Quantum Theory
The worst scientific theory of
all time
Dr Mark J Hadley
Dept of Physics
Plan
• Introduction to QT
• Why it is bad
• A bad theory of classical Mechanics
– Classical probability
• Why the quantum world is different
– Why QT is a bad response
• An alternative to QT
Quantum theory
• Predictions are intrinsically probabilistic.
• A state is represented by a vector, , in a
complex Hilbert space.
•  contains the maximum possible
amount of information.
• A rule to get probabilities from .
• A rule to describe the evolution of .
Includes
• Quantum mechanics
• Quantum Field Theory
• String Theory
How bad?
1.
2.
3.
4.
5.
Quantum Theory
Genesis
..
.
.
Why is it so bad?
• Fails to explain Nature
– What is an elementary particle
• Particle spectrum
• Fundamental forces
– What is happening in an experiment
• Prevents progress
(x)
•
•
•
•
•
Gives probability information only.
It is not the particle.
It does not exist.
It requires a new meaning to probability
Cannot say what a particle is..
• where it is…
• what it is doing.
A bad theory of classical
mechanics
• Throwing a projectile at a target.
• (r,) describes the probability of a
certain result.
• (r,,z,t) describes the evolving wavepacket.
• Nothing else can be said about the
projectile
A dice throw
• (n) gives the probability of a particular
result.
• The throw is governed by classical
mechanics.
• (n) = 1/6
• Why?
(n)

0.25
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0
0.2
0.15
0.05
0
1
2
3
4
5
1
6
0.25
2
3
4
5
high
6
0.6
0.5
0.2


0.1

0.4
0.15
0.3
0.1
0.2
evens
0.05
0.1
0
0
1
2
3
4
5
6
1
2
3
4
5
6
lucky
(n)= 1/6
• Not from Newtonian mechanics
• Structure
Phase space of initial conditions
+ Deterministic evolution
= Space of final conditions
• Symmetry
• Nothing else
Structural Implications
Deterministic evolution
Phase-space of initial
conditions
(n)
Boolean Logic
1
2
3
4
5
6
Classical Probabilities
• Satisfy Boolean Logic
• Are a measure of our ignorance of initial
conditions.
• Can always be represented as Volume
integrals.
Quantum Theory Probabilities
• Do not satisfy Boolean Logic
• Are represented by projections of a
vector
• Are an intrinsic feature of Nature
A completely new meaning to probability
Classical and Quantum worlds
are very, very similar.
For a single experiment
– Can use classical probabilities
• Boolean Logic
• Individual trajectories
• No complex wave function
For incompatible experiments
– Cannot construct a single phase-space of initial
conditions that gives the observed results.
The quantum World is context dependent
• QT is one response
– It hides the difference
• State => Evolution => results
– At a cost
• A new meaning to probability
• No underlying explanation
The quantum World is context dependent
• Explain it with an existing theory
– Sensible
• Explain it with a brilliant new theory
– Genius
• Don’t explain it
– Pragmatist
• Deny that anything needs explaining
– Philosopher
The quantum World is context dependent
• Explain it with an existing theory
– lazy
• Explain it with a brilliant new theory
– insane
• Don’t explain it
– loser
• Deny that anything needs explaining
– bad loser
Using an existing theory
•
Choice between:
1. GR
2. GR
3. GR
GR and QT
• Can GR explain context dependent
effects?
– Yes
• Will it agree with QT predictions?
– Yes it has to
Structure + Symmetry & Continuity
= all equations of QT
Using GR
• GR allows a non-trivial causal structure
– Measurement apparatus can set additional
boundary conditions
• Any Geometric theory of spacetime can
have the same structure
From GR to QT
• Can GR get the equations of QT
directly?
– No (Not yet)
– But remember (n)= 1/6
Progress
The Logic of Quantum Mechanics Derived From Classical
General Relativity
Foundations of Physics Letters Vol 10, No.1, (1997) 43-60.
• Topology change and context dependence
International Journal of Theoretical Physics Vol. 38 (1999) 1481
• Charge and the topology of spacetime
Class. Quantum Grav. 16 No 11 (November 1999) 3567-3577
• Spin half in classical general relativity
Class. Quantum Grav. 17 No 20 (October 2000) 4187-4194
• The orientability of spacetime
Class. Quantum Grav. 19 (August 2002) 4565-4571
The Quantum World
• Explain it with an existing theory
– GR (sensible)
• Explain it with a brilliant new theory
– insane
• Don’t explain it
– loser
• Deny that anything needs explaining
– Quantum Theory (bad loser)