# Meetings 2019

[ Past Meetings ]

### Eduard – Quantum phase kickback

Eduard discussed Quantum Phase Kickback, which is an important part of Deutsch, Simon, Shor, Grover and phase estimation quantum algorithms.

Here are the notes: https://eduardsmetanin.github.io/PhaseKickback.pdf

### Aug 18th: Stefan – Maxwell’s Equations

Attending: Jonathan, Mike, Scott, Stefan

Today Stefan did a presentation on (the non-relativistic version of) Maxwell’s Equations.

### August 4th: GR#7 – More on Acceleration

Attending: Jonathan, John, Mary Ann, Mike, Scott, Stefan

### July 21st: GR#6 Constant Acceleration

The plan is to look at constant acceleration. First in SR and then as a metric in GR. Susskind covers this in Lecture 4, starting around 45 minutes. I will try to understand what he did well enough to explain it.

The following notes were passed around during the meeting:

Additional note on July 23rd: I tried Stefan’s idea regarding the energy expended to accelerate the object. This amounted to making the distance from the starting point of acceleration (or, equivalently, moving the starting point to the origin). This didn’t change anything. I also took my best shot at using just the and from the Schwartzchild solution, and I ended up getting exactly the same (wrong) path. As to exactly what that implies is probably a subject for further discussion, as I would have expected these paths to be different as they approached the mass.

### July 7th: GR#5

Attending: John, Jonathan, Mike, Stefan

This was a fairly low-key meeting. We reviewed the formulas for the Covariant Derivative, the Christoffel Symbol and the Geodesic Equation. We discussed some questions from material previously covered.

### June 9th: GR#4 Collier chapter 6

I don’t have a lecture prepared for today. What I anticipate happening is more of a group discussion of Chapter 6. So please bring your book!

### May 12th: GR#2 Tensor Math I

Attending: Eduard, John, Jonathan, Mary Ann, Mike, Scott, Stefan
References: (1) Collier chapter 5, (2) The big picture, (3) May 12th notes

### April 28th: GR#1 Scott covered chapter 4 of Collier

Attending: Eduard, Mike, Scott, Stefan, Tina
Chapter four is fairly brief. If you didn’t make it today please take a look at it.

April 21st: Easter / No Meeting
Note that we’re changing to “even weeks” now!

### April 7th: First look at Tensors

Attending: Eduard, Jonathan, John, Matt, Mike, Scott, Stefan, Tina
References: (1) Implicit Summation (2) First look at Tensors

### March 24th: SR#6 Four Vectors

Attending: Eduard, Jonathan, John, Mary Ann, Matt, Mike, Stefan, Tina
Continuing “four-vectors” …
For anyone who missed last time or who wants something else that has a bit more detail than the book, this lecture is pretty good.

### March 10th: SR#5 Four Vectors

Attending: Jonathan, John, Matt, Mike, Stefan, Tina

We derived the formula for addition of velocities and started talking about “four vectors” which are special relativity’s analog to things like position, velocity, momentum, and so on. We covered position and velocity.

### February 24th: SR#4 The Relativistic Snake

Attending: Eduard, Jonathan, John, Mary Ann, Matt, Mike, Scott, Stefan, Tina

Tina presented the “relativistic snake” problem as described in John Taylor’s Classical Mechanics book.
We also spent some more time on the “horizontal light clock” that John brought up last time we met. This has turned out to be a very good example from various perspectives.
Here are some diagrams that might come in handy:
lab-frame.png,
snake-frame.png,
clock-frame.png,
observer-frame.png

### February 10th: SR#3 The Lorentz Transformation

Attending: Eduard, John, Mary Ann, Matt, Mike, Stefan
– The transforms
– Spacetime Diagrams
– Relativity of simultaneity
– John brought up an interesting scenario with a horizontal light clock.

### January 27th: SR#2 Tina did Time Dilation and Length Contraction

Attending: Eduard, John, Mary Ann, Matt, Mike, Scott, Stefan, Tina
The group also worked several of these problems

### January 13th: SR#1 Introduction

Attending: Eduard, John, Mary Ann, Mike, Scott, Stefan
– Notions of relativity before Einstein
– Postulates of Special Relativity / preview of their consequences.
– We used These Notes