Numerical calculations for "Origins of Cosmological Temperature"

This SageMath notebook performs numerical calculations for the paper Origins of Cosmological Temperature and the supplemental note Calculations for "Origins of Cosmological Temperature".

It makes graphs of the two anharmonic potentials and does some arithmetic.

Section headings are as in the supplemental note.

3.5 Action in dimensionless variables

In [1]:
ah = var('ah')
E_ah = 0.15
ah_lim=1.08
#ah_lim=1.2
ah_plot=plot((1/2)*(ah^2-ah^4), (ah,-ah_lim,ah_lim),aspect_ratio=12)
#ah_plot+= circle((1.07,E_ah),0.02,aspect_ratio=0.1,fill=true)
ah_plot+=text(r'$E_{\hat{a}}$', (-1.35,E_ah),fontsize=8)
#ah_plot+=text(r'$E_{\hat{a}}=\frac{1}{2}\epsilon_{\mathrm{w}}^4 E_b$',
#              (-1.6,E_ah),fontsize=8)
#ah_plot+=text(r'$E_{\hat{a}}=\frac{1}{2}\epsilon_{\mathrm{w}}^4 E_b$',
#              (1.4,E_ah),fontsize=8)
ah_plot+=text(r'$0$',(-1.3,0),fontsize=6)
ah_plot+=text(r'$\frac{1}{8}$',(-1.32,0.125),fontsize=6,aspect_ratio=1)
ah_plot+=text(r'$0$',(0,-0.006),fontsize=6,aspect_ratio=1)
#ah_plot+=text(r'$\frac{1}{\sqrt{2}}$',(1/sqrt(2),-0.015),fontsize=6,aspect_ratio=1)
#ah_plot+=text(r'$-\frac{1}{\sqrt{2}}$',(-1/sqrt(2),-0.015),fontsize=6,aspect_ratio=1)
ah_plot+=text(r'$1$',(0.95,-0.006),fontsize=6,aspect_ratio=1)
ah_plot+=text(r'$-1$',(-1.0,-0.006),fontsize=6,aspect_ratio=1)
#ah_plot+=text(r'$0$',(-4.5,0),fontsize=2,)
#ah_plot+=text(r'$V_{\hat{a}}$',(-1.5,-0.1),fontsize=14)
ah_plot+=text(r'$V_{\hat{a}}=\frac{1}{2}(\hat{a}^2-\hat{a}^4)$',(0,-0.04),fontsize=12)
#ah_plot+=text(r'$\hat{a}$',(0,-0.05),fontsize=14)
ah_plot+= plot(0.125,(ah,-1.25,1.25),linestyle=":")
ah_plot+= plot(0,(ah,-1.25,1.25),linestyle=":")
ah_plot+= plot(E_ah,(ah,-1.25,1.25),linestyle=":")
ah_plot+=arrow((1.11,-0.08),(1.13,-0.08-.02),width=.5,arrowsize=1.5)
ah_plot+=arrow((-1.13,-0.08-.02),(-1.11,-0.08),width=.5,arrowsize=1.5)
ah_plot+=arrow((0.97,1/16),(1.00,1/16-.02),width=.5,arrowsize=1.5)
ah_plot+=arrow((-1.00,1/16-.02),(-0.97,1/16),width=.5,arrowsize=1.5)
ah_plot+=arrow((-.34,1/16),(-.27,1/16-.017),width=.5,arrowsize=1.5)
ah_plot+=arrow((.27,1/16-.017),(.34,1/16),width=.5,arrowsize=1.5)
ah_plot.save('ah_plot_2.pdf',dpi=200,axes=False)
show(ah_plot,axes=False,dpi=200,figsize=[3.2,2.4])
Out[1]:
In [2]:
b = var('b')
E_b = 12
b_plot=plot((1/2)*(b^2-1)^2, (b,-2.5,2.5),aspect_ratio=.5)
#b_plot=plot((1/2)*(b^2-1)^2, (b,-3,3),aspect_ratio=.5)
#b_plot+= circle((2.7,E_b),0.25,aspect_ratio=1,fill=true)
b_plot+=text(r'$E_b$',(-3.1,E_b),fontsize=10)
b_plot+=text(r'$0$',(-3.0,0),fontsize=6)
b_plot+=text(r'$V_b=\frac{1}{2}(b^2-1)^2$',(0,E_b/2),fontsize=12)
b_plot+=text(r'$b$',(0,-1),fontsize=12)
b_plot+= plot(0,(b,-2.7,2.7),linestyle=":")
b_plot+= plot(E_b,(b,-2.7,2.7),linestyle=":")
b_plot+=text(r'$1$',(1.0,-0.4),fontsize=6)
b_plot+=text(r'$0$',(0.0,-0.4),fontsize=6)
b_plot+=text(r'$-1$',(-1.09,-0.4),fontsize=6)
#b_plot+=arrow((1.97,E_b-2),(1.9,E_b-4),width=.5,arrowsize=2)
b_plot+=arrow((-1.97,E_b-2),(-1.9,E_b-4),width=.5,arrowsize=2)
b_plot.save('b_plot.pdf',dpi=200,axes=False)
show(b_plot,axes=False,dpi=200,figsize=[3.2,2.4])
Out[2]:

5.1 Fundamental constants

In [3]:
%display latex
LE = lambda latex_string: LatexExpr(latex_string);
# pretty_print(LE("c ="),c);

declare units as variables

In [4]:
# declare units as variables
s = var('s', domain='positive'); assume(s,'real');
GeV = var('GeV', domain='positive'); assume(GeV,'real');
J = var('J', domain='positive'); assume(J,'real');
m = var('m', domain='positive'); assume(m,'real');
meters = var('meters', domain='positive'); assume(meters,'real');
kg = var('kg', domain='positive'); assume(kg,'real');
K = var('K', domain='positive'); assume(K,'real');
C = var('C', domain='positive'); assume(C,'real');

fundamental constents from NIST 2018

In [5]:
# fundamental constants (NIST 2018)
# c = 299792458 * m * s^(-1)
# hbar = 1.054571817  * 10^(-34)* J * s
# e = 1.602176634  * 10^(-19) * C 
# G = 6.67430*10^(-11)*m^3*kg^(-1)* s^(-2)
# kB = 1.380649 * 10^(-23) * J * K-1
#
#
c = 299792458 * meters * s^(-1);
e_charge = 1.602176634  * 10^(-19) * C;
hbar = 1.054571817*10^(-34)*J*s;
kB = 1.380649*10^(-23)*J*K^(-1);
#
G = 6.67430*10^(-11)*m^3*kg^(-1)* s^(-2);
kappa = N(8*pi)*G;
#
pretty_print(LE(r"c ="),c);
pretty_print(LE(r"e ="),e_charge);
pretty_print(LE(r"\hbar ="),hbar);
pretty_print(LE(r"k_{B} ="),kB);
pretty_print(LE(r"G ="),G);
pretty_print(LE(r"\kappa ="),kappa);
Out[5]:
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use c=1 units with unit of energy = GeV

In [6]:
#  use c=1 units with unit of energy = GeV
m = c^(-1)*meters;
J = e_charge^(-1) * C * 10^(-9) * GeV
kg = J*s^2*m^(-2)
hbar = 1.054571817*10^(-34)*J*s;
kB = 1.380649*10^(-23)*J*K^(-1);
#
G = 6.67430*10^(-11)*m^3*kg^(-1)* s^(-2);
kappa = N(8*pi)*G;
pretty_print(LE(r"\hbar ="),hbar);
pretty_print(LE(r"k_{B} ="),kB);
pretty_print(LE(r"G ="),G);
pretty_print(LE(r"\kappa ="),kappa);
Out[6]:
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5.2 Standard Model coupling constants from PDG

In [7]:
# Particle Data Group (2018,2019)
#
# GFermi =  1.1663787*10^(-5) *GeV^(-2);
# mW = 80.379*GeV;
# mH = 125.35*GeV;
# 
GFermi =  1.1663787*10^(-5)*GeV^(-2);
mW = 80.379*GeV;
mH = 125.10*GeV;
#
pretty_print(LE(r"G_F ="),GFermi);
pretty_print(LE(r"m_W ="),mW);
pretty_print(LE(r"m_H ="),mH);
Out[7]:
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In [8]:
hbar_v = N(2^(-1/4))*GFermi^(-1/2)
pretty_print(LE(r"\hbar v  = 2^{-1/4} G_F^{-1/2}="),hbar_v)
v = hbar_v/hbar
pretty_print(LE(r"v ^{-1} ="),1/v);
g = 2*mW/hbar_v;
pretty_print(LE(r"g = \frac{2 m_W}{\hbar v }="),g)
#pretty_print(LE(r"g^2 = \left(\frac{2 m_W}{v }\right)^2="),g^2);
lambdaH = mH/hbar_v;
pretty_print(LE(r"\lambda = \frac{m_H}{\hbar v }="),lambdaH)
Out[8]:
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5.3 Gravitational and weak time scales $t_{\mathrm{grav}}$, $t_{\mathrm{W}}$

In [9]:
tgrav = sqrt(kappa*hbar);
pretty_print(LE(r"t_{\mathrm{grav}} = (\hbar\kappa)^{1/2}=\
(8\pi)^{1/2} t_{P}="),N((8*pi)^(1/2)),LE(r"t_{P}\\="),tgrav)
Out[9]:
In [10]:
tW = hbar/mW;
pretty_print(LE(r"t_{\mathrm{W}}=\frac{\hbar}{m_W}="),tW)
Out[10]:

5.4 The scalar field energy density $\mathcal{E}_{0}$

In [11]:
E0 = hbar*lambdaH^2*v^4/8;
ratio1 = tW^4*E0/hbar;
pretty_print(LE(r"\frac{1}{\hbar}\mathcal{E}_{0}="),\
             ratio1,LE(r"\: t_{\mathrm{W}}^{-4}"))
Out[11]:

5.5 Seesaw time scale $t_{I}$

In [12]:
tI = (3/(kappa*E0))^(1/2);
ratio2 = tI*tgrav/tW^2;
pretty_print(LE(r"t_{I}="),
             ratio2,LE(r"\:\frac{t_{\mathrm{W}}^{2}}{t_{\mathrm{grav}}}"),\
            LE(r"="),tI)
Out[12]:
In [13]:
ratio12 = N(sqrt(3/2))*g^2/lambdaH;
pretty_print(LE(r"\sqrt{\frac32}\frac{g^2}{\lambda}="),ratio12);
Out[13]:
In [14]:
tI*c;
pretty_print(LE(r"t_{I} c="),tI*c);
Out[14]:

5.6 Seesaw ratio $\epsilon_W$

In [15]:
epsilonW = (kappa*hbar/(2*g^2*tI^2))^(1/4);
pretty_print(LE(r"\epsilon_{W}="),epsilonW)
Out[15]:
In [16]:
ratio3 = epsilonW*tW/tgrav;
ratio4 = epsilonW*tI/tW;
ratio34 = sqrt(ratio3*ratio4);
pretty_print(LE(r"\epsilon_{W}="),ratio34,
             LE(r"\:\left(\frac{t_{\mathrm{grav}}}{t_{I}}\right)^{1/2}"))
pretty_print(LE(r"\epsilon_{W}="),ratio3,
             LE(r"\:\frac{t_{\mathrm{grav}}}{t_{\mathrm{W}}}"))
pretty_print(LE(r"\epsilon_{W}="),ratio4,
             LE(r"\:\frac{t_{\mathrm{W}}}{t_{I}}"))
Out[16]:
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In [17]:
ratio134=(2*g^2)^(-1/4);
pretty_print(LE(r"\left(\frac{1}{2g^2}\right)^{1/4}="),ratio134)
Out[17]:
In [18]:
ratio13=(lambdaH^2/(3*g^6))^(1/4);
pretty_print(LE(r"\left(\frac{\lambda^2}{3g^6}\right)^{1/4}="),ratio13)
Out[18]:
In [19]:
ratio14=((3*g^2)/(4*lambdaH^2))^(1/4);
pretty_print(LE(r"\left(\frac{3g^2}{4\lambda^2}\right)^{1/4}="),ratio14)
Out[19]:

5.7 Units of action for the two oscillators

In [20]:
ratio5=6*N(pi)^2/g^2;
pretty_print(LE(r"\frac{6\pi^{2}}{g^2}="),ratio5)
Out[20]:

7.5 $K(1/\sqrt{2})$

In [21]:
K = N(gamma(1/4)^2/(4*pi^(1/2)));
pretty_print(LE(r"K(1/\sqrt{2}) = \frac{\Gamma(1/4)^{2}}{4 \pi^1/2}="),K)
Out[21]:

7.6 $\langle \mathrm{cn}^2 \rangle$ for $k=1/\sqrt2$

In [22]:
cn2ave = N(pi/2)/K^2;
pretty_print(LE(r"\langle \mathrm{cn}^2 \rangle=\frac{2}{\pi^{2}}\frac{1}{K^{2}}="),cn2ave)
Out[22]:

8. Cosmological temperature

In [23]:
kT = mH/N((6*pi)^(1/2));
pretty_print(LE(r"k_B T ="),kT)
Out[23]:
In [24]:
pretty_print(LE(r"T ="),kT/kB) 
Out[24]:

9.1 Solution for $\hat a$ in co-moving time

In [25]:
pretty_print(LE(r"\frac{\epsilon_W}{\sqrt{2}} ="),epsilonW/N(sqrt(2))) 
Out[25]:

9.2 $\hat a_{\mathrm{EW}}$

In [26]:
ratio6 =N(3^(1/2)*pi/(8*K^2))*(2*mW/mH);
pretty_print(LE(r"\hat a^2_{\mathrm{EW}} ="),\
             LE(r"\frac{3^{1/2}\pi}{8 K^2}\frac{2m_W}{m_H}(2 E_{\hat a})^{1/2}="),\
             ratio6,\
            LE(r"\:(2 E_{\hat a})^{1/2}"))
Out[26]:
In [27]:
pretty_print(LE(r"\hat a_{\mathrm{EW}} ="),\
             sqrt(ratio6),\
            LE(r"\:(2 E_{\hat a})^{1/4}"))
Out[27]:
In [28]:
thatEW = asinh(ratio6)/2;
pretty_print(LE(r"\hat t_{\mathrm{EW}} ="),thatEW)
Out[28]:
In [29]:
tEW = thatEW * tI;
pretty_print(LE(r"t_{\mathrm{EW}} ="),tEW)
Out[29]:
In [30]:
TEW = inverse_jacobi('cn', e^(-thatEW), 0.5);
pretty_print(LE(r"T_{\mathrm{EW}} ="),TEW,LE(r"\;\epsilon_a"))
Out[30]: