Term

Definition
There is only one kind of time; we could measure all events with 1 moving clock that happened to be present at each event. 


Term

Definition
the time measured between two events either by a pair of synchronized clocks at rest in a given inertial reference frame (one clock present at each event) or by a single clock at rest in that inertial frame (if both events happen to occur at that clock in that frame). it is delta t. it is frame dependent i.e. the value varies according to which frame you choose to measure it in. 


Term
coordinate time differences are relative 

Definition
i.e. they deoend on one's choice of inertial frameeach observer will conclude that the clocks in the other frame are not synchronized. They will also disagree about the spatial separation between the events. 


Term

Definition
send out a pulse of lightmeasure the time it takes to come back. works because speed of light is the same in all reference frames 


Term
Geometric analogy for coordinate time 

Definition
Just as people using Cartesian coordinate systems oriented in different directions would get different (x,y) values for specific points on their respective grids, so do observers with different inertial frame get different coordinate time values for specific events. 


Term

Definition
On Cartesian coordinate grid, the distance between two points(like when you draw a straight line between them) is indisputableit is coordinateindependent. So is pathlength, or the distance of the path that you take from the one point to the other. 


Term
3 kinds of spatial separation 

Definition
coordinate separations, pathlength, and distance. 


Term

Definition
the time between two events measured by any clock present at both events. it is frameindependent. it is analogous to the spatial concept of pathlength. 


Term
Hafele and Keating experiment 

Definition
two synchronized atomic clocks; one is flown around the world, the other stays put. (both measured the proper time of the departure and return of the one clock). They differed by several nanoseconds; that proper time depends on the clock's worldline is an established experimental fact 


Term

Definition
The proper time measured by an inertial clock present at both events. It is frameindependent and depends on the separation of the events in space and time and nothing else. It is analogous to the spatial concept of distance. 


Term
particularities of the spacetime interval 

Definition
The spacetime interval is a very specific proper time and it is also a coordinate time 

