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Note: Lectures will begin Monday Jan10 2022. 12:30 on Zoom. email unruh@physics.ubc.ca for zoom logon particulars.

- Talk to your students early in course about cheating - what it is, why they should not do
it, and even though it is easier to do it now, it is easier to catch as all the necessary
evidence is readily available.
- Be explicit and detailed about integrity expectations in your posted course outline and exam
instructions
- Tell students what happens if they are suspected of cheating:
- Interview with instructors and undergraduate chair, and if response is unsatisfactory -
- Zero on course component (e.g. exam) and report sent to Dean's Office, then -
- Interview with the Associate Dean, then -
- At least: Letter of reprimand on permanent file
- More serious cases and all second offences: Move to President's Disciplinary Committee, with consequences up to and including expulsion

- Interview with instructors and undergraduate chair, and if response is unsatisfactory -

- Tell students what happens if they are suspected of cheating:

- Be explicit and detailed about integrity expectations in your posted course outline and exam
instructions

Final Exam The existence and structure of the final exam is still open for decision/discussion. I will let you know via email what the decision is.

- Review of Quantum Mechanics
- Complementarity,Entanglement,Delayed Choice,
- Bell's Thm, Hardy's System, and the difference between quantum theory and Classical theory.
- Conditions in QM (Aharonov's study of setting conditions at past and future times)
- Linear Quantum Field theory (Bosonic theories, Simple Harmonic Oscillator, squeezed states)

- Particles and Detectors
- Hawking Radiation and Bugoliubov
- Application to quantum noise in Ligo
- Introduction to Quantum Computing (Grover, Shor, and Quantum bit operation diagrams
- ....

- Heisenberg Schroedinger representations, an expmaple of going from Heisenberg to Schroedinger, Unitary evolution and Magnus expansion. Corrections Jan 11 2021
- Unitary transformation, Interaction representation, Example of use of representations.
- Entanglement, density matrix and measurement model
- Density Matrix
- Complementarity, delayed choice, quantum eraser (Ch 8 from Zubairy's new book "Quantum Mechanics for beginners")
- Bell's Thm, Hardy's system, and Quantum Mechanics
- Heisenberg from 1930--
**The Physical Principles of Quantum Mechanics**The uncertainty principle refers to the degree of indeterminateness in the possible present knowledge of the simultaneous values of various quantities with which the quantum theory deals; it does not restrict, for example, the exactness of a position measurement alone or a velocity measurement alone. Thus suppose that the velocity of a free electron is precisely known, while the position is completely unknown. Then the principle states that every subsequent observation of the position will alter the momentum by an unknown and undeterminable amount such that after carrying out the experiment our knowledge of the electronic motion is restricted by the uncertainty relation. This may be expressed in concise and general terms by saying that every experiment destroys some of the knowledge of the system which was obtained by previous experiments.

This formulation makes it clear that the uncertainty relation does not refer to the past: if the velocity of the electron is at first known and the position then exactly measured the position for times previous to the measurement may be calculated. Thus for the past times �~Tx�~Tp is smaller than the usual limiting value, but this knowledge of the past is of a purely speculative character, since it can never (because of the unknown change in momentum caused by the position measurement) be used as an initial condition in any calculation of the future progress of the electron and thus cannot be subjected to experimental verification. It is a matter of personal belief whether such a calculation concerning the past history of the electron can be ascribed any physical reality or not.

- Einstein, Richard Tolman, and Boris Podolsky, Knowledge of Past and Future in Quantum Mechanics. Phys Rev D 37 780-781 (1931)
- Two time conditions for a two level system.
- Aharonov Bergman and Lebowitz Time symmetric quantum mechanics.
- Weak Measurements and Weak Values.
- A series of movies showing what the effect is of decreasing the accuracy of the measurements for a two-time spin 12.5 system.
- How to measure the spin of a spin 1/2 particle and obtain a spin of 100
- Mean King Problem How to know what the value of sigma-x, sigma-y or sigma-z is of a two level system. "A procedure is described whereby the result of the measurement of any of the three Cartesian components of the spin of a single spin- —, particle at a single time can be inferred with certainty from the result of two other measurements, one of which is carried out before, and the other after, the time in question"
- Vaidman Bomb detector -- Or Interaction free Measurements
- Book-ch 4 This is a chapter from a book being written by R Schuetzhold and me.
- Norm for modes and associated Annihilation operators
- Norm and Frequency It is the norm of a mode, not its temporal frequency which determines which is associated with the Annihilation operators.
- "Assymptotic Adiabatic approximation for time dependent Harmonic Osciallator"
- A Simplified Landau Zenner derivation
- Particle creation by expanding Universe
- Interaction Representation and Detectors
- Accelerated Detector The calculation that an accelerated detector in the Minkowski vacuum state is excited at a thermal rate.
- Negative Frequencies, Cherenkov emission and squeezing
- Dispersion relation for superfluid liquid He When the velocity through the fluid becomes great enough to there is a region of wavenumber where the frequency becomes negative on a branch where the norm is positive. This allow quantum creation between modes with negitive frequency and positive norm (Annihilation operators) and the same negative frequency and negative norm (creation operators) giving mode mixing and pair creation. The difference in momentum is absorbed by the particle which implies a force on the particle.
- Unruh-Wald-- detection of a particle by accelerated detector and causality (PhysRevD.29.1047)
- Notes for recent talk to IQSE, Texas A&M on radiation and detector emission (small modifications Apr 8 2022)
- Recent paper on the detection by two detectors and paradoxical results thereof
- Amplifier model (interaction constants altered to agree with that used in lecture.-Mar 23)
- "popular talk on Gravitational radiation and the quantum Ligo detector"
- One of the very early papers (1979) on the quantum nature of gravitational wave detectors, including laser detectors.
- Laser Interferometer detection of force on a Mirror
- Handwritten notes on the effect of laser beam on radiation pressure quantum fluctuations on detector
- Caves 1980 PRL showing that radiation pressure fluctuations add noise to interferometer.
- Original paper on laser noise
- Noise in Interferometer Hand notes
- Notes on Quantum Interferometer II (some of this replaces the previos notes, and extends them)
- Hung Ou Mandel experiment
- Beamsplitter calc and Hung Ou Mandel effect
- quantum computing intro and Grover's algorithm
- First paper on Adiabatic Quantum Computing by Farhi et al.
- Varieties of Q Compting Hand written notes ( for an amplification of the Adiabatic thm derivation see HERE (altered Apr2-18:30 to include Berry's phase)
- Error Correction (Includes
diagramatic representation of Quantum Gates)

Error correction notes 2021 - Quantum Fourier Transform and Shor's algorithm
- Diagram of Fourier Transform
- Diagram of Shor Algorithm

If not handed in in class, put assignments into box on shelf outside my room (in 311 Hennings) labeled Phys 341. (Not into the metal sorting rack but into the box) The box is inside Rm 311 Hennings-- go right into the room up to the table, then turn right. The shelf is on your right. My office is straight ahead of you.

- Assignment 1 (Sun eve, Jan 16 2021-- I have simplified the problem slightly by choosing m=1 and Omega=1, and the delta function at t=0.
- Assignment 2 Misprints in assignment 1 eqn 1 corrected (Feb2) Due Feb 7 23:59
- Assignment 3 Because of Midterm Break, due Mon Feb 21 23:59
- Assignment 4 Due Mon, Mar 14
- Assignment 5 Due Wed Mar 30
## Solutions

- Solutions 1
- Solutions 2
- Solution 3 Some corrections Feb 23 14:00
- Midterm
- Solution 4
- Solution 5

Notes, solutions or documents linked to from this page and hosted on theory.physics.ubc.ca are copyright W. G Unruh. 2021-22 unless created by others