nearly fully fleshed out now

introduction.typ

@@ -9,7 +9,10 @@
 
 - Is strongly linked to the formation and growth of the first galaxies and black holes.
 
-- Sets the stage for many observables: CMB secondary anisotropies, 21-cm signal, high-z galaxy surveys.
+- Sets the stage for many observables:
+  - CMB secondary anisotropies
+  - 21-cm signal
+  - high-z galaxy surveys.
 // reformulate
 
 
@@ -20,12 +23,19 @@ The brigthtness temperature describes the difference between the CMB temperature
 
 #v(1em)
 
-#grid(columns: 2, align: center)[
-  #image("assets/cmb_black_body_spectrum.svg", height: 1fr, fit: "contain")   #text(size: 0.8em)[from @cmb_spectrum]
+#grid(columns: 2, align: center, column-gutter: 1em)[
+  #image("assets/cmb_and_dtb.jpeg", height: 1fr, fit: "contain")   #text(size: 0.8em)[from @cmb_spectrum]
 ][
   #pause
-  Removing the contribution from the black body spectrum of the CMB yields the explicit 21-cm signal:
-  #image("assets/cmb_black_body_spectrum.svg", height: 1fr, fit: "contain")
+  #set text(size: 0.8em)
+  remove contribution from the BB spectrum:
+
+  _differential brightness temperature_
+
+  $==>$ the actual 21-cm signal
+
+  #image("assets/brighness_temperature.png", fit: "contain")
+  from @Schaeffer_2023
 ]
 
 #pagebreak()
@@ -37,6 +47,9 @@ The brigthtness temperature describes the difference between the CMB temperature
   #text(size: 0.8em)[from @Pritchard2012]
 ]
 
+// COMMENTS:
+
+
 
 == Expression the 21-cm signal
 Expressing the _differential brightness temperature_ (e.g @Pritchard2012):
@@ -59,113 +72,37 @@ $ <eq:dTb>
 #layouts.contained(
   [
     *Traditional approaches*
-
-    // keypoints that describe heavy hydro + radiative transfer simulations
-    - require hydrodynamics
-    - require radiative transfer
-    - scale poorly
+    // From first principles
+    - need to cover large dynamic range
+    // small scales to resolve sources + sinks + feedback
+    // large scales to capture statistics
+    - hydrodynamics & radiative transfer
+    - hard to scale
 
     $=>$ no reproducibility
     #pause
   ],
   [
-    #text(weight: "bold")[semi-numerical approaches]
+    #pad(1em)[
+      #align(left)[
+        #text(weight: "bold")[semi-numerical approaches]
 
-    such as #beorn @Schaeffer_2023, `21cmFAST` [CITATION]
-    - approximative treatment
-    - link
-    - scalable + efficient
+        such as #beorn @Schaeffer_2023, `21cmFAST` @21cmfast
 
-    $=>$ reproducible and flexible
+        // IF ASKED: difference with `21cmFAST`:
+        // based on excursion formalistm -> only valid >= 1Mpc, which is ideal for large volumes + statistics => 21-cm forecasts
+
+        $->$ approximative treatment
+
+        $->$ link
+
+        $->$ scalable + efficient
+
+        $=>$ reproducible and flexible
+        // interesting to build emulators for instance
+      ]
+
+    ]
   ]
 )
 
-
-// #layouts.two-boxes(
-//   [
-//     #text(weight: "bold")[Traditional approaches]
-
-//     // keypoints that describe heavy hydro + radiative transfer simulations
-//     - require hydrodynamics
-//     - require radiative transfer
-//     - scale poorly
-
-//     $=>$ no reproducibility
-//     #pause
-//   ],
-//   [
-//     *semi-numerical approaches*
-
-//     such as #beorn @Schaeffer_2023, `21cmFAST` [CITATION]
-//     - approximative treatment
-//     - link
-//     - scalable + efficient
-
-//     $=>$ reproducible and flexible
-
-
-//   ]
-// )
-
-#pagebreak()
-
-== Matrix
-
-#layouts.matrix((
-  brand.wordmark,
-  brand.wordmark,
-  brand.wordmark,
-  brand.wordmark,
-  brand.wordmark,
-  brand.wordmark
-))
-
-== Contained
-#layouts.contained(
-  columns(2, [
-    - #lorem(10)
-    - #lorem(15)
-    - #lorem(25)
-  ]),
-  brand.wordmark
-)
-
-
-
-== Four columns
-
-#layouts.four-columns(
-  [
-    #text(weight: "bold", brand.wordmark)
-    #v(1em)
-    #text(size: 10.5pt)[#lorem(60)]
-  ],
-  [
-    #text(weight: "bold", brand.wordmark)
-    #v(1em)
-    #text(size: 10.5pt)[#lorem(45)]
-  ],
-  [
-    #text(weight: "bold", brand.wordmark)
-    #v(1em)
-    #text(size: 10.5pt)[#lorem(75)]
-  ],
-  [
-    #text(weight: "bold", brand.wordmark)
-    #v(1em)
-    #text(size: 10.5pt)[#lorem(50)]
-  ]
-)
-
-
-
-== Two columns
-
-#layouts.contained(
-  columns(2, [
-    - #lorem(10)
-    - #lorem(15)
-    - #lorem(25)
-  ]),
-  brand.wordmark
-)