Niels Martens Why Philosophy of Physics is Awesome!
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Phil of Physics Quantum (info) Thermodynamics/ Statistical
Mechanics Space, Time & Spacetime Specific sciences Phil of
Biology Phil of Mind Phil of Physics Phil of Mathematics Philosophy
of Science Epistemology Scientific method Specific sciences
(Anti)-realism Metaphysics
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Oxford Philosophers of Physics
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Philosophy of Space Is space real? Einsteins Relativity Theory
Time slows down! Space contracts! Cosmology/Big Bang Emergent
Space(time)
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Leibniz-Clarke Correspondence Space exists! It makes sense to
talk about empty space Even if there is no play tonight, the
theatre is still there All talk about space is reducible to talk
about relations between particles Compare with family relations
Newton Clarke Leibniz SUBSTANTIVALISMRELATIONALISM
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`Leibniz shifts: space must be relational
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`Newtons bucket: lets look at science! The relative motion
between bucket and water is the same in picture 1 and 3, but the
relative motion with respect to the stars is not! Problem: physics
becomes nonlocal Ernst Mach
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Lets use your left and right hands Immanuel Kant There is a
difference between your right and left hand The relationalist
explains the different handedness of two objects via relations What
about a single hand in an empty universe? Earman Handed laws of
nature
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Philosophy of Quantum Mechanics
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Metaphysics: What does the world look like according to quantum
mechanics? Quantum information Probability/determinism/free
will
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Interpreting Quantum Mechanics Does light (and everything else
in the world) consist of particles? Or waves? Photo-electric effect
(Einstein Nobel Price): particles Double split experiment:
waves
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Double slit experiment
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Does the photon (light particle) go through both slits at the
same time? Can we measure which slit it goes through? Even if you
only send one photon through the slits, we still get an
interference pattern! Photons are waves (and electrons, and
protons) You cannot say that there is a localised particle that
goes through one of the two slits: there is a wave that goes
through both slits: the photon is in a SUPERPOSITION of going
through the left and the right slit at the same time
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This is absurd! So, at the smallest scale, our world consists
of quantum waves: light, electrons, protons, everything is a
quantum wave, meaning that the `particles are at several places at
the same time. Schrdinger (Magdalen College Alumnus): This cannot
be true. If it would be true, it should also apply to large objects
(since they are made up out of small objects), and it would be
absurd to have a large object - like a table - being here and
somewhere else at the same time! We never see tables in
superpositions!
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Schrdingers cat
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Ways out Instrumentalism Measurement `collapses the
wavefunction If you measure with a big apparatus, you will find the
particle or cat in one specific place: the probability of that
place depends on how large the wave is at that point. Consciousness
`collapses the wavefunction Pilot-wave theory Many-worlds
interpretation
