Lecture #2: Origin of Particles & Fields

Question 1

what is quanta?

Answer 1

discreet energy packets emmitted by electromagnetic waves

Question 2

How can electromagnetic waves be emmited?

Answer 2

ONLY in quantized forms known as quanta

Question 3

What is light’s dual nature?

Answer 3

consists of photons (discrete bundles of energy) and behaves like electromagnetic waves

Question 4

What does an atom consist of?

Answer 4

nucleus and electrons moving around nucleus

Question 5

What particles do the nucleus of atoms contain?

Answer 5

protons and neutrons

Question 6

what do you call protons and neutrons collectively?

Answer 6

Baryons

Question 7

every particle has an associated wave proportional to what?

Answer 7

it’s mass! (de broglie wave)

Question 8

What is a Field?

Answer 8

a physical quantity that has a value at each point in space and time filled with energy and momentum.

Question 9

true or false: field can be considered as collection of particles

Answer 9

true

Question 10

Is the energy in a field quantized?

Answer 10

yes.. and the quantization can manifest itself as a particle

Question 11

How do particles in a field interact?

Answer 11

• emiting a virtual particle that’s absorbed by the other particle

Question 12

what is a virtual particle?

Answer 12

particle w/ extremely short lifetime

Question 13

How do 2 electrons interact through electromagnetic force?

Answer 13

by exchanging a virtual photon and making the other photon responsible for the electromagnetic forces

Question 14

what do you call a force carrying particles that mediate interactions ?

Answer 14

Bosons

Question 15

what do you call particles that form the matter around us?

Answer 15

leptons and quarks

Question 16

What are the 3 groups particles in nature can be divided into?

Answer 16

quarks, leptons, and force carrying particle (bosons)

Question 17

what are the most fundamental particles?

Answer 17

quarks and leptons

Question 18

how do quarks and leptons interact w/ each other?

Answer 18

by exchanging bosons

Question 19

What 2 forms are matter in?

Answer 19

hadrons and leptons

Question 20

Do hadrons or leptons consist of quarks?

Answer 20

hadrons

Question 21

Depending on the spin of particles, where are they divided into?

Answer 21

fermions or bosons

Question 22

_____ is the bulk of the matter in the universe

Answer 22

fermions

Question 23

what particles keep quarks together?

Answer 23

gluons

Question 24

What colors are quarks assigned?

Answer 24

red, blue, and green

Question 25

true or false: quarks are bound together by strong interaction?

Answer 25

true

Question 26

What 2 types do leptons consist of?

Answer 26

electrons and neutrinos

Question 27

How many forces in nature and what are they?

Answer 27

4; gravity, electromagnetism, weak and strong

Question 28

What is Gravity force?

Answer 28

- holds planets and stars together - effective at large distances

Question 29

What is electromagnetism force ?

Answer 29

- stronger than gravity - depends on particles electric charge

Question 30

What are strong and weak force ?

Answer 30

- operate over short distances of atomic size - strong: binds atom nucleus together - weak: responsible for nuclear reactions (fission and fusion)

Question 31

how many quarks do protons and neutrons have each?

Answer 31

3

Question 32

what type of protons do free neutrons decay to?

Answer 32

protons emitting an electron and a neutrino

Question 33

what force mediated by gluon particles keeps neutrons and protons in the nucleus and quarks in neutrons and protons?

Answer 33

strong

Question 34

what force meditated by W and Z particles is responsible for decay of particles ?

Answer 34

weak

Question 35

what force is mediated by photons?

Answer 35

electromagnetic

Question 36

what force is likely mediated by gravitons?

Answer 36

gravity

Question 37

what is higgs field?

Answer 37

- fills all of space - gives particles properties they have

Question 38

mass of particles are result of what?

Answer 38

the interaction of those particles with w/ the higgs field via higgs boson

Question 39

where does the higgs field exist?

Answer 39

everywhere

Question 40

quarks ____interacts w/ higgs field gaining relatively large mass.

Answer 40

strongly

Question 41

electrons ___interact w/ higgs field and are extremely light

Answer 41

slightly

Question 42

photons___interact w/ higgs field and have no mass.

Answer 42

do not

Question 43

what does higgs field exert when a particle moves through it?

Answer 43

resistance

Question 44

where does inertial mass originate?

Answer 44

particles resist against acceleration from higgs field...entity that resists acceleration is the inertial mass of the particle.

Question 45

What would happen to particles if higgs field did not exist?

Answer 45

all particles would be massless

Question 46

what is lowest energy level called?

Answer 46

vaccum

Question 47

what is spontaneous symmetry breaking?

Answer 47

process of the Higgs field assuming a non-zero value throughout space

Question 48

what was the early universe?

Answer 48

first seconds of the universe where everything was radiation or energy

Question 49

When energy is converted into matter, what else is formed ?

Answer 49

antimatter

Question 50

For a proton-antiproton pair to form, the temperature must be what?

Answer 50

more than 1013 K

Question 51

what do matter and antimatter release when they annihilate on contact?

Answer 51

energy

Question 52

There must have been an asymmetry in the amount of matter and antimatter formed in order for there to be what?

Answer 52

to be predominance of ordinary matter today.

Question 53

radiation creates what 2 things?

Answer 53

particles and antiparticles

Question 54

when antiparticles and particles anihlate, what do they create?

Answer 54

radiation

Question 55

what is charge-parity violation?

Answer 55

Charge (C) and Parity (P) are two fundamental properties of particles.

Question 56

What is the charge in charge parity violation?

Answer 56

Charge is the same as the electric charge

Question 57

what does the parity in charge parity violation indicate?

Answer 57

Parity indicates the symmetry of spatial coordinates.

Question 58

If charge parity violation is NOT conserved, then what?

Answer 58

a particle and anti-particle have different properties