Length contraction occurs infront of AND behind you?

In summary, length contraction happens on both sides of an object moving with respect to the observer, but the visual appearance of an object is affected only by how far away it is from the observer.
  • #1
coktail
118
1
If I am moving through space, things in front of me contract in the direction parallel to my movement. Does this also occur to objects behind me? For example, I look behind me, would things be contracted?

As always, thanks.
 
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  • #2
coktail said:
If I am moving through space, things in front of me contract in the direction parallel to my movement. Does this also occur to objects behind me? For example, I look behind me, would things be contracted?
Length contraction has nothing to do with where you look or where an object is with respect to you. Any object moving with respect to you will be measured by your frame to be contracted along its direction of motion.

This is different from the visual appearance of moving objects, if that's what you are interested in.
 
  • #3
coktail said:
If I am moving through space, things in front of me contract in the direction parallel to my movement. Does this also occur to objects behind me? For example, if I look behind me, would things be contracted?

Yes, the length contraction happens on both sides. However, that's not necessarily what you will SEE with your eyes if you turn around and look backwards because your eyes are responding to the light that hits them where you are, and that light left the object you're looking some time ago.

The thing to remember here is that length contraction and time dilation are what's left over after you've corrected for light travel time.
 
  • #4
Thank you. I'm not too interested in the visual appearance (at least in this thread), but more about whether if I am moving towards vs away from an object makes a difference in length contraction. From your post, I gather that wether I am moving towards or away from an object is irrelevant, and what matters is the relative velocity between myself and the object?

Edit: I posted this before I saw Nugatory's reply. Thank you to both of you!
 
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  • #5


Yes, according to the theory of special relativity, length contraction occurs in both directions - in front of and behind an object - when it is in motion. This means that if you were to look behind you while moving, objects in that direction would also appear contracted in the direction of your movement. This phenomenon is a result of the relative nature of space and time, where the perception of length and time intervals depends on the observer's frame of reference. So, while an object may appear contracted to one observer, it may appear at its normal length to another observer in a different frame of reference. This concept has been extensively studied and tested in various experiments and is a fundamental aspect of our understanding of the universe.
 

1. What is length contraction?

Length contraction is a phenomenon predicted by Einstein's theory of special relativity. It refers to the apparent shortening of objects in the direction of motion when observed from a different frame of reference. This effect becomes more significant as an object approaches the speed of light.

2. How does length contraction occur in front of and behind you?

Length contraction occurs in front of and behind an object because of the relative motion between the observer and the object. As the object moves closer to the speed of light, its length appears to shorten in the direction of motion, both in front of and behind the observer.

3. What is the formula for calculating length contraction?

The formula for calculating length contraction is L = L0 * √(1 - (v2/c2)), where L is the contracted length, L0 is the rest length of the object, v is the relative velocity between the observer and the object, and c is the speed of light.

4. Is length contraction a real physical phenomenon?

Yes, length contraction is a real physical phenomenon that has been observed and confirmed through various experiments and observations. It is an essential aspect of Einstein's theory of special relativity and has been validated by numerous experiments, such as the famous muon experiment.

5. Does length contraction only occur at high speeds?

Yes, length contraction only becomes significant at high speeds, specifically when an object approaches the speed of light. At everyday speeds, the effect of length contraction is negligible and cannot be observed. However, it is still a fundamental concept in understanding the behavior of objects in motion.

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