1366 - "Train"

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gpq
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1366 - "Train"

Postby gpq » Fri May 09, 2014 6:56 am UTC

Image

Title text: 'Trains rotate the Earth around various axes while elevators shift its position in space.'

This only works if you lack an absolute reference frame. Which would also mean that you can't precisely calculate a sequence of events for everyone...
Last edited by gpq on Fri May 09, 2014 9:19 am UTC, edited 1 time in total.

eidako
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Re: 1366 - "Train"

Postby eidako » Fri May 09, 2014 6:57 am UTC

What moves the atmosphere?

xxnnss
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Re: 1366 - "Train"

Postby xxnnss » Fri May 09, 2014 7:10 am UTC

I think this refers to the new tldr wikipedia tumblr that was in the news.

Also an object that rotates along various axes is a tumbler.

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Re: 1366 - "Train"

Postby PayasYouDraw » Fri May 09, 2014 7:42 am UTC

The Little Prince had his own industrial revolution.
Ah-ooooh! Rolling back the rivers in Time!

0ed6893d
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Re: 1366 - "Train"

Postby 0ed6893d » Fri May 09, 2014 7:49 am UTC

I have to admit, I used to see it this way when I was a kid and my dad drove us around in the car.

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Re: 1366 - "Train"

Postby m.alessandrini » Fri May 09, 2014 7:57 am UTC

Relativity would probably have nothing to argue.

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Re: 1366 - "Train"

Postby Iv » Fri May 09, 2014 8:10 am UTC

Someone has been tinkering with worldview matrices without his medications again...

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Re: 1366 - "Train"

Postby krogoth » Fri May 09, 2014 8:23 am UTC

Not just the earth, but the entire universe!
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Re: 1366 - "Train"

Postby speising » Fri May 09, 2014 8:45 am UTC

what happens when two trains go in opposite directions?
also, why does the op link to 1365?

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Re: 1366 - "Train"

Postby peregrine_crow » Fri May 09, 2014 8:59 am UTC

speising wrote:what happens when two trains go in opposite directions?
also, why does the op link to 1365?


The train only rotates the earth when you are on board, otherwise it simply moves along the track.
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Re: 1366 - "Train"

Postby Native » Fri May 09, 2014 9:03 am UTC

Adhering to the old amaxostoichiocentric model are we?
I see the attraction, it's very intuitive, but it's not entirely uncontroversial you know...

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Re: 1366 - "Train"

Postby eviloatmeal » Fri May 09, 2014 9:16 am UTC

eidako wrote:What moves the atmosphere?

You do. How far, however, might be a topic for a What-If. "How far does air move when I breathe? How far is that per hour / day / year / lifetime?", or something along the lines of "what if everyone simultaneously breathed out in the same direction? Would that cause the Earth to stop spinning?"
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Gaita
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Re: 1366 - "Train"

Postby Gaita » Fri May 09, 2014 9:16 am UTC

More precisely, as our position relative to the sun and the stars doesn't change, we could say that trains rotate the universe using earth as the axis.

gpq
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Re: 1366 - "Train"

Postby gpq » Fri May 09, 2014 9:20 am UTC

speising wrote:what happens when two trains go in opposite directions?
also, why does the op link to 1365?


Oops!

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Re: 1366 - "Train"

Postby saengerbeatle » Fri May 09, 2014 9:33 am UTC

speising wrote:what happens when two trains go in opposite directions?

I always hate it when some idiot keeps pushing the earth into a direction where I don't want it to be. And don't get me started on those guys who keep giving me head wind when I'm riding my bike!

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Re: 1366 - "Train"

Postby orthogon » Fri May 09, 2014 9:37 am UTC

saengerbeatle wrote:And don't get me started on those guys who keep giving me head wind when I'm riding my bike!

I'm glad the word "wind" wasn't omitted.
xtifr wrote:... and orthogon merely sounds undecided.

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da Doctah
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Re: 1366 - "Train"

Postby da Doctah » Fri May 09, 2014 9:57 am UTC

eidako wrote:What moves the atmosphere?
Some damn troublemaking butterfly in Argentina!

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Re: 1366 - "Train"

Postby AlecsandraSmart » Fri May 09, 2014 10:25 am UTC

This train joke works because it is obvious, even to semi-nerds, that there is no 'proper-place' - the one place that all measurements should be taken from because it is fixed. 'Measure from the earth because the earth is fixed' but the earth is only fixed when it is compared to itself.

But it is less obvious, even to uber-nerds, that there is no 'proper-time' - the one physical phenomena that all measurements should be taken against because it is fixed. 'Calibrate your clock with light because the speed of light is constant', but the speed of light is only constant when it is measured in terms of itself.

We of the 'Campaign for Real Time' (CRT) think it is unfair that the principle of relativity should apply only to place, but not to pace, or space. If a ray of light is faster in orbit than on the surface, so called 'physicists' will say "Look, time itself slows down as gravity increases". But we at the CRT say no! It is not 'time itself', it is the thing you are measuring time with. 'Time' is not a physical thing, so General Relativity is not even a proper physical theory. If increasing gravity makes light slow to a stop, that is a physical phenomenon. But if increasing gravity makes 'time' dilate to infinity, that is proof that your theory is wrong.

Join the Campaign for Real Time.

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Re: 1366 - "Train"

Postby nomeata » Fri May 09, 2014 10:35 am UTC

The comic left me wondering this:

If I get a train up to speed, I have to invest a lot of energy; some function of mass and speed difference. But if I instead of accelerating the train accelerate the earth beneath it (and the athmosphere (and the universe)), the amount of energy required would be enormous. Yet there in the comic we see it happening, so it must be possible. Where is the mistake?

Similarly: Stuff on rotating objects are usually subject to a centrifugal force. So when someone rides a very fast train in the way shown by the comit, wouldn’t that mean that we all (who are not on the train) are going to weigh less?

Please enlighten me!

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Re: 1366 - "Train"

Postby brenok » Fri May 09, 2014 11:00 am UTC

nomeata wrote:The comic left me wondering this:

If I get a train up to speed, I have to invest a lot of energy; some function of mass and speed difference. But if I instead of accelerating the train accelerate the earth beneath it (and the athmosphere (and the universe)), the amount of energy required would be enormous. Yet there in the comic we see it happening, so it must be possible. Where is the mistake?

I believe the difference in energy would have to be measured from an inertial reference frame, an accelerating train isn't one.

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3rdtry
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Re: 1366 - "Train"

Postby 3rdtry » Fri May 09, 2014 11:23 am UTC

Ah, but then why do the people on the train feel acceleration whereas people on the rest of the planet don't?

I do believe I'm onto something here. What is the email of the president of physics?

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Re: 1366 - "Train"

Postby cellocgw » Fri May 09, 2014 11:31 am UTC

"Let it rain,
who cares?
I've got a train upstairs..."

Still one of my alltime favorite poems.
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Re: 1366 - "Train"

Postby Brickmack » Fri May 09, 2014 11:32 am UTC

Well, this is true. But since trains have such a low mass, its very inefficient and they end up moving themselves more than Earth

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Re: 1366 - "Train"

Postby jerrys » Fri May 09, 2014 11:33 am UTC

I think he missed the boat on this one -- if he had said "Universe" instead of "Earth", he (sort of) wouldn't even be wrong! (Mach's principle)

grubernd
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Re: 1366 - "Train"

Postby grubernd » Fri May 09, 2014 11:40 am UTC

it gets even better when you get off your seat on the train.
you can push a train out of a station just by walking.
or bring it to a halt. try it, it's fun.

ah, that thing called perception.

the world is subjective.
at least mine is, cant speak for yours.

:D

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Biliboy
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Re: 1366 - "Train"

Postby Biliboy » Fri May 09, 2014 12:13 pm UTC

Reminds me of a short story I read in a sf anthology years ago, about an oak tree on the side of the road, growing from a sapling to a full grown tree, learning to move faster and faster past the people moving by as they walked, then rode horses, then moved to cars. It claimed the most difficult part was rushing past two cars moving in opposite directions at the same time. The saddest part was when it had to ram full speed into a car occupied by a drunk.

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Re: 1366 - "Train"

Postby rmsgrey » Fri May 09, 2014 12:14 pm UTC

For daily life, the model that I stay put and the rest of the universe moves around me is pretty useful - so is the model that the Earth is stationary and the Sun orbits it.

For doing calculations, the maths is much, much simpler when you pick a reference frame that's close enough to inertial for the objects you're considering, and where most of the mass is more-or-less still on average.

In principle, it's possible to do all of Physics with a reference frame anchored a couple of inches behind the bridge of my nose, but even on human scales, that's sufficiently non-inertial that the maths would be intractable. Saying that the Earth orbits the Sun on an elliptical path is just a trick to make the maths easier (everyone knows the Sun really orbits the Earth in a circle-plus-epicycles)

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Re: 1366 - "Train"

Postby gmalivuk » Fri May 09, 2014 12:33 pm UTC

AlecsandraSmart wrote:This train joke works because it is obvious, even to semi-nerds, that there is no 'proper-place' - the one place that all measurements should be taken from because it is fixed. 'Measure from the earth because the earth is fixed' but the earth is only fixed when it is compared to itself.

But it is less obvious, even to uber-nerds, that there is no 'proper-time' - the one physical phenomena that all measurements should be taken against because it is fixed. 'Calibrate your clock with light because the speed of light is constant', but the speed of light is only constant when it is measured in terms of itself.

We of the 'Campaign for Real Time' (CRT) think it is unfair that the principle of relativity should apply only to place, but not to pace, or space. If a ray of light is faster in orbit than on the surface, so called 'physicists' will say "Look, time itself slows down as gravity increases". But we at the CRT say no! It is not 'time itself', it is the thing you are measuring time with. 'Time' is not a physical thing, so General Relativity is not even a proper physical theory. If increasing gravity makes light slow to a stop, that is a physical phenomenon. But if increasing gravity makes 'time' dilate to infinity, that is proof that your theory is wrong.

Join the Campaign for Real Time.

It's almost as if you still have no idea what physicists mean when they say "time"...
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Re: 1366 - "Train"

Postby Jhnbytwoo » Fri May 09, 2014 12:35 pm UTC

AlecsandraSmart wrote:This train joke works because it is obvious, even to semi-nerds, that there is no 'proper-place' - the one place that all measurements should be taken from because it is fixed. 'Measure from the earth because the earth is fixed' but the earth is only fixed when it is compared to itself.

But it is less obvious, even to uber-nerds, that there is no 'proper-time' - the one physical phenomena that all measurements should be taken against because it is fixed. 'Calibrate your clock with light because the speed of light is constant', but the speed of light is only constant when it is measured in terms of itself.

We of the 'Campaign for Real Time' (CRT) think it is unfair that the principle of relativity should apply only to place, but not to pace, or space. If a ray of light is faster in orbit than on the surface, so called 'physicists' will say "Look, time itself slows down as gravity increases". But we at the CRT say no! It is not 'time itself', it is the thing you are measuring time with. 'Time' is not a physical thing, so General Relativity is not even a proper physical theory. If increasing gravity makes light slow to a stop, that is a physical phenomenon. But if increasing gravity makes 'time' dilate to infinity, that is proof that your theory is wrong.

Join the Campaign for Real Time.

Before looking it up and learning that you were referencing a Hitchhiker's Guide thing, I was worried that Gene Ray found the xkcd fora.

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Re: 1366 - "Train"

Postby gmalivuk » Fri May 09, 2014 12:38 pm UTC

Oh, is it a reference?

The same poster insisted on a rather backwards understanding of "time" in another comic thread as well, so I just assumed it was that notion again.

Sorry if that assumption was in error.
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RogueCynic
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Re: 1366 - "Train"

Postby RogueCynic » Fri May 09, 2014 12:39 pm UTC

Isn't this how the Planet Express ship moves?
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Re: 1366 - "Train"

Postby rmsgrey » Fri May 09, 2014 12:57 pm UTC

gmalivuk wrote:Oh, is it a reference?

The same poster insisted on a rather backwards understanding of "time" in another comic thread as well, so I just assumed it was that notion again.

Sorry if that assumption was in error.


The Campaign for Real Time is mentioned in Life, The Universe, And Everything - conservationists worried about pollution of time from all the time travel going on, and the reason Slartibartfast knows where/when to find the pieces of the Wikkit Gate.

On the other hand, the H2G2 version had no known problems with Special/General Relativity, so that's either a new wrinkle, or evidence that this is some other organisation with a similar name (the H2G2 version is shortened to CamTim rather than CRT, which supports the latter interpretation)

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Re: 1366 - "Train"

Postby orthogon » Fri May 09, 2014 1:31 pm UTC

It's also worth mentioning for those outside the UK that "Campaign for Real Time" evokes the Campaign for Real Ale (Camra), an organisation formed to encourage pubs to serve cask-conditioned hand-pulled beers rather than the sterilised, CO2-powered lagers and keg beers that were becoming increasingly common in the 1970s. The campaign has been very successful, with most proper pubs serving Real Ales (bars and restaurants are a different story). I'm not sure whether the Restaurant at the end of the Universe served any such ales for those not so partial to the Pan-Galactic Gargle Blaster.
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1366 - "Train"

Postby gmalivuk » Fri May 09, 2014 1:42 pm UTC

Was beer everywhere in the English-speaking world particularly shitty in the 1970s? That was a bit of a dark age here in the US as well, before smaller breweries started becoming a thing the following decade.
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Re: 1366 - "Train"

Postby cct » Fri May 09, 2014 2:04 pm UTC

0ed6893d wrote:I have to admit, I used to see it this way when I was a kid and my dad drove us around in the car.


Strangely, my 4-year-old objected very emotionally when I tried to explain that our feet were pushing the sidewalk away until our house reached "here." (The original question was, "When will we be 'there?'")

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Re: 1366 - "Train"

Postby mathmannix » Fri May 09, 2014 2:07 pm UTC

Well sure, if you believe the world revolves around you.
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Re: 1366 - "Train"

Postby itallmakessense » Fri May 09, 2014 2:25 pm UTC

Same as how the spaceship in Futurama works. No, I don't believe you don't watch Futurama.

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Re: 1366 - "Train"

Postby ctdonath » Fri May 09, 2014 3:35 pm UTC

It's all just VR stimuli provided to my brain wired up & sitting in this vat of chemicals. Of course "moving the universe" and "what about the atmosphere" are trivial 3D translation/rotation problems, despite what all you NPCs "think".

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Re: 1366 - "Train"

Postby airdrik » Fri May 09, 2014 4:10 pm UTC

mathmannix wrote:Well sure, if you believe the world revolves around you.

It does! but only when I'm in one of those human gyroscopes.
The forces from the earth spinning around you like that can be really dizzying.

ctdonath wrote:It's all just VR stimuli provided to my brain wired up & sitting in this vat of chemicals. Of course "moving the universe" and "what about the atmosphere" are trivial 3D translation/rotation problems, despite what all you NPCs "think".

Isn't it amazing how much information is provided to my consciousness.
To think that my perception is able to produce all of this new information that my consciousness or subconscious hadn't even imagined before!
At times I almost believe that there is something outside of my self - outside of my perception - which is providing my perception with all of this information that is being presented to my consciousness.
What can it all mean?
Is there really something outside of me?
Perchance there may be others who are experiencing the universe in a similar manner?
Are there occasions when that which is outside of my perception and coincides with that which is outside someone else's perception?
What kinds of interactions are really possible when that happens?

No I don't really believe that anything outside my perception exists, but I do wonder sometimes.
The things that my perception presents to my consciousness are really strange.

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Re: 1366 - "Train"

Postby gmalivuk » Fri May 09, 2014 4:35 pm UTC

You only think they're strange or novel, though. If you were really unsure of the existence of anything outside your head, you wouldn't so confidently declare that you were definitely having novel experiences.
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