Talk:2853: Redshift - Revision history

172.70.90.145: Proper "unsigned ip"

2024-07-22T10:59:34Z

Proper "unsigned ip"

172.69.34.130: date

2024-07-22T10:11:47Z

date

172.70.210.234: paren

2024-07-22T10:10:02Z

paren

172.70.210.234: reply

2024-07-22T10:09:06Z

172.69.150.141: Further simplification

2023-11-17T13:43:52Z

Further simplification

Liv2splain: /* Calculation */ colors by furthest observation

2023-11-15T00:25:47Z

‎Calculation: colors by furthest observation

Liv2splain: /* Calculation */ explanatory x axis labels

2023-11-14T22:12:08Z

‎Calculation: explanatory x axis labels

Liv2splain: /* Calculation */ rm sp

2023-11-14T21:43:07Z

‎Calculation: rm sp

Liv2splain: /* Calculation */ update URLs

2023-11-14T21:41:56Z

‎Calculation: update URLs

Liv2splain: /* Calculation */ annotate Big Bang at 13.78 Gyr ago

2023-11-14T21:37:49Z

‎Calculation: annotate Big Bang at 13.78 Gyr ago

@@ Line 150: / Line 150: @@
 [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 19:25, 14 November 2023 (UTC)
-A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. [unsigned, 17 November 2023‎]
+A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. {{unsigned ip|172.69.150.141|13:43, 17 November 2023}}
 :-OL / (Om * (z + 1)**3) is not z**2. [[Special:Contributions/172.70.210.234|172.70.210.234]] 10:09, 22 July 2024 (UTC)

@@ Line 150: / Line 150: @@
 [[User:Liv2splain|Liv2splain]] ([[User talk:Liv2splain|talk]]) 19:25, 14 November 2023 (UTC)
-A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. [unsigned]
+A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. [unsigned, 17 November 2023‎]
 :-OL / (Om * (z + 1)**3) is not z**2. [[Special:Contributions/172.70.210.234|172.70.210.234]] 10:09, 22 July 2024 (UTC)

← Older revision		Revision as of 10:10, 22 July 2024
Line 151:		Line 151:

	A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. [unsigned]		A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. [unsigned]
−	:~~I don't think~~ -OL / (Om * (z + 1)3 is z2. [[Special:Contributions/172.70.210.234\|172.70.210.234]] 10:09, 22 July 2024 (UTC)	+	:-OL / (Om * (z + 1)3) is not z2. [[Special:Contributions/172.70.210.234\|172.70.210.234]] 10:09, 22 July 2024 (UTC)

← Older revision		Revision as of 10:09, 22 July 2024
Line 150:		Line 150:
	[[User:Liv2splain\|Liv2splain]] ([[User talk:Liv2splain\|talk]]) 19:25, 14 November 2023 (UTC)		[[User:Liv2splain\|Liv2splain]] ([[User talk:Liv2splain\|talk]]) 19:25, 14 November 2023 (UTC)

−	A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z	+	A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z. [unsigned]
		+	:I don't think -OL / (Om * (z + 1)3 is z2. [[Special:Contributions/172.70.210.234\|172.70.210.234]] 10:09, 22 July 2024 (UTC)

← Older revision		Revision as of 13:43, 17 November 2023
Line 149:		Line 149:
	</blockquote>		</blockquote>
	[[User:Liv2splain\|Liv2splain]] ([[User talk:Liv2splain\|talk]]) 19:25, 14 November 2023 (UTC)		[[User:Liv2splain\|Liv2splain]] ([[User talk:Liv2splain\|talk]]) 19:25, 14 November 2023 (UTC)
		+
		+	A further simplification: hyp2f1(0.5, 0.5, 1.5, z**2) = arcsin(z) / z

@@ Line 62: / Line 62: @@
 </nowiki></pre></tt>
-And should you wish to make [https://i.ibb.co/kK21n1J/time-by-redshift.png this quick reference chart for interpreting observations in the JWST era:]
+And should you wish to make [https://i.ibb.co/LpdYXNx/time-by-redshift.png this quick reference chart for interpreting observations in the JWST era:]
 {{cot|Supplemental code for Look-back Time by Redshift chart}}
@@ Line 69: / Line 69: @@
 import matplotlib.ticker as ticker
-redshifts = [z * 20 / 299 for z in range(300)]  # 0 to 20 in 300 steps
+rs = [z * 20 / 299 for z in range(300)]  # redshifts 0 to 20 in 300 steps
-look_back_times = [zt(z) for z in redshifts]
+lb = [zt(z) for z in rs]  # look_back_times
 plt.title('Look-back Time by Redshift')
 plt.xlabel('z: (observed λ - expected λ) / expected λ')
@@ Line 78: / Line 84: @@
 plt.xticks(range(21))
 plt.yticks(list(range(14)) + [age0])
-plt.text(-0.5, 13.78, "Big Bang", ha='left', va='center')
+plt.text(-0.5, 13.78, "Big Bang", va='center')
 plt.gca().yaxis.set_major_formatter(ticker.FormatStrFormatter('%.1f'))
 plt.grid(True, color='lightgray')
@@ Line 85: / Line 91: @@
 for t in range(0, 13):
-     z = redshifts[min(range(len(look_back_times)),
+     z = rs[min(range(len(lb)), key=lambda i: abs(lb[i]-t))]
      plt.text(z, t, f"   z = {z:.2f}", ha='left', va='center', fontsize='small')
@@ Line 98: / Line 103: @@
 plt.savefig('time_by_redshift.png', bbox_inches='tight')
-#plt.show()  # https://i.ibb.co/kK21n1J/time-by-redshift.png
+#plt.show()  # https://i.ibb.co/LpdYXNx/time-by-redshift.png
 </nowiki></pre></tt>
 {{cob}}
-Or [https://i.ibb.co/34Rk2WM/age-by-redshift.png this one showing the age of the universe from redshift:]
+Or [https://i.ibb.co/C537rxJ/age-by-redshift.png this one showing the age of the universe from redshift:]
 {{cot|Supplemental code for Age of Universe by Redshift chart}}
 <tt><pre><nowiki>
-plt.clf()  # reset plot
+plt.clf()  # Reset plot
-redshifts = [z * 15 / 299 + 5 for z in range(300)]  # 5 to 20 in 300 steps
+plt.plot([x for x in rs if x<fo], [y for x,y in zip(rs,ages) if x<fo], color='red')
-ages = [age_at_z(z) * 1000 for z in redshifts]  # Gyr to million years
+plt.plot([x for x in rs if x>fo], [y for x,y in zip(rs,ages) if x>fo], color='darkred')
 plt.title('Age of Universe by Redshift')
 plt.xlabel('z: (observed λ - expected λ) / expected λ')
@@ Line 122: / Line 131: @@
 plt.savefig('age_by_redshift.png', bbox_inches='tight')
-#plt.show()  # https://i.ibb.co/34Rk2WM/age-by-redshift.png
+#plt.show()  # https://i.ibb.co/C537rxJ/age-by-redshift.png
 </nowiki></pre></tt>
 {{cob}}