Absolute Acceleration

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Absolute Acceleration Newtons Rotating
Arguments ?????????????

• Does the theory of absolute space really have no
  empirical relevance?
• Relative acceleration (both magnitude
  direction)
• Rate of change of relative velocity
• Absolute acceleration (both magnitude
  direction)
• Rate of change of absolute velocity
• Acceleration relative to absolute space
• Any empirical interpretation for absolute
  acceleration?

2

• Consider
• Their mutual relative accelerations are
  symmetric.
• Is it empirically meaningful to say that only one
  of them is absolutely accelerating? Any
  distinguishing feature?

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• Newtons rotating spheres
• - After steady rotation is generated, tension
  exists in the cord.
• Why such tension?
• Imagine the possibility of its absence.
• - Newtons insight
• The tension is to overcome the inertia (??) so as
  to generate absolute acceleration.

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• - What is inertia?
• Inertia state (????) of objects maintained by
  absolute space moving with constant velocity
  (including v0) wrt absolute space.
• To disturb inertia state, i.e. to make absolute
  acceleration, an external force is needed.
• - So, inertia effects (????) like the tension
  can be an empirical indicator of absolute
  acceleration, and hence absolute space.

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• - But can inertia effects be construed in
  relationist terms?
• - In particular, can the tension be construed
  under any rotation relationships?
• Rotation relative to the observer?
• What if the observer runs around the spheres? Any
  tension?

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• Rotation relative to the rest of the Universe?
• Force from the heavens?!
• Vs. local interaction with absolute space.

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• Newtons rotating bucket

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• - Inertia effect - concave water surface
• Similar reasoning leads to the postulation of
  absolute space and its effect.

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• - How about relationism?
• Rotation relative to the bucket does not produce
  the inertia effect.
• Stage 2 relative rotation yes inertia effect
  - no
• Stage 3 relative rotation no inertia effect
  yes
• Rotation relative to the rest of the Universe?
• Similar criticisms.
• - Newtons general point against relationism
• There are empirical effects that seem
  incomprehensible in relationist framework.

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Objections Developments ?????

• Leibniz
• Died during the correspondence, and did not give
  a clear response to Newtons rotating arguments.
• Admitted absolute acceleration, yet denied that
  it is related to absolute space, but to whether
  the immediate cause of the change is in the body
  itself.
• Absolute motion without relative to absolute
  space? Absolutely absolute motion?
• E.g. Sklars (1974) idea of absolute motion as a
  brute fact of the object

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• Ernst Mach
• An extreme relationist
• A dispute on rotating in an immense void
• Newtonian Conceivable. Tension still exists.
• Machian Inconceivable. No tension.
• What do you think?

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• Albert Einstein
• Is Einsteins theory of relativity (???) for
  relationism and against absolutism?
• The situation is complicated . . .
• Misleading name? Einsteins theory of absolute
  (???)?
• Problems / positions redefinition spacetime as
  an integrated unit for consideration. Exactly how
  to define? E.g. spacetime substantivalism.

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• Maybe for relationism and against absolutism
• E.g. the relativity of simultaneity (???????)
• Maybe for absolutism and against relationism
• E.g. Einsteins theory requires an absolute
  standard of constant motion. Is this absolute
  space? Still debating.
• One more remark related to spacetime
• The dynamical conception of spacetime dissolved
  an inconsistency in Newtons theory.
• The inconsistency between Newtons 3rd Law and
  the assumption that only absolute space has
  effect on matter.

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Readings References

• Readings (selections from the Stanford
  Encyclopedia of Philosophy read those you find
  interesting and understandable)
• Absolute and Relational Theories of Space and
  Motion
• http//plato.stanford.edu/entries/spacetime-theori
  es/
• Gottfried Wilhelm Leibniz
• http//plato.stanford.edu/entries/leibniz/
• Leibniz on Space and Time in Leibnizs
  Philosophy of Physics
• http//plato.stanford.edu/entries/leibniz-physics/
  LeiSpaTimSec

Most relevant
Leibniz
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• Issac Newton
• http//plato.stanford.edu/entries/newton/
• Newton's Philosophiae Naturalis Principia
  Mathematica
• http//plato.stanford.edu/entries/newton-principia
  /
• Newton and Leibniz in Newtons Philosophy
• http//plato.stanford.edu/entries/newton-philosoph
  y/NewLei
• Newton's Views on Space, Time, and Motion
• http//plato.stanford.edu/entries/newton-stm/

Newton
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• The Hole Argument (an argument against
  spacetime substantivalism)
• http//plato.stanford.edu/entries/spacetime-holear
  g/
• Space and Time Inertial Frames
• http//plato.stanford.edu/entries/spacetime-iframe
  s/
• References
• Huggett, N. (ed., 1999). Space from Zeno to
  Einstein Classic Readings with a Contemporary
  Commentary. Cambridge, Mass. MIT Press.
• Sklar, L. (1974). Space, Time, and Spacetime.
  Berkeley University of California Press.

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