Final answer:
In the context of physics and spacetime diagrams, events occurring on the left side precede events on the right side, which is indicated by the provided example showing time flowing from left to right from the Big Bang to the Present.
The correct answer is options 1) Right side.
Step-by-step explanation:
The question 'Events on the left side occur just before those on which side?' is somewhat ambiguous without a specific context, as it could be related to various subjects such as reading direction, time-space diagrams in physics, or stage directions. However, given the provided references, it appears the context is related to physics and the concept of events in a spacetime context, possibly related to simultaneity and the direction of time.
In the context of physics and spacetime diagrams, where time is typically represented vertically and space horizontally, if an event occurs on the left side, it would conventionally be followed by events to the right side. This is particularly illustrated by the example referencing a new chapter in a book starting on the right-side page and the diagram showing the Big Bang on the left and the Present on the right with an arrow indicating the direction of time.
However, it's worth noting that in different contexts, 'events on the left side occur just before those on...' could have different meanings, such as in a reading context where left to right reading direction would imply the right side. Nonetheless, based on the provided examples, particularly the spacetime diagram, the physics interpretation is likely intended.
The correct answer is options 1) Right side.