[Edu-sig] more in the "Rich Data Structure" series
kirby urner
kirby.urner at gmail.com
Mon Dec 3 04:22:27 CET 2012
"""
Quantum Field Theory:
Skeletal draft of objects
Rich Data Series
To help with studies, students learning Python might bend its
notation to help them wrap their heads around this and that.
Here's a module I've been working on after listening to
Sean Carroll's ISEPP lecture in Portland last night (isepp.org).
Write-up:
http://worldgame.blogspot.com/2012/11/isepp-physics-lecture.html
I haven't double checked everything as the primary idea is
to get across the idea. People will role their own. These are
more in the way of doodles at this point, minus much of
anything to hold it together. Slapping it out there as open
source.
If you fix a broken bit, fork a new version,
take it as inspiration to start from scratch, feel free to
add your name to the list of contributors. Many of you have
already. My thanks to the Wikipedia articles and other
authors I read and/or listened to or otherwise appreciated.
Other Rich Data Structure stuff
http://mail.python.org/pipermail/edu-sig/2005-November/005533.html
http://www.mail-archive.com/edu-sig@python.org/msg02457.html
http://mybizmo.blogspot.com/2008/01/rich-data-structures.html
K. Urner
edu-sig
"""
ANTI = True
class Fermion():
"""fractional spin, Fermi-Dirac statistics"""
spin = 1/2 # J
class Boson():
"""whole number spin, Bose-Einstein statistics"""
spin = 0 # may override in subclass to 1 or 2 (Higgs)
class Field:
pass
class Strong(Field):
"""
quantum chromodynamics
"""
def __init__(self, anti=False):
self.anti = anti
if anti:
self.color = "anti-" + self.color # reverse color if anti-particle
class ElectroWeak(Field):
"""
quantum electrodynamics
"""
def __init__(self, anti=False):
self.anti = anti
if anti:
self.charge = -self.charge # reverse charge if anti-particle
# Quarks: 6 with oppositely charged pairs = 12, each with 3 colors =
36 permutations
class Quark(Fermion, Strong, ElectroWeak):
"""
Meson = Quark + Quark
Baryon = Quark + Quark + Quark (e.g. proton, neutron)
"""
def __init__(self, color, anti=False):
color = color.lower()
if color not in ["blue", "red", "green"]:
raise ValueError
Strong.__init__(self, anti)
ElectroWeak.__init__(self, anti) # reverse charge if anti
class Up(Quark):
mass = 2.4 # m Mev/c2
charge = 2/3 # Q
class Down(Quark):
mass = 4.4
charge = -1/3
class Charm(Quark):
mass = 1320
charge = 2/3
class Strange(Quark):
mass = 87
charge = -1/3
class Top(Quark):
mass = 172700
charge = 2/3
class Bottom(Quark):
mass = 4240
charge = -1/3
# Gauge Bosons
class W(Boson, ElectroWeak):
mass = 80387
charge = 1
spin = 1
class Z(Boson, ElectroWeak):
mass = 91187.6
charge = 0
spin = 1
class Photon(Boson, ElectroWeak):
mass = 0
charge = 0
class Gluon(Boson, Strong):
spin = 1 # overrides attribute of Boson
mass = 0
charge = 0
def __init__(self, color, anticolor):
self.color = coler
self.anticolor = anticolor
# Higgs Boson
class Higgs(Boson):
spin = 2 # overrides attribute of Boson
mass = 125000
charge = 0
# Leptons (6 + 6 anti = 12)
class Electron(Fermion, ElectroWeak):
mass = 0.511
charge = -1
class Tau(Fermion, ElectroWeak):
mass = 1776.82
charge = -1
class Muon(Fermion, ElectroWeak):
mass = 105.7
charge = -1
# masses are superpositional
class Neutrino_E(Electron):
mass = .0022
charge = 0
class Neutrino_T(Tau):
mass = 0.17
charge = 0
class Neutrino_M(Muon):
mass = 15.5
charge = 0
# Hadrons (composed of 2 or 3 quarks, or "exotic" if more (not confirmed)
class Baryon(Fermion, Strong, ElectroWeak):
pass
class Nucleon(Baryon):
"""Baryon -- one of two kinds of Hadron"""
class Proton(Nucleon):
"""
Up("blue") + Up("red") + Down("green")
Proton() + Electron() -> Neutron() + Neutrino_E()
"""
mass = 938.27
charge = 1
class Neutron(Nucleon):
"""
Down("green") + Down("red") + Up("blue")
Neutron() -> Proton() + Electron() + Neutrino_E(ANTI)
"""
mass = 939.57
charge = 0
class Sigma(Baryon):
"""
Have two Ups or two Downs, and one something else (charm, strange,
bottom, top -- tops are too fast)
"""
pass
class Omega(Baryon):
"""
Have no Up or Down quarks
"""
class Lambda(Baryon):
"""
One Up, One Down, and one something else
"""
class Xi(Baryon):
"""
One up or down + two heavier quarks
"""
class Delta(Baryon):
"""
up and down quarks only, spin 3/2 vs. nucleon 1/2
Decay into nucleon + pion in short order
"""
mass = 1232
class Meson(Boson, Strong, ElectroWeak):
""" Meson -- the other kind of Hadron besides Baryon
Unstable. Charged -> electrons + neutrinos, Uncharged -> photons
Flavorless (quarkonium): quark + anti-quark of same type
Flavorful: quark + anti-quark of different type
"""
class D(Meson):
"""Flavorful with charm"""
class B(Meson):
"""Flavorful with charm"""
class Upsilon(Meson):
"""Flavorless with bottom (bottomonium, a form of quarkonium)"""
mass = 9460
spin = 1
class JPsi(Meson):
"""Flavorless with charm (excited charmonium)"""
pass
class Pion(Meson):
"""
Up() + Down(ANTI) charge = 1 --> 99.9877% Muon(ANTI) +
Neutrino_M(), .0123% Electron(ANTI) + Neutrino_E
Up() + Up(ANTI) or Down() + Down(ANTI) charge = 0
Down() + Up(ANTI) charge = -1 --> 99.9877% Muon() +
Neutrino_M(ANTI), .0123% Electron() + Neutrino_E(ANTI)
"""
mass = 139.57 # if charged, else 135
parity = -1
class Rho(Meson):
mass = 770
class Phi(Meson):
"""
Flavorless with strange
"""
mass = 1019.4
charge = 0 # 3 states
class Kaon(Meson): # K Mesons
"""
Four types
Flavorful: Strange() + Up() or Down()
"""
charge = 1
mass = 493.7 if charge == (1 or -1) else 497.6
class Eta(Meson):
charge = 0
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