Undergrad Time Dilation Explained: Feynman Lectures 15-4

Click For Summary
SUMMARY

The discussion centers on the concept of time dilation as explained in Feynman Lectures 15-4. Participants clarify that a moving clock appears to run slow to an outside observer, who measures more elapsed time due to the relativistic effects described by the equation ##1/\sqrt{1-u^2/c^2}##. Confusion arises from the wording in various materials on Special Relativity, prompting suggestions for alternative resources. Recommended texts include "Special Relativity" by AP French and "Spacetime Physics" by Taylor & Wheeler, with the latter being favored for its clarity and modern approach.

PREREQUISITES
  • Understanding of Special Relativity concepts
  • Familiarity with time dilation and Lorentz transformations
  • Basic knowledge of relativistic equations, particularly ##u## and ##c##
  • Experience with physics textbooks and lecture materials
NEXT STEPS
  • Read "Special Relativity" by AP French for historical context and experimental evidence
  • Study "Spacetime Physics" by Taylor & Wheeler for a modern introduction to relativity
  • Explore the mathematical derivation of time dilation and Lorentz transformations
  • Investigate the concept of Terrell rotation in the context of Special Relativity
USEFUL FOR

Students of physics, educators teaching Special Relativity, and anyone seeking to clarify their understanding of time dilation and its implications in modern physics.

Jazzyrohan
Messages
32
Reaction score
0
Feynman Lectures 15-4 Transformation of time first para
http://www.feynmanlectures.caltech.edu/I_15.html
How is it possible that the moving clock slows down and also shows more time elapsed to the man outside?
 
Last edited:
Physics news on Phys.org
@Jazzyrohan I don't know where all the HTML cruft in the first paragraph your post is coming form, but it makes it unreadable.

However, the last sentence is readable and can be answered without even having to read the rest of your post:

Jazzyrohan said:
How is it possible that the moving clock slows down and also shows more time elapsed to the man outside?

It shows less time elapsed to the man outside. That is what "running slow" means.
 
  • Like
Likes russ_watters
All I see is a pair of broken image tags. You are aware that the Feynman lectures are available online? What diagram/equation/section/whatever are you talking about?
 
Ibix said:
All I see is a pair of broken image tags. You are aware that the Feynman lectures are available online? What diagram/equation/section/whatever are you talking about?
Please do take a look now.
 
PeterDonis said:
@Jazzyrohan I don't know where all the HTML cruft in the first paragraph your post is coming form, but it makes it unreadable.

However, the last sentence is readable and can be answered without even having to read the rest of your post:
It shows less time elapsed to the man outside. That is what "running slow" means.
Please do take a look now.
 
Jazzyrohan said:
Please do take a look now.
That agrees with what Peter said. The "outside" observer's watch measures more ticks (by a factor of ##1/\sqrt{1-u^2tc^2}##) because the "moving" observer's watch ticks slow.
 
Jazzyrohan said:
Please do take a look now.

The wording is confusing. The last sentence should read: "That is, when the clock in the spaceship records 1 second elapsed, as seen by the man in the ship, the clock carried by the man outside shows ##1 / \sqrt{1 - u^2 / c^2}## second to the man outside."
 
PeterDonis said:
The wording is confusing. The last sentence should read: "That is, when the clock in the spaceship records 1 second elapsed, as seen by the man in the ship, the clock carried by the man outside shows ##1 / \sqrt{1 - u^2 / c^2}## second to the man outside."
Why is it that every material I am reading on Special Relativity is consisting of confusing wordings? I am stuck on understanding time dilation due to this.I am thinking of reading Special Relativity by AP French now.Will that be a good choice?
 
Jazzyrohan said:
Why is it that every material I am reading on Special Relativity is consisting of confusing wordings?

What material have you read? The Feynman Lectures are generally good, but that's not to say they're perfect, and they are not specialized for teaching SR.

Jazzyrohan said:
I am thinking of reading Special Relativity by AP French now.Will that be a good choice?

Unfortunately I have not read that book so I can't comment on it. My usual suggestion is Taylor & Wheeler's Spacetime Physics.
 
  • #10
French's book is very good but old-fashioned. He discusses experimental evidence at length and covers a lot of ground (including Terrell rotation if I remember correctly). Old-fashioned because he uses relativistic mass and he doesn't spend much time on the geometric view of spacetime (four-vectors are covered but only briefly toward the end I think).

I second Taylor & Wheeler as an introduction.
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
903
  • · Replies 15 ·
Replies
15
Views
2K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 24 ·
Replies
24
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 13 ·
Replies
13
Views
1K
  • · Replies 18 ·
Replies
18
Views
2K