diff --git a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/topic.en.md b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/topic.en.md
index 4b49a5bbf..3459933bd 100644
--- a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/topic.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/topic.en.md
@@ -1,4 +1,6 @@
 ---
 title: 'Physical systems versus optical systems '
+published: false
+visible: false
 ---