Length Contraction and Time Dilation | Special Relativity Ch. 5

This video is chapter 5 in my series on special relativity, and it covers how things that are moving (that is, moving relative to an inertial reference frame) at different speeds appear to be shorter in length... and longer in length. And shorter in time, and longer in time. It all makes sense, I promise, and is clear when you use the Lorentz transformation of coordinates of the events in question, enacted with a mechanical minkowski diagram, aka mechanical Lorentz transformation, aka spacetime globe.

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Created by Henry Reich

[TheLukass]

these things should be a standard equipment of any high school teaching physics!

[theCodyReeder]

Ok, question: how did you get the title to do that?

[danielfoulger]

I just want to say thank you to YouTubers like yourself 3B1B, mathlogger etc...I'm thinking of doing a physics degree and your beautiful explanations of complex concepts as well as beautiful visitations of maths principles is something to be admired. The amount of work that goes into these videos I can't even comprehend. I just think you should know that it's appreciated and that it is making a difference in my education (I am of course the only person whom I can speak for). Keep up the bloody amazing work because they're need to be more people like you in the world. The gift of explanation is something to envy Indeed.

[Zw]

Me: Just sitting here pretending I understand everything being said.

[tomerwolberg]

from my slow internet perspective: FIRST!!!

[rovertn]

Length contraction?
Nobody:

“When guys get into cold water”

[vidhuarora]

Physics




Where cats are 600 million metres long

[thechaosgardener]

I teach highschool physics and I approve this message. (Showing this to my students today) Thanks!

[deoxys]

The use of that contraption is absolutely brilliant. I found it much easier to digest the ideas in that manner. Great work!

[benvhan]

OK, I teach this...have taught this...to thousands of people. Much of what you have said has been great as enrichment, and I love it. Your completion of this pattern with "duration contraction" is...unbelievably brilliant, and–I believe–a pedagogical imperative. Thanks sir.

[imveryangryitsnotbutter]

1:40 - Or, to put it another way, imagine a person in New York City calls a person in Los Angeles.
New York Guy: "From my perspective, you are standing below me."
Los Angeles Guy: "Well from *my* perspective, *you* are standing below *me."*

[Raging.Geekazoid]

Fun fact: H.A. Lorentz thought time dilation and length contraction were real effects, i.e. that clocks literally run slower and objects literally get squished when they move. Einstein asked "relative to what?" and thought there couldn't be any answer to that question, i.e. "everything's relative". But that's never been proved. We might all be getting squished and living in slow motion without knowing it. 😶

[captainluke]

I really think that you and Mark Rober should start to sell your Larets (sorry if my spelling is off) transformation globe. I would be buy one immediately. Also, I think that for being YouTube channels, you both have made massive contributions to both physics, and science education with this globe.

[Lttmtf]

"the cat is six hundred million meters long"

[Mahesh_Shenoy]

When Henry announced his time globe I was super excited that I would get an intuitive approach to relativity.
I don't know if it's just me, but I didn't get much. It still felt pretty abstract.
Worst thing is I already know these basic stuff :-/
I think it would be easier if there was a slow real time video of Henry just playing with the time globe explaining what's going on. You know like a practical demo class.
That might help me and others like me to understand these videos much better.
Never the less, these videos are one of a kind and extremely informative, but very cognitively loading.

[AlejandroBravo]

4:00 shouldn't the colours of the lengths be the oposite?
To the left side of the equal the blue (or the length of the moving cat) and at the right side the orange (or length of the stationary one).

[Lttmtf]

"let's imagine I've placed a lightbulb at every point in space"

[BrokebackBob]

My brain has a 1gbs input rate without buffering and I just received confirmation that this video is too much info too fast and thus there is no information capture or retention. Fail.

[Fitzis]

I usually watch all of your videos. HOW DID I MISS AN ENTIRE SERIES?!?! I just found out.
Great job! As I'm struggling just now to make one of my students understand relativity, you deconstructing the subject so well is going to help me help her.

Thank you!

[PydraxAlpta]

Where can I get one if those spacetime globes? And great video, but kinda confusing still. Needed re-watch for getting it cleared.