big bang, black holes, no math - texas a&m...
Post on 21-Feb-2021
19 Views
Preview:
TRANSCRIPT
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
1
Big Bang, Black Holes, No Math
ASTR/PHYS 109Dr. David Toback
Lecture 4
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
2
Prep For Today (is now due) – L4If you just joined the class, welcome. Send me an email if you need an extension. All this is posted in the lecture notes!!• Reading:
– BBBHNM Unit 1 (Chapter 1-4): Was due already – Recommended Reading (not required): BHOT: Chap. 1-3, SHU: Chap. 1-
2, TOE: Chap. 1• eCampus Stuff
– (Warm-up Quizzes Parts 1 & 2)– Warm-up Quiz Part 3 (Requirements): Was due before class– Extensions granted if needed. 109QuizHelp@Physics.tamu.edu
• Pre-Lecture Reading Questions:– Unit 1 Quizzes:
• Two parts A & B. Will assign today• Will open after you finish Warmups Parts 1-3.
• End-of-Chapter Quizzes:– End-of-chapter quizzes 1 and 2: Was due before class
• Honors Section:– Start working on Stage 0. Need to hear from you at least once every 7
days
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
Next Topic: Going Small• Finished looking at various things in the universe going from the sizes we know to the VERY big
• Next we do the very small• Why? If we want to understand the universe we need to know what’s in it and what its made of
• Then we can get to the “Why and how did it get to be the way it is?” 4
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
5
Starting out with small things
10 centimeters, or 0.1 meters, or 10-1 meters.About 3 inches
A baseball is a size we know from everyday experience
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
6
Getting smaller
Something smaller you can see with your eyes
0.01 meters, (10-2 m) or 1 cm, or about a 1/3 of an inch
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
7
Much smallerA simple dust mite is barely visible with the naked eye
Into the realm of biology10-3 metersor 1 millimeter
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
8
A human hair
Looking at the side view of a single hair
10-4 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
9
Closer still…A single red blood cell
10-5 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
10
Further still
An HIV virus which is one of the bigger known viruses
10-6 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
11
Small VirusA polio virus which is known to be one of the smaller viruses
10-7 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
12
The Double HelixA close up of the helical structure of DNA
Starting to get into Chemistry
10-8 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
13
An Atom
10-9 meters or 1 nanometer
10 million in a cm
•What we’re seeing is the electron “cloud” as it goes around the atom• Kinda like the blades of a fan
•The realm of Physics
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
14
Inside an Atom
•Snapshot in time of 2 electrons “orbiting” the nucleus
•Atoms are “composite” things, not fundamental
10-10 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
15
The Central Part of the Atom• The electrons are outside our field of view
10-11 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
16
Homing in on The Nucleus• Still zooming into the center of the atom
• The atom is mostly empty space
10-12 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
17
The Structure of the NucleusCan just start to see the “stuff” inside the nucleus
The nucleus is not fundamental
10-13 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
18
Protons and Neutrons• A carbon atom has 6 protons (blue) and 6 neutrons (grey)
• VERY tightly packed
10-14 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
19
Inside the ProtonThree quarks inside the proton–Protons are composite
–Quarks are fundamental
10-15 meters
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
Other Fundamental Particles?• Electrons and quarks (as far as we know) are fundamental
• Lots of other fundamental particles
• Recently discovered the Higgs Boson
20
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
Anti-Matter Each fundamental particle has an anti-matter
version which is also fundamental
21
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
22
Protons are stable live foreverNeutrons outside a nucleus are unstable
can decayNeutron Proton + Electron + Neutrino
Stable and Unstable Particles
Neutron
ProtonDecay Electron
NeutrinoNote that this only happens when Neutrons
are by themselves (not in an atom)
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
23
Questions…
• How large are electrons and quarks?–We don’t know… that’s what I (and others) do for a living…
• Are we SURE they are fundamental? Could they made of something smaller? Strings?
• Are there other fundamental particles we haven’t discovered?
IntroductionTopic 3: Going Small
Big Bang, Black Holes, No Math
Lecture on Chapter 3 now complete
24
IntroductionTopic 4: Scientific Methods
Big Bang, Black Holes, No Math
Next Topic: Scientific MethodsUnit 1:1. Introduction Done2. Going Big Done3. Going Small Done4. Evidence and the Scientific
Method TodayToday we move on to the Questions
and How we go about answering them
3
IntroductionTopic 4: Scientific Methods
Big Bang, Black Holes, No Math
4
Plan for the Next Few Weeks1. More on the Questions
and How we go about answering them
2. Some of the history to teach us about the method
3. Need to learn some physics
Today
} Unit 2 (Chapters 5-9)
IntroductionTopic 4: Scientific Methods
Big Bang, Black Holes, No Math
5
Next few Weeks Continued… The tools in our toolbox… Learning some PhysicsTo learn Cosmology will need to learn a bit about:1. Light and Doppler Shifts 2. Gravity, General Relativity and Dark
Matter3. Atomic Physics and Quantum
Mechanics4. Nuclear Physics and Chemistry5. Temperature and Thermal Equilibrium
Won’t spend too long on these, just enough to get back to the big picture…
IntroductionTopic 4: Scientific Methods
Big Bang, Black Holes, No Math
Prep For Next Time – L4If you just joined the class, welcome. Send me an email if you need an extension. All this is posted in the lecture notes!!• Reading:
– BBBHNM Unit 2 (Chapters 5-9):– Recommended Reading:
• See P3 of http://people.physics.tamu.edu/toback/109/Syllabus.pdf• eCampus Stuff
– (Warm-up Quizzes Parts 1-3)– Warm-up Quiz Part 4 (Peerceptiv): Will assign next time– Extensions granted if needed. 109QuizHelp@Physics.tamu.edu
• Pre-Lecture Reading Questions:– Unit 1 Quizzes: Two parts A & B: Due before next class
• Will open after you finish Warmups Parts 1-3– Unit 2 Text Submission: Not yet assigned
• Submit to TurnItIn on eCampus. • Submit ONLY 4 questions, need all 4 to be excellent to pass• Pass/Revise assignment. If you don’t pass we will set up dates for Revisions after you get Feedback
– Unit 2 Quiz: Not yet assigned• End-of-Chapter Quizzes:
– Chapters 1-3• Honors Section:
– In a heavy reading stage, submit a draft of Stage 0, if you haven’t yet. Need to hear from you at least once every 7 days
28
top related