In the twin paradox, when Malik reaches the star, he perceives this as event P. Maha, observed from Earth, considers Malik's arrival at the star as event Q. They disagree on whether events Q and R are simultaneous, reflecting how simultaneity is relative in special relativity.

The asymmetry arises because one twin (Malik) changes inertial reference frames by turning around to return home, while the other twin (Maha) remains in a single inertial frame.

While Malik sees Maha in motion, and might expect time dilation effects, there is a lack of symmetry: Maha remains in her inertial frame, experiencing no acceleration, whereas Malik undergoes acceleration during his journey, altering his frame of reference and time experience.

Time dilation and length contraction.

Space-like intervals occur when the separation between events is such that (ct)² - x² is negative, implying these events can be simultaneous but not at the same location, as Δx cannot be zero but Δt can.

In spacetime diagrams, hyperbolas above the x-axis represent future events (occurring after ct=0), while those below indicate past events (before ct=0).

A 'time-like' interval occurs when the separation between two events is such that Δs², as given by (ct)² - x², is positive. This implies Δt is non-zero, and events can be causally connected.

(ct)² - x² = ±(constant)²

Time-like intervals on a spacetime diagram are separations between events involving a greater time difference than space difference, falling inside the light cone.

Lack of simultaneity occurs because the speed of light is constant in all inertial frames, affecting the timing of events as seen by moving observers.