Transcript Precursors to Modern Physics

Precursors to Modern Physics
1.
2.
3.
4.
5.
6.
Introduction to the course.
Quiz 0, one hour.
Required to read in the text book.
Class discussion.
Preview for the next class.
Homework 1.
Introduction

Course webpage:
http://www.physics.smu.edu/yejb/teaching/3305_2008f/3305.htm



How should we learn, a discussion in class.
Research in the real frontier of physics and technologies. And how that benefit
my teaching.
A little bit of the history (1):




Antiquity: mostly philosophical and mathematical discussions.
Physics in Middle Ages: many physics concepts like gravity, momentum started to
form.
Early modern or classical physics: mid 16th to late 18th centuries: physics as a science
was well established by experimental measurements and observations with solid
theoretical models. Newton, Maxwell, Bernoulli and many others. Foundation for
many other fields in science. The first industrial revolution.
Modern physics:



19th century: great success of the classical physics until Thomson (electron) and Lenard
(photoelectric effect). From almost all-known to a few “big troubles”.
20th century: the revolution in physics. Quantum mechanics to the very small and Special
Relativity to the very fast. Modernized many other fields in science, created many new
science fields. The second, and maybe the third industrial revolution.
21st century: getting into even more unknowns: atlas.ch.
(1) http://en.wikipedia.org/wiki/History_of_physics#Early_modern_physics
SMU supported URA projects
at the Physics research lab




Study on timing and spatial resolution of GPS units for
coincidence measurements off-line. This may lead to a
publication.
Development of a new instrument on multi-channel optical
power measurement with data logging capability for fiber optics
studies. This work will develop an instrument that is not available
on the market.
Study on an optical readout scheme of the Gas Electron
Multiplier (GEM) device. This work is part of our research
project in a study for solar neutrinos experiment for the US
Deep Underground science and Engineering Laboratory
(DUSEL).
If interested, talk to me after the class.
Required to read in the text book

Chapter 1, from page 1 to page 4.

Starting from next class, preview is required.
Reading and studying the required
chapters/sections in the text book is very
important to this course and to your final grade.
Class discussion


A review on PHYS 1303, 1304 on the
blackboard.
A glimpse into modern physics and its
importance in science, engineering and our
everyday life.
Preview for the next class

Text to be read:

In chapter 2:




Section 2.1
Section 2.2
Section 2.3
Questions:




What is time dilation, what is length contraction?
Can you propose a practical way to demonstrate time dilation?
Muon particle in cosmic rays are produced in upper atmosphere layers about 16
kilometers above sea level. They have a lifetime of 2.2 micro-second. If the
muons travel at a speed of 0.99c towards the Earth, can they reach the sea level?
If so, how much time you think the muon takes for this journey? What is the
distance the muons “think” they cover before they hit the waters?
What causes a supersonic boom? What causes the Cerenkov radiation? Cerenkov
radiation is a fact and is widely used in particle physics research. Does this mean
that Einstein’s second postulation for special relativity is wrong?
Homework 1
1.
2.
3.
4.
Who invented the Calculus and for what?
Quantum theory is needed in many industries. Name
one that we now cannot live without.
Relativity theory is not only needed in scientific
research labs, but also in some instruments we now
use in our everyday life. Give one example (one
instrument) where calculations in general relativity are
necessary.
Who invented the World Wide Web and where it was
invented?