an excellent interrogator.”
“His is what might be called transcendental materialism,
which reaches the frontiers of metaphysics, where there can be
utter detachment from the entangling world of self.
To me both science and art are expressions of our spiritual nature, above our biological necessities and possessed of an ultimate value.
Einstein is an excellent interrogator.”

3. “Everything should be made as simple as possible,
but not simpler."
E=mc 2

4. Motivation
Is the universe real? What is the nature of physical reality? Read from: A. Einstein, Philosopher-Scientist, p 248 & p 5.
“Any one who looks at the creation and wants to know about it finds diverse manifestations. So he wants to know what force is working behind it, who has made it possible, or what is that force which has brought about such a gigantic creation in existence and keeps it going?” - Shantananda Saraswati, 1965
Physical science also asks “what are the basic elements of the universe and how do they interact?” (Matter, energy, space, time, force)
Albert Einstein figures prominently in the scientific discussion on what is reality?

5. Let me tell you what I am going to tell you
Outline
Let me tell you what I am going to tell you
Motivation
Locality, determinism, realism, and instrumentalism
Physics circa 1900
Einstein’s contributions to physical theory
Quantum physics and the Copenhagen Interpretation
EPR, Bell’s Theorem, Schrödinger's Cat, and Wigner’s Friend
What is the world? (A. Watts, Shantananda (1965), Shankara (Brihad.), and Plato’s allegory of the cave)
Discussion

6. Locality, Determinism, Realism, and Instrumentalism
Locality: The notion that two systems that are distant from one another cannot interact instantaneously. A finite amount of time is required for one system to influence the other. Locality is related to causality (A. Einstein)
Determinism: The evolution of a system in space and time is causally determined and can be predicted from scientific laws that are expressed mathematically (A. Einstein)
Realism: The notion that scientific investigation and the resulting theories are dealing with things that actually exist, e.g., the atom (read from Popper, p. 2.) (A. Einstein)
Instrumentalism: The notion that scientific theories are not statements about “reality”, but are only useful for predicting the results of experiments (“There is no quantum world, only an abstract quantum description”, N. Bohr)

7. Physics Circa 1900 Newtonian Mechanics
Motion of material objects with or without forces that take place in a universe characterized by absolute space and time
Conceptually simple (not mathematically!)
Applicable to celestial mechanics (astronomy), motion of solids, liquids, gases (rigid body mechanics, elasticity theory, fluid mechanics) and, thermodynamics (heat and kinetic theory)
Non-local, deterministic, and realistic (?)
Electromagnetism (unified theory of electric and magnetic forces)
Motion of light and non-ionizing radiation
Field theory (dynamic and not conceptually simple)
Explained light as an electromagnetic wave (Maxwell)
Optics as a limiting case
Predicts radio waves and is the basis for much modern technology
Local, deterministic, realistic (???)

8. The Major Problems in Physics (that Influenced Einstein)
Poincaré, 1902, La Science et l’Hypothèse
UV light ejects electrons from the surface of a metal
Zigzag motion of pollen particles suspended in a liquid
No ether drift (constancy of the velocity of light)
Lord Kelvin
The failure of the Rayleigh-Jeans law to predict the distribution of radiant energy in a black body
Ernst Mach, 1893, The Science of Mechanics
Critic of Newtonian Mechanics
No absolute space and time
Ice skater and the stars
Atomic Hypothesis
Not completely accepted at the time

9. Blackbody Intensity as a Function of Frequency
The problem that started the quantum revolution
Energy is quantized

10. Einstein
Einstein accepts Planck’s notion that energy is quantized to explain the photoelectric effect
He accepts that the speed of light is constant, independent of the motion of the source or receiver
He accepts the atomic hypothesis to explain Brownian motion

11. Einstein’s Contributions in 1905 His miracle year
In 1905 Einstein is an unknown physicist working in a Swiss patent office – at the age of 26 he publishes 5 papers, 3 of which are seminal papers
On a Heuristic Point of View about the Creation and Conversion of Light (Photoelectric Effect, Nobel Prize, 1921).
“There is a profound formal difference between the theoretical ideas which physicists have formed concerning gases and other ponderable bodies and Maxwell’s theory of electromagnetic processes in so-called empty space.”
A New Determination of Molecular Dimensions (doctoral thesis)
On the Movement of Small Particles Suspended in Stationary Liquids Required by the Molecular-Kinetic Theory of Heat (Brownian Motion)
On the Electrodynamics of Moving Bodies (Special Relativity)
“It is known that Maxwell’s electrodynamics as usually understood at the present time when applied to moving bodies, leads to asymmetries which do not appear to be inherent in the phenomena.”
Does the Inertia of a Body Depend on Its Energy Content? (E=mc2)
Read from ‘Einstein 1905’

12. Einstein’s Contributions - Post 1905
The Foundation of the General Theory of Relativity – – New theory of gravity that is local
The Quantum Theory of Radiation – 1917
Derives the Planck black body radiation formula from more fundamental considerations
Quantum Theory of Single Atom Ideal Gases – 1924
Bose-Einstein statistics
Can Quantum-Mechanical Description of Physical Reality be Considered Complete? – 1935
EPR paper
Unified Field Theory and Cosmology

13. ‘The Foundations of the General Theory of Relativity’,
General Relativity
“In classical mechanics, and no less in the special theory of relativity, there is an inherent epistemological defect which was, perhaps for the first time, clearly pointed out by Ernst Mach.”
“We shall soon see that the general theory of relativity cannot adhere to this simple physical interpretation of space and time.”
From
‘The Foundations of the General Theory of Relativity’,
A. Einstein, 1916

14. The Essence of General Relativity
Einstein discovered in his General Theory of Relativity that gravity and acceleration are the same phenomenon
Read from ‘Principle of Relativity’ p 100, ‘But we arrive…’ g
Ball on left falls due to gravity
Ball on right appears to fall due to acceleration of elevator upward
(no gravity)
Bending of light in a gravitational field

15. Implications of the General Theory
Light bends in a gravitational field
Clocks measure time at different rates in a gravitational field
Black Holes
Requires the synthesis of general relativity and quantum mechanics
Multiple universes
Is the universe expanding?

16. General Covariance General covariance Wikipedia, the Free Encyclopedia
In theoretical physics… a physical law expressed in a
generally covariant fashion takes the same mathematical
form in all coordinate systems… The general principle of
relativity, as used in GR, is that the laws of physics must
make the same predictions in all reference frames.

17. Albert Einstein Quotes
"I want to know God's thoughts; the rest are details."
"Reality is merely an illusion, albeit a very persistent one."
"The only real valuable thing is intuition.“
“Physics is an attempt to grasp reality as it is thought independently of it being observed.”
"I am convinced that He (God) does not play dice."
"The eternal mystery of the world is its comprehensibility."
"Science without religion is lame. Religion without science is blind."
"The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead: his eyes are closed."

18. Quantum
Mechanics

19. Instability According to Classical Theory
Rutherford’s Atomic Model (1911)

20. Quantum Contributors Schrödinger Pauli Heisenberg Kramers Dirac
Compton
De Broglie
Born
Bohr
Planck
Curie
Lorentz
Einstein 1 2 3 9 4 7 5 6 8 10 11 12 13
From: Einstein vs. Bohr

21. Quantum Mechanics in a Nutshell
Quantization of energy
Wave-particle duality
Diffraction

22. Diffraction from a Dielectric Cylinder
Wave behavior of light (electromagnetic radiation) was well established

23. Double Slit Diffraction
No interference
interference
interference

24. Wave-Particle Diffraction Electrons behave as waves!
From: ‘The Story Book of Quantum Mechanics’

25. Electron Diffraction – One at a Time!

26. How to detect an electron (Uncertainty Principle) How to measure position and velocity

27. Quantum Mechanics Schrödinger's Equation
What does the wave function solution mean?
First time in physics that founder’s explanation was not accepted
Probabilistic interpretation
Collapse of wave function upon measurement (flipping a coin)

28. Copper-Oxygen Bond in Cuprite The shape of the five 3d orbitals
Electron Orbitals
Copper-Oxygen Bond in Cuprite
(Cu2O)
The shape of the five 3d orbitals
Nature, September 1999
Zuo, Kim, O’Keeffe and Spence
Arizona State University/NSF

29. Copenhagen Interpretation
Born’s probabilistic interpretation - Physics and Philosophy, p. 46.
Bohr’s Complementarity Principle - Physics and Philosophy, p. 49.
Heisenberg’s Uncertainty Principle - Physics and Philosophy, p. 42.
Conclusions - Physics and Philosophy, p. 55.
QM is non-local, non-deterministic, and non-realistic - Einstein could not accept this interpretation!

30. Heisenberg Quotes on QM
All of my meager efforts go toward killing off and suitably replacing the concept of the orbital path which one cannot observe.
Heisenberg, letter to Pauli, 1925
The present paper seeks to establish a basis for theoretical QM founded exclusively upon relationships between quantities which in principle are observable.
Heisenberg, 1st paper on QM
The more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa.
Heisenberg., Paper of 1925
Can nature possibly be as absurd as it seemed to us in these atomic experiments?
Physics and Philosophy
We regard quantum mechanics as a complete theory for which the fundamental physical and mathematical hypotheses are no longer susceptible of modification. (!!!)
Heisenberg and Born, 1927

31. Nobody Understands Quantum Mechanics
Those who are not shocked when they first come across quantum theory cannot possibly have understood it.
I… do not know what quantum mechanics is. I think we are dealing with some mathematical methods which are adequate for description of our experiment. Using a rigorous wave theory we are claiming something which the theory cannot possibly give. We are away from the state where we could hope of describing things on classical theories…
– Neils Bohr
I can safely say that nobody understands quantum mechanics. ...
Do not keep saying to yourself, if you can possibly avoid it, 'But how can it be like that?' because you will get 'down the drain', into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that.
– Richard Feynman

32. Einstein Quotes on QM
The theory yields a lot, but it hardly brings us any closer to the secret of the Old One. In any case I am convinced that He does not throw dice.
Einstein to Born, 1926
Like the moon has a definite position whether or not we look at the moon, the same must also hold for the atomic objects, as there is no sharp distinction possible between these and macroscopic objects. Observation cannot create an element of reality like a position, there must be something contained in the complete description of physical reality which corresponds to the possibility of observing a position, already before the observation has been actually made.
The laws of nature imply complete causality (radioactivity)
The Heisenberg-Bohr tranquillizing philosophy – or religion? – is so delicately contrived that, for the time being, it provides a gentle pillow for the true believer from which he cannot very easily be aroused. So let him lie there.

33. Einstein-Bohr Debates
A series of discussions, debates, and arguments, both formal and informal, took place between Albert Einstein and Niels Bohr in the post-Copenhagen Interpretation era on the nature of physical reality and whether QM is a complete theory - Read from “Discussions with Einstein”, Niels Bohr, p. 1.

34. EPR Paper
Can Quantum-Mechanical Description of Physical Reality be Considered Complete?
A. Einstein, B. Podolsky and N. Rosen, Physical Review, May 15, 1935
Read first page of paper
“The EPR experiment was formulated on the basis that either an independent reality did not exist or quantum mechanics was an incomplete theory.
Being a realist, Einstein firmly believed the latter.
The thought experiment addressed the problem of whether a particle could have both a definite momentum and a definite position. E, P, and R, devised a scheme in which it appeared that both these quantities could in principle at least, be measured to any desired degree of accuracy – so contradicting the uncertainty principle.
Two particles, A and B, interact and then separate until they are quite far apart. It is possible to measure the momentum of particle A directly, and perform a calculation to determine the momentum of particle B. While it is not possible to know the position of particle A, because of the measurement performed on it, it is possible to determine the position of particle B directly. Consequently, the momentum and position of particle B can be determined, thereby, circumventing Heisenberg and demonstrating the incompleteness of quantum mechanics.”
- From: Quantum Reality, Manjit Kumar

35. Bohr’s Response to EPR and Bell’s Theorem
Can Quantum-Mechanical Description of Physical Reality be Considered Complete?
N. Bohr, Physical Review, October 15, 1935
Read first page
Read “From Einstein’s Theorem to Bell’s Theorem: A History of Quantum Non-Locality”, Section (Bohr’s Reply)
Bell’s Theorem states that a violation of Bell’s Inequality is equivalent to a refutation of EPR
- From: The Copenhagen Interpretation of QM, Ben Best
“In the early 1980s, a version of the EPR experiment was performed in the laboratory.
For the present, the experiments appear to come down in favor of the Copenhagen interpretation and against Einstein’s realism. But, accepting that the results of these experiments favour the Copenhagen position involves rejecting one of three premises on which Einstein based his position. These were that: inductive logic is valid; objective reality exists; it is impossible to travel faster than light. …
The most popular interpretation of the experimental results is that while objective reality exists independent of observation, the speed of light can be exceeded.
But difficulties then arise for the theory of relativity, since it is fundamental to this theory that nothing can travel faster than light.”
- From: Quantum Reality, Manjit Kumar

36. Schrödinger's Cat Is the cat both dead and alive?
From: Einstein versus Bohr, Mendel Sachs

37. Wigner’s Friend From Wikipedia, the free encyclopedia
Wigner's friend is a thought experiment proposed by the physicist Eugene Wigner; it is an extension of The Schrodinger’s Cat experiment designed as a point of departure for discussing the mind-body problem as viewed by the Copenhagen Interpretation of quantum mechanics. In the Copenhagen Interpretation, the collapse of the wavefunction is said to take place when a quantum system is measured. Essentially, the Wigner's friend experiment asks the question: at what stage does a "measurement" take place? It posits a friend of Wigner who performs the Schrodinger’s experiment while Wigner is out of the room. Only when Wigner comes into the room does he himself know the result of the experiment: until this point, was the state of the system a superposition of "dead cat/sad friend" and "alive cat/happy friend," or was it determined at some previous point? Wigner designed the experiment to highlight how he believed consciousness is necessary to the quantum mechanical measurement process. The idea has become known as the consciousness causes collapse interpretation, or less flatteringly, the spiritual interpretation.

38. Quotes from Bell and Gell-Mann
Well it does not really explain things; in fact the founding fathers of quantum mechanics rather prided themselves on giving up the idea of explanation. They were very proud that they dealt only with phenomena: they refused to look behind the phenomena regarding that as the price one had to pay for coming to terms with nature.
– Bell
Bohr and Heisenberg brainwashed a whole generation of physicists into thinking that the job was done 60 years ago’.
- Gell-Mann

39. What is a Thing? It’s a noun.
As reported by Alan Watts
Everything exists in name and shape only.
Brahman is real, the world is an illusion, the individual and the Absolute are not different.
Shankara

40. Shankara
“Therefore the whole universe consisting of a series of meditations and rites, means and ends, actions and results – although, being held together by a stream of work and impressions of innumerable beings in combination, it is transient, impure, flimsy, resembling a flowing river or a burning lamp, flimsy like a banana stalk, and comparable to foam, illusion, a mirage, a dream, and so on – appears, nevertheless to those who have identified themselves with it to be undecaying, eternal and full of substance.”
- Shankara, commentary on the Brihadaranyaka Upanishad, I.v.2

41. Shantananda Saraswati
“Take up anything and look into it seriously and you will find that essentially it is nothing but a manifestation of the same consciousness, bliss and truth. Although in the physical manifestation, color, form, tree, juice, skin, etc. are all related to mango, yet essentially it is that formless consciousness, a concept of that real knowledge which is Sachidananda.”
- Shantananda Saraswati, Conversations with Mr. L. MacLaren, 1965.

42. Plato’s Republic, Book VII
This entire allegory, I said, you may now append, dear Glaucon, to the previous argument; the prison-house is the world of sight, the light of the fire is the sun, and you will not misapprehend me if you interpret the journey upwards to be the ascent of the soul into the intellectual world according to my poor belief, which, at your desire, I have expressed whether rightly or wrongly God knows.
But, whether true or false, my opinion is that in the world of knowledge the idea of good appears last of all, and is seen only with an effort; and, when seen, is also inferred to be the universal author of all things beautiful and right, parent of light and of the lord of light in this visible world, and the immediate source of reason and truth in the intellectual; and that this is the power upon which he who would act rationally, either in public or private life must have his eye fixed.

43. Backup Slides

44. “Everything should be made as simple as possible,
but not simpler."

45. The Essence of General Relativity
Einstein discovered in his General Theory of Relativity that gravity and acceleration are the same phenomenon
Read from ‘Principle of Relativity’ p 100, ‘But we arrive…’
Ball in box on left falls due to gravity
Ball in elevator on right appears to fall due to acceleration of elevator upward (no gravity)
Bending of light in a gravitational field g

46. Cell Phone System Diagram Texas Instruments

47. “On the Electrodynamics of Moving Bodies”
Observations of a Moving Compass by a Stationary Observer and One Moving with a Compass
Both observers see the compass point towards the electrically charged sphere
The two observers have different explanations for what is happening
- One claims a magnetic interaction, the other, an electric interaction
Moving observer e─
Stationary observer
Read introduction to
“On the Electrodynamics of Moving Bodies”

48. “Everything should be made as simple as possible,
General Relativity
“Everything should be made as simple as possible,
but not simpler.”
- Albert Einstein -
Einstein's Field Equation (EFE) is usually written in the form:
Rμν is the Ricci curvature tensor
R is the Ricci scalar (the tensor contraction of the Ricci tensor)
gμν is a (symmetric 4 x 4) metric tensor
Λ is the Cosmological constant
π is pi = , the ratio between a circle's circumference and diameter
G is the Gravitational constant
c is the speed of light in free space
Tμν is the energy-momentum stress tensor of matter
Where
The EFE equation is a tensor equation relating a set of symmetric 4x4 tensors. It is written here in terms of components. Each tensor has 10 independent components. Given the freedom of choice of the four space-time coordinates, the independent equations reduce to 6 in number.
The EFE is understood to be an equation for the metric tensor gμν (given a specified distribution of matter and energy in the form of a stress-energy tensor).
E=mc 2
DESPITE THE SIMPLE APPEARANCE OF THE EQUATION IT IS, IN FACT, QUITE COMPLICATED.
This is because both the Ricci tensor and Ricci scalar depend on the metric in a complicated nonlinear manner.

49. Einstein – Brief Sketch By Leiwen Wu
1879: Einstein born Ulm, Germany.
: Michelson and Morley began a series of puzzling experiments which made the Newtonian Universe impossible.
1900: Max Planck shocked the physics community with the concept of quantization
1905: The miracle year in physics: Einstein published papers on Brownian motion as well as the seminal papers on his theory of relativity. He developed the Special Theory of Relativity in which he described how space and time are relative or related to each other.
1915: Einstein extended his discussion of relativity to include gravity and thereby explained the problem of Mercury. He developed the general theory of relativity which dealt with gravity and acceleration and a 4 dimensional space in which everything is related to each other.
1919: Eddington confirms Einstein's prediction concerning deflection of starlight.
: Einstein was a co-leader in the birth and development of quantum mechanics
: Einstein and Bohr engaged in a fascinating series of "debates" over the interpretations of physics especially the notion of determinism (God does not play dice)
: Einstein searches for a unified theory of the universe
Hubble and Humanson discover the recessional nature of galaxies - Einstein's theories of the universe take shape.
1955: Einstein dies, Princeton, N.J.

50. Einstein’s Response to the Uncertainty Principle
1. Imagine a box with a hole and a shutter that contains radiation.
2. Let the shutter be opened for a time T such that one photon passes through the hole.
3. The box may be weighed before and after the event so the photon’s mass may be determined.
4. From E = mc2 the energy of the photon may be determined.
5. Since there is no uncertainty in the energy of the photon the product of the uncertainties in energy and time is zero (or as small as one likes).
6. This violates the time-energy uncertainty relation. From: Einstein, Bohr and the Quantum Dilemma

51. Einstein’s Thought Experiment
From: Einstein versus Bohr, Mendel Sachs

52. Bohr’s Response
It was quite a shock for Bohr… he did not see the solution at once.
During the whole evening he was extremely unhappy, going from one to the other, and trying to persuade them that it couldn’t be true. That it would be the end of physics if Einstein were right; but he couldn’t produce any refutation…
The next morning came Bohr’s triumph. Quote by Rosenfeld in Einstein, Bohr and the Quantum Dilemma

53. Bohr’s Response
According to general relativity, a clock which is moved in the direction of a gravitational field will change its rate. Thus the uncertainty in the position of the pointer, and hence of the box, gives rise to an uncertainty in the time interval. The uncertainty in momentum corresponds to an uncertainty in energy, and when the detailed sums are done, one obtains the result that the product of time uncertainty and the energy uncertainty is at least as great as … the time-energy uncertainty principle.
Quote by Rosenfeld in Einstein, Bohr and the Quantum Dilemma