Can someone please explain to me why or how this statement is true? I don't understand it..
Two events that are simultaneous in one inertial frame of reference will not necessarily be simultaneous in any other inertial frame of reference.
Thank you
This is one of the fundamental postulates of the special theory of relativity. It has been proven experimentally to be true.
The separation of two events in space time can be written
dx^2 + dy^2 + dz^2 - c^2 dt^2
That quantity is invariant when transforming from one intertial coordinate system to another. It is possible for the spatial separation of the two events in four-dimensional spacetime to increase while the time interval decreases or become zero.
Certainly! I can help explain why this statement is true.
First, let's define what the components of the statement mean. An "inertial frame of reference" is a coordinate system that is not accelerating (i.e., either stationary or moving at a constant velocity). Simultaneous events refer to events that occur at the same time.
The statement is saying that if two events are simultaneous in one inertial frame of reference, they may not be simultaneous in another inertial frame of reference. This is due to a fundamental concept in physics known as the relativity of simultaneity, which arises from the theory of special relativity developed by Albert Einstein.
According to special relativity, time is not the same for all observers in relative motion. When two observers are moving relative to each other, they will measure time differently. This is because the speed of light is always the same for all observers, regardless of their relative motion.
In special relativity, the concept of simultaneity becomes relative. This means that whether two events are considered simultaneous or not depends on the observer's frame of reference. In other words, different observers moving at different velocities will perceive the timing of events differently.
For example, imagine two events happening at the same time in one frame of reference, where both events occur equidistant from an observer. However, if another observer is moving relative to the first observer, they will see the events occurring at different times because of the relative motion between the observers.
In summary, the statement implies that the concept of simultaneity is not absolute, but rather dependent on the observer's frame of reference due to the principles of special relativity. Different observers moving at different velocities will not necessarily agree on the simultaneity of events.