1. 1905 – The Miracle Year in Physics
Annus Mirabilis
1905 – The Miracle Year in Physics
Christian Educators Annual Fall Conference
October 2005
Dr. Brian Martin – The King’s University College, Edmonton

2. From March to September 1905, Albert Einstein published 5 papers that have transformed physics in profound ways…
March
April
May
June
September

3. (Annalen der Physik 17:132-148)
March 1905…
“On a Heuristic Point of View Concerning the Production and Transformation of Light” 
(Annalen der Physik 17: )

4. This was the paper Einstein consider his most radical!
March 1905
This was the paper Einstein consider his most radical!
In the paper he puts forward the quantum of light hypothesis – he suggests light may be a particle! Consider the opening lines of his paper…

5. March 1905
THERE exists an essential formal difference between the theoretical
pictures physicists have drawn of gases and other ponderable
bodies and Maxwell’s theory of electromagnetic processes in
so-called empty space. Whereas we assume the state of a body to
be completely determined by the positions and velocities of an,’
albeit very large, still finite number of atoms and electrons, we use
for the determination of the electromagnetic state in space con-
tinuous spatial functions, so that a finite number of variables
cannot be considered to be sufficient to fix completely the electro-
magnetic state in space. According to Maxwell’s theory, the
energy must be considered to be a continuous function in space
for all purely electromagnetic phenomena, thus also for light,
while according to the present-day ideas of physicists the energy
of a ponderable body can be written as a sum over the atoms and
electrons. The energy of a ponderable body cannot be split into
arbitrarily many, arbitrarily small parts, while the energy of a
light ray, emitted by a point source of light is according to
Maxwell’s theory (or in general according to any wave theory) of
light distributed continuously over an ever increasing volume.

6. March 1905
Helped to explain the photoelectric effect and was the work for which he was eventually awarded the Nobel Prize (1922)
Established light as a quantum of energy – led to the
wave-particle duality that is central to quantum mechanics.
Impact...

7. April 1905… "The Determination of Molecular Dimensions".
(Annalen der Physik 19: )

8. Provided a novel way to determine Avogadro’s number
April 1905…
Was Einstein’s Doctoral Dissertation (chosen because he judged it the least controversial and several of his more radical ideas had already “failed” as PhD dissertations!)
Provide a theoretical means to determine the sizes of molecules at a time when a significant number of scientists – including some of the greatest – doubted the “atomic theory”
Provided a novel way to determine Avogadro’s number
Provided an essential first step to his May 1905 discussion of Brownian Motion.

9. Impact... April 1905 One of the first theoretical methods to determine
the sizes of molecules and atoms.
Impact...

10. (Annalen der Physik 17:549-560)
May 1905
On the Movement of Small Particles Suspended in Stationary Liquids Required by the Molecular-Kinetic Theory of Heat" 
(Annalen der Physik 17: )

11. May 1905
Applied the methods of statistical mechanics to explain the phenomenon of Brownian Motion. demo of Brownian Motion
Provided conclusive evidence for the atomic theory and the existence of atoms.

12. Impact... May 1905 Provided an almost iron-clad demonstration of
the existence of atoms. Considered to be one
of the truly great papers of the early 20th Century.
Impact...

13. June 1905… "On the Electrodynamics of Moving Bodies"
(Annalen der Physik 17: )

14. The laws of physics are the same for all uniformly moving observers.
June 1905…
Forever changed our understanding of space, time and their interrelation
Introduces the concept of spacetime and develops the Theory of Special Relativity
The mystery of ‘c’ and the two postulates of Special Relativity
The laws of physics are the same for all uniformly moving observers.
The speed of light is the same for all observers.

15. How Einstein changed our understanding of space and time…
The odd result of the Michelson-Morley Experiment
The problem of simultaneity
Time is not absolute
Lorentz-Fitzgerald Contraction

16. Impact... June 1905 Introduced the Special Theory of Relativity and
irrevocably changed our understanding of space
and time.
Impact...

17. September 1905…
"Does the Inertia of a Body Depend upon its Energy Content?“
(Annalen der Physik 18: )

18. September 1905…
Introduced the “most famous equation in the world” through a very simple argument
E = mc2

19. Established the fundamental unity between matter and
September 1905
Established the fundamental unity between matter and
energy.
Impact...

20. Einstein in the Curriculum
The main ideas of special relativity can be taught with the minimum of mathematics. You don’t need to feel like a “yo-yo”!

21. Einstein can be Simplified!

22. Einstein Simplified…

23. A closer look at …
Simultaneity
The concept of spacetime
Mass – energy equivalence

24. Copy of talk available at:
The End! Questions?
Copy of talk available at:
chris.kingsu.ca/~brian/talks/cea2005/einstein/Annus Mirabilis.ppt

25. Problem with simultaneity…
Sam and Sally have a dispute! Sam is riding in the middle of a
long train moving due east while Sally is sitting close to the
tracks on the train platform. At the exact instant that Sam passes
Sally, two lightning bolts strike each end of the train. Both Sam
and Sally see the bolts at the same instant. Scorch marks
are left on both the track and the train to prove it happened!
Sam concludes that they must have occurred simultaneously.
He remarks to Sally when they next meet how
improbable that was. Sally retorts that they weren't simultaneous at all,
and that she can prove it! Who is correct?