From eb58586a8df3becd267dde8757d289d38201b0d0 Mon Sep 17 00:00:00 2001
From: Karchnu <karchnu@karchnu.fr>
Date: Tue, 5 Oct 2021 20:18:08 +0200
Subject: [PATCH] Chapter 3: WIP.

---
 universe-from-nothing.ms                      |  1 +
 .../ch3_light-from-the-beginning-of-time.ms   | 28 +++++++++++++++++++
 universe-from-nothing/header.ms               |  3 +-
 3 files changed, 31 insertions(+), 1 deletion(-)
 create mode 100644 universe-from-nothing/ch3_light-from-the-beginning-of-time.ms

diff --git a/universe-from-nothing.ms b/universe-from-nothing.ms
index cff8ee2..c7e1566 100644
--- a/universe-from-nothing.ms
+++ b/universe-from-nothing.ms
@@ -4,4 +4,5 @@
 .so universe-from-nothing/preface.ms
 .so universe-from-nothing/ch1_a-cosmic-mystery-story_beginnings.ms
 .so universe-from-nothing/ch2_a-cosmic-mystery-story_weighing-the-universe.ms
+.so universe-from-nothing/ch3_light-from-the-beginning-of-time.ms
 .so universe-from-nothing/annex-events.ms
diff --git a/universe-from-nothing/ch3_light-from-the-beginning-of-time.ms b/universe-from-nothing/ch3_light-from-the-beginning-of-time.ms
new file mode 100644
index 0000000..ab3f634
--- /dev/null
+++ b/universe-from-nothing/ch3_light-from-the-beginning-of-time.ms
@@ -0,0 +1,28 @@
+.NH 1
+Light from the beginning of time
+.PP
+.METAINFO1
+This chapter introduces a more reliable way to determine the geometry of the universe, thanks to the cosmic microwave background radiations.
+.METAINFO2
+Trying to measure the universe weight by gravitational lensing galaxies and clusters is fundamentally flawed.
+This could only provide a rough approximation in case the weight actually came from somewhere within clusters.
+In case the weight of the universe comes from between clusters, then our method doesn't work.
+
+Another involves observing cosmic microwave background radiations (CRBR) and actually measure see the curvature of the universe.
+
+.SH
+Measuring the geometry of the universe
+.PP
+Before trying to explain how to measure the curvature of the universe, let's try to answer a simpler question.
+
+.QUESTION "How to measure the curvature of a world in two dimensions?"
+.TBD
+.SH
+Cosmic Microwave Background Radiations
+.PP
+Somewhere around 300 000 years after the Big Bang, the universe became cold enough to emit radiations.
+.TBD
+
+.EXPLANATION1
+Gravity is propagated at the speed of light.
+.EXPLANATION2
diff --git a/universe-from-nothing/header.ms b/universe-from-nothing/header.ms
index b7da3a6..fa7b8be 100644
--- a/universe-from-nothing/header.ms
+++ b/universe-from-nothing/header.ms
@@ -39,6 +39,7 @@ Lastly compiled the
 (day/month/year, you know, like in any sane civilization).
 .br
 .UL Status :
-preface, chapter 1 & 2 are almost done (maybe require some extra info and polishing, but not much).
+preface, chapters 1 & 2 are almost done (maybe require some extra info and polishing, but not much).
+Chapter 3: WIP.
 Annexes are WIP.
 .AE