diff --git a/journal/2021-08-15.md b/journal/2021-08-15.md
index 832006e74..9b2bc5d4e 100644
--- a/journal/2021-08-15.md
+++ b/journal/2021-08-15.md
@@ -7,4 +7,6 @@
   - [[radio caso]]
 - [[coop pixar]]
 - [[david deutsch]]
-  - [[the fabric of reality]]
\ No newline at end of file
+  - [[the fabric of reality]]
+- [[max tegmark]]
+  - [[our mathematical universe]]
\ No newline at end of file
diff --git a/our mathematical universe.md b/our mathematical universe.md
new file mode 100644
index 000000000..83f3c5a83
--- /dev/null
+++ b/our mathematical universe.md	
@@ -0,0 +1,4 @@
+# our mathematical universe
+
+- https://twitter.com/flancian/status/1426915098950504452
+
diff --git a/the fabric of reality.md b/the fabric of reality.md
index e60d90114..f545be6b5 100644
--- a/the fabric of reality.md	
+++ b/the fabric of reality.md	
@@ -2,7 +2,7 @@
 
 - a [[book]]
   - by [[david deutsch]]
-  - [[wp]] https://en.wikipedia.org/The_Fabric_of_Reality
+  - [[wp]] https://en.wikipedia.org/wiki/The_Fabric_of_Reality
     - [[go]] [[wp]]