Proper Time and Time Dilatation

AI Thread Summary
Proper time is defined as the time measured by a clock moving along with an observer, and it is indeed the time elapsed on that clock. The confusion arises because, in the context of special relativity, proper time is always less than the coordinate time measured in a stationary frame due to time dilation. The relationship dτ = dt/γ highlights that proper time (dτ) is affected by the Lorentz factor (γ), which accounts for the relative velocity between observers. In the observer's rest frame, where they are not moving, γ equals 1, making proper time equal to coordinate time. Understanding these concepts is crucial for grasping the implications of time dilation in different reference frames.
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Homework Statement
I am a little confused with the concept of proper time
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I am a little confused with the concept of proper time: Using the invariance of the distance square in the Minkowski space, we can get the expression ##d \tau = \frac{d t}{ \gamma}## Now the problem:

Aren't the proper time the time measured by a moving clock? That is, if i am moving with speed v and carries with me a clock, "my" proper time is the time elapsed in my clock, right?

But, to the best of my knowledge, the time elapsed in a moving frame shouldn't be dilated? The so called time dilatation, so why the proper time in the expression above is lesser than the coordinate time?

The expression above has a special frame?
 
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In your rest frame, you are not moving, and thus ##\gamma = 1## and ##d\tau = dt##. There is no such thing as an inherently "moving frame", frames can only move relative to each other and you have to be careful in how you reference this.

In the frame where you move with speed ##v##, you indeed have ##d\tau = dt/\gamma## with ##dt## being the coordinate time differential in that frame.
 
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