# Mathematics
π = pi = 3.14159265359
ℯ = e = 2.71828182846
ϕ = phi = golden_ratio = 1.61803398875
𝑖 = i = imaginary_unit = complex(0, 1)
γ = euler_mascheroni = 0.5772156649
ζ_3 = apery = 1.2020569032
G = catalan = 0.9159655942
sqrt2 = 1.41421356237
sqrt3 = 1.73205080757
ln2 = log2 = 0.69314718056
ln10 = log10 = 2.30258509299
khinchin = 2.68545200107
twin_prime = 0.6601618158468696
conways_constant = 1.303577269
feigenbaum_constant = 4.669201609
glaisher_constant = 1.282427129
lehmer_constant = 0.110264815
levy_constant = 3.275822918
mills_constant = 1.306377883
mrB_constant = 0.2614972128
odds_constant = 0.78515625
omega_constant = 0.5671432904
sierpinski_constant = 2.584981759
thue_morse_constant = 0.4124540336
universal_parabolic_constant = 2.29558714939
viswanath_constant = 1.13198824
mandelbrot_approximate_area = 2.089

# Physics and Astronomy
𝑐 = c = speed_of_light = 299792458
𝐺 = G = gravitational_constant = 6.67430e-11
ℎ = h = plancks_constant = 6.62607015e-34
ℏ = h_bar = reduced_plancks_constant = 1.054571817e-34
𝑘 = k = boltzmanns_constant = 1.380649e-23
𝑁_A = N_A = avogadros_number = 6.02214076e23
𝑅 = R = gas_constant = 8.314462618
σ = stefan_boltzmann = 5.670374419e-8
ε_0 = vacuum_permittivity = 8.8541878128e-12
μ_0 = vacuum_permeability = 4 * pi * 1e-7
k_e = coulomb_constant = 1/(4*pi*vacuum_permittivity)
α = fine_structure = 1 / 137
m_p = proton_mass = 1.67262192369e-27
m_n = neutron_mass = 1.67492749804e-27
m_e = electron_mass = 9.1093837015e-31
a_0 = bohr_radius = 5.29177210903e-11
R_inf = rydberg_constant = 10973731.568160
m_u = atomic_mass_constant = 1.66053906660e-27
F = faraday_constant = 96485.33212
b = wien_displacement = 2.897771955e-3
H_0 = hubble_constant = 70  # Value between 67 and 73
Λ = cosmological_constant = 1.1056e-52
Gpc = giga_parsec = 3.08567758128e25
solar_mass = 1.98847e30
solar_radius = 6.9634e8
solar_luminosity = 3.828e26
AU = astronomical_unit = 149597870.7
ly = light_year = 9.46073047258e15
pc = parsec = 3.08567758128e16
c_air = sound_speed_air = 343.2
c_water = sound_speed_water = 1481
c_steel = sound_speed_steel = 5130
l_P = planck_length = 1.616255e-35
t_P = planck_time = 5.391247e-44
T_P = planck_temperature = 1.416784e32

# Mechanics
eV = electron_volt = 1.602176634e-19
joule_per_electronvolt = 6.242e+12
N = newton = 1
Pa = pascal = 1
atm = atmosphere = 101325
bar = 100000
torr = 133.322
dyne = 1e-5
erg = 1e-7
cal = calorie = 4.184
btu = 1055.06
hp = horsepower = 745.7
W = watt = 1

# Quantum Mechanics
alpha = fine_structure_constant = 7.2973525664e-3
h_over_4pi = quantum_of_circulation = 3.6369475516e-4
h_over_2pi = quantum_of_circulation_times_2 = 7.2738951033e-4
Phi_0 = flux_quantum = 2.067833848e-15
K_J = josephson_constant = 483597.8484e9
R_K = von_klitzing_constant = 25812.80745
mu_B = bohr_magneton = 9.2740100783e-24
mu_N = nuclear_magneton = 5.0507837461e-27
lambda_C = compton_wavelength = 2.42631023867e-12
lambda_C_over_2pi = compton_wavelength_over_2pi = 386.1592678e-15
r_e = classical_electron_radius = 2.8179403262e-15
E_h = hartree_energy = 4.3597447222071e-18
G_0 = conductance_quantum = 7.748091729e-5
R_0_inv = inverse_conductance_quantum = 12906.40372
mu_0 = magnetic_constant = 1.25663706212e-6
epsilon_0 = electric_constant = 8.8541878128e-12
Z_0 = characteristic_impedance_of_vacuum = 376.730313461
e_c = elementary_charge = 1.602176634e-19

# Chemistry
V_m = molar_volume_ideal_gas = 22.414
𝑅 = R = molar_gas_constant = 8.314462618
M_air = molar_mass_of_air = 28.97e-3
ρ_water = density_of_water = 1e3
R_d = gas_constant_dry_air = 287.05
eV = electronvolt = 1.602176634e-19
K_w = ion_product_of_water = 1.0e-14  # at 25°C
pK_w = 14  
K_b_chem = boltzmann_constant_chem = 1.380649e-23  
h_chem = planck_constant_chem = 6.62607015e-34  

# Geophysics and Geology
𝑔 = g = earth_gravity = 9.80665
M_E = earth_mass = 5.97237e24
R_E = earth_equatorial_radius = 6378.1
R_p = earth_polar_radius = 6356.8
R_m = earth_mean_radius = 6371.0
f = earth_oblateness = 0.0033528
P_sidereal = sidereal_year = 365.25636
P_tropical = tropical_year = 365.24219

# Electronics and Computer Science
bit = 1
byte = 8 * bit
kB = kilobyte = 1024 * byte
MB = megabyte = 1024 * kilobyte
GB = gigabyte = 1024 * megabyte
TB = terabyte = 1024 * gigabyte
PB = petabyte = 1024 * terabyte
EB = exabyte = 1024 * petabyte
ZB = zettabyte = 1024 * exabyte
YB = yottabyte = 1024 * zettabyte
fLOPS = floating_point_operations_per_second = 1  
MIPS = million_instructions_per_second = 1e6  
Baud = symbols_per_second = 1  
bps = bits_per_second = 1  
Hz = hertz = cycles_per_second = 1  
