Transcript How Did Einstein Discover Special Relativity? Three Possible Ways

How Did Einstein
Discover Special
Relativity?
Three Possible Ways
John D. Norton
Department of History and Philosophy of Science
Center for Philosophy of Science
University of Pittsburgh
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Experimentally Driven Pathway
Reflections on certain puzzling experiments,
notably the Michelson-Morley experiment.
✗
Origins
Consequences
Oversimplified experimentbased pedagogy.
Excessive focus on the question: did
Einstein know about the MichelsonMorley experiment?
Oversimplified empiricist
philosophy of science.
Obliteration of most of the history.
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Philosophically Driven
Pathway
Reflections on what is really means to say that
something moves, that events are simultaneous,
etc. led to the theory.
Origins
Power of Einstein’s 1905 analysis of
simultaneity; logical simplicity of his
formulation.
Ease of comprehension of the
kinematical part versus the
electrodynamical part of Einstein’s
analysis.
✗
Consequences
Newton and Newtonians guilty of
just not thinking hard enough.
Excessive focus on where
Einstein may have found
inspiration for the light signaling
narrative used in 1905.
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Electrodynamically Driven Pathway
Special relativity can only emerge
once we have established the behavior
of systems that move very rapidly.
Newtonian theory based on
slowly moving bodies: falling
masses, planets, etc.
“On the electrodynamics of moving
bodies” resulted from seven and more
years of intense work by Einstein on
problems in electrodynamics; and it is
overtly about electrodynamics.
Maxwell’s electrodynamics is
the first theory to give reliable
accounts of things moving
very fast, e.g. light.
Special relativity is buried
in Maxwell’s
electrodynamics and awaits
someone to find it.
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Lorentz’s Theorem(s) of Corresponding States
A hard problem in
Newtonian physics.
Solved by its
satisfaction of the
principle of relativity.
Redescribe the
same system in
the rest frame of
planet.
Galilean
transformation
Alternative
description of
the same
system
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Lorentz’s Theorem(s) of Corresponding States
A hard problem in
electrodynamics.
Cannot be solved by the
principle of relativity.
Fails in electrodynamics.
Einstein: yes it can!
Einstein: a redescription
of the same system in
another frame of
reference.
Find closest, but
different, system in
the rest frame of the
charge.
A different system;
close in properties;
distorted;
“corresponding.”
Lorentz
transformation
Einstein: the
right way to
redescribe
systems in
different inertial
frames of
reference.
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