0265: "Choices: Part 2"

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rhalleys5th
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Postby rhalleys5th » Tue May 22, 2007 5:16 pm UTC

Had to laugh at the first panel -- I always start my physics homework after midnight.

weziman
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Postby weziman » Tue May 22, 2007 6:50 pm UTC

In case anyone's wondering about the math behind this:

(0.2c-(-0.2c))/(1-(0.2c)*(-0.2c)/c^2) = 0.4c/1.04c ~= 0.385c = 38.5% speed of light

time dilation is the lorentz factor:

sqrt(1-(0.385c)^2/c^2) = 0.923 = 92.3%

My question is: How are are the occupants of the passing spaceship able to observe time dilation? Or did they just derive the dilation from the observed relative velocity?

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Spaz Funbag
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Postby Spaz Funbag » Tue May 22, 2007 7:37 pm UTC

anotherangel wrote:Maybe he is controlling her reality. What he writes, in his homework, is what's going to happen to her. So she could actually be in his homework.


That leaves the question, is her desk part of the "homework-world" or the "real world"?
Assuming the "real world", then the rift would be a way into his homework.
Alternatively, science in general (oooh, imagine creeping into the SI people's books and change the "planck constant" to the "spaz funbag constant" sweet!).

Assuming the "homework world", she would not be real, but have always been a part of his homework. Maybe she is his dream or imaginary friend that he gets when homework is too boring, or she has ever since been stuck in that particular "question". Furthermore, is she only in his homework or also in other people's homework?

Finally, where does the door lead? Into reality? Into different homework? Into the "homework mainframe hub"?
Alternatively, is she a girl from reality, entering THE ROOM without knowing so, and by closing the door, disconnects herself from reality, like if that room is like an airlock between Reality and Science?

Only Time will tell...alternatively, Randall.



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Drake Zure
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Postby Drake Zure » Tue May 22, 2007 8:04 pm UTC

maybe they're gonna just switch places; he goes to her desk, she goes to his.
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bookishbunny
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Postby bookishbunny » Tue May 22, 2007 8:09 pm UTC

Drake Zure wrote:maybe they're gonna just switch places; he goes to her desk, she goes to his.


NO!!! They must fall in love, too! They just gotta!!!
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tendays
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Postby tendays » Tue May 22, 2007 8:33 pm UTC

weziman wrote:My question is: How are are the occupants of the passing spaceship able to observe time dilation? Or did they just derive the dilation from the observed relative velocity?


By looking at the girl in the bubble - they see her moving and breathing and talking slower than she would if they were going at the same speed in the same direction. (And she observes the same slowness about them). (This "slowness" is observed after correcting the doppler effect).

I have to say that this week we are witnessing the birth of an xkcd classic ! Can't wait to see what is going to happen next :-)

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Istrom
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Postby Istrom » Tue May 22, 2007 9:57 pm UTC

Let's remember the title. Choices. We have to find the choice that was taken in this comic. I think it's along the lines of the guy's making a hypothetical situation where he's in a spaceship at the same point as described in his homework, to get the answers easier. then he hypothesizes (daydreams?) about the possibility of having true love in space. then he has to decide whether or not to turn around and save the girl he loves.

or summat

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archgoon
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Postby archgoon » Tue May 22, 2007 10:27 pm UTC

I think the comic needs to have a little disclaimer "Distances not drawn to scale."

That, or the people are talking _very_ fast.
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Postby UmbralRaptor » Tue May 22, 2007 11:07 pm UTC

archgoon wrote:That, or the people are talking _very_ fast.

It's generally assumed that you are able to talk that fast in those sorts of special relativity problems. And you have sort of infinitely fast measuring system (or enough time so that you can get the photons from those ships approaching at >.999 c and figure out how fast they're going...)

Now if only I could think that fast in real life...
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Phob0s
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Postby Phob0s » Tue May 22, 2007 11:08 pm UTC

Istrom wrote:Let's remember the title. Choices. We have to find the choice that was taken in this comic. I think it's along the lines of the guy's making a hypothetical situation where he's in a spaceship at the same point as described in his homework, to get the answers easier. then he hypothesizes (daydreams?) about the possibility of having true love in space. then he has to decide whether or not to turn around and save the girl he loves.

or summat


yeah, I agree. Although it's possible he already knows her, and that's why he is daydreaming about her in the first place.

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Drake Zure
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Postby Drake Zure » Tue May 22, 2007 11:10 pm UTC

Phob0s wrote:
Istrom wrote:Let's remember the title. Choices. We have to find the choice that was taken in this comic. I think it's along the lines of the guy's making a hypothetical situation where he's in a spaceship at the same point as described in his homework, to get the answers easier. then he hypothesizes (daydreams?) about the possibility of having true love in space. then he has to decide whether or not to turn around and save the girl he loves.

or summat


yeah, I agree. Although it's possible he already knows her, and that's why he is daydreaming about her in the first place.


in that case, i think the daydream would probably be a little kinkier...
benjhuey wrote:
IceMod wrote:The fingers did surprise me though.

That's what SHE said.
And then she left. I wonder why...

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Elise
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Postby Elise » Wed May 23, 2007 1:24 am UTC

Just about every time i sit down to yet another homework set, i think somewhere there is a beautiful day i am missing, something interesting happening, something better than calculating the density of a neutron star in rhino masses per teaspoon. The love of my life could be floating just outside my door, but i am locked in the lab, Chocking my brain full of labby goodness. Then i realize i have student loans to pay off because of this mess and get back to work.

Maybe that is what the second comic is about. The girl in the first comic is definitely having an interesting time.

In fact, i think i had that exact thought when doing problems similar to this.

damn you Lorentz and your transformation!


its about 3 rhinos per teaspoon, rhinos may vary.
more delicious than ever!

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Vandole
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Postby Vandole » Wed May 23, 2007 2:47 am UTC

Ren wrote:I like that idea, bookishbunny! That, or he gets his own cosmic rip, and they're lost together! Awww.

*hopes no one noticed sentimentality*

I'm tough, really!

We're geeks. The majority of us like it when you're sentimental like that.
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JoshuaZ
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Re: "Choices: Part 2" Discussion

Postby JoshuaZ » Wed May 23, 2007 4:34 am UTC

The LuigiManiac wrote:
Title text: Maybe someday I'll get to write the Wikipedia article about this place. Wait, damn, original research.


I love the title text. Now, if only we can get all the other popular webcomics add little advertisements for Wikipedia's No Original Research policy...maybe then the fans won't feel a need to add speculation about every little detail.

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Kuuchu
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Re: "Choices: Part 2" Discussion

Postby Kuuchu » Wed Jan 20, 2010 3:19 pm UTC

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